[PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Anup Patel]

The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
are frozen and finished public review at the RISC-V International.

Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
and RPMI system MSI driver This series also includes ACPI support
for SBI MPXY mailbox controller and RPMI system MSI drivers.

These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
at: https://github.com/avpatel/linux.git

To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
machine with OpenSBI and QEMU from the dev-upstream branch at:
https://github.com/ventanamicro/opensbi.git
https://github.com/ventanamicro/qemu.git

[1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
[2] https://github.com/riscv-non-isa/riscv-rpmi/releases

Changes since v7:
 - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21

Changes since v6:
 - Rebased the series on Linux-6.16-rc4
 - Added Stephen's Reviewed-by in appropriate patches
 - Addressed Andy's comments on PATCH5, PATCH6, PATCH9, and PATCH14
 - New PATCH6 in this series which is factored-out from PATCH7

Changes since v5:
 - Rebased the series on Linux-6.16-rc2
 - Added Conor's Reviewed-by in all DT binding patches
 - Addressed Andy's comments on PATCH5
 - Addressed Tglx's comments on PATCH12 and PATCH21

Changes since v4:
 - Rebased the series on Linux-6.16-rc1
 - Dropped PATCH1 since a similar change is already merged
   https://lore.kernel.org/linux-riscv/20250523101932.1594077-4-cleger@rivosinc.com/
 - Addressed Andy's comments on PATCH4, PATCH5, PATCH6, PATCH7,
   PATCH13, and PATCH17
 - Addressed Atish's comments on PATCH11 and PATCH12
 - Addressed Conor's comments on PATCH9

Changes since v3:
 - Rebased the series on Linux-6.15-rc7
 - Updated PATCH2 DT bindings as-per Rob's suggestion
 - Improved request_threaded_irq() usage in PATCH7
 - Updated PATCH10 clk-rpmi driver as-per commments from Andy
 - Updated PATCH13 irq-riscv-rpmi-sysmsi driver as-per comments
   from Andy and Tglx
 - Addressed ACPI related comments in PATCH14, PATCH15, PATCH18,
   PATCH20 and PATCH21

Changes since v2:
 - Dropped the "RFC" tag from series since the SBI v3.0 and
   RPMI v1.0 specifications are now frozen
 - Rebased the series on Linux-6.15-rc5
 - Split PATCH8 of v2 into two patches adding separate DT
   bindings for "riscv,rpmi-mpxy-clock" and "riscv,rpmi-clock"
 - Split PATCH10 of v2 into two patches adding separate DT
   bindings for "riscv,rpmi-mpxy-system-msi" and
   "riscv,rpmi-system-msi"
 - Addressed comments from TGLX on PATCH11 of v2 adding irqchip
   driver for RPMI system MSI
 - Addressed ACPI related comments in PATCH15 and PATCH16 of v2
 - New PATCH17 and PATCH18 in this series

Changes since v1:
 - Addressed DT bindings related comments in PATCH2, PATCH3, and
   PATCH7 of v1 series
 - Addressed comments in PATCH6 and PATCH8 of v1 series
 - New PATCH6 in v2 series to allow fwnode based mailbox channel
   request
 - New PATCH10 and PATCH11 to add RPMI system MSI based interrupt
   controller driver
 - New PATCH12 to PATCH16 which adds ACPI support in SBI MPXY
   mailbox driver and RPMI system MSI driver
 - New PATCH17 to enable required kconfig option to allow graceful
   shutdown on QEMU virt machine

Anup Patel (14):
  dt-bindings: mailbox: Add bindings for RPMI shared memory transport
  dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension
  RISC-V: Add defines for the SBI message proxy extension
  mailbox: Add common header for RPMI messages sent via mailbox
  mailbox: Allow controller specific mapping using fwnode
  byteorder: Add memcpy_to_le32() and memcpy_from_le32()
  mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver
  dt-bindings: clock: Add RPMI clock service message proxy bindings
  dt-bindings: clock: Add RPMI clock service controller bindings
  dt-bindings: Add RPMI system MSI message proxy bindings
  dt-bindings: Add RPMI system MSI interrupt controller bindings
  irqchip: Add driver for the RPMI system MSI service group
  RISC-V: Enable GPIO keyboard and event device in RV64 defconfig
  MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers

Rahul Pathak (1):
  clk: Add clock driver for the RISC-V RPMI clock service group

Sunil V L (9):
  ACPI: property: Refactor acpi_fwnode_get_reference_args() to support
    nargs_prop
  ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()
  ACPI: scan: Update honor list for RPMI System MSI
  ACPI: RISC-V: Create interrupt controller list in sorted order
  ACPI: RISC-V: Add support to update gsi range
  ACPI: RISC-V: Add RPMI System MSI to GSI mapping
  irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()
  mailbox/riscv-sbi-mpxy: Add ACPI support
  irqchip/riscv-rpmi-sysmsi: Add ACPI support

 .../bindings/clock/riscv,rpmi-clock.yaml      |   64 ++
 .../bindings/clock/riscv,rpmi-mpxy-clock.yaml |   64 ++
 .../riscv,rpmi-mpxy-system-msi.yaml           |   67 ++
 .../riscv,rpmi-system-msi.yaml                |   74 ++
 .../mailbox/riscv,rpmi-shmem-mbox.yaml        |  124 ++
 .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml |   51 +
 MAINTAINERS                                   |   15 +
 arch/riscv/configs/defconfig                  |    2 +
 arch/riscv/include/asm/irq.h                  |    6 +
 arch/riscv/include/asm/sbi.h                  |   63 +
 drivers/acpi/property.c                       |  128 ++-
 drivers/acpi/riscv/irq.c                      |   75 +-
 drivers/acpi/scan.c                           |    2 +
 drivers/base/property.c                       |    2 +-
 drivers/clk/Kconfig                           |    8 +
 drivers/clk/Makefile                          |    1 +
 drivers/clk/clk-rpmi.c                        |  616 ++++++++++
 drivers/irqchip/Kconfig                       |    7 +
 drivers/irqchip/Makefile                      |    1 +
 drivers/irqchip/irq-riscv-imsic-early.c       |    2 +
 drivers/irqchip/irq-riscv-rpmi-sysmsi.c       |  328 ++++++
 drivers/mailbox/Kconfig                       |   11 +
 drivers/mailbox/Makefile                      |    2 +
 drivers/mailbox/mailbox.c                     |   65 +-
 drivers/mailbox/riscv-sbi-mpxy-mbox.c         | 1017 +++++++++++++++++
 include/linux/byteorder/generic.h             |   16 +
 include/linux/mailbox/riscv-rpmi-message.h    |  243 ++++
 include/linux/mailbox_controller.h            |    3 +
 include/linux/wordpart.h                      |   16 +
 29 files changed, 2990 insertions(+), 83 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
 create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
 create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
 create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
 create mode 100644 drivers/clk/clk-rpmi.c
 create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c
 create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c
 create mode 100644 include/linux/mailbox/riscv-rpmi-message.h

-- 
2.43.0

[PATCH v8 01/24] dt-bindings: mailbox: Add bindings for RPMI shared memory transport

[Anup Patel]

Add device tree bindings for the common RISC-V Platform Management
Interface (RPMI) shared memory transport as a mailbox controller.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../mailbox/riscv,rpmi-shmem-mbox.yaml        | 124 ++++++++++++++++++
 1 file changed, 124 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml b/Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
new file mode 100644
index 000000000000..3aabc52a0c03
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
@@ -0,0 +1,124 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/riscv,rpmi-shmem-mbox.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V Platform Management Interface (RPMI) shared memory mailbox
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a common shared
+  memory based RPMI transport. This RPMI shared memory transport integrates as
+  mailbox controller in the SBI implementation or supervisor software whereas
+  each RPMI service group is mailbox client in the SBI implementation and
+  supervisor software.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+properties:
+  compatible:
+    const: riscv,rpmi-shmem-mbox
+
+  reg:
+    minItems: 2
+    items:
+      - description: A2P request queue base address
+      - description: P2A acknowledgment queue base address
+      - description: P2A request queue base address
+      - description: A2P acknowledgment queue base address
+      - description: A2P doorbell address
+
+  reg-names:
+    minItems: 2
+    items:
+      - const: a2p-req
+      - const: p2a-ack
+      - enum: [ p2a-req, a2p-doorbell ]
+      - const: a2p-ack
+      - const: a2p-doorbell
+
+  interrupts:
+    maxItems: 1
+    description:
+      The RPMI shared memory transport supports P2A doorbell as a wired
+      interrupt and this property specifies the interrupt source.
+
+  msi-parent:
+    description:
+      The RPMI shared memory transport supports P2A doorbell as a system MSI
+      and this property specifies the target MSI controller.
+
+  riscv,slot-size:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 64
+    description:
+      Power-of-2 RPMI slot size of the RPMI shared memory transport.
+
+  riscv,a2p-doorbell-value:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 0x1
+    description:
+      Value written to the 32-bit A2P doorbell register.
+
+  riscv,p2a-doorbell-sysmsi-index:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      The RPMI shared memory transport supports P2A doorbell as a system MSI
+      and this property specifies system MSI index to be used for configuring
+      the P2A doorbell MSI.
+
+  "#mbox-cells":
+    const: 1
+    description:
+      The first cell specifies RPMI service group ID.
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - riscv,slot-size
+  - "#mbox-cells"
+
+anyOf:
+  - required:
+      - interrupts
+  - required:
+      - msi-parent
+
+additionalProperties: false
+
+examples:
+  - |
+    // Example 1 (RPMI shared memory with only 2 queues):
+    mailbox@10080000 {
+        compatible = "riscv,rpmi-shmem-mbox";
+        reg = <0x10080000 0x10000>,
+              <0x10090000 0x10000>;
+        reg-names = "a2p-req", "p2a-ack";
+        msi-parent = <&imsic_mlevel>;
+        riscv,slot-size = <64>;
+        #mbox-cells = <1>;
+    };
+  - |
+    // Example 2 (RPMI shared memory with only 4 queues):
+    mailbox@10001000 {
+        compatible = "riscv,rpmi-shmem-mbox";
+        reg = <0x10001000 0x800>,
+              <0x10001800 0x800>,
+              <0x10002000 0x800>,
+              <0x10002800 0x800>,
+              <0x10003000 0x4>;
+        reg-names = "a2p-req", "p2a-ack", "p2a-req", "a2p-ack", "a2p-doorbell";
+        msi-parent = <&imsic_mlevel>;
+        riscv,slot-size = <64>;
+        riscv,a2p-doorbell-value = <0x00008000>;
+        #mbox-cells = <1>;
+    };
-- 
2.43.0

[PATCH v8 02/24] dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension

[Anup Patel]

Add device tree bindings for the RISC-V SBI Message Proxy (MPXY)
extension as a mailbox controller.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml | 51 +++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml b/Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
new file mode 100644
index 000000000000..061437a0b45a
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/riscv,sbi-mpxy-mbox.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V SBI Message Proxy (MPXY) extension based mailbox
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V SBI Message Proxy (MPXY) extension [1] allows supervisor
+  software to send messages through the SBI implementation (M-mode
+  firmware or HS-mode hypervisor). The underlying message protocol
+  and message format used by the supervisor software could be some
+  other standard protocol compatible with the SBI MPXY extension
+  (such as RISC-V Platform Management Interface (RPMI) [2]).
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+  [2] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+properties:
+  compatible:
+    const: riscv,sbi-mpxy-mbox
+
+  "#mbox-cells":
+    const: 2
+    description:
+      The first cell specifies channel_id of the SBI MPXY channel,
+      the second cell specifies MSG_PROT_ID of the SBI MPXY channel
+
+required:
+  - compatible
+  - "#mbox-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    mailbox {
+          compatible = "riscv,sbi-mpxy-mbox";
+          #mbox-cells = <2>;
+    };
-- 
2.43.0

[PATCH v8 03/24] RISC-V: Add defines for the SBI message proxy extension

[Anup Patel]

Add defines for the new SBI message proxy extension which is part
of the SBI v3.0 specification.

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Co-developed-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/include/asm/sbi.h | 63 ++++++++++++++++++++++++++++++++++++
 include/linux/wordpart.h     |  8 +++++
 2 files changed, 71 insertions(+)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 341e74238aa0..22f6e70cd32e 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -10,6 +10,7 @@
 #include <linux/types.h>
 #include <linux/cpumask.h>
 #include <linux/jump_label.h>
+#include <linux/wordpart.h>
 
 #ifdef CONFIG_RISCV_SBI
 enum sbi_ext_id {
@@ -36,6 +37,7 @@ enum sbi_ext_id {
 	SBI_EXT_STA = 0x535441,
 	SBI_EXT_NACL = 0x4E41434C,
 	SBI_EXT_FWFT = 0x46574654,
+	SBI_EXT_MPXY = 0x4D505859,
 
 	/* Experimentals extensions must lie within this range */
 	SBI_EXT_EXPERIMENTAL_START = 0x08000000,
@@ -430,6 +432,67 @@ enum sbi_fwft_feature_t {
 
 #define SBI_FWFT_SET_FLAG_LOCK			BIT(0)
 
+enum sbi_ext_mpxy_fid {
+	SBI_EXT_MPXY_GET_SHMEM_SIZE,
+	SBI_EXT_MPXY_SET_SHMEM,
+	SBI_EXT_MPXY_GET_CHANNEL_IDS,
+	SBI_EXT_MPXY_READ_ATTRS,
+	SBI_EXT_MPXY_WRITE_ATTRS,
+	SBI_EXT_MPXY_SEND_MSG_WITH_RESP,
+	SBI_EXT_MPXY_SEND_MSG_WITHOUT_RESP,
+	SBI_EXT_MPXY_GET_NOTIFICATION_EVENTS,
+};
+
+enum sbi_mpxy_attribute_id {
+	/* Standard channel attributes managed by MPXY framework */
+	SBI_MPXY_ATTR_MSG_PROT_ID		= 0x00000000,
+	SBI_MPXY_ATTR_MSG_PROT_VER		= 0x00000001,
+	SBI_MPXY_ATTR_MSG_MAX_LEN		= 0x00000002,
+	SBI_MPXY_ATTR_MSG_SEND_TIMEOUT		= 0x00000003,
+	SBI_MPXY_ATTR_MSG_COMPLETION_TIMEOUT	= 0x00000004,
+	SBI_MPXY_ATTR_CHANNEL_CAPABILITY	= 0x00000005,
+	SBI_MPXY_ATTR_SSE_EVENT_ID		= 0x00000006,
+	SBI_MPXY_ATTR_MSI_CONTROL		= 0x00000007,
+	SBI_MPXY_ATTR_MSI_ADDR_LO		= 0x00000008,
+	SBI_MPXY_ATTR_MSI_ADDR_HI		= 0x00000009,
+	SBI_MPXY_ATTR_MSI_DATA			= 0x0000000A,
+	SBI_MPXY_ATTR_EVENTS_STATE_CONTROL	= 0x0000000B,
+	SBI_MPXY_ATTR_STD_ATTR_MAX_IDX,
+	/*
+	 * Message protocol specific attributes, managed by
+	 * the message protocol specification.
+	 */
+	SBI_MPXY_ATTR_MSGPROTO_ATTR_START	= 0x80000000,
+	SBI_MPXY_ATTR_MSGPROTO_ATTR_END		= 0xffffffff
+};
+
+/* Possible values of MSG_PROT_ID attribute as-per SBI v3.0 (or higher) */
+enum sbi_mpxy_msgproto_id {
+	SBI_MPXY_MSGPROTO_RPMI_ID = 0x0,
+};
+
+/* RPMI message protocol specific MPXY attributes */
+enum sbi_mpxy_rpmi_attribute_id {
+	SBI_MPXY_RPMI_ATTR_SERVICEGROUP_ID = SBI_MPXY_ATTR_MSGPROTO_ATTR_START,
+	SBI_MPXY_RPMI_ATTR_SERVICEGROUP_VERSION,
+	SBI_MPXY_RPMI_ATTR_IMPL_ID,
+	SBI_MPXY_RPMI_ATTR_IMPL_VERSION,
+	SBI_MPXY_RPMI_ATTR_MAX_ID
+};
+
+/* Encoding of MSG_PROT_VER attribute */
+#define SBI_MPXY_MSG_PROT_VER_MAJOR(__ver)	upper_16_bits(__ver)
+#define SBI_MPXY_MSG_PROT_VER_MINOR(__ver)	lower_16_bits(__ver)
+#define SBI_MPXY_MSG_PROT_MKVER(__maj, __min)	make_u32_from_two_u16(__maj, __min)
+
+/* Capabilities available through CHANNEL_CAPABILITY attribute */
+#define SBI_MPXY_CHAN_CAP_MSI			BIT(0)
+#define SBI_MPXY_CHAN_CAP_SSE			BIT(1)
+#define SBI_MPXY_CHAN_CAP_EVENTS_STATE		BIT(2)
+#define SBI_MPXY_CHAN_CAP_SEND_WITH_RESP	BIT(3)
+#define SBI_MPXY_CHAN_CAP_SEND_WITHOUT_RESP	BIT(4)
+#define SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS	BIT(5)
+
 /* SBI spec version fields */
 #define SBI_SPEC_VERSION_DEFAULT	0x1
 #define SBI_SPEC_VERSION_MAJOR_SHIFT	24
diff --git a/include/linux/wordpart.h b/include/linux/wordpart.h
index 5a7b97bb7c95..ed8717730037 100644
--- a/include/linux/wordpart.h
+++ b/include/linux/wordpart.h
@@ -31,6 +31,14 @@
  */
 #define lower_16_bits(n) ((u16)((n) & 0xffff))
 
+/**
+ * make_u32_from_two_u16 - return u32 number by combining
+ * two u16 numbers.
+ * @hi: upper 16 bit number
+ * @lo: lower 16 bit number
+ */
+#define make_u32_from_two_u16(hi, lo)	(((u32)(hi) << 16) | (u32)(lo))
+
 /**
  * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value
  * @x: value to repeat
-- 
2.43.0

[PATCH v8 04/24] mailbox: Add common header for RPMI messages sent via mailbox

[Anup Patel]

The RPMI based mailbox controller drivers and mailbox clients need to
share defines related to RPMI messages over mailbox interface so add
a common header for this purpose.

Co-developed-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 include/linux/mailbox/riscv-rpmi-message.h | 214 +++++++++++++++++++++
 1 file changed, 214 insertions(+)
 create mode 100644 include/linux/mailbox/riscv-rpmi-message.h

diff --git a/include/linux/mailbox/riscv-rpmi-message.h b/include/linux/mailbox/riscv-rpmi-message.h
new file mode 100644
index 000000000000..3f4c73529aa5
--- /dev/null
+++ b/include/linux/mailbox/riscv-rpmi-message.h
@@ -0,0 +1,214 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2025 Ventana Micro Systems Inc. */
+
+#ifndef _LINUX_RISCV_RPMI_MESSAGE_H_
+#define _LINUX_RISCV_RPMI_MESSAGE_H_
+
+#include <linux/errno.h>
+#include <linux/mailbox_client.h>
+#include <linux/types.h>
+#include <linux/wordpart.h>
+
+/* RPMI version encode/decode macros */
+#define RPMI_VER_MAJOR(__ver)		upper_16_bits(__ver)
+#define RPMI_VER_MINOR(__ver)		lower_16_bits(__ver)
+#define RPMI_MKVER(__maj, __min)	make_u32_from_two_u16(__maj, __min)
+
+/* RPMI message header */
+struct rpmi_message_header {
+	__le16 servicegroup_id;
+	u8 service_id;
+	u8 flags;
+	__le16 datalen;
+	__le16 token;
+};
+
+/* RPMI message */
+struct rpmi_message {
+	struct rpmi_message_header header;
+	u8 data[];
+};
+
+/* RPMI notification event */
+struct rpmi_notification_event {
+	__le16 event_datalen;
+	u8 event_id;
+	u8 reserved;
+	u8 event_data[];
+};
+
+/* RPMI error codes */
+enum rpmi_error_codes {
+	RPMI_SUCCESS			= 0,
+	RPMI_ERR_FAILED			= -1,
+	RPMI_ERR_NOTSUPP		= -2,
+	RPMI_ERR_INVALID_PARAM		= -3,
+	RPMI_ERR_DENIED			= -4,
+	RPMI_ERR_INVALID_ADDR		= -5,
+	RPMI_ERR_ALREADY		= -6,
+	RPMI_ERR_EXTENSION		= -7,
+	RPMI_ERR_HW_FAULT		= -8,
+	RPMI_ERR_BUSY			= -9,
+	RPMI_ERR_INVALID_STATE		= -10,
+	RPMI_ERR_BAD_RANGE		= -11,
+	RPMI_ERR_TIMEOUT		= -12,
+	RPMI_ERR_IO			= -13,
+	RPMI_ERR_NO_DATA		= -14,
+	RPMI_ERR_RESERVED_START		= -15,
+	RPMI_ERR_RESERVED_END		= -127,
+	RPMI_ERR_VENDOR_START		= -128,
+};
+
+static inline int rpmi_to_linux_error(int rpmi_error)
+{
+	switch (rpmi_error) {
+	case RPMI_SUCCESS:
+		return 0;
+	case RPMI_ERR_INVALID_PARAM:
+	case RPMI_ERR_BAD_RANGE:
+	case RPMI_ERR_INVALID_STATE:
+		return -EINVAL;
+	case RPMI_ERR_DENIED:
+		return -EPERM;
+	case RPMI_ERR_INVALID_ADDR:
+	case RPMI_ERR_HW_FAULT:
+		return -EFAULT;
+	case RPMI_ERR_ALREADY:
+		return -EALREADY;
+	case RPMI_ERR_BUSY:
+		return -EBUSY;
+	case RPMI_ERR_TIMEOUT:
+		return -ETIMEDOUT;
+	case RPMI_ERR_IO:
+		return -ECOMM;
+	case RPMI_ERR_FAILED:
+	case RPMI_ERR_NOTSUPP:
+	case RPMI_ERR_NO_DATA:
+	case RPMI_ERR_EXTENSION:
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/* RPMI Linux mailbox attribute IDs */
+enum rpmi_mbox_attribute_id {
+	RPMI_MBOX_ATTR_SPEC_VERSION,
+	RPMI_MBOX_ATTR_MAX_MSG_DATA_SIZE,
+	RPMI_MBOX_ATTR_SERVICEGROUP_ID,
+	RPMI_MBOX_ATTR_SERVICEGROUP_VERSION,
+	RPMI_MBOX_ATTR_IMPL_ID,
+	RPMI_MBOX_ATTR_IMPL_VERSION,
+	RPMI_MBOX_ATTR_MAX_ID
+};
+
+/* RPMI Linux mailbox message types */
+enum rpmi_mbox_message_type {
+	RPMI_MBOX_MSG_TYPE_GET_ATTRIBUTE,
+	RPMI_MBOX_MSG_TYPE_SET_ATTRIBUTE,
+	RPMI_MBOX_MSG_TYPE_SEND_WITH_RESPONSE,
+	RPMI_MBOX_MSG_TYPE_SEND_WITHOUT_RESPONSE,
+	RPMI_MBOX_MSG_TYPE_NOTIFICATION_EVENT,
+	RPMI_MBOX_MSG_MAX_TYPE
+};
+
+/* RPMI Linux mailbox message instance */
+struct rpmi_mbox_message {
+	enum rpmi_mbox_message_type type;
+	union {
+		struct {
+			enum rpmi_mbox_attribute_id id;
+			u32 value;
+		} attr;
+
+		struct {
+			u32 service_id;
+			void *request;
+			unsigned long request_len;
+			void *response;
+			unsigned long max_response_len;
+			unsigned long out_response_len;
+		} data;
+
+		struct {
+			u16 event_datalen;
+			u8 event_id;
+			u8 *event_data;
+		} notif;
+	};
+	int error;
+};
+
+/* RPMI Linux mailbox message helper routines */
+static inline void rpmi_mbox_init_get_attribute(struct rpmi_mbox_message *msg,
+						enum rpmi_mbox_attribute_id id)
+{
+	msg->type = RPMI_MBOX_MSG_TYPE_GET_ATTRIBUTE;
+	msg->attr.id = id;
+	msg->attr.value = 0;
+	msg->error = 0;
+}
+
+static inline void rpmi_mbox_init_set_attribute(struct rpmi_mbox_message *msg,
+						enum rpmi_mbox_attribute_id id,
+						u32 value)
+{
+	msg->type = RPMI_MBOX_MSG_TYPE_SET_ATTRIBUTE;
+	msg->attr.id = id;
+	msg->attr.value = value;
+	msg->error = 0;
+}
+
+static inline void rpmi_mbox_init_send_with_response(struct rpmi_mbox_message *msg,
+						     u32 service_id,
+						     void *request,
+						     unsigned long request_len,
+						     void *response,
+						     unsigned long max_response_len)
+{
+	msg->type = RPMI_MBOX_MSG_TYPE_SEND_WITH_RESPONSE;
+	msg->data.service_id = service_id;
+	msg->data.request = request;
+	msg->data.request_len = request_len;
+	msg->data.response = response;
+	msg->data.max_response_len = max_response_len;
+	msg->data.out_response_len = 0;
+	msg->error = 0;
+}
+
+static inline void rpmi_mbox_init_send_without_response(struct rpmi_mbox_message *msg,
+							u32 service_id,
+							void *request,
+							unsigned long request_len)
+{
+	msg->type = RPMI_MBOX_MSG_TYPE_SEND_WITHOUT_RESPONSE;
+	msg->data.service_id = service_id;
+	msg->data.request = request;
+	msg->data.request_len = request_len;
+	msg->data.response = NULL;
+	msg->data.max_response_len = 0;
+	msg->data.out_response_len = 0;
+	msg->error = 0;
+}
+
+static inline void *rpmi_mbox_get_msg_response(struct rpmi_mbox_message *msg)
+{
+	return msg ? msg->data.response : NULL;
+}
+
+static inline int rpmi_mbox_send_message(struct mbox_chan *chan,
+					 struct rpmi_mbox_message *msg)
+{
+	int ret;
+
+	/* Send message for the underlying mailbox channel */
+	ret = mbox_send_message(chan, msg);
+	if (ret < 0)
+		return ret;
+
+	/* Explicitly signal txdone for mailbox channel */
+	ret = msg->error;
+	mbox_client_txdone(chan, ret);
+	return ret;
+}
+
+#endif /* _LINUX_RISCV_RPMI_MESSAGE_H_ */
-- 
2.43.0

[PATCH v8 05/24] mailbox: Allow controller specific mapping using fwnode

[Anup Patel]

Introduce optional fw_node() callback which allows a mailbox controller
driver to provide controller specific mapping using fwnode.

The Linux OF framework already implements fwnode operations for the
Linux DD framework so the fw_xlate() callback works fine with device
tree as well.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/mailbox/mailbox.c          | 65 ++++++++++++++++++------------
 include/linux/mailbox_controller.h |  3 ++
 2 files changed, 43 insertions(+), 25 deletions(-)

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 5cd8ae222073..2acc6ec229a4 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
+#include <linux/property.h>
 #include <linux/spinlock.h>
 
 #include "mailbox.h"
@@ -383,34 +384,56 @@ EXPORT_SYMBOL_GPL(mbox_bind_client);
  */
 struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
 {
-	struct device *dev = cl->dev;
+	struct fwnode_reference_args fwspec;
+	struct fwnode_handle *fwnode;
 	struct mbox_controller *mbox;
 	struct of_phandle_args spec;
 	struct mbox_chan *chan;
+	struct device *dev;
+	unsigned int i;
 	int ret;
 
-	if (!dev || !dev->of_node) {
-		pr_debug("%s: No owner device node\n", __func__);
+	dev = cl->dev;
+	if (!dev) {
+		pr_debug("No owner device\n");
 		return ERR_PTR(-ENODEV);
 	}
 
-	ret = of_parse_phandle_with_args(dev->of_node, "mboxes", "#mbox-cells",
-					 index, &spec);
+	fwnode = dev_fwnode(dev);
+	if (!fwnode) {
+		dev_dbg(dev, "No owner fwnode\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	ret = fwnode_property_get_reference_args(fwnode, "mboxes", "#mbox-cells",
+						 0, index, &fwspec);
 	if (ret) {
-		dev_err(dev, "%s: can't parse \"mboxes\" property\n", __func__);
+		dev_err(dev, "%s: can't parse \"%s\" property\n", __func__, "mboxes");
 		return ERR_PTR(ret);
 	}
 
+	spec.np = to_of_node(fwspec.fwnode);
+	spec.args_count = fwspec.nargs;
+	for (i = 0; i < spec.args_count; i++)
+		spec.args[i] = fwspec.args[i];
+
 	scoped_guard(mutex, &con_mutex) {
 		chan = ERR_PTR(-EPROBE_DEFER);
-		list_for_each_entry(mbox, &mbox_cons, node)
-			if (mbox->dev->of_node == spec.np) {
-				chan = mbox->of_xlate(mbox, &spec);
-				if (!IS_ERR(chan))
-					break;
+		list_for_each_entry(mbox, &mbox_cons, node) {
+			if (device_match_fwnode(mbox->dev, fwspec.fwnode)) {
+				if (mbox->fw_xlate) {
+					chan = mbox->fw_xlate(mbox, &fwspec);
+					if (!IS_ERR(chan))
+						break;
+				} else if (mbox->of_xlate) {
+					chan = mbox->of_xlate(mbox, &spec);
+					if (!IS_ERR(chan))
+						break;
+				}
 			}
+		}
 
-		of_node_put(spec.np);
+		fwnode_handle_put(fwspec.fwnode);
 
 		if (IS_ERR(chan))
 			return chan;
@@ -427,15 +450,8 @@ EXPORT_SYMBOL_GPL(mbox_request_channel);
 struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
 					      const char *name)
 {
-	struct device_node *np = cl->dev->of_node;
-	int index;
-
-	if (!np) {
-		dev_err(cl->dev, "%s() currently only supports DT\n", __func__);
-		return ERR_PTR(-EINVAL);
-	}
+	int index = device_property_match_string(cl->dev, "mbox-names", name);
 
-	index = of_property_match_string(np, "mbox-names", name);
 	if (index < 0) {
 		dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
 			__func__, name);
@@ -470,9 +486,8 @@ void mbox_free_channel(struct mbox_chan *chan)
 }
 EXPORT_SYMBOL_GPL(mbox_free_channel);
 
-static struct mbox_chan *
-of_mbox_index_xlate(struct mbox_controller *mbox,
-		    const struct of_phandle_args *sp)
+static struct mbox_chan *fw_mbox_index_xlate(struct mbox_controller *mbox,
+					     const struct fwnode_reference_args *sp)
 {
 	int ind = sp->args[0];
 
@@ -523,8 +538,8 @@ int mbox_controller_register(struct mbox_controller *mbox)
 		spin_lock_init(&chan->lock);
 	}
 
-	if (!mbox->of_xlate)
-		mbox->of_xlate = of_mbox_index_xlate;
+	if (!mbox->fw_xlate && !mbox->of_xlate)
+		mbox->fw_xlate = fw_mbox_index_xlate;
 
 	scoped_guard(mutex, &con_mutex)
 		list_add_tail(&mbox->node, &mbox_cons);
diff --git a/include/linux/mailbox_controller.h b/include/linux/mailbox_controller.h
index ad01c4082358..80a427c7ca29 100644
--- a/include/linux/mailbox_controller.h
+++ b/include/linux/mailbox_controller.h
@@ -66,6 +66,7 @@ struct mbox_chan_ops {
  *			no interrupt rises. Ignored if 'txdone_irq' is set.
  * @txpoll_period:	If 'txdone_poll' is in effect, the API polls for
  *			last TX's status after these many millisecs
+ * @fw_xlate:		Controller driver specific mapping of channel via fwnode
  * @of_xlate:		Controller driver specific mapping of channel via DT
  * @poll_hrt:		API private. hrtimer used to poll for TXDONE on all
  *			channels.
@@ -79,6 +80,8 @@ struct mbox_controller {
 	bool txdone_irq;
 	bool txdone_poll;
 	unsigned txpoll_period;
+	struct mbox_chan *(*fw_xlate)(struct mbox_controller *mbox,
+				      const struct fwnode_reference_args *sp);
 	struct mbox_chan *(*of_xlate)(struct mbox_controller *mbox,
 				      const struct of_phandle_args *sp);
 	/* Internal to API */
-- 
2.43.0

[PATCH v8 06/24] byteorder: Add memcpy_to_le32() and memcpy_from_le32()

[Anup Patel]

Add common memcpy APIs for copying u32 array to/from __le32 array.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 include/linux/byteorder/generic.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/linux/byteorder/generic.h b/include/linux/byteorder/generic.h
index c9a4c96c9943..b3705e8bbe2b 100644
--- a/include/linux/byteorder/generic.h
+++ b/include/linux/byteorder/generic.h
@@ -173,6 +173,22 @@ static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
 	}
 }
 
+static inline void memcpy_from_le32(u32 *dst, const __le32 *src, size_t words)
+{
+	size_t i;
+
+	for (i = 0; i < words; i++)
+		dst[i] = le32_to_cpu(src[i]);
+}
+
+static inline void memcpy_to_le32(__le32 *dst, const u32 *src, size_t words)
+{
+	size_t i;
+
+	for (i = 0; i < words; i++)
+		dst[i] = cpu_to_le32(src[i]);
+}
+
 static inline void be16_add_cpu(__be16 *var, u16 val)
 {
 	*var = cpu_to_be16(be16_to_cpu(*var) + val);
-- 
2.43.0

[PATCH v8 07/24] mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver

[Anup Patel]

Add a mailbox controller driver for the new SBI message proxy extension
which is part of the SBI v3.0 specification.

Co-developed-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/mailbox/Kconfig               |  11 +
 drivers/mailbox/Makefile              |   2 +
 drivers/mailbox/riscv-sbi-mpxy-mbox.c | 992 ++++++++++++++++++++++++++
 3 files changed, 1005 insertions(+)
 create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c

diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 68eeed660a4a..eb5e0384fec6 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -340,4 +340,15 @@ config THEAD_TH1520_MBOX
 	  kernel is running, and E902 core used for power management among other
 	  things.
 
+config RISCV_SBI_MPXY_MBOX
+	tristate "RISC-V SBI Message Proxy (MPXY) Mailbox"
+	depends on RISCV_SBI
+	default RISCV
+	help
+	  Mailbox driver implementation for RISC-V SBI Message Proxy (MPXY)
+	  extension. This mailbox driver is used to send messages to the
+	  remote processor through the SBI implementation (M-mode firmware
+	  or HS-mode hypervisor). Say Y here if you want to have this support.
+	  If unsure say N.
+
 endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 13a3448b3271..46689c1277f8 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -72,3 +72,5 @@ obj-$(CONFIG_QCOM_CPUCP_MBOX)	+= qcom-cpucp-mbox.o
 obj-$(CONFIG_QCOM_IPCC)		+= qcom-ipcc.o
 
 obj-$(CONFIG_THEAD_TH1520_MBOX)	+= mailbox-th1520.o
+
+obj-$(CONFIG_RISCV_SBI_MPXY_MBOX)	+= riscv-sbi-mpxy-mbox.o
diff --git a/drivers/mailbox/riscv-sbi-mpxy-mbox.c b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
new file mode 100644
index 000000000000..1a8a74d3ad4b
--- /dev/null
+++ b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
@@ -0,0 +1,992 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RISC-V SBI Message Proxy (MPXY) mailbox controller driver
+ *
+ * Copyright (C) 2025 Ventana Micro Systems Inc.
+ */
+
+#include <linux/cpu.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox/riscv-rpmi-message.h>
+#include <linux/minmax.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/percpu.h>
+#include <linux/platform_device.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <asm/byteorder.h>
+#include <asm/sbi.h>
+
+/* ====== SBI MPXY extension data structures ====== */
+
+/* SBI MPXY MSI related channel attributes */
+struct sbi_mpxy_msi_info {
+	/* Lower 32-bits of the MSI target address */
+	u32 msi_addr_lo;
+	/* Upper 32-bits of the MSI target address */
+	u32 msi_addr_hi;
+	/* MSI data value */
+	u32 msi_data;
+};
+
+/*
+ * SBI MPXY standard channel attributes.
+ *
+ * NOTE: The sequence of attribute fields are as-per the
+ * defined sequence in the attribute table in spec (or
+ * as-per the enum sbi_mpxy_attribute_id).
+ */
+struct sbi_mpxy_channel_attrs {
+	/* Message protocol ID */
+	u32 msg_proto_id;
+	/* Message protocol version */
+	u32 msg_proto_version;
+	/* Message protocol maximum message length */
+	u32 msg_max_len;
+	/* Message protocol message send timeout in microseconds */
+	u32 msg_send_timeout;
+	/* Message protocol message completion timeout in microseconds */
+	u32 msg_completion_timeout;
+	/* Bit array for channel capabilities */
+	u32 capability;
+	/* SSE event ID */
+	u32 sse_event_id;
+	/* MSI enable/disable control knob */
+	u32 msi_control;
+	/* Channel MSI info */
+	struct sbi_mpxy_msi_info msi_info;
+	/* Events state control */
+	u32 events_state_ctrl;
+};
+
+/*
+ * RPMI specific SBI MPXY channel attributes.
+ *
+ * NOTE: The sequence of attribute fields are as-per the
+ * defined sequence in the attribute table in spec (or
+ * as-per the enum sbi_mpxy_rpmi_attribute_id).
+ */
+struct sbi_mpxy_rpmi_channel_attrs {
+	/* RPMI service group ID */
+	u32 servicegroup_id;
+	/* RPMI service group version */
+	u32 servicegroup_version;
+	/* RPMI implementation ID */
+	u32 impl_id;
+	/* RPMI implementation version */
+	u32 impl_version;
+};
+
+/* SBI MPXY channel IDs data in shared memory */
+struct sbi_mpxy_channel_ids_data {
+	/* Remaining number of channel ids */
+	__le32 remaining;
+	/* Returned channel ids in current function call */
+	__le32 returned;
+	/* Returned channel id array */
+	__le32 channel_array[];
+};
+
+/* SBI MPXY notification data in shared memory */
+struct sbi_mpxy_notification_data {
+	/* Remaining number of notification events */
+	__le32 remaining;
+	/* Number of notification events returned */
+	__le32 returned;
+	/* Number of notification events lost */
+	__le32 lost;
+	/* Reserved for future use */
+	__le32 reserved;
+	/* Returned channel id array */
+	u8 events_data[];
+};
+
+/* ====== MPXY data structures & helper routines ====== */
+
+/* MPXY Per-CPU or local context */
+struct mpxy_local {
+	/* Shared memory base address */
+	void *shmem;
+	/* Shared memory physical address */
+	phys_addr_t shmem_phys_addr;
+	/* Flag representing whether shared memory is active or not */
+	bool shmem_active;
+};
+
+static DEFINE_PER_CPU(struct mpxy_local, mpxy_local);
+static unsigned long mpxy_shmem_size;
+static bool mpxy_shmem_init_done;
+
+static int mpxy_get_channel_count(u32 *channel_count)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbi_mpxy_channel_ids_data *sdata = mpxy->shmem;
+	u32 remaining, returned;
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!channel_count)
+		return -EINVAL;
+
+	get_cpu();
+
+	/* Get the remaining and returned fields to calculate total */
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_CHANNEL_IDS,
+			 0, 0, 0, 0, 0, 0);
+	if (sret.error)
+		goto err_put_cpu;
+
+	remaining = le32_to_cpu(sdata->remaining);
+	returned = le32_to_cpu(sdata->returned);
+	*channel_count = remaining + returned;
+
+err_put_cpu:
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_get_channel_ids(u32 channel_count, u32 *channel_ids)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbi_mpxy_channel_ids_data *sdata = mpxy->shmem;
+	u32 remaining, returned, count, start_index = 0;
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!channel_count || !channel_ids)
+		return -EINVAL;
+
+	get_cpu();
+
+	do {
+		sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_CHANNEL_IDS,
+				 start_index, 0, 0, 0, 0, 0);
+		if (sret.error)
+			goto err_put_cpu;
+
+		remaining = le32_to_cpu(sdata->remaining);
+		returned = le32_to_cpu(sdata->returned);
+
+		count = returned < (channel_count - start_index) ?
+			returned : (channel_count - start_index);
+		memcpy_from_le32(&channel_ids[start_index], sdata->channel_array, count);
+		start_index += count;
+	} while (remaining && start_index < channel_count);
+
+err_put_cpu:
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_read_attrs(u32 channel_id, u32 base_attrid, u32 attr_count,
+			   u32 *attrs_buf)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!attr_count || !attrs_buf)
+		return -EINVAL;
+
+	get_cpu();
+
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_READ_ATTRS,
+			 channel_id, base_attrid, attr_count, 0, 0, 0);
+	if (sret.error)
+		goto err_put_cpu;
+
+	memcpy_from_le32(attrs_buf, (__le32 *)mpxy->shmem, attr_count);
+
+err_put_cpu:
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_write_attrs(u32 channel_id, u32 base_attrid, u32 attr_count,
+			    u32 *attrs_buf)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!attr_count || !attrs_buf)
+		return -EINVAL;
+
+	get_cpu();
+
+	memcpy_to_le32((__le32 *)mpxy->shmem, attrs_buf, attr_count);
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_WRITE_ATTRS,
+			 channel_id, base_attrid, attr_count, 0, 0, 0);
+
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_send_message_with_resp(u32 channel_id, u32 msg_id,
+				       void *tx, unsigned long tx_len,
+				       void *rx, unsigned long max_rx_len,
+				       unsigned long *rx_len)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	unsigned long rx_bytes;
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!tx && tx_len)
+		return -EINVAL;
+
+	get_cpu();
+
+	/* Message protocols allowed to have no data in messages */
+	if (tx_len)
+		memcpy(mpxy->shmem, tx, tx_len);
+
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SEND_MSG_WITH_RESP,
+			 channel_id, msg_id, tx_len, 0, 0, 0);
+	if (rx && !sret.error) {
+		rx_bytes = sret.value;
+		if (rx_bytes > max_rx_len) {
+			put_cpu();
+			return -ENOSPC;
+		}
+
+		memcpy(rx, mpxy->shmem, rx_bytes);
+		if (rx_len)
+			*rx_len = rx_bytes;
+	}
+
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_send_message_without_resp(u32 channel_id, u32 msg_id,
+					  void *tx, unsigned long tx_len)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!tx && tx_len)
+		return -EINVAL;
+
+	get_cpu();
+
+	/* Message protocols allowed to have no data in messages */
+	if (tx_len)
+		memcpy(mpxy->shmem, tx, tx_len);
+
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SEND_MSG_WITHOUT_RESP,
+			 channel_id, msg_id, tx_len, 0, 0, 0);
+
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_get_notifications(u32 channel_id,
+				  struct sbi_mpxy_notification_data *notif_data,
+				  unsigned long *events_data_len)
+{
+	struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local);
+	struct sbiret sret;
+
+	if (!mpxy->shmem_active)
+		return -ENODEV;
+	if (!notif_data || !events_data_len)
+		return -EINVAL;
+
+	get_cpu();
+
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_NOTIFICATION_EVENTS,
+			 channel_id, 0, 0, 0, 0, 0);
+	if (sret.error)
+		goto err_put_cpu;
+
+	memcpy(notif_data, mpxy->shmem, sret.value + 16);
+	*events_data_len = sret.value;
+
+err_put_cpu:
+	put_cpu();
+	return sbi_err_map_linux_errno(sret.error);
+}
+
+static int mpxy_get_shmem_size(unsigned long *shmem_size)
+{
+	struct sbiret sret;
+
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_SHMEM_SIZE,
+			 0, 0, 0, 0, 0, 0);
+	if (sret.error)
+		return sbi_err_map_linux_errno(sret.error);
+	if (shmem_size)
+		*shmem_size = sret.value;
+	return 0;
+}
+
+static int mpxy_setup_shmem(unsigned int cpu)
+{
+	struct page *shmem_page;
+	struct mpxy_local *mpxy;
+	struct sbiret sret;
+
+	mpxy = per_cpu_ptr(&mpxy_local, cpu);
+	if (mpxy->shmem_active)
+		return 0;
+
+	shmem_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(mpxy_shmem_size));
+	if (!shmem_page)
+		return -ENOMEM;
+
+	/*
+	 * Linux setup of shmem is done in mpxy OVERWRITE mode.
+	 * flags[1:0] = 00b
+	 */
+	sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SET_SHMEM,
+			 page_to_phys(shmem_page), 0, 0, 0, 0, 0);
+	if (sret.error) {
+		free_pages((unsigned long)page_to_virt(shmem_page),
+			   get_order(mpxy_shmem_size));
+		return sbi_err_map_linux_errno(sret.error);
+	}
+
+	mpxy->shmem = page_to_virt(shmem_page);
+	mpxy->shmem_phys_addr = page_to_phys(shmem_page);
+	mpxy->shmem_active = true;
+
+	return 0;
+}
+
+/* ====== MPXY mailbox data structures ====== */
+
+/* MPXY mailbox channel */
+struct mpxy_mbox_channel {
+	struct mpxy_mbox *mbox;
+	u32 channel_id;
+	struct sbi_mpxy_channel_attrs attrs;
+	struct sbi_mpxy_rpmi_channel_attrs rpmi_attrs;
+	struct sbi_mpxy_notification_data *notif;
+	u32 max_xfer_len;
+	bool have_events_state;
+	u32 msi_index;
+	u32 msi_irq;
+	bool started;
+};
+
+/* MPXY mailbox */
+struct mpxy_mbox {
+	struct device *dev;
+	u32 channel_count;
+	struct mpxy_mbox_channel *channels;
+	u32 msi_count;
+	struct mpxy_mbox_channel **msi_index_to_channel;
+	struct mbox_controller controller;
+};
+
+/* ====== MPXY RPMI processing ====== */
+
+static void mpxy_mbox_send_rpmi_data(struct mpxy_mbox_channel *mchan,
+				     struct rpmi_mbox_message *msg)
+{
+	msg->error = 0;
+	switch (msg->type) {
+	case RPMI_MBOX_MSG_TYPE_GET_ATTRIBUTE:
+		switch (msg->attr.id) {
+		case RPMI_MBOX_ATTR_SPEC_VERSION:
+			msg->attr.value = mchan->attrs.msg_proto_version;
+			break;
+		case RPMI_MBOX_ATTR_MAX_MSG_DATA_SIZE:
+			msg->attr.value = mchan->max_xfer_len;
+			break;
+		case RPMI_MBOX_ATTR_SERVICEGROUP_ID:
+			msg->attr.value = mchan->rpmi_attrs.servicegroup_id;
+			break;
+		case RPMI_MBOX_ATTR_SERVICEGROUP_VERSION:
+			msg->attr.value = mchan->rpmi_attrs.servicegroup_version;
+			break;
+		case RPMI_MBOX_ATTR_IMPL_ID:
+			msg->attr.value = mchan->rpmi_attrs.impl_id;
+			break;
+		case RPMI_MBOX_ATTR_IMPL_VERSION:
+			msg->attr.value = mchan->rpmi_attrs.impl_version;
+			break;
+		default:
+			msg->error = -EOPNOTSUPP;
+			break;
+		}
+		break;
+	case RPMI_MBOX_MSG_TYPE_SET_ATTRIBUTE:
+		/* None of the RPMI linux mailbox attributes are writeable */
+		msg->error = -EOPNOTSUPP;
+		break;
+	case RPMI_MBOX_MSG_TYPE_SEND_WITH_RESPONSE:
+		if ((!msg->data.request && msg->data.request_len) ||
+		    (msg->data.request && msg->data.request_len > mchan->max_xfer_len) ||
+		    (!msg->data.response && msg->data.max_response_len)) {
+			msg->error = -EINVAL;
+			break;
+		}
+		if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_SEND_WITH_RESP)) {
+			msg->error = -EIO;
+			break;
+		}
+		msg->error = mpxy_send_message_with_resp(mchan->channel_id,
+							 msg->data.service_id,
+							 msg->data.request,
+							 msg->data.request_len,
+							 msg->data.response,
+							 msg->data.max_response_len,
+							 &msg->data.out_response_len);
+		break;
+	case RPMI_MBOX_MSG_TYPE_SEND_WITHOUT_RESPONSE:
+		if ((!msg->data.request && msg->data.request_len) ||
+		    (msg->data.request && msg->data.request_len > mchan->max_xfer_len)) {
+			msg->error = -EINVAL;
+			break;
+		}
+		if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_SEND_WITHOUT_RESP)) {
+			msg->error = -EIO;
+			break;
+		}
+		msg->error = mpxy_send_message_without_resp(mchan->channel_id,
+							    msg->data.service_id,
+							    msg->data.request,
+							    msg->data.request_len);
+		break;
+	default:
+		msg->error = -EOPNOTSUPP;
+		break;
+	}
+}
+
+static void mpxy_mbox_peek_rpmi_data(struct mbox_chan *chan,
+				     struct mpxy_mbox_channel *mchan,
+				     struct sbi_mpxy_notification_data *notif,
+				     unsigned long events_data_len)
+{
+	struct rpmi_notification_event *event;
+	struct rpmi_mbox_message msg;
+	unsigned long pos = 0;
+
+	while (pos < events_data_len && (events_data_len - pos) <= sizeof(*event)) {
+		event = (struct rpmi_notification_event *)(notif->events_data + pos);
+
+		msg.type = RPMI_MBOX_MSG_TYPE_NOTIFICATION_EVENT;
+		msg.notif.event_datalen = le16_to_cpu(event->event_datalen);
+		msg.notif.event_id = event->event_id;
+		msg.notif.event_data = event->event_data;
+		msg.error = 0;
+
+		mbox_chan_received_data(chan, &msg);
+		pos += sizeof(*event) + msg.notif.event_datalen;
+	}
+}
+
+static int mpxy_mbox_read_rpmi_attrs(struct mpxy_mbox_channel *mchan)
+{
+	return mpxy_read_attrs(mchan->channel_id,
+			       SBI_MPXY_ATTR_MSGPROTO_ATTR_START,
+			       sizeof(mchan->rpmi_attrs) / sizeof(u32),
+			       (u32 *)&mchan->rpmi_attrs);
+}
+
+/* ====== MPXY mailbox callbacks ====== */
+
+static int mpxy_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+	struct mpxy_mbox_channel *mchan = chan->con_priv;
+
+	if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID) {
+		mpxy_mbox_send_rpmi_data(mchan, data);
+		return 0;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static bool mpxy_mbox_peek_data(struct mbox_chan *chan)
+{
+	struct mpxy_mbox_channel *mchan = chan->con_priv;
+	struct sbi_mpxy_notification_data *notif = mchan->notif;
+	bool have_notifications = false;
+	unsigned long data_len;
+	int rc;
+
+	if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS))
+		return false;
+
+	do {
+		rc = mpxy_get_notifications(mchan->channel_id, notif, &data_len);
+		if (rc || !data_len)
+			break;
+
+		if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID)
+			mpxy_mbox_peek_rpmi_data(chan, mchan, notif, data_len);
+
+		have_notifications = true;
+	} while (1);
+
+	return have_notifications;
+}
+
+static irqreturn_t mpxy_mbox_irq_thread(int irq, void *dev_id)
+{
+	mpxy_mbox_peek_data(dev_id);
+	return IRQ_HANDLED;
+}
+
+static int mpxy_mbox_setup_msi(struct mbox_chan *chan,
+			       struct mpxy_mbox_channel *mchan)
+{
+	struct device *dev = mchan->mbox->dev;
+	int rc;
+
+	/* Do nothing if MSI not supported */
+	if (mchan->msi_irq == U32_MAX)
+		return 0;
+
+	/* Fail if MSI already enabled */
+	if (mchan->attrs.msi_control)
+		return -EALREADY;
+
+	/* Request channel MSI handler */
+	rc = request_threaded_irq(mchan->msi_irq, NULL, mpxy_mbox_irq_thread,
+				  0, dev_name(dev), chan);
+	if (rc) {
+		dev_err(dev, "failed to request MPXY channel 0x%x IRQ\n",
+			mchan->channel_id);
+		return rc;
+	}
+
+	/* Enable channel MSI control */
+	mchan->attrs.msi_control = 1;
+	rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_CONTROL,
+			      1, &mchan->attrs.msi_control);
+	if (rc) {
+		dev_err(dev, "enable MSI control failed for MPXY channel 0x%x\n",
+			mchan->channel_id);
+		mchan->attrs.msi_control = 0;
+		free_irq(mchan->msi_irq, chan);
+		return rc;
+	}
+
+	return 0;
+}
+
+static void mpxy_mbox_cleanup_msi(struct mbox_chan *chan,
+				  struct mpxy_mbox_channel *mchan)
+{
+	struct device *dev = mchan->mbox->dev;
+	int rc;
+
+	/* Do nothing if MSI not supported */
+	if (mchan->msi_irq == U32_MAX)
+		return;
+
+	/* Do nothing if MSI already disabled */
+	if (!mchan->attrs.msi_control)
+		return;
+
+	/* Disable channel MSI control */
+	mchan->attrs.msi_control = 0;
+	rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_CONTROL,
+			      1, &mchan->attrs.msi_control);
+	if (rc) {
+		dev_err(dev, "disable MSI control failed for MPXY channel 0x%x\n",
+			mchan->channel_id);
+	}
+
+	/* Free channel MSI handler */
+	free_irq(mchan->msi_irq, chan);
+}
+
+static int mpxy_mbox_setup_events(struct mpxy_mbox_channel *mchan)
+{
+	struct device *dev = mchan->mbox->dev;
+	int rc;
+
+	/* Do nothing if events state not supported */
+	if (!mchan->have_events_state)
+		return 0;
+
+	/* Fail if events state already enabled */
+	if (mchan->attrs.events_state_ctrl)
+		return -EALREADY;
+
+	/* Enable channel events state */
+	mchan->attrs.events_state_ctrl = 1;
+	rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_EVENTS_STATE_CONTROL,
+			      1, &mchan->attrs.events_state_ctrl);
+	if (rc) {
+		dev_err(dev, "enable events state failed for MPXY channel 0x%x\n",
+			mchan->channel_id);
+		mchan->attrs.events_state_ctrl = 0;
+		return rc;
+	}
+
+	return 0;
+}
+
+static void mpxy_mbox_cleanup_events(struct mpxy_mbox_channel *mchan)
+{
+	struct device *dev = mchan->mbox->dev;
+	int rc;
+
+	/* Do nothing if events state not supported */
+	if (!mchan->have_events_state)
+		return;
+
+	/* Do nothing if events state already disabled */
+	if (!mchan->attrs.events_state_ctrl)
+		return;
+
+	/* Disable channel events state */
+	mchan->attrs.events_state_ctrl = 0;
+	rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_EVENTS_STATE_CONTROL,
+			      1, &mchan->attrs.events_state_ctrl);
+	if (rc)
+		dev_err(dev, "disable events state failed for MPXY channel 0x%x\n",
+			mchan->channel_id);
+}
+
+static int mpxy_mbox_startup(struct mbox_chan *chan)
+{
+	struct mpxy_mbox_channel *mchan = chan->con_priv;
+	int rc;
+
+	if (mchan->started)
+		return -EALREADY;
+
+	/* Setup channel MSI */
+	rc = mpxy_mbox_setup_msi(chan, mchan);
+	if (rc)
+		return rc;
+
+	/* Setup channel notification events */
+	rc = mpxy_mbox_setup_events(mchan);
+	if (rc) {
+		mpxy_mbox_cleanup_msi(chan, mchan);
+		return rc;
+	}
+
+	/* Mark the channel as started */
+	mchan->started = true;
+
+	return 0;
+}
+
+static void mpxy_mbox_shutdown(struct mbox_chan *chan)
+{
+	struct mpxy_mbox_channel *mchan = chan->con_priv;
+
+	if (!mchan->started)
+		return;
+
+	/* Mark the channel as stopped */
+	mchan->started = false;
+
+	/* Cleanup channel notification events */
+	mpxy_mbox_cleanup_events(mchan);
+
+	/* Cleanup channel MSI */
+	mpxy_mbox_cleanup_msi(chan, mchan);
+}
+
+static const struct mbox_chan_ops mpxy_mbox_ops = {
+	.send_data = mpxy_mbox_send_data,
+	.peek_data = mpxy_mbox_peek_data,
+	.startup = mpxy_mbox_startup,
+	.shutdown = mpxy_mbox_shutdown,
+};
+
+/* ====== MPXY platform driver ===== */
+
+static void mpxy_mbox_msi_write(struct msi_desc *desc, struct msi_msg *msg)
+{
+	struct device *dev = msi_desc_to_dev(desc);
+	struct mpxy_mbox *mbox = dev_get_drvdata(dev);
+	struct mpxy_mbox_channel *mchan;
+	struct sbi_mpxy_msi_info *minfo;
+	int rc;
+
+	mchan = mbox->msi_index_to_channel[desc->msi_index];
+	if (!mchan) {
+		dev_warn(dev, "MPXY channel not available for MSI index %d\n",
+			 desc->msi_index);
+		return;
+	}
+
+	minfo = &mchan->attrs.msi_info;
+	minfo->msi_addr_lo = msg->address_lo;
+	minfo->msi_addr_hi = msg->address_hi;
+	minfo->msi_data = msg->data;
+
+	rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_ADDR_LO,
+			      sizeof(*minfo) / sizeof(u32), (u32 *)minfo);
+	if (rc) {
+		dev_warn(dev, "failed to write MSI info for MPXY channel 0x%x\n",
+			 mchan->channel_id);
+	}
+}
+
+static struct mbox_chan *mpxy_mbox_fw_xlate(struct mbox_controller *ctlr,
+					    const struct fwnode_reference_args *pa)
+{
+	struct mpxy_mbox *mbox = container_of(ctlr, struct mpxy_mbox, controller);
+	struct mpxy_mbox_channel *mchan;
+	u32 i;
+
+	if (pa->nargs != 2)
+		return ERR_PTR(-EINVAL);
+
+	for (i = 0; i < mbox->channel_count; i++) {
+		mchan = &mbox->channels[i];
+		if (mchan->channel_id == pa->args[0] &&
+		    mchan->attrs.msg_proto_id == pa->args[1])
+			return &mbox->controller.chans[i];
+	}
+
+	return ERR_PTR(-ENOENT);
+}
+
+static int mpxy_mbox_populate_channels(struct mpxy_mbox *mbox)
+{
+	u32 i, *channel_ids __free(kfree) = NULL;
+	struct mpxy_mbox_channel *mchan;
+	int rc;
+
+	/* Find-out of number of channels */
+	rc = mpxy_get_channel_count(&mbox->channel_count);
+	if (rc)
+		return dev_err_probe(mbox->dev, rc, "failed to get number of MPXY channels\n");
+	if (!mbox->channel_count)
+		return dev_err_probe(mbox->dev, -ENODEV, "no MPXY channels available\n");
+
+	/* Allocate and fetch all channel IDs */
+	channel_ids = kcalloc(mbox->channel_count, sizeof(*channel_ids), GFP_KERNEL);
+	if (!channel_ids)
+		return -ENOMEM;
+	rc = mpxy_get_channel_ids(mbox->channel_count, channel_ids);
+	if (rc)
+		return dev_err_probe(mbox->dev, rc, "failed to get MPXY channel IDs\n");
+
+	/* Populate all channels */
+	mbox->channels = devm_kcalloc(mbox->dev, mbox->channel_count,
+				      sizeof(*mbox->channels), GFP_KERNEL);
+	if (!mbox->channels)
+		return -ENOMEM;
+	for (i = 0; i < mbox->channel_count; i++) {
+		mchan = &mbox->channels[i];
+		mchan->mbox = mbox;
+		mchan->channel_id = channel_ids[i];
+
+		rc = mpxy_read_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSG_PROT_ID,
+				     sizeof(mchan->attrs) / sizeof(u32),
+				     (u32 *)&mchan->attrs);
+		if (rc) {
+			return dev_err_probe(mbox->dev, rc,
+					     "MPXY channel 0x%x read attrs failed\n",
+					     mchan->channel_id);
+		}
+
+		if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID) {
+			rc = mpxy_mbox_read_rpmi_attrs(mchan);
+			if (rc) {
+				return dev_err_probe(mbox->dev, rc,
+						     "MPXY channel 0x%x read RPMI attrs failed\n",
+						     mchan->channel_id);
+			}
+		}
+
+		mchan->notif = devm_kzalloc(mbox->dev, mpxy_shmem_size, GFP_KERNEL);
+		if (!mchan->notif)
+			return -ENOMEM;
+
+		mchan->max_xfer_len = min(mpxy_shmem_size, mchan->attrs.msg_max_len);
+
+		if ((mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS) &&
+		    (mchan->attrs.capability & SBI_MPXY_CHAN_CAP_EVENTS_STATE))
+			mchan->have_events_state = true;
+
+		if ((mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS) &&
+		    (mchan->attrs.capability & SBI_MPXY_CHAN_CAP_MSI))
+			mchan->msi_index = mbox->msi_count++;
+		else
+			mchan->msi_index = U32_MAX;
+		mchan->msi_irq = U32_MAX;
+	}
+
+	return 0;
+}
+
+static int mpxy_mbox_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mpxy_mbox_channel *mchan;
+	struct mpxy_mbox *mbox;
+	int msi_idx, rc;
+	u32 i;
+
+	/*
+	 * Initialize MPXY shared memory only once. This also ensures
+	 * that SBI MPXY mailbox is probed only once.
+	 */
+	if (mpxy_shmem_init_done) {
+		dev_err(dev, "SBI MPXY mailbox already initialized\n");
+		return -EALREADY;
+	}
+
+	/* Probe for SBI MPXY extension */
+	if (sbi_spec_version < sbi_mk_version(1, 0) ||
+	    sbi_probe_extension(SBI_EXT_MPXY) <= 0) {
+		dev_info(dev, "SBI MPXY extension not available\n");
+		return -ENODEV;
+	}
+
+	/* Find-out shared memory size */
+	rc = mpxy_get_shmem_size(&mpxy_shmem_size);
+	if (rc)
+		return dev_err_probe(dev, rc, "failed to get MPXY shared memory size\n");
+
+	/*
+	 * Setup MPXY shared memory on each CPU
+	 *
+	 * Note: Don't cleanup MPXY shared memory upon CPU power-down
+	 * because the RPMI System MSI irqchip driver needs it to be
+	 * available when migrating IRQs in CPU power-down path.
+	 */
+	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/sbi-mpxy-shmem",
+			  mpxy_setup_shmem, NULL);
+
+	/* Mark as MPXY shared memory initialization done */
+	mpxy_shmem_init_done = true;
+
+	/* Allocate mailbox instance */
+	mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
+	if (!mbox)
+		return -ENOMEM;
+	mbox->dev = dev;
+	platform_set_drvdata(pdev, mbox);
+
+	/* Populate mailbox channels */
+	rc = mpxy_mbox_populate_channels(mbox);
+
+	/* Initialize mailbox controller */
+	mbox->controller.txdone_irq = false;
+	mbox->controller.txdone_poll = false;
+	mbox->controller.ops = &mpxy_mbox_ops;
+	mbox->controller.dev = dev;
+	mbox->controller.num_chans = mbox->channel_count;
+	mbox->controller.fw_xlate = mpxy_mbox_fw_xlate;
+	mbox->controller.chans = devm_kcalloc(dev, mbox->channel_count,
+					      sizeof(*mbox->controller.chans),
+					      GFP_KERNEL);
+	if (!mbox->controller.chans)
+		return -ENOMEM;
+	for (i = 0; i < mbox->channel_count; i++)
+		mbox->controller.chans[i].con_priv = &mbox->channels[i];
+
+	/*
+	 * The device MSI domain for platform devices on RISC-V architecture
+	 * is only available after the MSI controller driver is probed so,
+	 * explicitly configure here.
+	 */
+	if (!dev_get_msi_domain(dev)) {
+		/*
+		 * The device MSI domain for OF devices is only set at the
+		 * time of populating/creating OF device. If the device MSI
+		 * domain is discovered later after the OF device is created
+		 * then we need to set it explicitly before using any platform
+		 * MSI functions.
+		 */
+		if (dev_of_node(dev))
+			of_msi_configure(dev, dev_of_node(dev));
+
+		if (!dev_get_msi_domain(dev))
+			return -EPROBE_DEFER;
+	}
+
+	/* Setup MSIs for mailbox (if required) */
+	if (mbox->msi_count) {
+		mbox->msi_index_to_channel = devm_kcalloc(dev, mbox->msi_count,
+							  sizeof(*mbox->msi_index_to_channel),
+							  GFP_KERNEL);
+		if (!mbox->msi_index_to_channel)
+			return -ENOMEM;
+
+		for (msi_idx = 0; msi_idx < mbox->msi_count; msi_idx++) {
+			for (i = 0; i < mbox->channel_count; i++) {
+				mchan = &mbox->channels[i];
+				if (mchan->msi_index == msi_idx) {
+					mbox->msi_index_to_channel[msi_idx] = mchan;
+					break;
+				}
+			}
+		}
+
+		rc = platform_device_msi_init_and_alloc_irqs(dev, mbox->msi_count,
+							     mpxy_mbox_msi_write);
+		if (rc) {
+			return dev_err_probe(dev, rc, "Failed to allocate %d MSIs\n",
+					     mbox->msi_count);
+		}
+
+		for (i = 0; i < mbox->channel_count; i++) {
+			mchan = &mbox->channels[i];
+			if (mchan->msi_index == U32_MAX)
+				continue;
+			mchan->msi_irq = msi_get_virq(dev, mchan->msi_index);
+		}
+	}
+
+	/* Register mailbox controller */
+	rc = devm_mbox_controller_register(dev, &mbox->controller);
+	if (rc) {
+		dev_err_probe(dev, rc, "Registering SBI MPXY mailbox failed\n");
+		if (mbox->msi_count)
+			platform_device_msi_free_irqs_all(dev);
+		return rc;
+	}
+
+	dev_info(dev, "mailbox registered with %d channels\n",
+		 mbox->channel_count);
+	return 0;
+}
+
+static void mpxy_mbox_remove(struct platform_device *pdev)
+{
+	struct mpxy_mbox *mbox = platform_get_drvdata(pdev);
+
+	if (mbox->msi_count)
+		platform_device_msi_free_irqs_all(mbox->dev);
+}
+
+static const struct of_device_id mpxy_mbox_of_match[] = {
+	{ .compatible = "riscv,sbi-mpxy-mbox" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mpxy_mbox_of_match);
+
+static struct platform_driver mpxy_mbox_driver = {
+	.driver = {
+		.name = "riscv-sbi-mpxy-mbox",
+		.of_match_table = mpxy_mbox_of_match,
+	},
+	.probe = mpxy_mbox_probe,
+	.remove = mpxy_mbox_remove,
+};
+module_platform_driver(mpxy_mbox_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Anup Patel <apatel@ventanamicro.com>");
+MODULE_DESCRIPTION("RISC-V SBI MPXY mailbox controller driver");
-- 
2.43.0

[PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Anup Patel]

Add device tree bindings for the RPMI clock service group based
message proxy implemented by the SBI implementation (machine mode
firmware or hypervisor).

The RPMI clock service group is defined by the RISC-V platform
management interface (RPMI) specification.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../bindings/clock/riscv,rpmi-mpxy-clock.yaml | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml

diff --git a/Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml b/Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
new file mode 100644
index 000000000000..70ffc88d0110
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/riscv,rpmi-mpxy-clock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V RPMI clock service group based message proxy
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a
+  messaging protocol which is modular and extensible. The supervisor
+  software can send/receive RPMI messages via SBI MPXY extension [2]
+  or some dedicated supervisor-mode RPMI transport.
+
+  The RPMI specification [1] defines clock service group for accessing
+  system clocks managed by a platform microcontroller. The SBI implementation
+  (machine mode firmware or hypervisor) can implement an SBI MPXY channel
+  to allow RPMI clock service group access to the supervisor software.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+  [2] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+properties:
+  compatible:
+    description:
+      Intended for use by the SBI implementation.
+    const: riscv,rpmi-mpxy-clock
+
+  mboxes:
+    maxItems: 1
+    description:
+      Mailbox channel of the underlying RPMI transport.
+
+  riscv,sbi-mpxy-channel-id:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      The SBI MPXY channel id to be used for providing RPMI access to
+      the supervisor software.
+
+required:
+  - compatible
+  - mboxes
+  - riscv,sbi-mpxy-channel-id
+
+additionalProperties: false
+
+examples:
+  - |
+    clock-controller {
+        compatible = "riscv,rpmi-mpxy-clock";
+        mboxes = <&rpmi_shmem_mbox 0x8>;
+        riscv,sbi-mpxy-channel-id = <0x1000>;
+    };
+...
-- 
2.43.0

[PATCH v8 09/24] dt-bindings: clock: Add RPMI clock service controller bindings

[Anup Patel]

Add device tree bindings for the RPMI clock service group based
controller for the supervisor software.

The RPMI clock service group is defined by the RISC-V platform
management interface (RPMI) specification.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../bindings/clock/riscv,rpmi-clock.yaml      | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml

diff --git a/Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml b/Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
new file mode 100644
index 000000000000..5d62bf8215c8
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/riscv,rpmi-clock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V RPMI clock service group based clock controller
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a
+  messaging protocol which is modular and extensible. The supervisor
+  software can send/receive RPMI messages via SBI MPXY extension [2]
+  or some dedicated supervisor-mode RPMI transport.
+
+  The RPMI specification [1] defines clock service group for accessing
+  system clocks managed by a platform microcontroller. The supervisor
+  software can access RPMI clock service group via SBI MPXY channel or
+  some dedicated supervisor-mode RPMI transport.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+  [2] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+properties:
+  compatible:
+    description:
+      Intended for use by the supervisor software.
+    const: riscv,rpmi-clock
+
+  mboxes:
+    maxItems: 1
+    description:
+      Mailbox channel of the underlying RPMI transport or SBI message proxy channel.
+
+  "#clock-cells":
+    const: 1
+    description:
+      Platform specific CLOCK_ID as defined by the RISC-V Platform Management
+      Interface (RPMI) specification.
+
+required:
+  - compatible
+  - mboxes
+  - "#clock-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    clock-controller {
+        compatible = "riscv,rpmi-clock";
+        mboxes = <&mpxy_mbox 0x1000 0x0>;
+        #clock-cells = <1>;
+    };
+...
-- 
2.43.0

[PATCH v8 10/24] clk: Add clock driver for the RISC-V RPMI clock service group

[Anup Patel]

From: Rahul Pathak <rpathak@ventanamicro.com>

The RPMI specification defines a clock service group which can be
accessed via SBI MPXY extension or dedicated S-mode RPMI transport.

Add mailbox client based clock driver for the RISC-V RPMI clock
service group.

Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Co-developed-by: Anup Patel <apatel@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
---
 drivers/clk/Kconfig                        |   8 +
 drivers/clk/Makefile                       |   1 +
 drivers/clk/clk-rpmi.c                     | 616 +++++++++++++++++++++
 include/linux/mailbox/riscv-rpmi-message.h |  16 +
 include/linux/wordpart.h                   |   8 +
 5 files changed, 649 insertions(+)
 create mode 100644 drivers/clk/clk-rpmi.c

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 19c1ed280fd7..2e385b146f8b 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -493,6 +493,14 @@ config COMMON_CLK_SP7021
 	  Not all features of the PLL are currently supported
 	  by the driver.
 
+config COMMON_CLK_RPMI
+	tristate "Clock driver based on RISC-V RPMI"
+	depends on MAILBOX
+	default RISCV
+	help
+	  Support for clocks based on the clock service group defined by
+	  the RISC-V platform management interface (RPMI) specification.
+
 source "drivers/clk/actions/Kconfig"
 source "drivers/clk/analogbits/Kconfig"
 source "drivers/clk/baikal-t1/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 42867cd37c33..48866e429a40 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -84,6 +84,7 @@ obj-$(CONFIG_CLK_LS1028A_PLLDIG)	+= clk-plldig.o
 obj-$(CONFIG_COMMON_CLK_PWM)		+= clk-pwm.o
 obj-$(CONFIG_CLK_QORIQ)			+= clk-qoriq.o
 obj-$(CONFIG_COMMON_CLK_RK808)		+= clk-rk808.o
+obj-$(CONFIG_COMMON_CLK_RPMI)		+= clk-rpmi.o
 obj-$(CONFIG_COMMON_CLK_HI655X)		+= clk-hi655x.o
 obj-$(CONFIG_COMMON_CLK_S2MPS11)	+= clk-s2mps11.o
 obj-$(CONFIG_COMMON_CLK_SCMI)           += clk-scmi.o
diff --git a/drivers/clk/clk-rpmi.c b/drivers/clk/clk-rpmi.c
new file mode 100644
index 000000000000..e0a371586695
--- /dev/null
+++ b/drivers/clk/clk-rpmi.c
@@ -0,0 +1,616 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RISC-V MPXY Based Clock Driver
+ *
+ * Copyright (C) 2025 Ventana Micro Systems Ltd.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox/riscv-rpmi-message.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/wordpart.h>
+
+#define RPMI_CLK_DISCRETE_MAX_NUM_RATES		16
+#define RPMI_CLK_NAME_LEN			16
+
+#define to_rpmi_clk(clk)	container_of(clk, struct rpmi_clk, hw)
+
+#define rpmi_clkrate_u64(hi, lo)	make_u64_from_two_u32(hi, lo)
+
+enum rpmi_clk_config {
+	RPMI_CLK_DISABLE = 0,
+	RPMI_CLK_ENABLE = 1,
+	RPMI_CLK_CONFIG_MAX_IDX
+};
+
+enum rpmi_clk_type {
+	RPMI_CLK_DISCRETE = 0,
+	RPMI_CLK_LINEAR = 1,
+	RPMI_CLK_TYPE_MAX_IDX
+};
+
+struct rpmi_clk_context {
+	struct device *dev;
+	struct mbox_chan *chan;
+	struct mbox_client client;
+	u32 max_msg_data_size;
+};
+
+/*
+ * rpmi_clk_rates represents the rates format
+ * as specified by the RPMI specification.
+ * No other data format (e.g., struct linear_range)
+ * is required to avoid to and from conversion.
+ */
+union rpmi_clk_rates {
+	u64 discrete[RPMI_CLK_DISCRETE_MAX_NUM_RATES];
+	struct {
+		u64 min;
+		u64 max;
+		u64 step;
+	} linear;
+};
+
+struct rpmi_clk {
+	struct rpmi_clk_context *context;
+	u32 id;
+	u32 num_rates;
+	u32 transition_latency;
+	enum rpmi_clk_type type;
+	union rpmi_clk_rates *rates;
+	char name[RPMI_CLK_NAME_LEN];
+	struct clk_hw hw;
+};
+
+struct rpmi_clk_rate_discrete {
+	__le32 lo;
+	__le32 hi;
+};
+
+struct rpmi_clk_rate_linear {
+	__le32 min_lo;
+	__le32 min_hi;
+	__le32 max_lo;
+	__le32 max_hi;
+	__le32 step_lo;
+	__le32 step_hi;
+};
+
+struct rpmi_get_num_clocks_rx {
+	__le32 status;
+	__le32 num_clocks;
+};
+
+struct rpmi_get_attrs_tx {
+	__le32 clkid;
+};
+
+struct rpmi_get_attrs_rx {
+	__le32 status;
+	__le32 flags;
+	__le32 num_rates;
+	__le32 transition_latency;
+	char name[RPMI_CLK_NAME_LEN];
+};
+
+struct rpmi_get_supp_rates_tx {
+	__le32 clkid;
+	__le32 clk_rate_idx;
+};
+
+struct rpmi_get_supp_rates_rx {
+	__le32 status;
+	__le32 flags;
+	__le32 remaining;
+	__le32 returned;
+	__le32 rates[];
+};
+
+struct rpmi_get_rate_tx {
+	__le32 clkid;
+};
+
+struct rpmi_get_rate_rx {
+	__le32 status;
+	__le32 lo;
+	__le32 hi;
+};
+
+struct rpmi_set_rate_tx {
+	__le32 clkid;
+	__le32 flags;
+	__le32 lo;
+	__le32 hi;
+};
+
+struct rpmi_set_rate_rx {
+	__le32 status;
+};
+
+struct rpmi_set_config_tx {
+	__le32 clkid;
+	__le32 config;
+};
+
+struct rpmi_set_config_rx {
+	__le32 status;
+};
+
+static u32 rpmi_clk_get_num_clocks(struct rpmi_clk_context *context)
+{
+	struct rpmi_get_num_clocks_rx rx, *resp;
+	struct rpmi_mbox_message msg;
+	int ret;
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_GET_NUM_CLOCKS,
+					  NULL, 0, &rx, sizeof(rx));
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return 0;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp || resp->status)
+		return 0;
+
+	return le32_to_cpu(resp->num_clocks);
+}
+
+static int rpmi_clk_get_attrs(u32 clkid, struct rpmi_clk *rpmi_clk)
+{
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_mbox_message msg;
+	struct rpmi_get_attrs_tx tx;
+	struct rpmi_get_attrs_rx rx, *resp;
+	u8 format;
+	int ret;
+
+	tx.clkid = cpu_to_le32(clkid);
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_GET_ATTRIBUTES,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return ret;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp)
+		return -EINVAL;
+	if (resp->status)
+		return rpmi_to_linux_error(le32_to_cpu(resp->status));
+
+	rpmi_clk->id = clkid;
+	rpmi_clk->num_rates = le32_to_cpu(resp->num_rates);
+	rpmi_clk->transition_latency = le32_to_cpu(resp->transition_latency);
+	strscpy(rpmi_clk->name, resp->name, RPMI_CLK_NAME_LEN);
+
+	format = le32_to_cpu(resp->flags) & 3U;
+	if (format >= RPMI_CLK_TYPE_MAX_IDX)
+		return -EINVAL;
+
+	rpmi_clk->type = format;
+
+	return 0;
+}
+
+static int rpmi_clk_get_supported_rates(u32 clkid, struct rpmi_clk *rpmi_clk)
+{
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_clk_rate_discrete *rate_discrete;
+	struct rpmi_clk_rate_linear *rate_linear;
+	struct rpmi_get_supp_rates_tx tx;
+	struct rpmi_get_supp_rates_rx *resp;
+	struct rpmi_mbox_message msg;
+	size_t clk_rate_idx;
+	int ret, rateidx, j;
+
+	tx.clkid = cpu_to_le32(clkid);
+	tx.clk_rate_idx = 0;
+
+	/*
+	 * Make sure we allocate rx buffer sufficient to be accommodate all
+	 * the rates sent in one RPMI message.
+	 */
+	struct rpmi_get_supp_rates_rx *rx __free(kfree) =
+					kzalloc(context->max_msg_data_size, GFP_KERNEL);
+	if (!rx)
+		return -ENOMEM;
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_GET_SUPPORTED_RATES,
+					  &tx, sizeof(tx), rx, context->max_msg_data_size);
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return ret;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp)
+		return -EINVAL;
+	if (resp->status)
+		return rpmi_to_linux_error(le32_to_cpu(resp->status));
+	if (!le32_to_cpu(resp->returned))
+		return -EINVAL;
+
+	if (rpmi_clk->type == RPMI_CLK_DISCRETE) {
+		rate_discrete = (struct rpmi_clk_rate_discrete *)resp->rates;
+
+		for (rateidx = 0; rateidx < le32_to_cpu(resp->returned); rateidx++) {
+			rpmi_clk->rates->discrete[rateidx] =
+				rpmi_clkrate_u64(le32_to_cpu(rate_discrete[rateidx].hi),
+						 le32_to_cpu(rate_discrete[rateidx].lo));
+		}
+
+		/*
+		 * Keep sending the request message until all
+		 * the rates are received.
+		 */
+		clk_rate_idx = 0;
+		while (le32_to_cpu(resp->remaining)) {
+			clk_rate_idx += le32_to_cpu(resp->returned);
+			tx.clk_rate_idx = cpu_to_le32(clk_rate_idx);
+
+			rpmi_mbox_init_send_with_response(&msg,
+							  RPMI_CLK_SRV_GET_SUPPORTED_RATES,
+							  &tx, sizeof(tx),
+							  rx, context->max_msg_data_size);
+
+			ret = rpmi_mbox_send_message(context->chan, &msg);
+			if (ret)
+				return ret;
+
+			resp = rpmi_mbox_get_msg_response(&msg);
+			if (!resp)
+				return -EINVAL;
+			if (resp->status)
+				return rpmi_to_linux_error(le32_to_cpu(resp->status));
+			if (!le32_to_cpu(resp->returned))
+				return -EINVAL;
+
+			for (j = 0; j < le32_to_cpu(resp->returned); j++) {
+				if (rateidx >= clk_rate_idx + le32_to_cpu(resp->returned))
+					break;
+				rpmi_clk->rates->discrete[rateidx++] =
+					rpmi_clkrate_u64(le32_to_cpu(rate_discrete[j].hi),
+							 le32_to_cpu(rate_discrete[j].lo));
+			}
+		}
+	} else if (rpmi_clk->type == RPMI_CLK_LINEAR) {
+		rate_linear = (struct rpmi_clk_rate_linear *)resp->rates;
+
+		rpmi_clk->rates->linear.min = rpmi_clkrate_u64(le32_to_cpu(rate_linear->min_hi),
+							       le32_to_cpu(rate_linear->min_lo));
+		rpmi_clk->rates->linear.max = rpmi_clkrate_u64(le32_to_cpu(rate_linear->max_hi),
+							       le32_to_cpu(rate_linear->max_lo));
+		rpmi_clk->rates->linear.step = rpmi_clkrate_u64(le32_to_cpu(rate_linear->step_hi),
+								le32_to_cpu(rate_linear->step_lo));
+	}
+
+	return 0;
+}
+
+static unsigned long rpmi_clk_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	struct rpmi_clk *rpmi_clk = to_rpmi_clk(hw);
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_mbox_message msg;
+	struct rpmi_get_rate_tx tx;
+	struct rpmi_get_rate_rx rx, *resp;
+	int ret;
+
+	tx.clkid = cpu_to_le32(rpmi_clk->id);
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_GET_RATE,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return ret;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp)
+		return -EINVAL;
+	if (resp->status)
+		return rpmi_to_linux_error(le32_to_cpu(resp->status));
+
+	return rpmi_clkrate_u64(le32_to_cpu(resp->hi), le32_to_cpu(resp->lo));
+}
+
+static int rpmi_clk_determine_rate(struct clk_hw *hw,
+				   struct clk_rate_request *req)
+{
+	struct rpmi_clk *rpmi_clk = to_rpmi_clk(hw);
+	u64 fmin, fmax, ftmp;
+
+	/*
+	 * Keep the requested rate if the clock format
+	 * is of discrete type. Let the platform which
+	 * is actually controlling the clock handle that.
+	 */
+	if (rpmi_clk->type == RPMI_CLK_DISCRETE)
+		return 0;
+
+	fmin = rpmi_clk->rates->linear.min;
+	fmax = rpmi_clk->rates->linear.max;
+
+	if (req->rate <= fmin) {
+		req->rate = fmin;
+		return 0;
+	} else if (req->rate >= fmax) {
+		req->rate = fmax;
+		return 0;
+	}
+
+	ftmp = req->rate - fmin;
+	ftmp += rpmi_clk->rates->linear.step - 1;
+	do_div(ftmp, rpmi_clk->rates->linear.step);
+
+	req->rate = ftmp * rpmi_clk->rates->linear.step + fmin;
+
+	return 0;
+}
+
+static int rpmi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+			     unsigned long parent_rate)
+{
+	struct rpmi_clk *rpmi_clk = to_rpmi_clk(hw);
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_mbox_message msg;
+	struct rpmi_set_rate_tx tx;
+	struct rpmi_set_rate_rx rx, *resp;
+	int ret;
+
+	tx.clkid = cpu_to_le32(rpmi_clk->id);
+	tx.lo = cpu_to_le32(lower_32_bits(rate));
+	tx.hi = cpu_to_le32(upper_32_bits(rate));
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_SET_RATE,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return ret;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp)
+		return -EINVAL;
+	if (resp->status)
+		return rpmi_to_linux_error(le32_to_cpu(resp->status));
+
+	return 0;
+}
+
+static int rpmi_clk_enable(struct clk_hw *hw)
+{
+	struct rpmi_clk *rpmi_clk = to_rpmi_clk(hw);
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_mbox_message msg;
+	struct rpmi_set_config_tx tx;
+	struct rpmi_set_config_rx rx, *resp;
+	int ret;
+
+	tx.config = cpu_to_le32(RPMI_CLK_ENABLE);
+	tx.clkid = cpu_to_le32(rpmi_clk->id);
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_SET_CONFIG,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return ret;
+
+	resp = rpmi_mbox_get_msg_response(&msg);
+	if (!resp)
+		return -EINVAL;
+	if (resp->status)
+		return rpmi_to_linux_error(le32_to_cpu(resp->status));
+
+	return 0;
+}
+
+static void rpmi_clk_disable(struct clk_hw *hw)
+{
+	struct rpmi_clk *rpmi_clk = to_rpmi_clk(hw);
+	struct rpmi_clk_context *context = rpmi_clk->context;
+	struct rpmi_mbox_message msg;
+	struct rpmi_set_config_tx tx;
+	struct rpmi_set_config_rx rx;
+
+	tx.config = cpu_to_le32(RPMI_CLK_DISABLE);
+	tx.clkid = cpu_to_le32(rpmi_clk->id);
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_CLK_SRV_SET_CONFIG,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+
+	rpmi_mbox_send_message(context->chan, &msg);
+}
+
+static const struct clk_ops rpmi_clk_ops = {
+	.recalc_rate = rpmi_clk_recalc_rate,
+	.determine_rate = rpmi_clk_determine_rate,
+	.set_rate = rpmi_clk_set_rate,
+	.prepare = rpmi_clk_enable,
+	.unprepare = rpmi_clk_disable,
+};
+
+static struct clk_hw *rpmi_clk_enumerate(struct rpmi_clk_context *context, u32 clkid)
+{
+	struct device *dev = context->dev;
+	unsigned long min_rate, max_rate;
+	union rpmi_clk_rates *rates;
+	struct rpmi_clk *rpmi_clk;
+	struct clk_init_data init = {};
+	struct clk_hw *clk_hw;
+	int ret;
+
+	rates = devm_kzalloc(dev, sizeof(*rates), GFP_KERNEL);
+	if (!rates)
+		return ERR_PTR(-ENOMEM);
+
+	rpmi_clk = devm_kzalloc(dev, sizeof(*rpmi_clk), GFP_KERNEL);
+	if (!rpmi_clk)
+		return ERR_PTR(-ENOMEM);
+
+	rpmi_clk->context = context;
+	rpmi_clk->rates = rates;
+
+	ret = rpmi_clk_get_attrs(clkid, rpmi_clk);
+	if (ret)
+		return dev_err_ptr_probe(dev, ret,
+					 "Failed to get clk-%u attributes\n",
+					 clkid);
+
+	ret = rpmi_clk_get_supported_rates(clkid, rpmi_clk);
+	if (ret)
+		return dev_err_ptr_probe(dev, ret,
+					 "Get supported rates failed for clk-%u\n",
+					 clkid);
+
+	init.flags = CLK_GET_RATE_NOCACHE;
+	init.num_parents = 0;
+	init.ops = &rpmi_clk_ops;
+	init.name = rpmi_clk->name;
+	clk_hw = &rpmi_clk->hw;
+	clk_hw->init = &init;
+
+	ret = devm_clk_hw_register(dev, clk_hw);
+	if (ret)
+		return dev_err_ptr_probe(dev, ret,
+					 "Unable to register clk-%u\n",
+					 clkid);
+
+	if (rpmi_clk->type == RPMI_CLK_DISCRETE) {
+		min_rate = rpmi_clk->rates->discrete[0];
+		max_rate = rpmi_clk->rates->discrete[rpmi_clk->num_rates -  1];
+	} else {
+		min_rate = rpmi_clk->rates->linear.min;
+		max_rate = rpmi_clk->rates->linear.max;
+	}
+
+	clk_hw_set_rate_range(clk_hw, min_rate, max_rate);
+
+	return clk_hw;
+}
+
+static void rpmi_clk_mbox_chan_release(void *data)
+{
+	struct mbox_chan *chan = data;
+
+	mbox_free_channel(chan);
+}
+
+static int rpmi_clk_probe(struct platform_device *pdev)
+{
+	int ret;
+	unsigned int num_clocks, i;
+	struct clk_hw_onecell_data *clk_data;
+	struct rpmi_clk_context *context;
+	struct rpmi_mbox_message msg;
+	struct clk_hw *hw_ptr;
+	struct device *dev = &pdev->dev;
+
+	context = devm_kzalloc(dev, sizeof(*context), GFP_KERNEL);
+	if (!context)
+		return -ENOMEM;
+	context->dev = dev;
+	platform_set_drvdata(pdev, context);
+
+	context->client.dev		= context->dev;
+	context->client.rx_callback	= NULL;
+	context->client.tx_block	= false;
+	context->client.knows_txdone	= true;
+	context->client.tx_tout		= 0;
+
+	context->chan = mbox_request_channel(&context->client, 0);
+	if (IS_ERR(context->chan))
+		return PTR_ERR(context->chan);
+
+	ret = devm_add_action_or_reset(dev, rpmi_clk_mbox_chan_release, context->chan);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to add rpmi mbox channel cleanup\n");
+
+	rpmi_mbox_init_get_attribute(&msg, RPMI_MBOX_ATTR_SPEC_VERSION);
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get spec version\n");
+	if (msg.attr.value < RPMI_MKVER(1, 0)) {
+		return dev_err_probe(dev, -EINVAL,
+				     "msg protocol version mismatch, expected 0x%x, found 0x%x\n",
+				     RPMI_MKVER(1, 0), msg.attr.value);
+	}
+
+	rpmi_mbox_init_get_attribute(&msg, RPMI_MBOX_ATTR_SERVICEGROUP_ID);
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get service group ID\n");
+	if (msg.attr.value != RPMI_SRVGRP_CLOCK) {
+		return dev_err_probe(dev, -EINVAL,
+				     "service group match failed, expected 0x%x, found 0x%x\n",
+				     RPMI_SRVGRP_CLOCK, msg.attr.value);
+	}
+
+	rpmi_mbox_init_get_attribute(&msg, RPMI_MBOX_ATTR_SERVICEGROUP_VERSION);
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get service group version\n");
+	if (msg.attr.value < RPMI_MKVER(1, 0)) {
+		return dev_err_probe(dev, -EINVAL,
+				     "service group version failed, expected 0x%x, found 0x%x\n",
+				     RPMI_MKVER(1, 0), msg.attr.value);
+	}
+
+	rpmi_mbox_init_get_attribute(&msg, RPMI_MBOX_ATTR_MAX_MSG_DATA_SIZE);
+	ret = rpmi_mbox_send_message(context->chan, &msg);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get max message data size\n");
+
+	context->max_msg_data_size = msg.attr.value;
+	num_clocks = rpmi_clk_get_num_clocks(context);
+	if (!num_clocks)
+		return dev_err_probe(dev, -ENODEV, "No clocks found\n");
+
+	clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, num_clocks),
+				GFP_KERNEL);
+	if (!clk_data)
+		return dev_err_probe(dev, -ENOMEM, "No memory for clock data\n");
+	clk_data->num = num_clocks;
+
+	for (i = 0; i < clk_data->num; i++) {
+		hw_ptr = rpmi_clk_enumerate(context, i);
+		if (IS_ERR(hw_ptr)) {
+			return dev_err_probe(dev, PTR_ERR(hw_ptr),
+					     "Failed to register clk-%d\n", i);
+		}
+		clk_data->hws[i] = hw_ptr;
+	}
+
+	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clk_data);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to register clock HW provider\n");
+
+	return 0;
+}
+
+static const struct of_device_id rpmi_clk_of_match[] = {
+	{ .compatible = "riscv,rpmi-clock" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rpmi_clk_of_match);
+
+static struct platform_driver rpmi_clk_driver = {
+	.driver = {
+		.name = "riscv-rpmi-clock",
+		.of_match_table = rpmi_clk_of_match,
+	},
+	.probe = rpmi_clk_probe,
+};
+module_platform_driver(rpmi_clk_driver);
+
+MODULE_AUTHOR("Rahul Pathak <rpathak@ventanamicro.com>");
+MODULE_DESCRIPTION("Clock Driver based on RPMI message protocol");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mailbox/riscv-rpmi-message.h b/include/linux/mailbox/riscv-rpmi-message.h
index 3f4c73529aa5..c90918dca367 100644
--- a/include/linux/mailbox/riscv-rpmi-message.h
+++ b/include/linux/mailbox/riscv-rpmi-message.h
@@ -90,6 +90,22 @@ static inline int rpmi_to_linux_error(int rpmi_error)
 	}
 }
 
+/* RPMI service group IDs */
+#define RPMI_SRVGRP_CLOCK		0x00008
+
+/* RPMI clock service IDs */
+enum rpmi_clock_service_id {
+	RPMI_CLK_SRV_ENABLE_NOTIFICATION = 0x01,
+	RPMI_CLK_SRV_GET_NUM_CLOCKS = 0x02,
+	RPMI_CLK_SRV_GET_ATTRIBUTES = 0x03,
+	RPMI_CLK_SRV_GET_SUPPORTED_RATES = 0x04,
+	RPMI_CLK_SRV_SET_CONFIG = 0x05,
+	RPMI_CLK_SRV_GET_CONFIG = 0x06,
+	RPMI_CLK_SRV_SET_RATE = 0x07,
+	RPMI_CLK_SRV_GET_RATE = 0x08,
+	RPMI_CLK_SRV_ID_MAX_COUNT
+};
+
 /* RPMI Linux mailbox attribute IDs */
 enum rpmi_mbox_attribute_id {
 	RPMI_MBOX_ATTR_SPEC_VERSION,
diff --git a/include/linux/wordpart.h b/include/linux/wordpart.h
index ed8717730037..5cad9c244bf2 100644
--- a/include/linux/wordpart.h
+++ b/include/linux/wordpart.h
@@ -39,6 +39,14 @@
  */
 #define make_u32_from_two_u16(hi, lo)	(((u32)(hi) << 16) | (u32)(lo))
 
+/**
+ * make_u64_from_two_u32 - return u64 number by combining
+ * two u32 numbers.
+ * @hi: upper 32 bit number
+ * @lo: lower 32 bit number
+ */
+#define make_u64_from_two_u32(hi, lo)	(((u64)(hi) << 32) | (u32)(lo))
+
 /**
  * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value
  * @x: value to repeat
-- 
2.43.0

[PATCH v8 11/24] dt-bindings: Add RPMI system MSI message proxy bindings

[Anup Patel]

Add device tree bindings for the RPMI system MSI service group
based message proxy implemented by the SBI implementation (machine
mode firmware or hypervisor).

The RPMI system MSI service group is defined by the RISC-V
platform management interface (RPMI) specification.

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../riscv,rpmi-mpxy-system-msi.yaml           | 67 +++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml

diff --git a/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml b/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
new file mode 100644
index 000000000000..1991f5c7446a
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V RPMI system MSI service group based message proxy
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a
+  messaging protocol which is modular and extensible. The supervisor
+  software can send/receive RPMI messages via SBI MPXY extension [2]
+  or some dedicated supervisor-mode RPMI transport.
+
+  The RPMI specification [1] defines system MSI service group which
+  allow application processors to receive MSIs upon system events
+  such as P2A doorbell, graceful shutdown/reboot request, CPU hotplug
+  event, memory hotplug event, etc from the platform microcontroller.
+  The SBI implementation (machine mode firmware or hypervisor) can
+  implement an SBI MPXY channel to allow RPMI system MSI service
+  group access to the supervisor software.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+  [2] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+properties:
+  compatible:
+    description:
+      Intended for use by the SBI implementation.
+    const: riscv,rpmi-mpxy-system-msi
+
+  mboxes:
+    maxItems: 1
+    description:
+      Mailbox channel of the underlying RPMI transport.
+
+  riscv,sbi-mpxy-channel-id:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      The SBI MPXY channel id to be used for providing RPMI access to
+      the supervisor software.
+
+required:
+  - compatible
+  - mboxes
+  - riscv,sbi-mpxy-channel-id
+
+additionalProperties: false
+
+examples:
+  - |
+    interrupt-controller {
+        compatible = "riscv,rpmi-mpxy-system-msi";
+        mboxes = <&rpmi_shmem_mbox 0x2>;
+        riscv,sbi-mpxy-channel-id = <0x2000>;
+    };
+...
-- 
2.43.0

[PATCH v8 12/24] dt-bindings: Add RPMI system MSI interrupt controller bindings

[Anup Patel]

Add device tree bindings for the RPMI system MSI service group
based interrupt controller for the supervisor software.

The RPMI system MSI service group is defined by the RISC-V
platform management interface (RPMI) specification.

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../riscv,rpmi-system-msi.yaml                | 74 +++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml

diff --git a/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml b/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
new file mode 100644
index 000000000000..b10a0532e586
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/riscv,rpmi-system-msi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V RPMI system MSI service group based interrupt controller
+
+maintainers:
+  - Anup Patel <anup@brainfault.org>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a
+  messaging protocol which is modular and extensible. The supervisor
+  software can send/receive RPMI messages via SBI MPXY extension [2]
+  or some dedicated supervisor-mode RPMI transport.
+
+  The RPMI specification [1] defines system MSI service group which
+  allow application processors to receive MSIs upon system events
+  such as P2A doorbell, graceful shutdown/reboot request, CPU hotplug
+  event, memory hotplug event, etc from the platform microcontroller.
+  The supervisor software can access RPMI system MSI service group via
+  SBI MPXY channel or some dedicated supervisor-mode RPMI transport.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+  [2] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+allOf:
+  - $ref: /schemas/interrupt-controller.yaml#
+
+properties:
+  compatible:
+    description:
+      Intended for use by the supervisor software.
+    const: riscv,rpmi-system-msi
+
+  mboxes:
+    maxItems: 1
+    description:
+      Mailbox channel of the underlying RPMI transport or SBI message proxy channel.
+
+  msi-parent: true
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 1
+
+required:
+  - compatible
+  - mboxes
+  - msi-parent
+  - interrupt-controller
+  - "#interrupt-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    interrupt-controller {
+        compatible = "riscv,rpmi-system-msi";
+        mboxes = <&mpxy_mbox 0x2000 0x0>;
+        msi-parent = <&imsic_slevel>;
+        interrupt-controller;
+        #interrupt-cells = <1>;
+    };
+...
-- 
2.43.0

[PATCH v8 13/24] irqchip: Add driver for the RPMI system MSI service group

[Anup Patel]

The RPMI specification defines a system MSI service group which
allows application processors to receive MSIs upon system events
such as graceful shutdown/reboot request, CPU hotplug event, memory
hotplug event, etc.

Add an irqchip driver for the RISC-V RPMI system MSI service group
to directly receive system MSIs in Linux kernel.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/irqchip/Kconfig                    |   7 +
 drivers/irqchip/Makefile                   |   1 +
 drivers/irqchip/irq-riscv-rpmi-sysmsi.c    | 287 +++++++++++++++++++++
 include/linux/mailbox/riscv-rpmi-message.h |  13 +
 4 files changed, 308 insertions(+)
 create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 0d196e447142..96bf6aa55681 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -617,6 +617,13 @@ config RISCV_IMSIC
 	select GENERIC_MSI_IRQ
 	select IRQ_MSI_LIB
 
+config RISCV_RPMI_SYSMSI
+	bool
+	depends on MAILBOX
+	select IRQ_DOMAIN_HIERARCHY
+	select GENERIC_MSI_IRQ
+	default RISCV
+
 config SIFIVE_PLIC
 	bool
 	depends on RISCV
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 23ca4959e6ce..4fd966aa78ab 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -103,6 +103,7 @@ obj-$(CONFIG_RISCV_INTC)		+= irq-riscv-intc.o
 obj-$(CONFIG_RISCV_APLIC)		+= irq-riscv-aplic-main.o irq-riscv-aplic-direct.o
 obj-$(CONFIG_RISCV_APLIC_MSI)		+= irq-riscv-aplic-msi.o
 obj-$(CONFIG_RISCV_IMSIC)		+= irq-riscv-imsic-state.o irq-riscv-imsic-early.o irq-riscv-imsic-platform.o
+obj-$(CONFIG_RISCV_RPMI_SYSMSI)		+= irq-riscv-rpmi-sysmsi.o
 obj-$(CONFIG_SIFIVE_PLIC)		+= irq-sifive-plic.o
 obj-$(CONFIG_STARFIVE_JH8100_INTC)	+= irq-starfive-jh8100-intc.o
 obj-$(CONFIG_THEAD_C900_ACLINT_SSWI)	+= irq-thead-c900-aclint-sswi.o
diff --git a/drivers/irqchip/irq-riscv-rpmi-sysmsi.c b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
new file mode 100644
index 000000000000..92e8847dfccc
--- /dev/null
+++ b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2025 Ventana Micro Systems Inc. */
+
+#include <linux/bits.h>
+#include <linux/bug.h>
+#include <linux/device.h>
+#include <linux/device/devres.h>
+#include <linux/dev_printk.h>
+#include <linux/errno.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox/riscv-rpmi-message.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+struct rpmi_sysmsi_get_attrs_rx {
+	__le32 status;
+	__le32 sys_num_msi;
+	__le32 flag0;
+	__le32 flag1;
+};
+
+#define RPMI_SYSMSI_MSI_ATTRIBUTES_FLAG0_PREF_PRIV	BIT(0)
+
+struct rpmi_sysmsi_set_msi_state_tx {
+	__le32 sys_msi_index;
+	__le32 sys_msi_state;
+};
+
+struct rpmi_sysmsi_set_msi_state_rx {
+	__le32 status;
+};
+
+#define RPMI_SYSMSI_MSI_STATE_ENABLE			BIT(0)
+#define RPMI_SYSMSI_MSI_STATE_PENDING			BIT(1)
+
+struct rpmi_sysmsi_set_msi_target_tx {
+	__le32 sys_msi_index;
+	__le32 sys_msi_address_low;
+	__le32 sys_msi_address_high;
+	__le32 sys_msi_data;
+};
+
+struct rpmi_sysmsi_set_msi_target_rx {
+	__le32 status;
+};
+
+struct rpmi_sysmsi_priv {
+	struct device		*dev;
+	struct mbox_client	client;
+	struct mbox_chan	*chan;
+	u32			nr_irqs;
+	u32			gsi_base;
+};
+
+static int rpmi_sysmsi_get_num_msi(struct rpmi_sysmsi_priv *priv)
+{
+	struct rpmi_sysmsi_get_attrs_rx rx;
+	struct rpmi_mbox_message msg;
+	int ret;
+
+	rpmi_mbox_init_send_with_response(&msg, RPMI_SYSMSI_SRV_GET_ATTRIBUTES,
+					  NULL, 0, &rx, sizeof(rx));
+	ret = rpmi_mbox_send_message(priv->chan, &msg);
+	if (ret)
+		return ret;
+	if (rx.status)
+		return rpmi_to_linux_error(le32_to_cpu(rx.status));
+
+	return le32_to_cpu(rx.sys_num_msi);
+}
+
+static int rpmi_sysmsi_set_msi_state(struct rpmi_sysmsi_priv *priv,
+				     u32 sys_msi_index, u32 sys_msi_state)
+{
+	struct rpmi_sysmsi_set_msi_state_tx tx;
+	struct rpmi_sysmsi_set_msi_state_rx rx;
+	struct rpmi_mbox_message msg;
+	int ret;
+
+	tx.sys_msi_index = cpu_to_le32(sys_msi_index);
+	tx.sys_msi_state = cpu_to_le32(sys_msi_state);
+	rpmi_mbox_init_send_with_response(&msg, RPMI_SYSMSI_SRV_SET_MSI_STATE,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+	ret = rpmi_mbox_send_message(priv->chan, &msg);
+	if (ret)
+		return ret;
+	if (rx.status)
+		return rpmi_to_linux_error(le32_to_cpu(rx.status));
+
+	return 0;
+}
+
+static int rpmi_sysmsi_set_msi_target(struct rpmi_sysmsi_priv *priv,
+				      u32 sys_msi_index, struct msi_msg *m)
+{
+	struct rpmi_sysmsi_set_msi_target_tx tx;
+	struct rpmi_sysmsi_set_msi_target_rx rx;
+	struct rpmi_mbox_message msg;
+	int ret;
+
+	tx.sys_msi_index = cpu_to_le32(sys_msi_index);
+	tx.sys_msi_address_low = cpu_to_le32(m->address_lo);
+	tx.sys_msi_address_high = cpu_to_le32(m->address_hi);
+	tx.sys_msi_data = cpu_to_le32(m->data);
+	rpmi_mbox_init_send_with_response(&msg, RPMI_SYSMSI_SRV_SET_MSI_TARGET,
+					  &tx, sizeof(tx), &rx, sizeof(rx));
+	ret = rpmi_mbox_send_message(priv->chan, &msg);
+	if (ret)
+		return ret;
+	if (rx.status)
+		return rpmi_to_linux_error(le32_to_cpu(rx.status));
+
+	return 0;
+}
+
+static void rpmi_sysmsi_irq_mask(struct irq_data *d)
+{
+	struct rpmi_sysmsi_priv *priv = irq_data_get_irq_chip_data(d);
+	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+	int ret;
+
+	ret = rpmi_sysmsi_set_msi_state(priv, hwirq, 0);
+	if (ret)
+		dev_warn(priv->dev, "Failed to mask hwirq %lu (error %d)\n", hwirq, ret);
+	irq_chip_mask_parent(d);
+}
+
+static void rpmi_sysmsi_irq_unmask(struct irq_data *d)
+{
+	struct rpmi_sysmsi_priv *priv = irq_data_get_irq_chip_data(d);
+	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+	int ret;
+
+	irq_chip_unmask_parent(d);
+	ret = rpmi_sysmsi_set_msi_state(priv, hwirq, RPMI_SYSMSI_MSI_STATE_ENABLE);
+	if (ret)
+		dev_warn(priv->dev, "Failed to unmask hwirq %lu (error %d)\n", hwirq, ret);
+}
+
+static void rpmi_sysmsi_write_msg(struct irq_data *d, struct msi_msg *msg)
+{
+	struct rpmi_sysmsi_priv *priv = irq_data_get_irq_chip_data(d);
+	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+	int ret;
+
+	/* For zeroed MSI, do nothing as of now */
+	if (!msg->address_hi && !msg->address_lo && !msg->data)
+		return;
+
+	ret = rpmi_sysmsi_set_msi_target(priv, hwirq, msg);
+	if (ret)
+		dev_warn(priv->dev, "Failed to set target for hwirq %lu (error %d)\n", hwirq, ret);
+}
+
+static void rpmi_sysmsi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+	arg->desc = desc;
+	arg->hwirq = desc->data.icookie.value;
+}
+
+static int rpmi_sysmsi_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
+				 unsigned long *hwirq, unsigned int *type)
+{
+	struct msi_domain_info *info = d->host_data;
+	struct rpmi_sysmsi_priv *priv = info->data;
+
+	if (WARN_ON(fwspec->param_count < 1))
+		return -EINVAL;
+
+	/* For DT, gsi_base is always zero. */
+	*hwirq = fwspec->param[0] - priv->gsi_base;
+	*type = IRQ_TYPE_NONE;
+	return 0;
+}
+
+static const struct msi_domain_template rpmi_sysmsi_template = {
+	.chip = {
+		.name			= "RPMI-SYSMSI",
+		.irq_mask		= rpmi_sysmsi_irq_mask,
+		.irq_unmask		= rpmi_sysmsi_irq_unmask,
+#ifdef CONFIG_SMP
+		.irq_set_affinity	= irq_chip_set_affinity_parent,
+#endif
+		.irq_write_msi_msg	= rpmi_sysmsi_write_msg,
+		.flags			= IRQCHIP_SET_TYPE_MASKED |
+					  IRQCHIP_SKIP_SET_WAKE |
+					  IRQCHIP_MASK_ON_SUSPEND,
+	},
+
+	.ops = {
+		.set_desc		= rpmi_sysmsi_set_desc,
+		.msi_translate		= rpmi_sysmsi_translate,
+	},
+
+	.info = {
+		.bus_token		= DOMAIN_BUS_WIRED_TO_MSI,
+		.flags			= MSI_FLAG_USE_DEV_FWNODE,
+		.handler		= handle_simple_irq,
+		.handler_name		= "simple",
+	},
+};
+
+static int rpmi_sysmsi_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rpmi_sysmsi_priv *priv;
+	int rc;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+	priv->dev = dev;
+
+	/* Setup mailbox client */
+	priv->client.dev		= priv->dev;
+	priv->client.rx_callback	= NULL;
+	priv->client.tx_block		= false;
+	priv->client.knows_txdone	= true;
+	priv->client.tx_tout		= 0;
+
+	/* Request mailbox channel */
+	priv->chan = mbox_request_channel(&priv->client, 0);
+	if (IS_ERR(priv->chan))
+		return PTR_ERR(priv->chan);
+
+	/* Get number of system MSIs */
+	rc = rpmi_sysmsi_get_num_msi(priv);
+	if (rc < 1) {
+		mbox_free_channel(priv->chan);
+		if (rc)
+			return dev_err_probe(dev, rc, "Failed to get number of system MSIs\n");
+		else
+			return dev_err_probe(dev, -ENODEV, "No system MSIs found\n");
+	}
+	priv->nr_irqs = rc;
+
+	/*
+	 * The device MSI domain for platform devices on RISC-V architecture
+	 * is only available after the MSI controller driver is probed so,
+	 * explicitly configure here.
+	 */
+	if (!dev_get_msi_domain(dev)) {
+		/*
+		 * The device MSI domain for OF devices is only set at the
+		 * time of populating/creating OF device. If the device MSI
+		 * domain is discovered later after the OF device is created
+		 * then we need to set it explicitly before using any platform
+		 * MSI functions.
+		 */
+		if (dev_of_node(dev))
+			of_msi_configure(dev, dev_of_node(dev));
+
+		if (!dev_get_msi_domain(dev)) {
+			mbox_free_channel(priv->chan);
+			return -EPROBE_DEFER;
+		}
+	}
+
+	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN,
+					  &rpmi_sysmsi_template,
+					  priv->nr_irqs, priv, priv)) {
+		mbox_free_channel(priv->chan);
+		return dev_err_probe(dev, -ENOMEM, "failed to create MSI irq domain\n");
+	}
+
+	dev_info(dev, "%u system MSIs registered\n", priv->nr_irqs);
+	return 0;
+}
+
+static const struct of_device_id rpmi_sysmsi_match[] = {
+	{ .compatible = "riscv,rpmi-system-msi" },
+	{}
+};
+
+static struct platform_driver rpmi_sysmsi_driver = {
+	.driver = {
+		.name		= "rpmi-sysmsi",
+		.of_match_table	= rpmi_sysmsi_match,
+	},
+	.probe = rpmi_sysmsi_probe,
+};
+builtin_platform_driver(rpmi_sysmsi_driver);
diff --git a/include/linux/mailbox/riscv-rpmi-message.h b/include/linux/mailbox/riscv-rpmi-message.h
index c90918dca367..521a0c9b9b90 100644
--- a/include/linux/mailbox/riscv-rpmi-message.h
+++ b/include/linux/mailbox/riscv-rpmi-message.h
@@ -91,6 +91,7 @@ static inline int rpmi_to_linux_error(int rpmi_error)
 }
 
 /* RPMI service group IDs */
+#define RPMI_SRVGRP_SYSTEM_MSI		0x00002
 #define RPMI_SRVGRP_CLOCK		0x00008
 
 /* RPMI clock service IDs */
@@ -106,6 +107,18 @@ enum rpmi_clock_service_id {
 	RPMI_CLK_SRV_ID_MAX_COUNT
 };
 
+/* RPMI system MSI service IDs */
+enum rpmi_sysmsi_service_id {
+	RPMI_SYSMSI_SRV_ENABLE_NOTIFICATION = 0x01,
+	RPMI_SYSMSI_SRV_GET_ATTRIBUTES = 0x02,
+	RPMI_SYSMSI_SRV_GET_MSI_ATTRIBUTES = 0x03,
+	RPMI_SYSMSI_SRV_SET_MSI_STATE = 0x04,
+	RPMI_SYSMSI_SRV_GET_MSI_STATE = 0x05,
+	RPMI_SYSMSI_SRV_SET_MSI_TARGET = 0x06,
+	RPMI_SYSMSI_SRV_GET_MSI_TARGET = 0x07,
+	RPMI_SYSMSI_SRV_ID_MAX_COUNT
+};
+
 /* RPMI Linux mailbox attribute IDs */
 enum rpmi_mbox_attribute_id {
 	RPMI_MBOX_ATTR_SPEC_VERSION,
-- 
2.43.0

[PATCH v8 14/24] ACPI: property: Refactor acpi_fwnode_get_reference_args() to support nargs_prop

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Currently, acpi_fwnode_get_reference_args() delegates to the internal
function __acpi_node_get_property_reference() to retrieve property
references. However, this function does not handle the nargs_prop (cells
property) parameter, and instead expects the number of arguments (nargs)
to be known or hardcoded.

As a result, when fwnode_property_get_reference_args() is used with a
valid nargs_prop, the ACPI backend ignores it, whereas the Device Tree
(DT) backend uses the #*-cells property from the reference node to
determine the number of arguments dynamically.

To support the nargs_prop in ACPI, refactor the code as follows:

- Move the implementation from __acpi_node_get_property_reference()
  into acpi_fwnode_get_reference_args().

- Update __acpi_node_get_property_reference() to call the (now updated)
  acpi_fwnode_get_reference_args() passing NULL as nargs_prop to keep
  the behavior of __acpi_node_get_property_reference() intact.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/acpi/property.c | 101 ++++++++++++++++++++--------------------
 1 file changed, 50 insertions(+), 51 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 436019d96027..d4863746fb11 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -882,45 +882,10 @@ static struct fwnode_handle *acpi_parse_string_ref(const struct fwnode_handle *f
 	return &dn->fwnode;
 }
 
-/**
- * __acpi_node_get_property_reference - returns handle to the referenced object
- * @fwnode: Firmware node to get the property from
- * @propname: Name of the property
- * @index: Index of the reference to return
- * @num_args: Maximum number of arguments after each reference
- * @args: Location to store the returned reference with optional arguments
- *	  (may be NULL)
- *
- * Find property with @name, verifify that it is a package containing at least
- * one object reference and if so, store the ACPI device object pointer to the
- * target object in @args->adev.  If the reference includes arguments, store
- * them in the @args->args[] array.
- *
- * If there's more than one reference in the property value package, @index is
- * used to select the one to return.
- *
- * It is possible to leave holes in the property value set like in the
- * example below:
- *
- * Package () {
- *     "cs-gpios",
- *     Package () {
- *        ^GPIO, 19, 0, 0,
- *        ^GPIO, 20, 0, 0,
- *        0,
- *        ^GPIO, 21, 0, 0,
- *     }
- * }
- *
- * Calling this function with index %2 or index %3 return %-ENOENT. If the
- * property does not contain any more values %-ENOENT is returned. The NULL
- * entry must be single integer and preferably contain value %0.
- *
- * Return: %0 on success, negative error code on failure.
- */
-int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
-	const char *propname, size_t index, size_t num_args,
-	struct fwnode_reference_args *args)
+static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
+					  const char *propname, const char *nargs_prop,
+					  unsigned int args_count, unsigned int index,
+					  struct fwnode_reference_args *args)
 {
 	const union acpi_object *element, *end;
 	const union acpi_object *obj;
@@ -999,7 +964,7 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 
 			ret = acpi_get_ref_args(idx == index ? args : NULL,
 						acpi_fwnode_handle(device),
-						&element, end, num_args);
+						&element, end, args_count);
 			if (ret < 0)
 				return ret;
 
@@ -1017,7 +982,7 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 
 			ret = acpi_get_ref_args(idx == index ? args : NULL,
 						ref_fwnode, &element, end,
-						num_args);
+						args_count);
 			if (ret < 0)
 				return ret;
 
@@ -1039,6 +1004,50 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 
 	return -ENOENT;
 }
+
+/**
+ * __acpi_node_get_property_reference - returns handle to the referenced object
+ * @fwnode: Firmware node to get the property from
+ * @propname: Name of the property
+ * @index: Index of the reference to return
+ * @num_args: Maximum number of arguments after each reference
+ * @args: Location to store the returned reference with optional arguments
+ *	  (may be NULL)
+ *
+ * Find property with @name, verifify that it is a package containing at least
+ * one object reference and if so, store the ACPI device object pointer to the
+ * target object in @args->adev.  If the reference includes arguments, store
+ * them in the @args->args[] array.
+ *
+ * If there's more than one reference in the property value package, @index is
+ * used to select the one to return.
+ *
+ * It is possible to leave holes in the property value set like in the
+ * example below:
+ *
+ * Package () {
+ *     "cs-gpios",
+ *     Package () {
+ *        ^GPIO, 19, 0, 0,
+ *        ^GPIO, 20, 0, 0,
+ *        0,
+ *        ^GPIO, 21, 0, 0,
+ *     }
+ * }
+ *
+ * Calling this function with index %2 or index %3 return %-ENOENT. If the
+ * property does not contain any more values %-ENOENT is returned. The NULL
+ * entry must be single integer and preferably contain value %0.
+ *
+ * Return: %0 on success, negative error code on failure.
+ */
+int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
+				       const char *propname, size_t index,
+				       size_t num_args,
+				       struct fwnode_reference_args *args)
+{
+	return acpi_fwnode_get_reference_args(fwnode, propname, NULL, index, num_args, args);
+}
 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
 
 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
@@ -1558,16 +1567,6 @@ acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
 				   val, nval);
 }
 
-static int
-acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
-			       const char *prop, const char *nargs_prop,
-			       unsigned int args_count, unsigned int index,
-			       struct fwnode_reference_args *args)
-{
-	return __acpi_node_get_property_reference(fwnode, prop, index,
-						  args_count, args);
-}
-
 static const char *acpi_fwnode_get_name(const struct fwnode_handle *fwnode)
 {
 	const struct acpi_device *adev;
-- 
2.43.0

[PATCH v8 15/24] ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Currently, ACPI does not support the use of a nargs_prop (e.g.,
associated with a reference in fwnode_property_get_reference_args().
Instead, ACPI expects the number of arguments (nargs) to be explicitly
passed or known.

This behavior diverges from Open Firmware (OF), which allows the use of
a #*-cells property in the referenced node to determine the number of
arguments. Since fwnode_property_get_reference_args() is a common
interface used across both OF and ACPI firmware paradigms, it is
desirable to have a unified calling convention that works seamlessly for
both.

Add the support for ACPI to parse a nargs_prop from the referenced
fwnode, aligning its behavior with the OF backend. This allows drivers
and subsystems using fwnode_property_get_reference_args() to work in a
firmware-agnostic way without having to hardcode or special-case
argument counts for ACPI.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/acpi/property.c | 29 +++++++++++++++++++++++++----
 drivers/base/property.c |  2 +-
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index d4863746fb11..e92402deee77 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -804,13 +804,35 @@ acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
 	return NULL;
 }
 
+static unsigned int acpi_fwnode_get_args_count(struct fwnode_handle *fwnode,
+					       const char *nargs_prop)
+{
+	const struct acpi_device_data *data;
+	const union acpi_object *obj;
+	int ret;
+
+	data = acpi_device_data_of_node(fwnode);
+	if (!data)
+		return 0;
+
+	ret = acpi_data_get_property(data, nargs_prop, ACPI_TYPE_INTEGER, &obj);
+	if (ret)
+		return 0;
+
+	return obj->integer.value;
+}
+
 static int acpi_get_ref_args(struct fwnode_reference_args *args,
 			     struct fwnode_handle *ref_fwnode,
+			     const char *nargs_prop,
 			     const union acpi_object **element,
 			     const union acpi_object *end, size_t num_args)
 {
 	u32 nargs = 0, i;
 
+	if (nargs_prop)
+		num_args = acpi_fwnode_get_args_count(ref_fwnode, nargs_prop);
+
 	/*
 	 * Assume the following integer elements are all args. Stop counting on
 	 * the first reference (possibly represented as a string) or end of the
@@ -961,10 +983,10 @@ static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
 				return -EINVAL;
 
 			element++;
-
 			ret = acpi_get_ref_args(idx == index ? args : NULL,
 						acpi_fwnode_handle(device),
-						&element, end, args_count);
+						nargs_prop, &element, end,
+						args_count);
 			if (ret < 0)
 				return ret;
 
@@ -979,9 +1001,8 @@ static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
 				return -EINVAL;
 
 			element++;
-
 			ret = acpi_get_ref_args(idx == index ? args : NULL,
-						ref_fwnode, &element, end,
+						ref_fwnode, nargs_prop, &element, end,
 						args_count);
 			if (ret < 0)
 				return ret;
diff --git a/drivers/base/property.c b/drivers/base/property.c
index f626d5bbe806..6a63860579dd 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -578,7 +578,7 @@ EXPORT_SYMBOL_GPL(fwnode_property_match_property_string);
  * @prop:	The name of the property
  * @nargs_prop:	The name of the property telling the number of
  *		arguments in the referred node. NULL if @nargs is known,
- *		otherwise @nargs is ignored. Only relevant on OF.
+ *		otherwise @nargs is ignored.
  * @nargs:	Number of arguments. Ignored if @nargs_prop is non-NULL.
  * @index:	Index of the reference, from zero onwards.
  * @args:	Result structure with reference and integer arguments.
-- 
2.43.0

[PATCH v8 16/24] ACPI: scan: Update honor list for RPMI System MSI

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

The RPMI System MSI interrupt controller (just like PLIC and APLIC)
needs to probed prior to devices like GED which use interrupts provided
by it. Also, it has dependency on the SBI MPXY mailbox device.

Add HIDs of RPMI System MSI and SBI MPXY mailbox devices to the honor
list so that those dependencies are handled.

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/acpi/scan.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index fb1fe9f3b1a3..54181b03b345 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -858,6 +858,8 @@ static const char * const acpi_honor_dep_ids[] = {
 	"INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */
 	"RSCV0001", /* RISC-V PLIC */
 	"RSCV0002", /* RISC-V APLIC */
+	"RSCV0005", /* RISC-V SBI MPXY MBOX */
+	"RSCV0006", /* RISC-V RPMI SYSMSI */
 	"PNP0C0F",  /* PCI Link Device */
 	NULL
 };
-- 
2.43.0

[PATCH v8 17/24] ACPI: RISC-V: Create interrupt controller list in sorted order

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Currently, the interrupt controller list is created without any order.
Create the list sorted with the GSI base of the interrupt controllers.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/acpi/riscv/irq.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
index cced960c2aef..33c073e2e71d 100644
--- a/drivers/acpi/riscv/irq.c
+++ b/drivers/acpi/riscv/irq.c
@@ -115,7 +115,7 @@ struct fwnode_handle *riscv_acpi_get_gsi_domain_id(u32 gsi)
 static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr_idcs,
 					       u32 id, u32 type)
 {
-	struct riscv_ext_intc_list *ext_intc_element;
+	struct riscv_ext_intc_list *ext_intc_element, *node;
 
 	ext_intc_element = kzalloc(sizeof(*ext_intc_element), GFP_KERNEL);
 	if (!ext_intc_element)
@@ -125,7 +125,12 @@ static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr
 	ext_intc_element->nr_irqs = nr_irqs;
 	ext_intc_element->nr_idcs = nr_idcs;
 	ext_intc_element->id = id;
-	list_add_tail(&ext_intc_element->list, &ext_intc_list);
+	list_for_each_entry(node, &ext_intc_list, list) {
+		if (node->gsi_base < ext_intc_element->gsi_base)
+			break;
+	}
+
+	list_add_tail(&ext_intc_element->list, &node->list);
 	return 0;
 }
 
-- 
2.43.0

[PATCH v8 18/24] ACPI: RISC-V: Add support to update gsi range

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Some RISC-V interrupt controllers like RPMI based system MSI interrupt
controllers do not have MADT entry defined. These interrupt controllers
exist only in the namespace. ACPI spec defines _GSB method to get the
GSI base of the interrupt controller, However, there is no such standard
method to get the GSI range. To support such interrupt controllers, set
the GSI range of such interrupt controllers to non-overlapping range and
provide API for interrupt controller driver to update it with proper
value.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/include/asm/irq.h |  5 +++++
 drivers/acpi/riscv/irq.c     | 38 ++++++++++++++++++++++++++++++++++--
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/irq.h b/arch/riscv/include/asm/irq.h
index 7b038f3b7cb0..2caf049f09c8 100644
--- a/arch/riscv/include/asm/irq.h
+++ b/arch/riscv/include/asm/irq.h
@@ -40,6 +40,7 @@ unsigned long acpi_rintc_ext_parent_to_hartid(unsigned int plic_id, unsigned int
 unsigned int acpi_rintc_get_plic_nr_contexts(unsigned int plic_id);
 unsigned int acpi_rintc_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx);
 int __init acpi_rintc_get_imsic_mmio_info(u32 index, struct resource *res);
+int riscv_acpi_update_gsi_range(u32 gsi_base, u32 nr_irqs);
 
 #else
 static inline int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
@@ -74,6 +75,10 @@ static inline int __init acpi_rintc_get_imsic_mmio_info(u32 index, struct resour
 	return 0;
 }
 
+static inline int riscv_acpi_update_gsi_range(u32 gsi_base, u32 nr_irqs)
+{
+	return -ENODEV;
+}
 #endif /* CONFIG_ACPI */
 
 #endif /* _ASM_RISCV_IRQ_H */
diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
index 33c073e2e71d..cc1928422418 100644
--- a/drivers/acpi/riscv/irq.c
+++ b/drivers/acpi/riscv/irq.c
@@ -10,6 +10,8 @@
 
 #include "init.h"
 
+#define RISCV_ACPI_INTC_FLAG_PENDING BIT(0)
+
 struct riscv_ext_intc_list {
 	acpi_handle		handle;
 	u32			gsi_base;
@@ -17,6 +19,7 @@ struct riscv_ext_intc_list {
 	u32			nr_idcs;
 	u32			id;
 	u32			type;
+	u32			flag;
 	struct list_head	list;
 };
 
@@ -69,6 +72,22 @@ static acpi_status riscv_acpi_update_gsi_handle(u32 gsi_base, acpi_handle handle
 	return AE_NOT_FOUND;
 }
 
+int riscv_acpi_update_gsi_range(u32 gsi_base, u32 nr_irqs)
+{
+	struct riscv_ext_intc_list *ext_intc_element;
+
+	list_for_each_entry(ext_intc_element, &ext_intc_list, list) {
+		if (gsi_base == ext_intc_element->gsi_base &&
+		    (ext_intc_element->flag & RISCV_ACPI_INTC_FLAG_PENDING)) {
+			ext_intc_element->nr_irqs = nr_irqs;
+			ext_intc_element->flag &= ~RISCV_ACPI_INTC_FLAG_PENDING;
+			return 0;
+		}
+	}
+
+	return -ENODEV;
+}
+
 int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
 			    u32 *id, u32 *nr_irqs, u32 *nr_idcs)
 {
@@ -115,14 +134,22 @@ struct fwnode_handle *riscv_acpi_get_gsi_domain_id(u32 gsi)
 static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr_idcs,
 					       u32 id, u32 type)
 {
-	struct riscv_ext_intc_list *ext_intc_element, *node;
+	struct riscv_ext_intc_list *ext_intc_element, *node, *prev;
 
 	ext_intc_element = kzalloc(sizeof(*ext_intc_element), GFP_KERNEL);
 	if (!ext_intc_element)
 		return -ENOMEM;
 
 	ext_intc_element->gsi_base = gsi_base;
-	ext_intc_element->nr_irqs = nr_irqs;
+
+	/* If nr_irqs is zero, indicate it in flag and set to max range possible */
+	if (nr_irqs) {
+		ext_intc_element->nr_irqs = nr_irqs;
+	} else {
+		ext_intc_element->flag |= RISCV_ACPI_INTC_FLAG_PENDING;
+		ext_intc_element->nr_irqs = U32_MAX - ext_intc_element->gsi_base;
+	}
+
 	ext_intc_element->nr_idcs = nr_idcs;
 	ext_intc_element->id = id;
 	list_for_each_entry(node, &ext_intc_list, list) {
@@ -130,6 +157,13 @@ static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr
 			break;
 	}
 
+	/* Adjust the previous node's GSI range if that has pending registration */
+	prev = list_prev_entry(node, list);
+	if (!list_entry_is_head(prev, &ext_intc_list, list)) {
+		if (prev->flag & RISCV_ACPI_INTC_FLAG_PENDING)
+			prev->nr_irqs = ext_intc_element->gsi_base - prev->gsi_base;
+	}
+
 	list_add_tail(&ext_intc_element->list, &node->list);
 	return 0;
 }
-- 
2.43.0

[PATCH v8 19/24] ACPI: RISC-V: Add RPMI System MSI to GSI mapping

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

The RPMI System MSI device will provide GSIs to downstream devices
(such as GED) so add it to the RISC-V GSI to fwnode mapping.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/include/asm/irq.h |  1 +
 drivers/acpi/riscv/irq.c     | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/arch/riscv/include/asm/irq.h b/arch/riscv/include/asm/irq.h
index 2caf049f09c8..9c9d22f5165e 100644
--- a/arch/riscv/include/asm/irq.h
+++ b/arch/riscv/include/asm/irq.h
@@ -30,6 +30,7 @@ enum riscv_irqchip_type {
 	ACPI_RISCV_IRQCHIP_IMSIC	= 0x01,
 	ACPI_RISCV_IRQCHIP_PLIC		= 0x02,
 	ACPI_RISCV_IRQCHIP_APLIC	= 0x03,
+	ACPI_RISCV_IRQCHIP_SMSI		= 0x04,
 };
 
 int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
index cc1928422418..d9a2154d6c6a 100644
--- a/drivers/acpi/riscv/irq.c
+++ b/drivers/acpi/riscv/irq.c
@@ -168,6 +168,33 @@ static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr
 	return 0;
 }
 
+static acpi_status __init riscv_acpi_create_gsi_map_smsi(acpi_handle handle, u32 level,
+							 void *context, void **return_value)
+{
+	acpi_status status;
+	u64 gbase;
+
+	if (!acpi_has_method(handle, "_GSB")) {
+		acpi_handle_err(handle, "_GSB method not found\n");
+		return AE_ERROR;
+	}
+
+	status = acpi_evaluate_integer(handle, "_GSB", NULL, &gbase);
+	if (ACPI_FAILURE(status)) {
+		acpi_handle_err(handle, "failed to evaluate _GSB method\n");
+		return status;
+	}
+
+	riscv_acpi_register_ext_intc(gbase, 0, 0, 0, ACPI_RISCV_IRQCHIP_SMSI);
+	status = riscv_acpi_update_gsi_handle((u32)gbase, handle);
+	if (ACPI_FAILURE(status)) {
+		acpi_handle_err(handle, "failed to find the GSI mapping entry\n");
+		return status;
+	}
+
+	return AE_OK;
+}
+
 static acpi_status __init riscv_acpi_create_gsi_map(acpi_handle handle, u32 level,
 						    void *context, void **return_value)
 {
@@ -222,6 +249,9 @@ void __init riscv_acpi_init_gsi_mapping(void)
 
 	if (acpi_table_parse_madt(ACPI_MADT_TYPE_APLIC, riscv_acpi_aplic_parse_madt, 0) > 0)
 		acpi_get_devices("RSCV0002", riscv_acpi_create_gsi_map, NULL, NULL);
+
+	/* Unlike PLIC/APLIC, SYSMSI doesn't have MADT */
+	acpi_get_devices("RSCV0006", riscv_acpi_create_gsi_map_smsi, NULL, NULL);
 }
 
 static acpi_handle riscv_acpi_get_gsi_handle(u32 gsi)
-- 
2.43.0

[PATCH v8 20/24] irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

ACPI based loadable drivers which need MSIs will also need
imsic_acpi_get_fwnode() to update the device MSI domain so
export this function.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/irqchip/irq-riscv-imsic-early.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/irqchip/irq-riscv-imsic-early.c b/drivers/irqchip/irq-riscv-imsic-early.c
index d9ae87808651..1dbc41d7fe80 100644
--- a/drivers/irqchip/irq-riscv-imsic-early.c
+++ b/drivers/irqchip/irq-riscv-imsic-early.c
@@ -7,6 +7,7 @@
 #define pr_fmt(fmt) "riscv-imsic: " fmt
 #include <linux/acpi.h>
 #include <linux/cpu.h>
+#include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -215,6 +216,7 @@ struct fwnode_handle *imsic_acpi_get_fwnode(struct device *dev)
 {
 	return imsic_acpi_fwnode;
 }
+EXPORT_SYMBOL_GPL(imsic_acpi_get_fwnode);
 
 static int __init imsic_early_acpi_init(union acpi_subtable_headers *header,
 					const unsigned long end)
-- 
2.43.0

[PATCH v8 21/24] mailbox/riscv-sbi-mpxy: Add ACPI support

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Add ACPI support for the RISC-V SBI message proxy (MPXY) based
mailbox driver.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/mailbox/riscv-sbi-mpxy-mbox.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/mailbox/riscv-sbi-mpxy-mbox.c b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
index 1a8a74d3ad4b..a739088c3d4c 100644
--- a/drivers/mailbox/riscv-sbi-mpxy-mbox.c
+++ b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
@@ -5,9 +5,11 @@
  * Copyright (C) 2025 Ventana Micro Systems Inc.
  */
 
+#include <linux/acpi.h>
 #include <linux/cpu.h>
 #include <linux/errno.h>
 #include <linux/init.h>
+#include <linux/irqchip/riscv-imsic.h>
 #include <linux/mailbox_controller.h>
 #include <linux/mailbox/riscv-rpmi-message.h>
 #include <linux/minmax.h>
@@ -902,6 +904,8 @@ static int mpxy_mbox_probe(struct platform_device *pdev)
 	 * explicitly configure here.
 	 */
 	if (!dev_get_msi_domain(dev)) {
+		struct fwnode_handle *fwnode = dev_fwnode(dev);
+
 		/*
 		 * The device MSI domain for OF devices is only set at the
 		 * time of populating/creating OF device. If the device MSI
@@ -909,8 +913,15 @@ static int mpxy_mbox_probe(struct platform_device *pdev)
 		 * then we need to set it explicitly before using any platform
 		 * MSI functions.
 		 */
-		if (dev_of_node(dev))
+		if (is_of_node(fwnode)) {
 			of_msi_configure(dev, dev_of_node(dev));
+		} else if (is_acpi_device_node(fwnode)) {
+			struct irq_domain *msi_domain;
+
+			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
+							      DOMAIN_BUS_PLATFORM_MSI);
+			dev_set_msi_domain(dev, msi_domain);
+		}
 
 		if (!dev_get_msi_domain(dev))
 			return -EPROBE_DEFER;
@@ -958,6 +969,13 @@ static int mpxy_mbox_probe(struct platform_device *pdev)
 		return rc;
 	}
 
+#ifdef CONFIG_ACPI
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (adev)
+		acpi_dev_clear_dependencies(adev);
+#endif
+
 	dev_info(dev, "mailbox registered with %d channels\n",
 		 mbox->channel_count);
 	return 0;
@@ -977,10 +995,17 @@ static const struct of_device_id mpxy_mbox_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, mpxy_mbox_of_match);
 
+static const struct acpi_device_id mpxy_mbox_acpi_match[] = {
+	{ "RSCV0005" },
+	{}
+};
+MODULE_DEVICE_TABLE(acpi, mpxy_mbox_acpi_match);
+
 static struct platform_driver mpxy_mbox_driver = {
 	.driver = {
 		.name = "riscv-sbi-mpxy-mbox",
 		.of_match_table = mpxy_mbox_of_match,
+		.acpi_match_table = mpxy_mbox_acpi_match,
 	},
 	.probe = mpxy_mbox_probe,
 	.remove = mpxy_mbox_remove,
-- 
2.43.0

[PATCH v8 22/24] irqchip/riscv-rpmi-sysmsi: Add ACPI support

[Anup Patel]

From: Sunil V L <sunilvl@ventanamicro.com>

Add ACPI support for the RISC-V RPMI system MSI based irqchip driver.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/irqchip/Kconfig                 |  2 +-
 drivers/irqchip/irq-riscv-rpmi-sysmsi.c | 47 +++++++++++++++++++++++--
 2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 96bf6aa55681..dfa8cc0e23dd 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -619,7 +619,7 @@ config RISCV_IMSIC
 
 config RISCV_RPMI_SYSMSI
 	bool
-	depends on MAILBOX
+	depends on RISCV && MAILBOX
 	select IRQ_DOMAIN_HIERARCHY
 	select GENERIC_MSI_IRQ
 	default RISCV
diff --git a/drivers/irqchip/irq-riscv-rpmi-sysmsi.c b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
index 92e8847dfccc..5c74c561ce31 100644
--- a/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
+++ b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) 2025 Ventana Micro Systems Inc. */
 
+#include <linux/acpi.h>
 #include <linux/bits.h>
 #include <linux/bug.h>
 #include <linux/device.h>
@@ -9,6 +10,7 @@
 #include <linux/errno.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
+#include <linux/irqchip/riscv-imsic.h>
 #include <linux/mailbox_client.h>
 #include <linux/mailbox/riscv-rpmi-message.h>
 #include <linux/module.h>
@@ -209,6 +211,8 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct rpmi_sysmsi_priv *priv;
+	struct fwnode_handle *fwnode;
+	u32 id;
 	int rc;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -239,6 +243,22 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 	}
 	priv->nr_irqs = rc;
 
+	fwnode = dev_fwnode(dev);
+	if (is_acpi_node(fwnode)) {
+		u32 nr_irqs;
+
+		rc = riscv_acpi_get_gsi_info(fwnode, &priv->gsi_base, &id,
+					     &nr_irqs, NULL);
+		if (rc) {
+			dev_err(dev, "failed to find GSI mapping\n");
+			return rc;
+		}
+
+		/* Update with actual GSI range */
+		if (nr_irqs != priv->nr_irqs)
+			riscv_acpi_update_gsi_range(priv->gsi_base, priv->nr_irqs);
+	}
+
 	/*
 	 * The device MSI domain for platform devices on RISC-V architecture
 	 * is only available after the MSI controller driver is probed so,
@@ -252,8 +272,15 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 		 * then we need to set it explicitly before using any platform
 		 * MSI functions.
 		 */
-		if (dev_of_node(dev))
+		if (is_of_node(fwnode)) {
 			of_msi_configure(dev, dev_of_node(dev));
+		} else if (is_acpi_device_node(fwnode)) {
+			struct irq_domain *msi_domain;
+
+			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
+							      DOMAIN_BUS_PLATFORM_MSI);
+			dev_set_msi_domain(dev, msi_domain);
+		}
 
 		if (!dev_get_msi_domain(dev)) {
 			mbox_free_channel(priv->chan);
@@ -268,6 +295,13 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, -ENOMEM, "failed to create MSI irq domain\n");
 	}
 
+#ifdef CONFIG_ACPI
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (adev)
+		acpi_dev_clear_dependencies(adev);
+#endif
+
 	dev_info(dev, "%u system MSIs registered\n", priv->nr_irqs);
 	return 0;
 }
@@ -277,10 +311,17 @@ static const struct of_device_id rpmi_sysmsi_match[] = {
 	{}
 };
 
+static const struct acpi_device_id acpi_rpmi_sysmsi_match[] = {
+	{ "RSCV0006" },
+	{}
+};
+MODULE_DEVICE_TABLE(acpi, acpi_rpmi_sysmsi_match);
+
 static struct platform_driver rpmi_sysmsi_driver = {
 	.driver = {
-		.name		= "rpmi-sysmsi",
-		.of_match_table	= rpmi_sysmsi_match,
+		.name			= "rpmi-sysmsi",
+		.of_match_table		= rpmi_sysmsi_match,
+		.acpi_match_table	= acpi_rpmi_sysmsi_match,
 	},
 	.probe = rpmi_sysmsi_probe,
 };
-- 
2.43.0

[PATCH v8 23/24] RISC-V: Enable GPIO keyboard and event device in RV64 defconfig

[Anup Patel]

The GPIO keyboard and event device can be used to receive graceful
shutdown or reboot input keys so let us enable it by default for
RV64 (just like ARM64).

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/configs/defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index fe8bd8afb418..bd5f97e1d1a0 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -138,6 +138,8 @@ CONFIG_MICREL_PHY=y
 CONFIG_MICROSEMI_PHY=y
 CONFIG_MOTORCOMM_PHY=y
 CONFIG_INPUT_MOUSEDEV=y
+CONFIG_INPUT_EVDEV=y
+CONFIG_KEYBOARD_GPIO=y
 CONFIG_KEYBOARD_SUN4I_LRADC=m
 CONFIG_SERIAL_8250=y
 CONFIG_SERIAL_8250_CONSOLE=y
-- 
2.43.0

[PATCH v8 24/24] MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers

[Anup Patel]

Add Rahul and myself as maintainers for RISC-V RPMI and MPXY drivers.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 MAINTAINERS | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 4bac4ea21b64..c22434a2756b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21397,6 +21397,21 @@ F:	drivers/perf/riscv_pmu.c
 F:	drivers/perf/riscv_pmu_legacy.c
 F:	drivers/perf/riscv_pmu_sbi.c
 
+RISC-V RPMI AND MPXY DRIVERS
+M:	Rahul Pathak <rahul@summations.net>
+M:	Anup Patel <anup@brainfault.org>
+L:	linux-riscv@lists.infradead.org
+F:	Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
+F:	Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
+F:	Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
+F:	Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
+F:	Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
+F:	Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
+F:	drivers/clk/clk-rpmi.c
+F:	drivers/irqchip/irq-riscv-rpmi-sysmsi.c
+F:	drivers/mailbox/riscv-sbi-mpxy-mbox.c
+F:	include/linux/mailbox/riscv-rpmi-message.h
+
 RISC-V SPACEMIT SoC Support
 M:	Yixun Lan <dlan@gentoo.org>
 L:	linux-riscv@lists.infradead.org
-- 
2.43.0

Re: [PATCH v8 05/24] mailbox: Allow controller specific mapping using fwnode

[Anup Patel]

On Fri, Jul 4, 2025 at 12:35 PM Anup Patel <apatel@ventanamicro.com> wrote:
>
> Introduce optional fw_node() callback which allows a mailbox controller
> driver to provide controller specific mapping using fwnode.
>
> The Linux OF framework already implements fwnode operations for the
> Linux DD framework so the fw_xlate() callback works fine with device
> tree as well.
>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>

I missed adding Andy's Reviewed-by here which I will do in the
next revision.

Regards,
Anup

> ---
>  drivers/mailbox/mailbox.c          | 65 ++++++++++++++++++------------
>  include/linux/mailbox_controller.h |  3 ++
>  2 files changed, 43 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
> index 5cd8ae222073..2acc6ec229a4 100644
> --- a/drivers/mailbox/mailbox.c
> +++ b/drivers/mailbox/mailbox.c
> @@ -15,6 +15,7 @@
>  #include <linux/module.h>
>  #include <linux/mutex.h>
>  #include <linux/of.h>
> +#include <linux/property.h>
>  #include <linux/spinlock.h>
>
>  #include "mailbox.h"
> @@ -383,34 +384,56 @@ EXPORT_SYMBOL_GPL(mbox_bind_client);
>   */
>  struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
>  {
> -       struct device *dev = cl->dev;
> +       struct fwnode_reference_args fwspec;
> +       struct fwnode_handle *fwnode;
>         struct mbox_controller *mbox;
>         struct of_phandle_args spec;
>         struct mbox_chan *chan;
> +       struct device *dev;
> +       unsigned int i;
>         int ret;
>
> -       if (!dev || !dev->of_node) {
> -               pr_debug("%s: No owner device node\n", __func__);
> +       dev = cl->dev;
> +       if (!dev) {
> +               pr_debug("No owner device\n");
>                 return ERR_PTR(-ENODEV);
>         }
>
> -       ret = of_parse_phandle_with_args(dev->of_node, "mboxes", "#mbox-cells",
> -                                        index, &spec);
> +       fwnode = dev_fwnode(dev);
> +       if (!fwnode) {
> +               dev_dbg(dev, "No owner fwnode\n");
> +               return ERR_PTR(-ENODEV);
> +       }
> +
> +       ret = fwnode_property_get_reference_args(fwnode, "mboxes", "#mbox-cells",
> +                                                0, index, &fwspec);
>         if (ret) {
> -               dev_err(dev, "%s: can't parse \"mboxes\" property\n", __func__);
> +               dev_err(dev, "%s: can't parse \"%s\" property\n", __func__, "mboxes");
>                 return ERR_PTR(ret);
>         }
>
> +       spec.np = to_of_node(fwspec.fwnode);
> +       spec.args_count = fwspec.nargs;
> +       for (i = 0; i < spec.args_count; i++)
> +               spec.args[i] = fwspec.args[i];
> +
>         scoped_guard(mutex, &con_mutex) {
>                 chan = ERR_PTR(-EPROBE_DEFER);
> -               list_for_each_entry(mbox, &mbox_cons, node)
> -                       if (mbox->dev->of_node == spec.np) {
> -                               chan = mbox->of_xlate(mbox, &spec);
> -                               if (!IS_ERR(chan))
> -                                       break;
> +               list_for_each_entry(mbox, &mbox_cons, node) {
> +                       if (device_match_fwnode(mbox->dev, fwspec.fwnode)) {
> +                               if (mbox->fw_xlate) {
> +                                       chan = mbox->fw_xlate(mbox, &fwspec);
> +                                       if (!IS_ERR(chan))
> +                                               break;
> +                               } else if (mbox->of_xlate) {
> +                                       chan = mbox->of_xlate(mbox, &spec);
> +                                       if (!IS_ERR(chan))
> +                                               break;
> +                               }
>                         }
> +               }
>
> -               of_node_put(spec.np);
> +               fwnode_handle_put(fwspec.fwnode);
>
>                 if (IS_ERR(chan))
>                         return chan;
> @@ -427,15 +450,8 @@ EXPORT_SYMBOL_GPL(mbox_request_channel);
>  struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
>                                               const char *name)
>  {
> -       struct device_node *np = cl->dev->of_node;
> -       int index;
> -
> -       if (!np) {
> -               dev_err(cl->dev, "%s() currently only supports DT\n", __func__);
> -               return ERR_PTR(-EINVAL);
> -       }
> +       int index = device_property_match_string(cl->dev, "mbox-names", name);
>
> -       index = of_property_match_string(np, "mbox-names", name);
>         if (index < 0) {
>                 dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
>                         __func__, name);
> @@ -470,9 +486,8 @@ void mbox_free_channel(struct mbox_chan *chan)
>  }
>  EXPORT_SYMBOL_GPL(mbox_free_channel);
>
> -static struct mbox_chan *
> -of_mbox_index_xlate(struct mbox_controller *mbox,
> -                   const struct of_phandle_args *sp)
> +static struct mbox_chan *fw_mbox_index_xlate(struct mbox_controller *mbox,
> +                                            const struct fwnode_reference_args *sp)
>  {
>         int ind = sp->args[0];
>
> @@ -523,8 +538,8 @@ int mbox_controller_register(struct mbox_controller *mbox)
>                 spin_lock_init(&chan->lock);
>         }
>
> -       if (!mbox->of_xlate)
> -               mbox->of_xlate = of_mbox_index_xlate;
> +       if (!mbox->fw_xlate && !mbox->of_xlate)
> +               mbox->fw_xlate = fw_mbox_index_xlate;
>
>         scoped_guard(mutex, &con_mutex)
>                 list_add_tail(&mbox->node, &mbox_cons);
> diff --git a/include/linux/mailbox_controller.h b/include/linux/mailbox_controller.h
> index ad01c4082358..80a427c7ca29 100644
> --- a/include/linux/mailbox_controller.h
> +++ b/include/linux/mailbox_controller.h
> @@ -66,6 +66,7 @@ struct mbox_chan_ops {
>   *                     no interrupt rises. Ignored if 'txdone_irq' is set.
>   * @txpoll_period:     If 'txdone_poll' is in effect, the API polls for
>   *                     last TX's status after these many millisecs
> + * @fw_xlate:          Controller driver specific mapping of channel via fwnode
>   * @of_xlate:          Controller driver specific mapping of channel via DT
>   * @poll_hrt:          API private. hrtimer used to poll for TXDONE on all
>   *                     channels.
> @@ -79,6 +80,8 @@ struct mbox_controller {
>         bool txdone_irq;
>         bool txdone_poll;
>         unsigned txpoll_period;
> +       struct mbox_chan *(*fw_xlate)(struct mbox_controller *mbox,
> +                                     const struct fwnode_reference_args *sp);
>         struct mbox_chan *(*of_xlate)(struct mbox_controller *mbox,
>                                       const struct of_phandle_args *sp);
>         /* Internal to API */
> --
> 2.43.0
>

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Krzysztof Kozlowski]

On Fri, Jul 04, 2025 at 12:33:32PM +0530, Anup Patel wrote:
> The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> are frozen and finished public review at the RISC-V International.
> 
> Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> and RPMI system MSI driver This series also includes ACPI support
> for SBI MPXY mailbox controller and RPMI system MSI drivers.
> 
> These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> at: https://github.com/avpatel/linux.git
> 
> To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> machine with OpenSBI and QEMU from the dev-upstream branch at:
> https://github.com/ventanamicro/opensbi.git
> https://github.com/ventanamicro/qemu.git
> 
> [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
> 
> Changes since v7:
>  - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21

Which comments? What exactly did you change? Provide in-patch changelogs
explaining this, because what you wrote is way too vague.

Best regards,
Krzysztof

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Anup Patel]

On Fri, Jul 4, 2025 at 1:15 PM Krzysztof Kozlowski <krzk@kernel.org> wrote:
>
> On Fri, Jul 04, 2025 at 12:33:32PM +0530, Anup Patel wrote:
> > The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> > are frozen and finished public review at the RISC-V International.
> >
> > Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> > Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> > and RPMI system MSI driver This series also includes ACPI support
> > for SBI MPXY mailbox controller and RPMI system MSI drivers.
> >
> > These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> > at: https://github.com/avpatel/linux.git
> >
> > To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> > machine with OpenSBI and QEMU from the dev-upstream branch at:
> > https://github.com/ventanamicro/opensbi.git
> > https://github.com/ventanamicro/qemu.git
> >
> > [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> > [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
> >
> > Changes since v7:
> >  - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21
>
> Which comments? What exactly did you change? Provide in-patch changelogs
> explaining this, because what you wrote is way too vague.
>

Apologies for being a bit lazy here. Most changes are pretty straight forward
except the improvements in PATCH14. More detailed change log is below ...

Changes since v7:
 - Addressed enum related nits in PATCH3
   (Refer, https://lore.kernel.org/all/CAK9=C2VxhC6soxHtmacedbeCU=rFi84Br1RvN2uPcBKoLhRaJw@mail.gmail.com/)
 - Addressed comments in PATCH7 as follows:
   - Added minmax.h to includes
   - Removed "rc" variable from mpxy_mbox_send_rpmi_data()
   - Removed alignment and other checks from mpxy_mbox_peek_rpmi_data()
   - Created separate function to restrict scope of channel_ids used
in mpxy_mbox_probe()
   (Refer, https://lore.kernel.org/all/CAK9=C2Ume2CmBYHYob7HSJHu=ZdfdWM+4JYPgFJ9Hir5Oi8cOg@mail.gmail.com/)
 - Improved comments for struct rpmi_clk_rates in PATCH10
   (Refer, https://lore.kernel.org/all/CAK9=C2VfvsbFTjecQm0OSsssXbff7wC4fqWf3CTmnpWSiaLcBw@mail.gmail.com/)
 - Improved refactoring of acpi_fwnode_get_reference_args() in PATCH14
   (Refer, https://lore.kernel.org/all/20250702051345.1460497-15-apatel@ventanamicro.com/)
 - Improve nargs_count parsing in acpi_fwnode_get_reference_args() for PATCH15
   (Refer, https://lore.kernel.org/all/20250702051345.1460497-16-apatel@ventanamicro.com/)
 - Added more comments describing why need to explicitly set device
MSI domain in PATCH21
   (Refer, https://lore.kernel.org/all/aGaUmpw1pVWNAmpb@smile.fi.intel.com/)

Regards,
Anup

Re: [PATCH v8 14/24] ACPI: property: Refactor acpi_fwnode_get_reference_args() to support nargs_prop

[Rafael J. Wysocki]

On Fri, Jul 4, 2025 at 9:07 AM Anup Patel <apatel@ventanamicro.com> wrote:
>
> From: Sunil V L <sunilvl@ventanamicro.com>
>
> Currently, acpi_fwnode_get_reference_args() delegates to the internal
> function __acpi_node_get_property_reference() to retrieve property
> references. However, this function does not handle the nargs_prop (cells
> property) parameter, and instead expects the number of arguments (nargs)
> to be known or hardcoded.
>
> As a result, when fwnode_property_get_reference_args() is used with a
> valid nargs_prop, the ACPI backend ignores it, whereas the Device Tree
> (DT) backend uses the #*-cells property from the reference node to
> determine the number of arguments dynamically.
>
> To support the nargs_prop in ACPI, refactor the code as follows:
>
> - Move the implementation from __acpi_node_get_property_reference()
>   into acpi_fwnode_get_reference_args().
>
> - Update __acpi_node_get_property_reference() to call the (now updated)
>   acpi_fwnode_get_reference_args() passing NULL as nargs_prop to keep
>   the behavior of __acpi_node_get_property_reference() intact.
>
> Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>

LGTM now, so

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/property.c | 101 ++++++++++++++++++++--------------------
>  1 file changed, 50 insertions(+), 51 deletions(-)
>
> diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
> index 436019d96027..d4863746fb11 100644
> --- a/drivers/acpi/property.c
> +++ b/drivers/acpi/property.c
> @@ -882,45 +882,10 @@ static struct fwnode_handle *acpi_parse_string_ref(const struct fwnode_handle *f
>         return &dn->fwnode;
>  }
>
> -/**
> - * __acpi_node_get_property_reference - returns handle to the referenced object
> - * @fwnode: Firmware node to get the property from
> - * @propname: Name of the property
> - * @index: Index of the reference to return
> - * @num_args: Maximum number of arguments after each reference
> - * @args: Location to store the returned reference with optional arguments
> - *       (may be NULL)
> - *
> - * Find property with @name, verifify that it is a package containing at least
> - * one object reference and if so, store the ACPI device object pointer to the
> - * target object in @args->adev.  If the reference includes arguments, store
> - * them in the @args->args[] array.
> - *
> - * If there's more than one reference in the property value package, @index is
> - * used to select the one to return.
> - *
> - * It is possible to leave holes in the property value set like in the
> - * example below:
> - *
> - * Package () {
> - *     "cs-gpios",
> - *     Package () {
> - *        ^GPIO, 19, 0, 0,
> - *        ^GPIO, 20, 0, 0,
> - *        0,
> - *        ^GPIO, 21, 0, 0,
> - *     }
> - * }
> - *
> - * Calling this function with index %2 or index %3 return %-ENOENT. If the
> - * property does not contain any more values %-ENOENT is returned. The NULL
> - * entry must be single integer and preferably contain value %0.
> - *
> - * Return: %0 on success, negative error code on failure.
> - */
> -int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
> -       const char *propname, size_t index, size_t num_args,
> -       struct fwnode_reference_args *args)
> +static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
> +                                         const char *propname, const char *nargs_prop,
> +                                         unsigned int args_count, unsigned int index,
> +                                         struct fwnode_reference_args *args)
>  {
>         const union acpi_object *element, *end;
>         const union acpi_object *obj;
> @@ -999,7 +964,7 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
>
>                         ret = acpi_get_ref_args(idx == index ? args : NULL,
>                                                 acpi_fwnode_handle(device),
> -                                               &element, end, num_args);
> +                                               &element, end, args_count);
>                         if (ret < 0)
>                                 return ret;
>
> @@ -1017,7 +982,7 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
>
>                         ret = acpi_get_ref_args(idx == index ? args : NULL,
>                                                 ref_fwnode, &element, end,
> -                                               num_args);
> +                                               args_count);
>                         if (ret < 0)
>                                 return ret;
>
> @@ -1039,6 +1004,50 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
>
>         return -ENOENT;
>  }
> +
> +/**
> + * __acpi_node_get_property_reference - returns handle to the referenced object
> + * @fwnode: Firmware node to get the property from
> + * @propname: Name of the property
> + * @index: Index of the reference to return
> + * @num_args: Maximum number of arguments after each reference
> + * @args: Location to store the returned reference with optional arguments
> + *       (may be NULL)
> + *
> + * Find property with @name, verifify that it is a package containing at least
> + * one object reference and if so, store the ACPI device object pointer to the
> + * target object in @args->adev.  If the reference includes arguments, store
> + * them in the @args->args[] array.
> + *
> + * If there's more than one reference in the property value package, @index is
> + * used to select the one to return.
> + *
> + * It is possible to leave holes in the property value set like in the
> + * example below:
> + *
> + * Package () {
> + *     "cs-gpios",
> + *     Package () {
> + *        ^GPIO, 19, 0, 0,
> + *        ^GPIO, 20, 0, 0,
> + *        0,
> + *        ^GPIO, 21, 0, 0,
> + *     }
> + * }
> + *
> + * Calling this function with index %2 or index %3 return %-ENOENT. If the
> + * property does not contain any more values %-ENOENT is returned. The NULL
> + * entry must be single integer and preferably contain value %0.
> + *
> + * Return: %0 on success, negative error code on failure.
> + */
> +int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
> +                                      const char *propname, size_t index,
> +                                      size_t num_args,
> +                                      struct fwnode_reference_args *args)
> +{
> +       return acpi_fwnode_get_reference_args(fwnode, propname, NULL, index, num_args, args);
> +}
>  EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
>
>  static int acpi_data_prop_read_single(const struct acpi_device_data *data,
> @@ -1558,16 +1567,6 @@ acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
>                                    val, nval);
>  }
>
> -static int
> -acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
> -                              const char *prop, const char *nargs_prop,
> -                              unsigned int args_count, unsigned int index,
> -                              struct fwnode_reference_args *args)
> -{
> -       return __acpi_node_get_property_reference(fwnode, prop, index,
> -                                                 args_count, args);
> -}
> -
>  static const char *acpi_fwnode_get_name(const struct fwnode_handle *fwnode)
>  {
>         const struct acpi_device *adev;
> --
> 2.43.0
>

Re: [PATCH v8 15/24] ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()

[Rafael J. Wysocki]

On Fri, Jul 4, 2025 at 9:07 AM Anup Patel <apatel@ventanamicro.com> wrote:
>
> From: Sunil V L <sunilvl@ventanamicro.com>
>
> Currently, ACPI does not support the use of a nargs_prop (e.g.,
> associated with a reference in fwnode_property_get_reference_args().
> Instead, ACPI expects the number of arguments (nargs) to be explicitly
> passed or known.
>
> This behavior diverges from Open Firmware (OF), which allows the use of
> a #*-cells property in the referenced node to determine the number of
> arguments. Since fwnode_property_get_reference_args() is a common
> interface used across both OF and ACPI firmware paradigms, it is
> desirable to have a unified calling convention that works seamlessly for
> both.
>
> Add the support for ACPI to parse a nargs_prop from the referenced
> fwnode, aligning its behavior with the OF backend. This allows drivers
> and subsystems using fwnode_property_get_reference_args() to work in a
> firmware-agnostic way without having to hardcode or special-case
> argument counts for ACPI.
>
> Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>

LGTM now, so

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/property.c | 29 +++++++++++++++++++++++++----
>  drivers/base/property.c |  2 +-
>  2 files changed, 26 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
> index d4863746fb11..e92402deee77 100644
> --- a/drivers/acpi/property.c
> +++ b/drivers/acpi/property.c
> @@ -804,13 +804,35 @@ acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
>         return NULL;
>  }
>
> +static unsigned int acpi_fwnode_get_args_count(struct fwnode_handle *fwnode,
> +                                              const char *nargs_prop)
> +{
> +       const struct acpi_device_data *data;
> +       const union acpi_object *obj;
> +       int ret;
> +
> +       data = acpi_device_data_of_node(fwnode);
> +       if (!data)
> +               return 0;
> +
> +       ret = acpi_data_get_property(data, nargs_prop, ACPI_TYPE_INTEGER, &obj);
> +       if (ret)
> +               return 0;
> +
> +       return obj->integer.value;
> +}
> +
>  static int acpi_get_ref_args(struct fwnode_reference_args *args,
>                              struct fwnode_handle *ref_fwnode,
> +                            const char *nargs_prop,
>                              const union acpi_object **element,
>                              const union acpi_object *end, size_t num_args)
>  {
>         u32 nargs = 0, i;
>
> +       if (nargs_prop)
> +               num_args = acpi_fwnode_get_args_count(ref_fwnode, nargs_prop);
> +
>         /*
>          * Assume the following integer elements are all args. Stop counting on
>          * the first reference (possibly represented as a string) or end of the
> @@ -961,10 +983,10 @@ static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
>                                 return -EINVAL;
>
>                         element++;
> -
>                         ret = acpi_get_ref_args(idx == index ? args : NULL,
>                                                 acpi_fwnode_handle(device),
> -                                               &element, end, args_count);
> +                                               nargs_prop, &element, end,
> +                                               args_count);
>                         if (ret < 0)
>                                 return ret;
>
> @@ -979,9 +1001,8 @@ static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
>                                 return -EINVAL;
>
>                         element++;
> -
>                         ret = acpi_get_ref_args(idx == index ? args : NULL,
> -                                               ref_fwnode, &element, end,
> +                                               ref_fwnode, nargs_prop, &element, end,
>                                                 args_count);
>                         if (ret < 0)
>                                 return ret;
> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index f626d5bbe806..6a63860579dd 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -578,7 +578,7 @@ EXPORT_SYMBOL_GPL(fwnode_property_match_property_string);
>   * @prop:      The name of the property
>   * @nargs_prop:        The name of the property telling the number of
>   *             arguments in the referred node. NULL if @nargs is known,
> - *             otherwise @nargs is ignored. Only relevant on OF.
> + *             otherwise @nargs is ignored.
>   * @nargs:     Number of arguments. Ignored if @nargs_prop is non-NULL.
>   * @index:     Index of the reference, from zero onwards.
>   * @args:      Result structure with reference and integer arguments.
> --
> 2.43.0
>

Re: [PATCH v8 14/24] ACPI: property: Refactor acpi_fwnode_get_reference_args() to support nargs_prop

[Andy Shevchenko]

On Fri, Jul 04, 2025 at 12:33:46PM +0530, Anup Patel wrote:
> 
> Currently, acpi_fwnode_get_reference_args() delegates to the internal
> function __acpi_node_get_property_reference() to retrieve property
> references. However, this function does not handle the nargs_prop (cells
> property) parameter, and instead expects the number of arguments (nargs)
> to be known or hardcoded.
> 
> As a result, when fwnode_property_get_reference_args() is used with a
> valid nargs_prop, the ACPI backend ignores it, whereas the Device Tree
> (DT) backend uses the #*-cells property from the reference node to
> determine the number of arguments dynamically.
> 
> To support the nargs_prop in ACPI, refactor the code as follows:
> 
> - Move the implementation from __acpi_node_get_property_reference()
>   into acpi_fwnode_get_reference_args().
> 
> - Update __acpi_node_get_property_reference() to call the (now updated)
>   acpi_fwnode_get_reference_args() passing NULL as nargs_prop to keep
>   the behavior of __acpi_node_get_property_reference() intact.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v8 15/24] ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()

[Andy Shevchenko]

On Fri, Jul 04, 2025 at 12:33:47PM +0530, Anup Patel wrote:
> 
> Currently, ACPI does not support the use of a nargs_prop (e.g.,
> associated with a reference in fwnode_property_get_reference_args().
> Instead, ACPI expects the number of arguments (nargs) to be explicitly
> passed or known.
> 
> This behavior diverges from Open Firmware (OF), which allows the use of
> a #*-cells property in the referenced node to determine the number of
> arguments. Since fwnode_property_get_reference_args() is a common
> interface used across both OF and ACPI firmware paradigms, it is
> desirable to have a unified calling convention that works seamlessly for
> both.
> 
> Add the support for ACPI to parse a nargs_prop from the referenced
> fwnode, aligning its behavior with the OF backend. This allows drivers
> and subsystems using fwnode_property_get_reference_args() to work in a
> firmware-agnostic way without having to hardcode or special-case
> argument counts for ACPI.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Alexandre Ghiti]

Hi Anup,

On 7/4/25 09:03, Anup Patel wrote:
> The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> are frozen and finished public review at the RISC-V International.
>
> Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> and RPMI system MSI driver This series also includes ACPI support
> for SBI MPXY mailbox controller and RPMI system MSI drivers.
>
> These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> at: https://github.com/avpatel/linux.git
>
> To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> machine with OpenSBI and QEMU from the dev-upstream branch at:
> https://github.com/ventanamicro/opensbi.git
> https://github.com/ventanamicro/qemu.git
>
> [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
>
> Changes since v7:
>   - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21
>
> Changes since v6:
>   - Rebased the series on Linux-6.16-rc4
>   - Added Stephen's Reviewed-by in appropriate patches
>   - Addressed Andy's comments on PATCH5, PATCH6, PATCH9, and PATCH14
>   - New PATCH6 in this series which is factored-out from PATCH7
>
> Changes since v5:
>   - Rebased the series on Linux-6.16-rc2
>   - Added Conor's Reviewed-by in all DT binding patches
>   - Addressed Andy's comments on PATCH5
>   - Addressed Tglx's comments on PATCH12 and PATCH21
>
> Changes since v4:
>   - Rebased the series on Linux-6.16-rc1
>   - Dropped PATCH1 since a similar change is already merged
>     https://lore.kernel.org/linux-riscv/20250523101932.1594077-4-cleger@rivosinc.com/
>   - Addressed Andy's comments on PATCH4, PATCH5, PATCH6, PATCH7,
>     PATCH13, and PATCH17
>   - Addressed Atish's comments on PATCH11 and PATCH12
>   - Addressed Conor's comments on PATCH9
>
> Changes since v3:
>   - Rebased the series on Linux-6.15-rc7
>   - Updated PATCH2 DT bindings as-per Rob's suggestion
>   - Improved request_threaded_irq() usage in PATCH7
>   - Updated PATCH10 clk-rpmi driver as-per commments from Andy
>   - Updated PATCH13 irq-riscv-rpmi-sysmsi driver as-per comments
>     from Andy and Tglx
>   - Addressed ACPI related comments in PATCH14, PATCH15, PATCH18,
>     PATCH20 and PATCH21
>
> Changes since v2:
>   - Dropped the "RFC" tag from series since the SBI v3.0 and
>     RPMI v1.0 specifications are now frozen
>   - Rebased the series on Linux-6.15-rc5
>   - Split PATCH8 of v2 into two patches adding separate DT
>     bindings for "riscv,rpmi-mpxy-clock" and "riscv,rpmi-clock"
>   - Split PATCH10 of v2 into two patches adding separate DT
>     bindings for "riscv,rpmi-mpxy-system-msi" and
>     "riscv,rpmi-system-msi"
>   - Addressed comments from TGLX on PATCH11 of v2 adding irqchip
>     driver for RPMI system MSI
>   - Addressed ACPI related comments in PATCH15 and PATCH16 of v2
>   - New PATCH17 and PATCH18 in this series
>
> Changes since v1:
>   - Addressed DT bindings related comments in PATCH2, PATCH3, and
>     PATCH7 of v1 series
>   - Addressed comments in PATCH6 and PATCH8 of v1 series
>   - New PATCH6 in v2 series to allow fwnode based mailbox channel
>     request
>   - New PATCH10 and PATCH11 to add RPMI system MSI based interrupt
>     controller driver
>   - New PATCH12 to PATCH16 which adds ACPI support in SBI MPXY
>     mailbox driver and RPMI system MSI driver
>   - New PATCH17 to enable required kconfig option to allow graceful
>     shutdown on QEMU virt machine
>
> Anup Patel (14):
>    dt-bindings: mailbox: Add bindings for RPMI shared memory transport
>    dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension
>    RISC-V: Add defines for the SBI message proxy extension
>    mailbox: Add common header for RPMI messages sent via mailbox
>    mailbox: Allow controller specific mapping using fwnode
>    byteorder: Add memcpy_to_le32() and memcpy_from_le32()
>    mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver
>    dt-bindings: clock: Add RPMI clock service message proxy bindings
>    dt-bindings: clock: Add RPMI clock service controller bindings
>    dt-bindings: Add RPMI system MSI message proxy bindings
>    dt-bindings: Add RPMI system MSI interrupt controller bindings
>    irqchip: Add driver for the RPMI system MSI service group
>    RISC-V: Enable GPIO keyboard and event device in RV64 defconfig
>    MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers
>
> Rahul Pathak (1):
>    clk: Add clock driver for the RISC-V RPMI clock service group
>
> Sunil V L (9):
>    ACPI: property: Refactor acpi_fwnode_get_reference_args() to support
>      nargs_prop
>    ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()
>    ACPI: scan: Update honor list for RPMI System MSI
>    ACPI: RISC-V: Create interrupt controller list in sorted order
>    ACPI: RISC-V: Add support to update gsi range
>    ACPI: RISC-V: Add RPMI System MSI to GSI mapping
>    irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()
>    mailbox/riscv-sbi-mpxy: Add ACPI support
>    irqchip/riscv-rpmi-sysmsi: Add ACPI support
>
>   .../bindings/clock/riscv,rpmi-clock.yaml      |   64 ++
>   .../bindings/clock/riscv,rpmi-mpxy-clock.yaml |   64 ++
>   .../riscv,rpmi-mpxy-system-msi.yaml           |   67 ++
>   .../riscv,rpmi-system-msi.yaml                |   74 ++
>   .../mailbox/riscv,rpmi-shmem-mbox.yaml        |  124 ++
>   .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml |   51 +
>   MAINTAINERS                                   |   15 +
>   arch/riscv/configs/defconfig                  |    2 +
>   arch/riscv/include/asm/irq.h                  |    6 +
>   arch/riscv/include/asm/sbi.h                  |   63 +
>   drivers/acpi/property.c                       |  128 ++-
>   drivers/acpi/riscv/irq.c                      |   75 +-
>   drivers/acpi/scan.c                           |    2 +
>   drivers/base/property.c                       |    2 +-
>   drivers/clk/Kconfig                           |    8 +
>   drivers/clk/Makefile                          |    1 +
>   drivers/clk/clk-rpmi.c                        |  616 ++++++++++
>   drivers/irqchip/Kconfig                       |    7 +
>   drivers/irqchip/Makefile                      |    1 +
>   drivers/irqchip/irq-riscv-imsic-early.c       |    2 +
>   drivers/irqchip/irq-riscv-rpmi-sysmsi.c       |  328 ++++++
>   drivers/mailbox/Kconfig                       |   11 +
>   drivers/mailbox/Makefile                      |    2 +
>   drivers/mailbox/mailbox.c                     |   65 +-
>   drivers/mailbox/riscv-sbi-mpxy-mbox.c         | 1017 +++++++++++++++++
>   include/linux/byteorder/generic.h             |   16 +
>   include/linux/mailbox/riscv-rpmi-message.h    |  243 ++++
>   include/linux/mailbox_controller.h            |    3 +
>   include/linux/wordpart.h                      |   16 +
>   29 files changed, 2990 insertions(+), 83 deletions(-)
>   create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
>   create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
>   create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
>   create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
>   create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
>   create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
>   create mode 100644 drivers/clk/clk-rpmi.c
>   create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c
>   create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c
>   create mode 100644 include/linux/mailbox/riscv-rpmi-message.h
>

Most of the patches have been AB/RB by their respective maintainers, so 
how do you expect the patchset to be merged? Should it go through the 
riscv tree?

Let me know how you want to proceed, I'd be happy to merge it if that's 
easier for everyone.

Thanks,

Alex

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Anup Patel]

On Wed, Jul 16, 2025 at 6:52 PM Alexandre Ghiti <alex@ghiti.fr> wrote:
>
> Hi Anup,
>
> On 7/4/25 09:03, Anup Patel wrote:
> > The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> > are frozen and finished public review at the RISC-V International.
> >
> > Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> > Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> > and RPMI system MSI driver This series also includes ACPI support
> > for SBI MPXY mailbox controller and RPMI system MSI drivers.
> >
> > These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> > at: https://github.com/avpatel/linux.git
> >
> > To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> > machine with OpenSBI and QEMU from the dev-upstream branch at:
> > https://github.com/ventanamicro/opensbi.git
> > https://github.com/ventanamicro/qemu.git
> >
> > [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> > [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
> >
> > Changes since v7:
> >   - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21
> >
> > Changes since v6:
> >   - Rebased the series on Linux-6.16-rc4
> >   - Added Stephen's Reviewed-by in appropriate patches
> >   - Addressed Andy's comments on PATCH5, PATCH6, PATCH9, and PATCH14
> >   - New PATCH6 in this series which is factored-out from PATCH7
> >
> > Changes since v5:
> >   - Rebased the series on Linux-6.16-rc2
> >   - Added Conor's Reviewed-by in all DT binding patches
> >   - Addressed Andy's comments on PATCH5
> >   - Addressed Tglx's comments on PATCH12 and PATCH21
> >
> > Changes since v4:
> >   - Rebased the series on Linux-6.16-rc1
> >   - Dropped PATCH1 since a similar change is already merged
> >     https://lore.kernel.org/linux-riscv/20250523101932.1594077-4-cleger@rivosinc.com/
> >   - Addressed Andy's comments on PATCH4, PATCH5, PATCH6, PATCH7,
> >     PATCH13, and PATCH17
> >   - Addressed Atish's comments on PATCH11 and PATCH12
> >   - Addressed Conor's comments on PATCH9
> >
> > Changes since v3:
> >   - Rebased the series on Linux-6.15-rc7
> >   - Updated PATCH2 DT bindings as-per Rob's suggestion
> >   - Improved request_threaded_irq() usage in PATCH7
> >   - Updated PATCH10 clk-rpmi driver as-per commments from Andy
> >   - Updated PATCH13 irq-riscv-rpmi-sysmsi driver as-per comments
> >     from Andy and Tglx
> >   - Addressed ACPI related comments in PATCH14, PATCH15, PATCH18,
> >     PATCH20 and PATCH21
> >
> > Changes since v2:
> >   - Dropped the "RFC" tag from series since the SBI v3.0 and
> >     RPMI v1.0 specifications are now frozen
> >   - Rebased the series on Linux-6.15-rc5
> >   - Split PATCH8 of v2 into two patches adding separate DT
> >     bindings for "riscv,rpmi-mpxy-clock" and "riscv,rpmi-clock"
> >   - Split PATCH10 of v2 into two patches adding separate DT
> >     bindings for "riscv,rpmi-mpxy-system-msi" and
> >     "riscv,rpmi-system-msi"
> >   - Addressed comments from TGLX on PATCH11 of v2 adding irqchip
> >     driver for RPMI system MSI
> >   - Addressed ACPI related comments in PATCH15 and PATCH16 of v2
> >   - New PATCH17 and PATCH18 in this series
> >
> > Changes since v1:
> >   - Addressed DT bindings related comments in PATCH2, PATCH3, and
> >     PATCH7 of v1 series
> >   - Addressed comments in PATCH6 and PATCH8 of v1 series
> >   - New PATCH6 in v2 series to allow fwnode based mailbox channel
> >     request
> >   - New PATCH10 and PATCH11 to add RPMI system MSI based interrupt
> >     controller driver
> >   - New PATCH12 to PATCH16 which adds ACPI support in SBI MPXY
> >     mailbox driver and RPMI system MSI driver
> >   - New PATCH17 to enable required kconfig option to allow graceful
> >     shutdown on QEMU virt machine
> >
> > Anup Patel (14):
> >    dt-bindings: mailbox: Add bindings for RPMI shared memory transport
> >    dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension
> >    RISC-V: Add defines for the SBI message proxy extension
> >    mailbox: Add common header for RPMI messages sent via mailbox
> >    mailbox: Allow controller specific mapping using fwnode
> >    byteorder: Add memcpy_to_le32() and memcpy_from_le32()
> >    mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver
> >    dt-bindings: clock: Add RPMI clock service message proxy bindings
> >    dt-bindings: clock: Add RPMI clock service controller bindings
> >    dt-bindings: Add RPMI system MSI message proxy bindings
> >    dt-bindings: Add RPMI system MSI interrupt controller bindings
> >    irqchip: Add driver for the RPMI system MSI service group
> >    RISC-V: Enable GPIO keyboard and event device in RV64 defconfig
> >    MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers
> >
> > Rahul Pathak (1):
> >    clk: Add clock driver for the RISC-V RPMI clock service group
> >
> > Sunil V L (9):
> >    ACPI: property: Refactor acpi_fwnode_get_reference_args() to support
> >      nargs_prop
> >    ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()
> >    ACPI: scan: Update honor list for RPMI System MSI
> >    ACPI: RISC-V: Create interrupt controller list in sorted order
> >    ACPI: RISC-V: Add support to update gsi range
> >    ACPI: RISC-V: Add RPMI System MSI to GSI mapping
> >    irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()
> >    mailbox/riscv-sbi-mpxy: Add ACPI support
> >    irqchip/riscv-rpmi-sysmsi: Add ACPI support
> >
> >   .../bindings/clock/riscv,rpmi-clock.yaml      |   64 ++
> >   .../bindings/clock/riscv,rpmi-mpxy-clock.yaml |   64 ++
> >   .../riscv,rpmi-mpxy-system-msi.yaml           |   67 ++
> >   .../riscv,rpmi-system-msi.yaml                |   74 ++
> >   .../mailbox/riscv,rpmi-shmem-mbox.yaml        |  124 ++
> >   .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml |   51 +
> >   MAINTAINERS                                   |   15 +
> >   arch/riscv/configs/defconfig                  |    2 +
> >   arch/riscv/include/asm/irq.h                  |    6 +
> >   arch/riscv/include/asm/sbi.h                  |   63 +
> >   drivers/acpi/property.c                       |  128 ++-
> >   drivers/acpi/riscv/irq.c                      |   75 +-
> >   drivers/acpi/scan.c                           |    2 +
> >   drivers/base/property.c                       |    2 +-
> >   drivers/clk/Kconfig                           |    8 +
> >   drivers/clk/Makefile                          |    1 +
> >   drivers/clk/clk-rpmi.c                        |  616 ++++++++++
> >   drivers/irqchip/Kconfig                       |    7 +
> >   drivers/irqchip/Makefile                      |    1 +
> >   drivers/irqchip/irq-riscv-imsic-early.c       |    2 +
> >   drivers/irqchip/irq-riscv-rpmi-sysmsi.c       |  328 ++++++
> >   drivers/mailbox/Kconfig                       |   11 +
> >   drivers/mailbox/Makefile                      |    2 +
> >   drivers/mailbox/mailbox.c                     |   65 +-
> >   drivers/mailbox/riscv-sbi-mpxy-mbox.c         | 1017 +++++++++++++++++
> >   include/linux/byteorder/generic.h             |   16 +
> >   include/linux/mailbox/riscv-rpmi-message.h    |  243 ++++
> >   include/linux/mailbox_controller.h            |    3 +
> >   include/linux/wordpart.h                      |   16 +
> >   29 files changed, 2990 insertions(+), 83 deletions(-)
> >   create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
> >   create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
> >   create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
> >   create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
> >   create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
> >   create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
> >   create mode 100644 drivers/clk/clk-rpmi.c
> >   create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c
> >   create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c
> >   create mode 100644 include/linux/mailbox/riscv-rpmi-message.h
> >
>
> Most of the patches have been AB/RB by their respective maintainers, so
> how do you expect the patchset to be merged? Should it go through the
> riscv tree?
>
> Let me know how you want to proceed, I'd be happy to merge it if that's
> easier for everyone.
>

We discussed this series in today's patchwork meeting and
Palmer has agreed to take this through the RISC-V tree. He
will also provide a shared tag for the benefit of other maintainers.

Please sync-up with Palmer whenever you can.

Thanks,
Anup

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Jassi Brar]

On Fri, Jul 4, 2025 at 2:04 AM Anup Patel <apatel@ventanamicro.com> wrote:
>
> The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> are frozen and finished public review at the RISC-V International.
>
> Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> and RPMI system MSI driver This series also includes ACPI support
> for SBI MPXY mailbox controller and RPMI system MSI drivers.
>
> These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> at: https://github.com/avpatel/linux.git
>
> To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> machine with OpenSBI and QEMU from the dev-upstream branch at:
> https://github.com/ventanamicro/opensbi.git
> https://github.com/ventanamicro/qemu.git
>
> [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
>
> Changes since v7:
>  - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21
>
> Changes since v6:
>  - Rebased the series on Linux-6.16-rc4
>  - Added Stephen's Reviewed-by in appropriate patches
>  - Addressed Andy's comments on PATCH5, PATCH6, PATCH9, and PATCH14
>  - New PATCH6 in this series which is factored-out from PATCH7
>
> Changes since v5:
>  - Rebased the series on Linux-6.16-rc2
>  - Added Conor's Reviewed-by in all DT binding patches
>  - Addressed Andy's comments on PATCH5
>  - Addressed Tglx's comments on PATCH12 and PATCH21
>
> Changes since v4:
>  - Rebased the series on Linux-6.16-rc1
>  - Dropped PATCH1 since a similar change is already merged
>    https://lore.kernel.org/linux-riscv/20250523101932.1594077-4-cleger@rivosinc.com/
>  - Addressed Andy's comments on PATCH4, PATCH5, PATCH6, PATCH7,
>    PATCH13, and PATCH17
>  - Addressed Atish's comments on PATCH11 and PATCH12
>  - Addressed Conor's comments on PATCH9
>
> Changes since v3:
>  - Rebased the series on Linux-6.15-rc7
>  - Updated PATCH2 DT bindings as-per Rob's suggestion
>  - Improved request_threaded_irq() usage in PATCH7
>  - Updated PATCH10 clk-rpmi driver as-per commments from Andy
>  - Updated PATCH13 irq-riscv-rpmi-sysmsi driver as-per comments
>    from Andy and Tglx
>  - Addressed ACPI related comments in PATCH14, PATCH15, PATCH18,
>    PATCH20 and PATCH21
>
> Changes since v2:
>  - Dropped the "RFC" tag from series since the SBI v3.0 and
>    RPMI v1.0 specifications are now frozen
>  - Rebased the series on Linux-6.15-rc5
>  - Split PATCH8 of v2 into two patches adding separate DT
>    bindings for "riscv,rpmi-mpxy-clock" and "riscv,rpmi-clock"
>  - Split PATCH10 of v2 into two patches adding separate DT
>    bindings for "riscv,rpmi-mpxy-system-msi" and
>    "riscv,rpmi-system-msi"
>  - Addressed comments from TGLX on PATCH11 of v2 adding irqchip
>    driver for RPMI system MSI
>  - Addressed ACPI related comments in PATCH15 and PATCH16 of v2
>  - New PATCH17 and PATCH18 in this series
>
> Changes since v1:
>  - Addressed DT bindings related comments in PATCH2, PATCH3, and
>    PATCH7 of v1 series
>  - Addressed comments in PATCH6 and PATCH8 of v1 series
>  - New PATCH6 in v2 series to allow fwnode based mailbox channel
>    request
>  - New PATCH10 and PATCH11 to add RPMI system MSI based interrupt
>    controller driver
>  - New PATCH12 to PATCH16 which adds ACPI support in SBI MPXY
>    mailbox driver and RPMI system MSI driver
>  - New PATCH17 to enable required kconfig option to allow graceful
>    shutdown on QEMU virt machine
>
> Anup Patel (14):
>   dt-bindings: mailbox: Add bindings for RPMI shared memory transport
>   dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension
>   RISC-V: Add defines for the SBI message proxy extension
>   mailbox: Add common header for RPMI messages sent via mailbox
>   mailbox: Allow controller specific mapping using fwnode
>   byteorder: Add memcpy_to_le32() and memcpy_from_le32()
>   mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver
>   dt-bindings: clock: Add RPMI clock service message proxy bindings
>   dt-bindings: clock: Add RPMI clock service controller bindings
>   dt-bindings: Add RPMI system MSI message proxy bindings
>   dt-bindings: Add RPMI system MSI interrupt controller bindings
>   irqchip: Add driver for the RPMI system MSI service group
>   RISC-V: Enable GPIO keyboard and event device in RV64 defconfig
>   MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers
>
> Rahul Pathak (1):
>   clk: Add clock driver for the RISC-V RPMI clock service group
>
> Sunil V L (9):
>   ACPI: property: Refactor acpi_fwnode_get_reference_args() to support
>     nargs_prop
>   ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()
>   ACPI: scan: Update honor list for RPMI System MSI
>   ACPI: RISC-V: Create interrupt controller list in sorted order
>   ACPI: RISC-V: Add support to update gsi range
>   ACPI: RISC-V: Add RPMI System MSI to GSI mapping
>   irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()
>   mailbox/riscv-sbi-mpxy: Add ACPI support
>   irqchip/riscv-rpmi-sysmsi: Add ACPI support
>
>  .../bindings/clock/riscv,rpmi-clock.yaml      |   64 ++
>  .../bindings/clock/riscv,rpmi-mpxy-clock.yaml |   64 ++
>  .../riscv,rpmi-mpxy-system-msi.yaml           |   67 ++
>  .../riscv,rpmi-system-msi.yaml                |   74 ++
>  .../mailbox/riscv,rpmi-shmem-mbox.yaml        |  124 ++
>  .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml |   51 +
>  MAINTAINERS                                   |   15 +
>  arch/riscv/configs/defconfig                  |    2 +
>  arch/riscv/include/asm/irq.h                  |    6 +
>  arch/riscv/include/asm/sbi.h                  |   63 +
>  drivers/acpi/property.c                       |  128 ++-
>  drivers/acpi/riscv/irq.c                      |   75 +-
>  drivers/acpi/scan.c                           |    2 +
>  drivers/base/property.c                       |    2 +-
>  drivers/clk/Kconfig                           |    8 +
>  drivers/clk/Makefile                          |    1 +
>  drivers/clk/clk-rpmi.c                        |  616 ++++++++++
>  drivers/irqchip/Kconfig                       |    7 +
>  drivers/irqchip/Makefile                      |    1 +
>  drivers/irqchip/irq-riscv-imsic-early.c       |    2 +
>  drivers/irqchip/irq-riscv-rpmi-sysmsi.c       |  328 ++++++
>  drivers/mailbox/Kconfig                       |   11 +
>  drivers/mailbox/Makefile                      |    2 +
>  drivers/mailbox/mailbox.c                     |   65 +-
>  drivers/mailbox/riscv-sbi-mpxy-mbox.c         | 1017 +++++++++++++++++
>  include/linux/byteorder/generic.h             |   16 +
>  include/linux/mailbox/riscv-rpmi-message.h    |  243 ++++
>  include/linux/mailbox_controller.h            |    3 +
>  include/linux/wordpart.h                      |   16 +
>  29 files changed, 2990 insertions(+), 83 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
>  create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
>  create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
>  create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
>  create mode 100644 drivers/clk/clk-rpmi.c
>  create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c
>  create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c
>  create mode 100644 include/linux/mailbox/riscv-rpmi-message.h
>
For the mailbox changes ...
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>

Re: [PATCH v8 00/24] Linux SBI MPXY and RPMI drivers

[Anup Patel]

On Mon, Jul 21, 2025 at 1:09 AM Jassi Brar <jassisinghbrar@gmail.com> wrote:
>
> On Fri, Jul 4, 2025 at 2:04 AM Anup Patel <apatel@ventanamicro.com> wrote:
> >
> > The SBI v3.0 (MPXY extension) [1] and RPMI v1.0 [2] specifications
> > are frozen and finished public review at the RISC-V International.
> >
> > Currently, most of the RPMI and MPXY drivers are in OpenSBI whereas
> > Linux only has SBI MPXY mailbox controller driver, RPMI clock driver
> > and RPMI system MSI driver This series also includes ACPI support
> > for SBI MPXY mailbox controller and RPMI system MSI drivers.
> >
> > These patches can be found in the riscv_sbi_mpxy_mailbox_v8 branch
> > at: https://github.com/avpatel/linux.git
> >
> > To test these patches, boot Linux on "virt,rpmi=on,aia=aplic-imsic"
> > machine with OpenSBI and QEMU from the dev-upstream branch at:
> > https://github.com/ventanamicro/opensbi.git
> > https://github.com/ventanamicro/qemu.git
> >
> > [1] https://github.com/riscv-non-isa/riscv-sbi-doc/releases
> > [2] https://github.com/riscv-non-isa/riscv-rpmi/releases
> >
> > Changes since v7:
> >  - Addressed comments on PATCH3, PATCH7, PATCH10, PATCH14, and PATCH21
> >
> > Changes since v6:
> >  - Rebased the series on Linux-6.16-rc4
> >  - Added Stephen's Reviewed-by in appropriate patches
> >  - Addressed Andy's comments on PATCH5, PATCH6, PATCH9, and PATCH14
> >  - New PATCH6 in this series which is factored-out from PATCH7
> >
> > Changes since v5:
> >  - Rebased the series on Linux-6.16-rc2
> >  - Added Conor's Reviewed-by in all DT binding patches
> >  - Addressed Andy's comments on PATCH5
> >  - Addressed Tglx's comments on PATCH12 and PATCH21
> >
> > Changes since v4:
> >  - Rebased the series on Linux-6.16-rc1
> >  - Dropped PATCH1 since a similar change is already merged
> >    https://lore.kernel.org/linux-riscv/20250523101932.1594077-4-cleger@rivosinc.com/
> >  - Addressed Andy's comments on PATCH4, PATCH5, PATCH6, PATCH7,
> >    PATCH13, and PATCH17
> >  - Addressed Atish's comments on PATCH11 and PATCH12
> >  - Addressed Conor's comments on PATCH9
> >
> > Changes since v3:
> >  - Rebased the series on Linux-6.15-rc7
> >  - Updated PATCH2 DT bindings as-per Rob's suggestion
> >  - Improved request_threaded_irq() usage in PATCH7
> >  - Updated PATCH10 clk-rpmi driver as-per commments from Andy
> >  - Updated PATCH13 irq-riscv-rpmi-sysmsi driver as-per comments
> >    from Andy and Tglx
> >  - Addressed ACPI related comments in PATCH14, PATCH15, PATCH18,
> >    PATCH20 and PATCH21
> >
> > Changes since v2:
> >  - Dropped the "RFC" tag from series since the SBI v3.0 and
> >    RPMI v1.0 specifications are now frozen
> >  - Rebased the series on Linux-6.15-rc5
> >  - Split PATCH8 of v2 into two patches adding separate DT
> >    bindings for "riscv,rpmi-mpxy-clock" and "riscv,rpmi-clock"
> >  - Split PATCH10 of v2 into two patches adding separate DT
> >    bindings for "riscv,rpmi-mpxy-system-msi" and
> >    "riscv,rpmi-system-msi"
> >  - Addressed comments from TGLX on PATCH11 of v2 adding irqchip
> >    driver for RPMI system MSI
> >  - Addressed ACPI related comments in PATCH15 and PATCH16 of v2
> >  - New PATCH17 and PATCH18 in this series
> >
> > Changes since v1:
> >  - Addressed DT bindings related comments in PATCH2, PATCH3, and
> >    PATCH7 of v1 series
> >  - Addressed comments in PATCH6 and PATCH8 of v1 series
> >  - New PATCH6 in v2 series to allow fwnode based mailbox channel
> >    request
> >  - New PATCH10 and PATCH11 to add RPMI system MSI based interrupt
> >    controller driver
> >  - New PATCH12 to PATCH16 which adds ACPI support in SBI MPXY
> >    mailbox driver and RPMI system MSI driver
> >  - New PATCH17 to enable required kconfig option to allow graceful
> >    shutdown on QEMU virt machine
> >
> > Anup Patel (14):
> >   dt-bindings: mailbox: Add bindings for RPMI shared memory transport
> >   dt-bindings: mailbox: Add bindings for RISC-V SBI MPXY extension
> >   RISC-V: Add defines for the SBI message proxy extension
> >   mailbox: Add common header for RPMI messages sent via mailbox
> >   mailbox: Allow controller specific mapping using fwnode
> >   byteorder: Add memcpy_to_le32() and memcpy_from_le32()
> >   mailbox: Add RISC-V SBI message proxy (MPXY) based mailbox driver
> >   dt-bindings: clock: Add RPMI clock service message proxy bindings
> >   dt-bindings: clock: Add RPMI clock service controller bindings
> >   dt-bindings: Add RPMI system MSI message proxy bindings
> >   dt-bindings: Add RPMI system MSI interrupt controller bindings
> >   irqchip: Add driver for the RPMI system MSI service group
> >   RISC-V: Enable GPIO keyboard and event device in RV64 defconfig
> >   MAINTAINERS: Add entry for RISC-V RPMI and MPXY drivers
> >
> > Rahul Pathak (1):
> >   clk: Add clock driver for the RISC-V RPMI clock service group
> >
> > Sunil V L (9):
> >   ACPI: property: Refactor acpi_fwnode_get_reference_args() to support
> >     nargs_prop
> >   ACPI: Add support for nargs_prop in acpi_fwnode_get_reference_args()
> >   ACPI: scan: Update honor list for RPMI System MSI
> >   ACPI: RISC-V: Create interrupt controller list in sorted order
> >   ACPI: RISC-V: Add support to update gsi range
> >   ACPI: RISC-V: Add RPMI System MSI to GSI mapping
> >   irqchip/irq-riscv-imsic-early: Export imsic_acpi_get_fwnode()
> >   mailbox/riscv-sbi-mpxy: Add ACPI support
> >   irqchip/riscv-rpmi-sysmsi: Add ACPI support
> >
> >  .../bindings/clock/riscv,rpmi-clock.yaml      |   64 ++
> >  .../bindings/clock/riscv,rpmi-mpxy-clock.yaml |   64 ++
> >  .../riscv,rpmi-mpxy-system-msi.yaml           |   67 ++
> >  .../riscv,rpmi-system-msi.yaml                |   74 ++
> >  .../mailbox/riscv,rpmi-shmem-mbox.yaml        |  124 ++
> >  .../bindings/mailbox/riscv,sbi-mpxy-mbox.yaml |   51 +
> >  MAINTAINERS                                   |   15 +
> >  arch/riscv/configs/defconfig                  |    2 +
> >  arch/riscv/include/asm/irq.h                  |    6 +
> >  arch/riscv/include/asm/sbi.h                  |   63 +
> >  drivers/acpi/property.c                       |  128 ++-
> >  drivers/acpi/riscv/irq.c                      |   75 +-
> >  drivers/acpi/scan.c                           |    2 +
> >  drivers/base/property.c                       |    2 +-
> >  drivers/clk/Kconfig                           |    8 +
> >  drivers/clk/Makefile                          |    1 +
> >  drivers/clk/clk-rpmi.c                        |  616 ++++++++++
> >  drivers/irqchip/Kconfig                       |    7 +
> >  drivers/irqchip/Makefile                      |    1 +
> >  drivers/irqchip/irq-riscv-imsic-early.c       |    2 +
> >  drivers/irqchip/irq-riscv-rpmi-sysmsi.c       |  328 ++++++
> >  drivers/mailbox/Kconfig                       |   11 +
> >  drivers/mailbox/Makefile                      |    2 +
> >  drivers/mailbox/mailbox.c                     |   65 +-
> >  drivers/mailbox/riscv-sbi-mpxy-mbox.c         | 1017 +++++++++++++++++
> >  include/linux/byteorder/generic.h             |   16 +
> >  include/linux/mailbox/riscv-rpmi-message.h    |  243 ++++
> >  include/linux/mailbox_controller.h            |    3 +
> >  include/linux/wordpart.h                      |   16 +
> >  29 files changed, 2990 insertions(+), 83 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-clock.yaml
> >  create mode 100644 Documentation/devicetree/bindings/clock/riscv,rpmi-mpxy-clock.yaml
> >  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-mpxy-system-msi.yaml
> >  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,rpmi-system-msi.yaml
> >  create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,rpmi-shmem-mbox.yaml
> >  create mode 100644 Documentation/devicetree/bindings/mailbox/riscv,sbi-mpxy-mbox.yaml
> >  create mode 100644 drivers/clk/clk-rpmi.c
> >  create mode 100644 drivers/irqchip/irq-riscv-rpmi-sysmsi.c
> >  create mode 100644 drivers/mailbox/riscv-sbi-mpxy-mbox.c
> >  create mode 100644 include/linux/mailbox/riscv-rpmi-message.h
> >
> For the mailbox changes ...
> Acked-by: Jassi Brar <jassisinghbrar@gmail.com>

Thanks Jassi !

--Anup

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Stephen Boyd]

Quoting Anup Patel (2025-07-04 00:03:40)
> Add device tree bindings for the RPMI clock service group based
> message proxy implemented by the SBI implementation (machine mode
> firmware or hypervisor).
> 
> The RPMI clock service group is defined by the RISC-V platform
> management interface (RPMI) specification.
> 
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
[...]
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    clock-controller {

Maybe the name should be 'clock-service' then? I don't understand SBI so
not sure why this is in DT to begin with. Is something consuming this
node? Or a driver is binding to it?

> +        compatible = "riscv,rpmi-mpxy-clock";
> +        mboxes = <&rpmi_shmem_mbox 0x8>;
> +        riscv,sbi-mpxy-channel-id = <0x1000>;
> +    };

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Anup Patel]

On Fri, Jul 25, 2025 at 8:12 AM Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Anup Patel (2025-07-04 00:03:40)
> > Add device tree bindings for the RPMI clock service group based
> > message proxy implemented by the SBI implementation (machine mode
> > firmware or hypervisor).
> >
> > The RPMI clock service group is defined by the RISC-V platform
> > management interface (RPMI) specification.
> >
> > Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> [...]
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    clock-controller {
>
> Maybe the name should be 'clock-service' then? I don't understand SBI so
> not sure why this is in DT to begin with. Is something consuming this
> node? Or a driver is binding to it?

SBI is a syscall style interface between SBI implementation (aka
M-mode firmware or hypervisor) and supervisor software (aka
Linux kernel).

We have DT based drivers in OpenSBI (M-mode firmware). This
binding allows Clock message proxy driver to be probed on the
OpenSBI side. The clock message proxy driver allows Linux
RPMI clock driver to send RPMI messages via OpenSBI as
proxy thereby sharing the RPMI transport between OpenSBI
and Linux kernel.

Regards,
Anup

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Stephen Boyd]

Quoting Anup Patel (2025-07-25 09:16:12)
> On Fri, Jul 25, 2025 at 8:12 AM Stephen Boyd <sboyd@kernel.org> wrote:
> >
> > Quoting Anup Patel (2025-07-04 00:03:40)
> > > Add device tree bindings for the RPMI clock service group based
> > > message proxy implemented by the SBI implementation (machine mode
> > > firmware or hypervisor).
> > >
> > > The RPMI clock service group is defined by the RISC-V platform
> > > management interface (RPMI) specification.
> > >
> > > Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> > > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > [...]
> > > +additionalProperties: false
> > > +
> > > +examples:
> > > +  - |
> > > +    clock-controller {
> >
> > Maybe the name should be 'clock-service' then? I don't understand SBI so
> > not sure why this is in DT to begin with. Is something consuming this
> > node? Or a driver is binding to it?
> 
> SBI is a syscall style interface between SBI implementation (aka
> M-mode firmware or hypervisor) and supervisor software (aka
> Linux kernel).
> 
> We have DT based drivers in OpenSBI (M-mode firmware). This
> binding allows Clock message proxy driver to be probed on the
> OpenSBI side. The clock message proxy driver allows Linux
> RPMI clock driver to send RPMI messages via OpenSBI as
> proxy thereby sharing the RPMI transport between OpenSBI
> and Linux kernel.

Let me try to clarify my confusion. A 'clock-controller' node without a
'#clock-cells' property is confusing.

It's not providing clks? The SBI firmware is not discoverable? Do you
have a pointer to the DTS for this node and the clock controller node in
the next patch? I'd like to understand why this is named a clock
controller when it doesn't provide clks.

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Anup Patel]

On Sun, Jul 27, 2025 at 11:53 AM Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Anup Patel (2025-07-25 09:16:12)
> > On Fri, Jul 25, 2025 at 8:12 AM Stephen Boyd <sboyd@kernel.org> wrote:
> > >
> > > Quoting Anup Patel (2025-07-04 00:03:40)
> > > > Add device tree bindings for the RPMI clock service group based
> > > > message proxy implemented by the SBI implementation (machine mode
> > > > firmware or hypervisor).
> > > >
> > > > The RPMI clock service group is defined by the RISC-V platform
> > > > management interface (RPMI) specification.
> > > >
> > > > Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> > > > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > > [...]
> > > > +additionalProperties: false
> > > > +
> > > > +examples:
> > > > +  - |
> > > > +    clock-controller {
> > >
> > > Maybe the name should be 'clock-service' then? I don't understand SBI so
> > > not sure why this is in DT to begin with. Is something consuming this
> > > node? Or a driver is binding to it?
> >
> > SBI is a syscall style interface between SBI implementation (aka
> > M-mode firmware or hypervisor) and supervisor software (aka
> > Linux kernel).
> >
> > We have DT based drivers in OpenSBI (M-mode firmware). This
> > binding allows Clock message proxy driver to be probed on the
> > OpenSBI side. The clock message proxy driver allows Linux
> > RPMI clock driver to send RPMI messages via OpenSBI as
> > proxy thereby sharing the RPMI transport between OpenSBI
> > and Linux kernel.
>
> Let me try to clarify my confusion. A 'clock-controller' node without a
> '#clock-cells' property is confusing.

Ahh, I see your point. The node name need not be 'clock-controller'
since the node is for a firmware driver which provides MPXY channel
to supervisor software (aka Linux kernel).

>
> It's not providing clks? The SBI firmware is not discoverable? Do you
> have a pointer to the DTS for this node and the clock controller node in
> the next patch? I'd like to understand why this is named a clock
> controller when it doesn't provide clks.

The firmware driver is not providing clks. Also, the SBI firmware and
various SBI extensions are indeed discoverable from supervisor software.

On the Linux side, we have two DT nodes:
1) One DT node for the SBI MPXY based mailbox-controller
    (Refer, https://lore.kernel.org/all/20250704070356.1683992-3-apatel@ventanamicro.com/)
2) Second DT node for the clock-controller based on the
    RPMI clock service group.
    (Refer, https://lore.kernel.org/all/20250704070356.1683992-10-apatel@ventanamicro.com/)

Regards,
Anup

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Stephen Boyd]

Quoting Anup Patel (2025-07-28 02:19:23)
> On Sun, Jul 27, 2025 at 11:53 AM Stephen Boyd <sboyd@kernel.org> wrote:
> >
> > It's not providing clks? The SBI firmware is not discoverable? Do you
> > have a pointer to the DTS for this node and the clock controller node in
> > the next patch? I'd like to understand why this is named a clock
> > controller when it doesn't provide clks.
> 
> The firmware driver is not providing clks. Also, the SBI firmware and
> various SBI extensions are indeed discoverable from supervisor software.

If SBI extensions are discoverable from software why do we need a DT
binding?

Re: [PATCH v8 08/24] dt-bindings: clock: Add RPMI clock service message proxy bindings

[Anup Patel]

On Thu, Jul 31, 2025 at 10:20 PM Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Anup Patel (2025-07-28 02:19:23)
> > On Sun, Jul 27, 2025 at 11:53 AM Stephen Boyd <sboyd@kernel.org> wrote:
> > >
> > > It's not providing clks? The SBI firmware is not discoverable? Do you
> > > have a pointer to the DTS for this node and the clock controller node in
> > > the next patch? I'd like to understand why this is named a clock
> > > controller when it doesn't provide clks.
> >
> > The firmware driver is not providing clks. Also, the SBI firmware and
> > various SBI extensions are indeed discoverable from supervisor software.
>
> If SBI extensions are discoverable from software why do we need a DT
> binding?

The firmware which implements the SBI MPXY channel needs to
discover the underlying RPMI service group from DT.

Let's say we have only one RPMI shared memory transport between
application processors and platform microcontroller. This RPMI transport
will be shared between M-mode firmware (OpenSBI) and S-mode (Linux).

The OpenSBI will use the following example DT nodes to probe the
mailbox driver and MPXY driver to expose MPXY channel to S-mode.

mb: mailbox@10080000 {
    compatible = "riscv,rpmi-shmem-mbox";
    reg = <0x00 0x10080000 0x00 0x10000>,
         <0x00 0x10090000 0x00 0x10000>,
         <0x00 0x100a0000 0x00 0x10000>;
    reg-names = "a2p-req", "p2a-ack", "a2p-doorbell";
    #mbox-cells = <0x01>;
    riscv,slot-size = <0x40>;
    riscv,p2a-doorbell-sysmsi-index = <3>;
};

clock-service {
    compatible = "riscv,rpmi-mpxy-clock";
    mboxes = <&mb 0x08>;
    riscv,sbi-mpxy-channel-id = <0x1001>;
};

Based on the above, Linux will use the following example DT nodes
to probe the Linux MPXY mailbox driver and RPMI clock driver.

mpxy_mbox: sbi-mpxy-mbox {
    compatible = "riscv,sbi-mpxy-mbox";
    #mbox-cells = <2>;
    msi-parent = <&imsic_slevel>;
};

rpmi-clk {
    compatible = "riscv,rpmi-clock";
    #clock-cells = <1>;
    mboxes = <&mpxy_mbox 0x1001 0x0>;
};

I hope the above example DT node provides a better picture
about how DT bindings are used in firmware and Linux.

Regards,
Anup