[PATCH v4 0/7] Introduce SpacemiT K1 PCIe phy and host controller

[PATCH v4 0/7] Introduce SpacemiT K1 PCIe phy and host controller

[Alex Elder]

This series introduces a PHY driver and a PCIe driver to support PCIe
on the SpacemiT K1 SoC.  The PCIe implementation is derived from a
Synopsys DesignWare PCIe IP.  The PHY driver supports one combination
PCIe/USB PHY as well as two PCIe-only PHYs.  The combo PHY port uses
one PCIe lane, and the other two ports each have two lanes.  All PCIe
ports operate at 5 GT/second.

The PCIe PHYs must be configured using a value that can only be
determined using the combo PHY, operating in PCIe mode.  To allow
that PHY to be used for USB, the calibration step is performed by
the PHY driver automatically at probe time.  Once this step is done,
the PHY can be used for either PCIe or USB.

Version 3 of this series incorporates suggestions made during the
review of version 2, and based on some error reports from Aurelien
Jarno and Johannes Erdfelt, disabled ASPM L1.  Specific highlights
are detailed below.

					-Alex

This series is available here:
  https://github.com/riscstar/linux/tree/outgoing/pcie-v4

Between version 3 and version 4:
  - In the DT binding for the PCIe host controlloller, add a new
    sub-node representing the root port
  - Move the phys and supply properties out of the PCIe host controller
    and into the root port node
  - Define the spacemit,apmu property later in the binding and DTS files
  - Define the device_type property first in the binding examples and
    DTS files
  - Add root port sub-nodes in the examples and the DTS files
  - Select the PCI_PWRCTRL_SLOT config option when PCIE_SPACEMIT_K1 is
    enabled
  - Parse the root port node in the driver, and get the PHY
  - Leverage the PCI pwrctrl slot driver to get and enable the regulator
  - Don't set num_vectors to 256; just use the default (32)
  - Cleaned up some comments, white space, and symbol names based on
    feedback from Mani
  - Add some runtime PM calls to ensure it works propertly
  - Add a new post_init callback, which disables ASPM L1 for the link

Here is version 3 of this series:
  https://lore.kernel.org/lkml/20251017190740.306780-1-elder@riscstar.com/

Between version 2 and version 3:
  - Reviewed-by from Rob added to the first two patches
  - The "num-viewport" property has been removed
  - The "phy" reset is listed first in the combo PHY binding
  - The PHY now requires a resets property to specify the "phy" reset
  - The PCIe driver no longer requires a "phy" reset
  - The PHY driver now gets and deasserts the reset for all PHYs
  - Error handling and "put" of clocks in the PHY driver has been
    corrected (for clk_bulk_get() rather than clk_bulk_get_all())

Here is version 2 of this series:
  https://lore.kernel.org/lkml/20251013153526.2276556-1-elder@riscstar.com/

Full details of changes made for version 2 are available there.


Alex Elder (7):
  dt-bindings: phy: spacemit: add SpacemiT PCIe/combo PHY
  dt-bindings: phy: spacemit: introduce PCIe PHY
  dt-bindings: pci: spacemit: introduce PCIe host controller
  phy: spacemit: introduce PCIe/combo PHY
  PCI: spacemit: introduce SpacemiT PCIe host driver
  riscv: dts: spacemit: add a PCIe regulator
  riscv: dts: spacemit: PCIe and PHY-related updates

 .../bindings/pci/spacemit,k1-pcie-host.yaml   | 157 ++++
 .../bindings/phy/spacemit,k1-combo-phy.yaml   | 114 +++
 .../bindings/phy/spacemit,k1-pcie-phy.yaml    |  71 ++
 .../boot/dts/spacemit/k1-bananapi-f3.dts      |  44 ++
 arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi  |  33 +
 arch/riscv/boot/dts/spacemit/k1.dtsi          | 176 +++++
 drivers/pci/controller/dwc/Kconfig            |  11 +
 drivers/pci/controller/dwc/Makefile           |   1 +
 drivers/pci/controller/dwc/pcie-spacemit-k1.c | 349 +++++++++
 drivers/phy/Kconfig                           |  11 +
 drivers/phy/Makefile                          |   1 +
 drivers/phy/phy-spacemit-k1-pcie.c            | 670 ++++++++++++++++++
 12 files changed, 1638 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
 create mode 100644 Documentation/devicetree/bindings/phy/spacemit,k1-combo-phy.yaml
 create mode 100644 Documentation/devicetree/bindings/phy/spacemit,k1-pcie-phy.yaml
 create mode 100644 drivers/pci/controller/dwc/pcie-spacemit-k1.c
 create mode 100644 drivers/phy/phy-spacemit-k1-pcie.c


base-commit: 131f3d9446a6075192cdd91f197989d98302faa6
-- 
2.48.1

[PATCH v4 1/7] dt-bindings: phy: spacemit: add SpacemiT PCIe/combo PHY

[Alex Elder]

Add the Device Tree binding for the PCIe/USB 3.0 combo PHY found in
the SpacemiT K1 SoC.  This is one of three PCIe PHYs, and is unusual
in that only the combo PHY can perform a calibration step needed to
determine settings used by the other two PCIe PHYs.

Calibration must be done with the combo PHY in PCIe mode, and to allow
this to occur independent of the eventual use for the PHY (PCIe or USB)
some PCIe-related properties must be supplied: clocks; resets; and a
syscon phandle.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../bindings/phy/spacemit,k1-combo-phy.yaml   | 114 ++++++++++++++++++
 1 file changed, 114 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/spacemit,k1-combo-phy.yaml

diff --git a/Documentation/devicetree/bindings/phy/spacemit,k1-combo-phy.yaml b/Documentation/devicetree/bindings/phy/spacemit,k1-combo-phy.yaml
new file mode 100644
index 0000000000000..b59476cd78b57
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/spacemit,k1-combo-phy.yaml
@@ -0,0 +1,114 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/spacemit,k1-combo-phy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SpacemiT K1 PCIe/USB3 Combo PHY
+
+maintainers:
+  - Alex Elder <elder@riscstar.com>
+
+description: >
+  Of the three PHYs on the SpacemiT K1 SoC capable of being used for
+  PCIe, one is a combo PHY that can also be configured for use by a
+  USB 3 controller.  Using PCIe or USB 3 is a board design decision.
+
+  The combo PHY is also the only PCIe PHY that is able to determine
+  PCIe calibration values to use, and this must be determined before
+  the other two PCIe PHYs can be used.  This calibration must be
+  performed with the combo PHY in PCIe mode, and is this is done
+  when the combo PHY is probed.
+
+  The combo PHY uses an external oscillator as a reference clock.
+  During normal operation, the PCIe or USB port driver is responsible
+  for ensuring all other clocks needed by a PHY are enabled, and all
+  resets affecting the PHY are deasserted.  However, for the combo
+  PHY to perform calibration independent of whether it's later used
+  for PCIe or USB, all PCIe mode clocks and resets must be defined.
+
+properties:
+  compatible:
+    const: spacemit,k1-combo-phy
+
+  reg:
+    items:
+      - description: PHY control registers
+
+  clocks:
+    items:
+      - description: External oscillator used by the PHY PLL
+      - description: DWC PCIe Data Bus Interface (DBI) clock
+      - description: DWC PCIe application AXI-bus Master interface clock
+      - description: DWC PCIe application AXI-bus slave interface clock
+
+  clock-names:
+    items:
+      - const: refclk
+      - const: dbi
+      - const: mstr
+      - const: slv
+
+  resets:
+    items:
+      - description: PHY reset; remains deasserted after initialization
+      - description: DWC PCIe Data Bus Interface (DBI) reset
+      - description: DWC PCIe application AXI-bus Master interface reset
+      - description: DWC PCIe application AXI-bus slave interface reset
+
+  reset-names:
+    items:
+      - const: phy
+      - const: dbi
+      - const: mstr
+      - const: slv
+
+  spacemit,apmu:
+    description:
+      A phandle that refers to the APMU system controller, whose
+      regmap is used in setting the mode
+    $ref: /schemas/types.yaml#/definitions/phandle
+
+  "#phy-cells":
+    const: 1
+    description:
+      The argument value (PHY_TYPE_PCIE or PHY_TYPE_USB3) determines
+      whether the PHY operates in PCIe or USB3 mode.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - resets
+  - reset-names
+  - spacemit,apmu
+  - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/spacemit,k1-syscon.h>
+    phy@c0b10000 {
+        compatible = "spacemit,k1-combo-phy";
+        reg = <0xc0b10000 0x1000>;
+        clocks = <&vctcxo_24m>,
+                 <&syscon_apmu CLK_PCIE0_DBI>,
+                 <&syscon_apmu CLK_PCIE0_MASTER>,
+                 <&syscon_apmu CLK_PCIE0_SLAVE>;
+        clock-names = "refclk",
+                      "dbi",
+                      "mstr",
+                      "slv";
+        resets = <&syscon_apmu RESET_PCIE0_GLOBAL>,
+                 <&syscon_apmu RESET_PCIE0_DBI>,
+                 <&syscon_apmu RESET_PCIE0_MASTER>,
+                 <&syscon_apmu RESET_PCIE0_SLAVE>;
+        reset-names = "phy",
+                      "dbi",
+                      "mstr",
+                      "slv";
+        spacemit,apmu = <&syscon_apmu>;
+        #phy-cells = <1>;
+    };
-- 
2.48.1

[PATCH v4 2/7] dt-bindings: phy: spacemit: introduce PCIe PHY

[Alex Elder]

Add the Device Tree binding for two PCIe PHYs present on the SpacemiT
K1 SoC.  These PHYs are dependent on a separate combo PHY, which
determines at probe time the calibration values used by the PCIe-only
PHYs.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../bindings/phy/spacemit,k1-pcie-phy.yaml    | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/spacemit,k1-pcie-phy.yaml

diff --git a/Documentation/devicetree/bindings/phy/spacemit,k1-pcie-phy.yaml b/Documentation/devicetree/bindings/phy/spacemit,k1-pcie-phy.yaml
new file mode 100644
index 0000000000000..019b28349be75
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/spacemit,k1-pcie-phy.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/spacemit,k1-pcie-phy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SpacemiT K1 PCIe PHY
+
+maintainers:
+  - Alex Elder <elder@riscstar.com>
+
+description: >
+  Two PHYs on the SpacemiT K1 SoC used for only for PCIe.  These
+  PHYs must be configured using calibration values that are
+  determined by a third "combo PHY".  The combo PHY determines
+  these calibration values during probe so they can be used for
+  the two PCIe-only PHYs.
+
+  The PHY uses an external oscillator as a reference clock.  During
+  normal operation, the PCIe host driver is responsible for ensuring
+  all other clocks needed by a PHY are enabled, and all resets
+  affecting the PHY are deasserted.
+
+properties:
+  compatible:
+    const: spacemit,k1-pcie-phy
+
+  reg:
+    items:
+      - description: PHY control registers
+
+  clocks:
+    items:
+      - description: External oscillator used by the PHY PLL
+
+  clock-names:
+    const: refclk
+
+  resets:
+    items:
+      - description: PHY reset; remains deasserted after initialization
+
+  reset-names:
+    const: phy
+
+  "#phy-cells":
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - resets
+  - reset-names
+  - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/spacemit,k1-syscon.h>
+    phy@c0c10000 {
+        compatible = "spacemit,k1-pcie-phy";
+        reg = <0xc0c10000 0x1000>;
+        clocks = <&vctcxo_24m>;
+        clock-names = "refclk";
+        resets = <&syscon_apmu RESET_PCIE1_GLOBAL>;
+        reset-names = "phy";
+        #phy-cells = <0>;
+    };
-- 
2.48.1

[PATCH v4 3/7] dt-bindings: pci: spacemit: introduce PCIe host controller

[Alex Elder]

Add the Device Tree binding for the PCIe root complex found on the
SpacemiT K1 SoC.  This device is derived from the Synopsys Designware
PCIe IP.  It supports up to three PCIe ports operating at PCIe gen 2
link speeds (5 GT/sec).  One of the ports uses a combo PHY, which is
typically used to support a USB 3 port.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../bindings/pci/spacemit,k1-pcie-host.yaml   | 157 ++++++++++++++++++
 1 file changed, 157 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml

diff --git a/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
new file mode 100644
index 0000000000000..58239a155ecc0
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
@@ -0,0 +1,157 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/spacemit,k1-pcie-host.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SpacemiT K1 PCI Express Host Controller
+
+maintainers:
+  - Alex Elder <elder@riscstar.com>
+
+description: >
+  The SpacemiT K1 SoC PCIe host controller is based on the Synopsys
+  DesignWare PCIe IP.  The controller uses the DesignWare built-in
+  MSI interrupt controller, and supports 256 MSIs.
+
+allOf:
+  - $ref: /schemas/pci/snps,dw-pcie.yaml#
+
+properties:
+  compatible:
+    const: spacemit,k1-pcie
+
+  reg:
+    items:
+      - description: DesignWare PCIe registers
+      - description: ATU address space
+      - description: PCIe configuration space
+      - description: Link control registers
+
+  reg-names:
+    items:
+      - const: dbi
+      - const: atu
+      - const: config
+      - const: link
+
+  clocks:
+    items:
+      - description: DWC PCIe Data Bus Interface (DBI) clock
+      - description: DWC PCIe application AXI-bus master interface clock
+      - description: DWC PCIe application AXI-bus slave interface clock
+
+  clock-names:
+    items:
+      - const: dbi
+      - const: mstr
+      - const: slv
+
+  resets:
+    items:
+      - description: DWC PCIe Data Bus Interface (DBI) reset
+      - description: DWC PCIe application AXI-bus master interface reset
+      - description: DWC PCIe application AXI-bus slave interface reset
+
+  reset-names:
+    items:
+      - const: dbi
+      - const: mstr
+      - const: slv
+
+  interrupts:
+    items:
+      - description: Interrupt used for MSIs
+
+  interrupt-names:
+    const: msi
+
+  spacemit,apmu:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description:
+      A phandle that refers to the APMU system controller, whose
+      regmap is used in managing resets and link state, along with
+      and offset of its reset control register.
+    items:
+      - items:
+          - description: phandle to APMU system controller
+          - description: register offset
+
+patternProperties:
+  '^pcie?@':
+    type: object
+    $ref: /schemas/pci/pci-pci-bridge.yaml#
+
+    properties:
+      phys:
+        maxItems: 1
+
+      vpcie3v3-supply:
+        description:
+          A phandle for 3.3v regulator to use for PCIe
+
+    required:
+      - phys
+      - vpcie3v3-supply
+
+    unevaluatedProperties: false
+
+required:
+  - clocks
+  - clock-names
+  - resets
+  - reset-names
+  - interrupts
+  - interrupt-names
+  - spacemit,apmu
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/spacemit,k1-syscon.h>
+    pcie@ca400000 {
+        device_type = "pci";
+        compatible = "spacemit,k1-pcie";
+        reg = <0xca400000 0x00001000>,
+              <0xca700000 0x0001ff24>,
+              <0x9f000000 0x00002000>,
+              <0xc0c20000 0x00001000>;
+        reg-names = "dbi",
+                    "atu",
+                    "config",
+                    "link";
+        #address-cells = <3>;
+        #size-cells = <2>;
+        ranges = <0x01000000 0x0 0x00000000 0x9f002000 0x0 0x00100000>,
+                 <0x02000000 0x0 0x90000000 0x90000000 0x0 0x0f000000>;
+        interrupts = <142>;
+        interrupt-names = "msi";
+        clocks = <&syscon_apmu CLK_PCIE1_DBI>,
+                 <&syscon_apmu CLK_PCIE1_MASTER>,
+                 <&syscon_apmu CLK_PCIE1_SLAVE>;
+        clock-names = "dbi",
+                      "mstr",
+                      "slv";
+        resets = <&syscon_apmu RESET_PCIE1_DBI>,
+                 <&syscon_apmu RESET_PCIE1_MASTER>,
+                 <&syscon_apmu RESET_PCIE1_SLAVE>;
+        reset-names = "dbi",
+                      "mstr",
+                      "slv";
+        pinctrl-names = "default";
+        pinctrl-0 = <&pcie1_3_cfg>;
+        spacemit,apmu = <&syscon_apmu 0x3d4>;
+
+        pcie@0 {
+          device_type = "pci";
+          compatible = "pciclass,0604";
+          reg = <0x0 0x0 0x0 0x0 0x0>;
+          bus-range = <0x01 0xff>;
+          #address-cells = <3>;
+          #size-cells = <2>;
+          ranges;
+          phys = <&pcie1_phy>;
+          vpcie3v3-supply = <&pcie_vcc_3v3>;
+        };
+    };
-- 
2.48.1

[PATCH v4 4/7] phy: spacemit: introduce PCIe/combo PHY

[Alex Elder]

Introduce a driver that supports three PHYs found on the SpacemiT
K1 SoC.  The first PHY is a combo PHY that can be configured for
use for either USB 3 or PCIe.  The other two PHYs support PCIe
only.

All three PHYs must be programmed with an 8 bit receiver termination
value, which must be determined dynamically.  Only the combo PHY is
able to determine this value.  The combo PHY performs a special
calibration step at probe time to discover this, and that value is
used to program each PHY that operates in PCIe mode.  The combo
PHY must therefore be probed before either of the PCIe-only PHYs
will be used.

Each PHY has an internal PLL driven from an external oscillator.
This PLL started when the PHY is first initialized, and stays
on thereafter.

During normal operation, the USB or PCIe driver using the PHY must
ensure (other) clocks and resets are set up properly.

However PCIe mode clocks are enabled and resets are de-asserted
temporarily by this driver to perform the calibration step on the
combo PHY.

Tested-by: Junzhong Pan <panjunzhong@linux.spacemit.com>
Signed-off-by: Alex Elder <elder@riscstar.com>
---
 drivers/phy/Kconfig                |  11 +
 drivers/phy/Makefile               |   1 +
 drivers/phy/phy-spacemit-k1-pcie.c | 670 +++++++++++++++++++++++++++++
 3 files changed, 682 insertions(+)
 create mode 100644 drivers/phy/phy-spacemit-k1-pcie.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 678dd0452f0aa..1984c2e56122e 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -101,6 +101,17 @@ config PHY_NXP_PTN3222
 	  schemes. It supports all three USB 2.0 data rates: Low Speed, Full
 	  Speed and High Speed.
 
+config PHY_SPACEMIT_K1_PCIE
+	tristate "PCIe and combo PHY driver for the SpacemiT K1 SoC"
+	depends on ARCH_SPACEMIT || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
+	select GENERIC_PHY
+	default ARCH_SPACEMIT
+	help
+	  Enable support for the PCIe and USB 3 combo PHY and two
+	  PCIe-only PHYs used in the SpacemiT K1 SoC.
+
 source "drivers/phy/allwinner/Kconfig"
 source "drivers/phy/amlogic/Kconfig"
 source "drivers/phy/broadcom/Kconfig"
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index bfb27fb5a4942..a206133a35151 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_PHY_SNPS_EUSB2)		+= phy-snps-eusb2.o
 obj-$(CONFIG_USB_LGM_PHY)		+= phy-lgm-usb.o
 obj-$(CONFIG_PHY_AIROHA_PCIE)		+= phy-airoha-pcie.o
 obj-$(CONFIG_PHY_NXP_PTN3222)		+= phy-nxp-ptn3222.o
+obj-$(CONFIG_PHY_SPACEMIT_K1_PCIE)	+= phy-spacemit-k1-pcie.o
 obj-y					+= allwinner/	\
 					   amlogic/	\
 					   broadcom/	\
diff --git a/drivers/phy/phy-spacemit-k1-pcie.c b/drivers/phy/phy-spacemit-k1-pcie.c
new file mode 100644
index 0000000000000..75477bea7f700
--- /dev/null
+++ b/drivers/phy/phy-spacemit-k1-pcie.c
@@ -0,0 +1,670 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SpacemiT K1 PCIe and PCIe/USB 3 combo PHY driver
+ *
+ * Copyright (C) 2025 by RISCstar Solutions Corporation.  All rights reserved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include <dt-bindings/phy/phy.h>
+
+/*
+ * Three PCIe ports are supported in the SpacemiT K1 SoC, and this driver
+ * supports their PHYs.
+ *
+ * The PHY for PCIe port A is different from the PHYs for ports B and C:
+ * - It has one lane, while ports B and C have two
+ * - It is a combo PHY can be used for PCIe or USB 3
+ * - It can automatically calibrate PCIe TX and RX termination settings
+ *
+ * The PHY functionality for PCIe ports B and C is identical:
+ * - They have two PCIe lanes (but can be restricted to 1 via device tree)
+ * - They are used for PCIe only
+ * - They are configured using TX and RX values computed for port A
+ *
+ * A given board is designed to use the combo PHY for either PCIe or USB 3.
+ * Whether the combo PHY is configured for PCIe or USB 3 is specified in
+ * device tree using a phandle plus an argument.  The argument indicates
+ * the type (either PHY_TYPE_PCIE or PHY_TYPE_USB3).
+ *
+ * Each PHY has a reset that it gets and deasserts during initialization.
+ * Each depends also on other clocks and resets provided by the controller
+ * hardware (PCIe or USB) it is associated with.  The controller drivers
+ * are required to enable any clocks and de-assert any resets that affect
+ * PHY operation.  In addition each PHY implements an internal PLL, driven
+ * by an external (24 MHz) oscillator.
+ *
+ * PCIe PHYs must be programmed with RX and TX calibration values.  The
+ * combo PHY is the only one that can determine these values.  They are
+ * determined by temporarily enabling the combo PHY in PCIe mode at probe
+ * time (if necessary).  This calibration only needs to be done once, and
+ * when it has completed the TX and RX values are saved.
+ *
+ * To allow the combo PHY to be enabled for calibration, the resets and
+ * clocks it uses in PCIe mode must be supplied.
+ */
+
+struct k1_pcie_phy {
+	struct device *dev;		/* PHY provider device */
+	struct phy *phy;
+	void __iomem *regs;
+	u32 pcie_lanes;			/* Max (1 or 2) unless limited by DT */
+	struct clk *pll;
+	struct clk_hw pll_hw;		/* Private PLL clock */
+
+	/* The remaining fields are only used for the combo PHY */
+	u32 type;			/* PHY_TYPE_PCIE or PHY_TYPE_USB3 */
+	struct regmap *pmu;		/* MMIO regmap (no errors) */
+};
+
+#define CALIBRATION_TIMEOUT		500000	/* For combo PHY (usec) */
+#define PLL_TIMEOUT			500000	/* For PHY PLL lock (usec) */
+#define POLL_DELAY			500	/* Time between polls (usec) */
+
+/* Selecting the combo PHY operating mode requires APMU regmap access */
+#define SYSCON_APMU			"spacemit,apmu"
+
+/* PMU space, for selecting between PCIe and USB 3 mode (combo PHY only) */
+
+#define PMUA_USB_PHY_CTRL0			0x0110
+#define COMBO_PHY_SEL			BIT(3)	/* 0: PCIe; 1: USB 3 */
+
+#define PCIE_CLK_RES_CTRL			0x03cc
+#define PCIE_APP_HOLD_PHY_RST		BIT(30)
+
+/* PHY register space */
+
+/* Offset between lane 0 and lane 1 registers when there are two */
+#define PHY_LANE_OFFSET				0x0400
+
+/* PHY PLL configuration */
+#define PCIE_PU_ADDR_CLK_CFG			0x0008
+#define PLL_READY			BIT(0)		/* read-only */
+#define CFG_INTERNAL_TIMER_ADJ		GENMASK(10, 7)
+#define TIMER_ADJ_USB		0x2
+#define TIMER_ADJ_PCIE		0x6
+#define CFG_SW_PHY_INIT_DONE		BIT(11)	/* We set after PLL config */
+
+#define PCIE_RC_DONE_STATUS			0x0018
+#define CFG_FORCE_RCV_RETRY		BIT(10)		/* Used for PCIe */
+
+/* PCIe PHY lane calibration; assumes 24MHz input clock */
+#define PCIE_RC_CAL_REG2			0x0020
+#define RC_CAL_TOGGLE			BIT(22)
+#define CLKSEL				GENMASK(31, 29)
+#define CLKSEL_24M		0x3
+
+/* Additional PHY PLL configuration (USB 3 and PCIe) */
+#define PCIE_PU_PLL_1				0x0048
+#define REF_100_WSSC			BIT(12)	/* 1: input is 100MHz, SSC */
+#define FREF_SEL			GENMASK(15, 13)
+#define FREF_24M		0x1
+#define SSC_DEP_SEL			GENMASK(19, 16)
+#define SSC_DEP_NONE		0x0
+#define SSC_DEP_5000PPM		0xa
+
+/* PCIe PHY configuration */
+#define PCIE_PU_PLL_2				0x004c
+#define GEN_REF100			BIT(4)	/* 1: generate 100MHz clk */
+
+#define PCIE_RX_REG1				0x0050
+#define EN_RTERM			BIT(3)
+#define AFE_RTERM_REG			GENMASK(11, 8)
+
+#define PCIE_RX_REG2				0x0054
+#define RX_RTERM_SEL			BIT(5)	/* 0: use AFE_RTERM_REG value */
+
+#define PCIE_LTSSM_DIS_ENTRY			0x005c
+#define CFG_REFCLK_MODE			GENMASK(9, 8)
+#define RFCLK_MODE_DRIVER	0x1
+#define OVRD_REFCLK_MODE		BIT(10)	/* 1: use CFG_RFCLK_MODE */
+
+#define PCIE_TX_REG1				0x0064
+#define TX_RTERM_REG			GENMASK(15, 12)
+#define TX_RTERM_SEL			BIT(25)	/* 1: use TX_RTERM_REG */
+
+/* Zeroed for the combo PHY operating in USB mode */
+#define USB3_TEST_CTRL				0x0068
+
+/* PHY calibration values, determined by the combo PHY at probe time */
+#define PCIE_RCAL_RESULT			0x0084	/* Port A PHY only */
+#define RTERM_VALUE_RX			GENMASK(3, 0)
+#define RTERM_VALUE_TX			GENMASK(7, 4)
+#define R_TUNE_DONE			BIT(10)
+
+static u32 k1_phy_rterm = ~0;     /* Invalid initial value */
+
+/* Save the RX and TX receiver termination values */
+static void k1_phy_rterm_set(u32 val)
+{
+	k1_phy_rterm = val & (RTERM_VALUE_RX | RTERM_VALUE_TX);
+}
+
+static bool k1_phy_rterm_valid(void)
+{
+	/* Valid if no bits outside those we care about are set */
+	return !(k1_phy_rterm & ~(RTERM_VALUE_RX | RTERM_VALUE_TX));
+}
+
+static u32 k1_phy_rterm_rx(void)
+{
+	return FIELD_GET(RTERM_VALUE_RX, k1_phy_rterm);
+}
+
+static u32 k1_phy_rterm_tx(void)
+{
+	return FIELD_GET(RTERM_VALUE_TX, k1_phy_rterm);
+}
+
+/* Only the combo PHY has a PMU pointer defined */
+static bool k1_phy_port_a(struct k1_pcie_phy *k1_phy)
+{
+	return !!k1_phy->pmu;
+}
+
+/* The PLL clocks are driven by the external oscillator */
+static const struct clk_parent_data k1_pcie_phy_data[] = {
+	{ .fw_name = "refclk", },
+};
+
+static struct k1_pcie_phy *clk_hw_to_k1_phy(struct clk_hw *clk_hw)
+{
+	return container_of(clk_hw, struct k1_pcie_phy, pll_hw);
+}
+
+/* USB mode only works on the combo PHY, which has only one lane */
+static void k1_pcie_phy_pll_prepare_usb(struct k1_pcie_phy *k1_phy)
+{
+	void __iomem *regs = k1_phy->regs;
+	u32 val;
+
+	val = readl(regs + PCIE_PU_ADDR_CLK_CFG);
+	val &= ~CFG_INTERNAL_TIMER_ADJ;
+	val |= FIELD_PREP(CFG_INTERNAL_TIMER_ADJ, TIMER_ADJ_USB);
+	writel(val, regs + PCIE_PU_ADDR_CLK_CFG);
+
+	val = readl(regs + PCIE_PU_PLL_1);
+	val &= ~SSC_DEP_SEL;
+	val |= FIELD_PREP(SSC_DEP_SEL, SSC_DEP_5000PPM);
+	writel(val, regs + PCIE_PU_PLL_1);
+}
+
+/* Perform PCIe-specific register updates before starting the PLL clock */
+static void k1_pcie_phy_pll_prepare_pcie(struct k1_pcie_phy *k1_phy)
+{
+	void __iomem *regs = k1_phy->regs;
+	u32 val;
+	u32 i;
+
+	for (i = 0; i < k1_phy->pcie_lanes; i++) {
+		val = readl(regs + PCIE_PU_ADDR_CLK_CFG);
+		val &= ~CFG_INTERNAL_TIMER_ADJ;
+		val |= FIELD_PREP(CFG_INTERNAL_TIMER_ADJ, TIMER_ADJ_PCIE);
+		writel(val, regs + PCIE_PU_ADDR_CLK_CFG);
+
+		regs += PHY_LANE_OFFSET;	/* Next lane */
+	}
+
+	regs = k1_phy->regs;
+	val = readl(regs + PCIE_RC_DONE_STATUS);
+	val |= CFG_FORCE_RCV_RETRY;
+	writel(val, regs + PCIE_RC_DONE_STATUS);
+
+	val = readl(regs + PCIE_PU_PLL_1);
+	val &= ~SSC_DEP_SEL;
+	val |= FIELD_PREP(SSC_DEP_SEL, SSC_DEP_NONE);
+	writel(val, regs + PCIE_PU_PLL_1);
+
+	val = readl(regs + PCIE_PU_PLL_2);
+	val |= GEN_REF100;		/* Enable 100 MHz PLL output clock */
+	writel(val, regs + PCIE_PU_PLL_2);
+}
+
+static int k1_pcie_phy_pll_prepare(struct clk_hw *clk_hw)
+{
+	struct k1_pcie_phy *k1_phy = clk_hw_to_k1_phy(clk_hw);
+	void __iomem *regs = k1_phy->regs;
+	u32 val;
+	u32 i;
+
+	if (k1_phy_port_a(k1_phy) && k1_phy->type == PHY_TYPE_USB3)
+		k1_pcie_phy_pll_prepare_usb(k1_phy);
+	else
+		k1_pcie_phy_pll_prepare_pcie(k1_phy);
+
+	/*
+	 * Disable 100 MHz input reference with spread-spectrum
+	 * clocking and select the 24 MHz clock input frequency
+	 */
+	val = readl(regs + PCIE_PU_PLL_1);
+	val &= ~REF_100_WSSC;
+	val &= ~FREF_SEL;
+	val |= FIELD_PREP(FREF_SEL, FREF_24M);
+	writel(val, regs + PCIE_PU_PLL_1);
+
+	/* Mark PLL configuration done on all lanes */
+	for (i = 0; i < k1_phy->pcie_lanes; i++) {
+		val = readl(regs + PCIE_PU_ADDR_CLK_CFG);
+		val |= CFG_SW_PHY_INIT_DONE;
+		writel(val, regs + PCIE_PU_ADDR_CLK_CFG);
+
+		regs += PHY_LANE_OFFSET;	/* Next lane */
+	}
+
+	/*
+	 * Wait for indication the PHY PLL is locked.  Lanes for ports
+	 * B and C share a PLL, so it's enough to sample just lane 0.
+	 */
+	return readl_poll_timeout(k1_phy->regs + PCIE_PU_ADDR_CLK_CFG,
+				  val, val & PLL_READY,
+				  POLL_DELAY, PLL_TIMEOUT);
+}
+
+/* Prepare implies enable, and once enabled, it's always on */
+static const struct clk_ops k1_pcie_phy_pll_ops = {
+	.prepare	= k1_pcie_phy_pll_prepare,
+};
+
+/* We represent the PHY PLL as a private clock */
+static int k1_pcie_phy_pll_setup(struct k1_pcie_phy *k1_phy)
+{
+	struct clk_hw *hw = &k1_phy->pll_hw;
+	struct device *dev = k1_phy->dev;
+	struct clk_init_data init = { };
+	char *name;
+	int ret;
+
+	name = kasprintf(GFP_KERNEL, "pcie%u_phy_pll", k1_phy->phy->id);
+	if (!name)
+		return -ENOMEM;
+
+	init.name = name;
+	init.ops = &k1_pcie_phy_pll_ops;
+	init.parent_data = k1_pcie_phy_data;
+	init.num_parents = ARRAY_SIZE(k1_pcie_phy_data);
+
+	hw->init = &init;
+
+	ret = devm_clk_hw_register(dev, hw);
+
+	kfree(name);	/* __clk_register() duplicates the name we provide */
+
+	if (ret)
+		return ret;
+
+	k1_phy->pll = devm_clk_hw_get_clk(dev, hw, "pll");
+	if (IS_ERR(k1_phy->pll))
+		return PTR_ERR(k1_phy->pll);
+
+	return 0;
+}
+
+/* Select PCIe or USB 3 mode for the combo PHY. */
+static void k1_combo_phy_sel(struct k1_pcie_phy *k1_phy, bool usb)
+{
+	struct regmap *pmu = k1_phy->pmu;
+
+	/* Only change it if it's not already in the desired state */
+	if (!regmap_test_bits(pmu, PMUA_USB_PHY_CTRL0, COMBO_PHY_SEL) == usb)
+		regmap_assign_bits(pmu, PMUA_USB_PHY_CTRL0, COMBO_PHY_SEL, usb);
+}
+
+static void k1_pcie_phy_init_pcie(struct k1_pcie_phy *k1_phy)
+{
+	u32 rx_rterm = k1_phy_rterm_rx();
+	u32 tx_rterm = k1_phy_rterm_tx();
+	void __iomem *regs;
+	u32 val;
+	int i;
+
+	/* For the combo PHY, set PHY to PCIe mode */
+	if (k1_phy_port_a(k1_phy))
+		k1_combo_phy_sel(k1_phy, false);
+
+	regs = k1_phy->regs;
+	for (i = 0; i < k1_phy->pcie_lanes; i++) {
+		val = readl(regs + PCIE_RX_REG1);
+
+		/* Set RX analog front-end receiver termination value */
+		val &= ~AFE_RTERM_REG;
+		val |= FIELD_PREP(AFE_RTERM_REG, rx_rterm);
+
+		/* And enable refclock receiver termination */
+		val |= EN_RTERM;
+		writel(val, regs + PCIE_RX_REG1);
+
+		val = readl(regs + PCIE_RX_REG2);
+		/* Use PCIE_RX_REG1 AFE_RTERM_REG value */
+		val &= ~RX_RTERM_SEL;
+		writel(val, regs + PCIE_RX_REG2);
+
+		val = readl(regs + PCIE_TX_REG1);
+
+		/* Set TX driver termination value */
+		val &= ~TX_RTERM_REG;
+		val |= FIELD_PREP(TX_RTERM_REG, tx_rterm);
+
+		/* Use PCIE_TX_REG1 TX_RTERM_REG value */
+		val |= TX_RTERM_SEL;
+		writel(val, regs + PCIE_TX_REG1);
+
+		/* Set the input clock to 24 MHz, and clear RC_CAL_TOGGLE */
+		val = readl(regs + PCIE_RC_CAL_REG2);
+		val &= CLKSEL;
+		val |= FIELD_PREP(CLKSEL, CLKSEL_24M);
+		val &= ~RC_CAL_TOGGLE;
+		writel(val, regs + PCIE_RC_CAL_REG2);
+
+		/* Now trigger recalibration by setting RC_CAL_TOGGLE again */
+		val |= RC_CAL_TOGGLE;
+		writel(val, regs + PCIE_RC_CAL_REG2);
+
+		val = readl(regs + PCIE_LTSSM_DIS_ENTRY);
+		/* Override the reference clock; set to refclk driver mode */
+		val |= OVRD_REFCLK_MODE;
+		val &= ~CFG_REFCLK_MODE;
+		val |= FIELD_PREP(CFG_REFCLK_MODE, RFCLK_MODE_DRIVER);
+		writel(val, regs + PCIE_LTSSM_DIS_ENTRY);
+
+		regs += PHY_LANE_OFFSET;	/* Next lane */
+	}
+}
+
+/* Only called for combo PHY */
+static void k1_pcie_phy_init_usb(struct k1_pcie_phy *k1_phy)
+{
+	k1_combo_phy_sel(k1_phy, true);
+
+	/* We're not doing any testing */
+	writel(0, k1_phy->regs + USB3_TEST_CTRL);
+}
+
+static int k1_pcie_phy_init(struct phy *phy)
+{
+	struct k1_pcie_phy *k1_phy = phy_get_drvdata(phy);
+
+	/* Note: port type is only valid for port A (both checks needed) */
+	if (k1_phy_port_a(k1_phy) && k1_phy->type == PHY_TYPE_USB3)
+		k1_pcie_phy_init_usb(k1_phy);
+	else
+		k1_pcie_phy_init_pcie(k1_phy);
+
+
+	return clk_prepare_enable(k1_phy->pll);
+}
+
+static int k1_pcie_phy_exit(struct phy *phy)
+{
+	struct k1_pcie_phy *k1_phy = phy_get_drvdata(phy);
+
+	clk_disable_unprepare(k1_phy->pll);
+
+	return 0;
+}
+
+static const struct phy_ops k1_pcie_phy_ops = {
+	.init		= k1_pcie_phy_init,
+	.exit		= k1_pcie_phy_exit,
+	.owner		= THIS_MODULE,
+};
+
+/*
+ * Get values needed for calibrating PHYs operating in PCIe mode.  Only
+ * the combo PHY is able to do this, and its calibration values are used
+ * for configuring all PCIe PHYs.
+ *
+ * We always need to de-assert the "global" reset on the combo PHY,
+ * because the USB driver depends on it.  If used for PCIe, that driver
+ * will (also) de-assert this, but by leaving it de-asserted for the
+ * combo PHY, the USB driver doesn't have to do this.  Note: although
+ * SpacemiT refers to this as the global reset, we name the "phy" reset.
+ *
+ * In addition, we guarantee the APP_HOLD_PHY_RESET bit is clear for the
+ * combo PHY, so the USB driver doesn't have to manage that either.  The
+ * PCIe driver is free to change this bit for normal operation.
+ *
+ * Calibration only needs to be done once.  It's possible calibration has
+ * already completed (e.g., it might have happened in the boot loader, or
+ * -EPROBE_DEFER might result in this function being called again).  So we
+ * check that early too, to avoid doing it more than once.
+ *
+ * Otherwise we temporarily power up the PHY using the PCIe app clocks
+ * and resets, wait for the hardware to indicate calibration is done,
+ * grab the value, then shut the PHY down again.
+ */
+static int k1_pcie_combo_phy_calibrate(struct k1_pcie_phy *k1_phy)
+{
+	struct reset_control_bulk_data resets[] = {
+		{ .id = "dbi", },
+		{ .id = "mstr", },
+		{ .id = "slv", },
+	};
+	struct clk_bulk_data clocks[] = {
+		{ .id = "dbi", },
+		{ .id = "mstr", },
+		{ .id = "slv", },
+	};
+	struct device *dev = k1_phy->dev;
+	int ret = 0;
+	int val;
+
+	/* Nothing to do if we already set the receiver termination value */
+	if (k1_phy_rterm_valid())
+		return 0;
+
+	/*
+	 * We also guarantee the APP_HOLD_PHY_RESET bit is clear.  We can
+	 * leave this bit clear even if an error happens below.
+	 */
+	regmap_assign_bits(k1_phy->pmu, PCIE_CLK_RES_CTRL,
+			   PCIE_APP_HOLD_PHY_RST, false);
+
+	/* If the calibration already completed (e.g. by U-Boot), we're done */
+	val = readl(k1_phy->regs + PCIE_RCAL_RESULT);
+	if (val & R_TUNE_DONE)
+		goto out_tune_done;
+
+	/* Put the PHY into PCIe mode */
+	k1_combo_phy_sel(k1_phy, false);
+
+	/* Get and enable the PCIe app clocks */
+	ret = clk_bulk_get(dev, ARRAY_SIZE(clocks), clocks);
+	if (ret < 0)
+		goto out_tune_done;
+	ret = clk_bulk_prepare_enable(ARRAY_SIZE(clocks), clocks);
+	if (ret)
+		goto out_put_clocks;
+
+	/* Get the PCIe application resets (not the PHY reset) */
+	ret = reset_control_bulk_get_shared(dev, ARRAY_SIZE(resets), resets);
+	if (ret)
+		goto out_disable_clocks;
+
+	/* De-assert the PCIe application resets */
+	ret = reset_control_bulk_deassert(ARRAY_SIZE(resets), resets);
+	if (ret)
+		goto out_put_resets;
+
+	/*
+	 * This is the core activity here.  Wait for the hardware to
+	 * signal that it has completed calibration/tuning.  Once it
+	 * has, the register value will contain the values we'll
+	 * use to configure PCIe PHYs.
+	 */
+	ret = readl_poll_timeout(k1_phy->regs + PCIE_RCAL_RESULT,
+				 val, val & R_TUNE_DONE,
+				 POLL_DELAY, CALIBRATION_TIMEOUT);
+
+	/* Clean up.  We're done with the resets and clocks */
+	reset_control_bulk_assert(ARRAY_SIZE(resets), resets);
+out_put_resets:
+	reset_control_bulk_put(ARRAY_SIZE(resets), resets);
+out_disable_clocks:
+	clk_bulk_disable_unprepare(ARRAY_SIZE(clocks), clocks);
+out_put_clocks:
+	clk_bulk_put(ARRAY_SIZE(clocks), clocks);
+out_tune_done:
+	/* If we got the value without timing out, set k1_phy_rterm */
+	if (!ret)
+		k1_phy_rterm_set(val);
+
+	return ret;
+}
+
+static struct phy *
+k1_pcie_combo_phy_xlate(struct device *dev, const struct of_phandle_args *args)
+{
+	struct k1_pcie_phy *k1_phy = dev_get_drvdata(dev);
+	u32 type;
+
+	/* The argument specifying the PHY mode is required */
+	if (args->args_count != 1)
+		return ERR_PTR(-EINVAL);
+
+	/* We only support PCIe and USB 3 mode */
+	type = args->args[0];
+	if (type != PHY_TYPE_PCIE && type != PHY_TYPE_USB3)
+		return ERR_PTR(-EINVAL);
+
+	/* This PHY can only be used once */
+	if (k1_phy->type != PHY_NONE)
+		return ERR_PTR(-EBUSY);
+
+	k1_phy->type = type;
+
+	return k1_phy->phy;
+}
+
+/* Use the maximum number of PCIe lanes unless limited by device tree */
+static u32 k1_pcie_num_lanes(struct k1_pcie_phy *k1_phy, bool port_a)
+{
+	struct device *dev = k1_phy->dev;
+	u32 count = 0;
+	u32 max;
+	int ret;
+
+	ret = of_property_read_u32(dev_of_node(dev), "num-lanes", &count);
+	if (count == 1)
+		return 1;
+
+	if (count == 2 && !port_a)
+		return 2;
+
+	max = port_a ? 1 : 2;
+	if (ret != -EINVAL)
+		dev_warn(dev, "bad lane count %u for port; using %u\n",
+			 count, max);
+
+	return max;
+}
+
+static int k1_pcie_combo_phy_probe(struct k1_pcie_phy *k1_phy)
+{
+	struct device *dev = k1_phy->dev;
+	struct regmap *regmap;
+	int ret;
+
+	/* Setting the PHY mode requires access to the PMU regmap */
+	regmap = syscon_regmap_lookup_by_phandle(dev_of_node(dev), SYSCON_APMU);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap), "failed to get PMU\n");
+	k1_phy->pmu = regmap;
+
+	ret = k1_pcie_combo_phy_calibrate(k1_phy);
+	if (ret)
+		return dev_err_probe(dev, ret, "calibration failed\n");
+
+	/* Needed by k1_pcie_combo_phy_xlate(), which also sets k1_phy->type */
+	dev_set_drvdata(dev, k1_phy);
+
+	return 0;
+}
+
+static int k1_pcie_phy_probe(struct platform_device *pdev)
+{
+	struct phy *(*xlate)(struct device *dev,
+			     const struct of_phandle_args *args);
+	struct device *dev = &pdev->dev;
+	struct reset_control *phy_reset;
+	struct phy_provider *provider;
+	struct k1_pcie_phy *k1_phy;
+	bool probing_port_a;
+	int ret;
+
+	xlate = of_device_get_match_data(dev);
+	probing_port_a = xlate == k1_pcie_combo_phy_xlate;
+
+	/* Only the combo PHY can calibrate, so it must probe first */
+	if (!k1_phy_rterm_valid() && !probing_port_a)
+		return -EPROBE_DEFER;
+
+	k1_phy = devm_kzalloc(dev, sizeof(*k1_phy), GFP_KERNEL);
+	if (!k1_phy)
+		return -ENOMEM;
+	k1_phy->dev = dev;
+
+	k1_phy->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(k1_phy->regs))
+		return dev_err_probe(dev, PTR_ERR(k1_phy->regs),
+				     "error mapping registers\n");
+
+	/* De-assert the PHY (global) reset and leave it that way */
+	phy_reset = devm_reset_control_get_exclusive_deasserted(dev, "phy");
+	if (IS_ERR(phy_reset))
+		return PTR_ERR(phy_reset);
+
+	if (probing_port_a) {
+		ret = k1_pcie_combo_phy_probe(k1_phy);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "error probing combo phy\n");
+	}
+
+	k1_phy->pcie_lanes = k1_pcie_num_lanes(k1_phy, probing_port_a);
+
+	k1_phy->phy = devm_phy_create(dev, NULL, &k1_pcie_phy_ops);
+	if (IS_ERR(k1_phy->phy))
+		return dev_err_probe(dev, PTR_ERR(k1_phy->phy),
+				     "error creating phy\n");
+	phy_set_drvdata(k1_phy->phy, k1_phy);
+
+	ret = k1_pcie_phy_pll_setup(k1_phy);
+	if (ret)
+		return dev_err_probe(dev, ret, "error initializing clock\n");
+
+	provider = devm_of_phy_provider_register(dev, xlate);
+	if (IS_ERR(provider))
+		return dev_err_probe(dev, PTR_ERR(provider),
+				     "error registering provider\n");
+	return 0;
+}
+
+static const struct of_device_id k1_pcie_phy_of_match[] = {
+	{ .compatible = "spacemit,k1-combo-phy", k1_pcie_combo_phy_xlate, },
+	{ .compatible = "spacemit,k1-pcie-phy", of_phy_simple_xlate, },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, k1_pcie_phy_of_match);
+
+static struct platform_driver k1_pcie_phy_driver = {
+	.probe	= k1_pcie_phy_probe,
+	.driver = {
+		.of_match_table	= k1_pcie_phy_of_match,
+		.name = "spacemit-k1-pcie-phy",
+	}
+};
+module_platform_driver(k1_pcie_phy_driver);
+
+MODULE_DESCRIPTION("SpacemiT K1 PCIe and USB 3 PHY driver");
+MODULE_LICENSE("GPL");
-- 
2.48.1

[PATCH v4 5/7] PCI: spacemit: introduce SpacemiT PCIe host driver

[Alex Elder]

Introduce a driver for the PCIe host controller found in the SpacemiT
K1 SoC.  The hardware is derived from the Synopsys DesignWare PCIe IP.
The driver supports three PCIe ports that operate at PCIe gen2 transfer
rates (5 GT/sec).  The first port uses a combo PHY, which may be
configured for use for USB 3 instead.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 drivers/pci/controller/dwc/Kconfig            |  11 +
 drivers/pci/controller/dwc/Makefile           |   1 +
 drivers/pci/controller/dwc/pcie-spacemit-k1.c | 349 ++++++++++++++++++
 3 files changed, 361 insertions(+)
 create mode 100644 drivers/pci/controller/dwc/pcie-spacemit-k1.c

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 349d4657393c9..d229260f0337e 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -509,6 +509,17 @@ config PCI_KEYSTONE_EP
 	  on DesignWare hardware and therefore the driver re-uses the
 	  DesignWare core functions to implement the driver.
 
+config PCIE_SPACEMIT_K1
+	tristate "SpacemiT K1 PCIe controller (host mode)"
+	depends on ARCH_SPACEMIT || COMPILE_TEST
+	depends on PCI && OF && HAS_IOMEM
+	select PCIE_DW_HOST
+	select PCI_PWRCTRL_SLOT
+	default ARCH_SPACEMIT
+	help
+	  Enables support for the PCIe controller in the K1 SoC operating
+	  in host mode.
+
 config PCIE_VISCONTI_HOST
 	bool "Toshiba Visconti PCIe controller"
 	depends on ARCH_VISCONTI || COMPILE_TEST
diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
index 7ae28f3b0fb39..662b0a219ddc4 100644
--- a/drivers/pci/controller/dwc/Makefile
+++ b/drivers/pci/controller/dwc/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
 obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o
 obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o
 obj-$(CONFIG_PCIE_RCAR_GEN4) += pcie-rcar-gen4.o
+obj-$(CONFIG_PCIE_SPACEMIT_K1) += pcie-spacemit-k1.o
 obj-$(CONFIG_PCIE_STM32_HOST) += pcie-stm32.o
 obj-$(CONFIG_PCIE_STM32_EP) += pcie-stm32-ep.o
 
diff --git a/drivers/pci/controller/dwc/pcie-spacemit-k1.c b/drivers/pci/controller/dwc/pcie-spacemit-k1.c
new file mode 100644
index 0000000000000..2efb92ef948f2
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-spacemit-k1.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SpacemiT K1 PCIe host driver
+ *
+ * Copyright (C) 2025 by RISCstar Solutions Corporation.  All rights reserved.
+ * Copyright (c) 2023, spacemit Corporation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gfp.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mod_devicetable.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+
+#define PCI_VENDOR_ID_SPACEMIT		0x201f
+#define PCI_DEVICE_ID_SPACEMIT_K1	0x0001
+
+/* Offsets and field definitions for link management registers */
+#define K1_PHY_AHB_IRQ_EN			0x0000
+#define PCIE_INTERRUPT_EN		BIT(0)
+
+#define K1_PHY_AHB_LINK_STS			0x0004
+#define SMLH_LINK_UP			BIT(1)
+#define RDLH_LINK_UP			BIT(12)
+
+#define INTR_ENABLE				0x0014
+#define MSI_CTRL_INT			BIT(11)
+
+/* Some controls require APMU regmap access */
+#define SYSCON_APMU			"spacemit,apmu"
+
+/* Offsets and field definitions for APMU registers */
+#define PCIE_CLK_RESET_CONTROL			0x0000
+#define LTSSM_EN			BIT(6)
+#define PCIE_AUX_PWR_DET		BIT(9)
+#define PCIE_RC_PERST			BIT(12)	/* 1: assert PERST# */
+#define APP_HOLD_PHY_RST		BIT(30)
+#define DEVICE_TYPE_RC			BIT(31)	/* 0: endpoint; 1: RC */
+
+#define PCIE_CONTROL_LOGIC			0x0004
+#define PCIE_SOFT_RESET			BIT(0)
+
+struct k1_pcie {
+	struct dw_pcie pci;
+	struct phy *phy;
+	void __iomem *link;
+	struct regmap *pmu;	/* Errors ignored; MMIO-backed regmap */
+	u32 pmu_off;
+};
+
+#define to_k1_pcie(dw_pcie) \
+		platform_get_drvdata(to_platform_device((dw_pcie)->dev))
+
+static void k1_pcie_toggle_soft_reset(struct k1_pcie *k1)
+{
+	u32 offset;
+	u32 val;
+
+	/*
+	 * Write, then read back to guarantee it has reached the device
+	 * before we start the delay.
+	 */
+	offset = k1->pmu_off + PCIE_CONTROL_LOGIC;
+	regmap_set_bits(k1->pmu, offset, PCIE_SOFT_RESET);
+	regmap_read(k1->pmu, offset, &val);
+
+	mdelay(2);
+
+	regmap_clear_bits(k1->pmu, offset, PCIE_SOFT_RESET);
+}
+
+/* Enable app clocks, deassert resets */
+static int k1_pcie_enable_resources(struct k1_pcie *k1)
+{
+	struct dw_pcie *pci = &k1->pci;
+	int ret;
+
+	ret = clk_bulk_prepare_enable(ARRAY_SIZE(pci->app_clks), pci->app_clks);
+	if (ret)
+		return ret;
+
+	ret = reset_control_bulk_deassert(ARRAY_SIZE(pci->app_rsts),
+					  pci->app_rsts);
+	if (ret)
+		goto err_disable_clks;
+
+	return 0;
+
+err_disable_clks:
+	clk_bulk_disable_unprepare(ARRAY_SIZE(pci->app_clks), pci->app_clks);
+
+	return ret;
+}
+
+/* Assert resets, disable app clocks */
+static void k1_pcie_disable_resources(struct k1_pcie *k1)
+{
+	struct dw_pcie *pci = &k1->pci;
+
+	reset_control_bulk_assert(ARRAY_SIZE(pci->app_rsts), pci->app_rsts);
+	clk_bulk_disable_unprepare(ARRAY_SIZE(pci->app_clks), pci->app_clks);
+}
+
+static int k1_pcie_init(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct k1_pcie *k1 = to_k1_pcie(pci);
+	u32 offset;
+	u32 mask;
+	u32 val;
+	int ret;
+
+	k1_pcie_toggle_soft_reset(k1);
+
+	ret = k1_pcie_enable_resources(k1);
+	if (ret)
+		return ret;
+
+	ret = phy_init(k1->phy);
+	if (ret) {
+		k1_pcie_disable_resources(k1);
+
+		return ret;
+	}
+
+	/* Set the PCI vendor and device ID */
+	dw_pcie_dbi_ro_wr_en(pci);
+	dw_pcie_writew_dbi(pci, PCI_VENDOR_ID, PCI_VENDOR_ID_SPACEMIT);
+	dw_pcie_writew_dbi(pci, PCI_DEVICE_ID, PCI_DEVICE_ID_SPACEMIT_K1);
+	dw_pcie_dbi_ro_wr_dis(pci);
+
+	/*
+	 * Assert fundamental reset (drive PERST# low).  Put the controller
+	 * in root complex mode, and indicate that Vaux (3.3v) is present.
+	 */
+	mask = PCIE_RC_PERST;
+	mask |= DEVICE_TYPE_RC | PCIE_AUX_PWR_DET;
+
+	/*
+	 * Write, then read back to guarantee it has reached the device
+	 * before we start the delay.
+	 */
+	offset = k1->pmu_off + PCIE_CLK_RESET_CONTROL;
+	regmap_set_bits(k1->pmu, offset, mask);
+	regmap_read(k1->pmu, offset, &val);
+
+	mdelay(PCIE_T_PVPERL_MS);
+
+	/* Deassert fundamental reset (drive PERST# high) */
+	regmap_clear_bits(k1->pmu, offset, PCIE_RC_PERST);
+
+	return 0;
+}
+
+/* Disable ASPM L1 for now, until reported errors can be reproduced */
+static void k1_pcie_post_init(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	u8 offset;
+	u32 val;
+
+	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+
+	dw_pcie_dbi_ro_wr_en(pci);
+
+	/* Turn off ASPM L1 for the link */
+	val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP);
+	val &= ~PCI_EXP_LNKCAP_ASPM_L1;
+	writel(val, pci->dbi_base + offset + PCI_EXP_LNKCAP);
+
+	dw_pcie_dbi_ro_wr_dis(pci);
+}
+
+static void k1_pcie_deinit(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct k1_pcie *k1 = to_k1_pcie(pci);
+
+	/* Assert fundamental reset (drive PERST# low) */
+	regmap_set_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
+			PCIE_RC_PERST);
+
+	phy_exit(k1->phy);
+
+	k1_pcie_disable_resources(k1);
+}
+
+static const struct dw_pcie_host_ops k1_pcie_host_ops = {
+	.init		= k1_pcie_init,
+	.post_init	= k1_pcie_post_init,
+	.deinit		= k1_pcie_deinit,
+};
+
+static bool k1_pcie_link_up(struct dw_pcie *pci)
+{
+	struct k1_pcie *k1 = to_k1_pcie(pci);
+	u32 val;
+
+	val = readl_relaxed(k1->link + K1_PHY_AHB_LINK_STS);
+
+	return (val & RDLH_LINK_UP) && (val & SMLH_LINK_UP);
+}
+
+static int k1_pcie_start_link(struct dw_pcie *pci)
+{
+	struct k1_pcie *k1 = to_k1_pcie(pci);
+	u32 val;
+
+	/* Stop holding the PHY in reset, and enable link training */
+	regmap_update_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
+			   APP_HOLD_PHY_RST | LTSSM_EN, LTSSM_EN);
+
+	/* Enable the MSI interrupt */
+	writel_relaxed(MSI_CTRL_INT, k1->link + INTR_ENABLE);
+
+	/* Top-level interrupt enable */
+	val = readl_relaxed(k1->link + K1_PHY_AHB_IRQ_EN);
+	val |= PCIE_INTERRUPT_EN;
+	writel_relaxed(val, k1->link + K1_PHY_AHB_IRQ_EN);
+
+	return 0;
+}
+
+static void k1_pcie_stop_link(struct dw_pcie *pci)
+{
+	struct k1_pcie *k1 = to_k1_pcie(pci);
+	u32 val;
+
+	/* Disable interrupts */
+	val = readl_relaxed(k1->link + K1_PHY_AHB_IRQ_EN);
+	val &= ~PCIE_INTERRUPT_EN;
+	writel_relaxed(val, k1->link + K1_PHY_AHB_IRQ_EN);
+
+	writel_relaxed(0, k1->link + INTR_ENABLE);
+
+	/* Disable the link and hold the PHY in reset */
+	regmap_update_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
+			   APP_HOLD_PHY_RST | LTSSM_EN, APP_HOLD_PHY_RST);
+}
+
+static const struct dw_pcie_ops k1_pcie_ops = {
+	.link_up	= k1_pcie_link_up,
+	.start_link	= k1_pcie_start_link,
+	.stop_link	= k1_pcie_stop_link,
+};
+
+static int k1_pcie_parse_port(struct k1_pcie *k1)
+{
+	struct device *dev = k1->pci.dev;
+	struct device_node *root_port;
+	struct phy *phy;
+
+	/* We assume only one root port */
+	root_port = of_get_next_available_child(dev_of_node(dev), NULL);
+	if (!root_port)
+		return -EINVAL;
+
+	phy = devm_of_phy_get(dev, root_port, NULL);
+
+	of_node_put(root_port);
+
+	if (IS_ERR(phy))
+		return PTR_ERR(phy);
+
+	k1->phy = phy;
+
+	return 0;
+}
+
+static int k1_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct k1_pcie *k1;
+	int ret;
+
+	k1 = devm_kzalloc(dev, sizeof(*k1), GFP_KERNEL);
+	if (!k1)
+		return -ENOMEM;
+
+	k1->pmu = syscon_regmap_lookup_by_phandle_args(dev_of_node(dev),
+						       SYSCON_APMU, 1,
+						       &k1->pmu_off);
+	if (IS_ERR(k1->pmu))
+		return dev_err_probe(dev, PTR_ERR(k1->pmu),
+				     "failed to lookup PMU registers\n");
+
+	k1->link = devm_platform_ioremap_resource_byname(pdev, "link");
+	if (!k1->link)
+		return dev_err_probe(dev, -ENOMEM,
+				     "failed to map \"link\" registers\n");
+
+	k1->pci.dev = dev;
+	k1->pci.ops = &k1_pcie_ops;
+	dw_pcie_cap_set(&k1->pci, REQ_RES);
+
+	k1->pci.pp.ops = &k1_pcie_host_ops;
+
+	/* Hold the PHY in reset until we start the link */
+	regmap_set_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
+			APP_HOLD_PHY_RST);
+
+	pm_runtime_set_active(dev);
+	pm_runtime_no_callbacks(dev);
+	devm_pm_runtime_enable(dev);
+
+	platform_set_drvdata(pdev, k1);
+
+	ret = k1_pcie_parse_port(k1);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to parse root port\n");
+
+	ret = dw_pcie_host_init(&k1->pci.pp);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to initialize host\n");
+
+	return 0;
+}
+
+static void k1_pcie_remove(struct platform_device *pdev)
+{
+	struct k1_pcie *k1 = platform_get_drvdata(pdev);
+
+	dw_pcie_host_deinit(&k1->pci.pp);
+}
+
+static const struct of_device_id k1_pcie_of_match_table[] = {
+	{ .compatible = "spacemit,k1-pcie", },
+	{ },
+};
+
+static struct platform_driver k1_pcie_driver = {
+	.probe	= k1_pcie_probe,
+	.remove	= k1_pcie_remove,
+	.driver = {
+		.name			= "spacemit-k1-pcie",
+		.of_match_table		= k1_pcie_of_match_table,
+		.probe_type		= PROBE_PREFER_ASYNCHRONOUS,
+	},
+};
+module_platform_driver(k1_pcie_driver);
-- 
2.48.1

[PATCH v4 6/7] riscv: dts: spacemit: add a PCIe regulator

[Alex Elder]

Define a 3.3v fixed voltage regulator to be used by PCIe on the
Banana Pi BPI-F3.  On this platform, this regulator is always on.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
index 33ca816bfd4b3..a269c2cca3ac9 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
@@ -33,6 +33,14 @@ led1 {
 		};
 	};
 
+	pcie_vcc_3v3: pcie-vcc3v3 {
+		compatible = "regulator-fixed";
+		regulator-name = "PCIE_VCC3V3";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-always-on;
+	};
+
 	reg_dc_in: dc-in-12v {
 		compatible = "regulator-fixed";
 		regulator-name = "dc_in_12v";
-- 
2.48.1

[PATCH v4 7/7] riscv: dts: spacemit: PCIe and PHY-related updates

[Alex Elder]

Define PCIe and PHY-related Device Tree nodes for the SpacemiT K1 SoC.

Enable the combo PHY and the two PCIe-only PHYs on the Banana Pi BPI-F3
board.  The combo PHY is used for USB on this board, and that will be
enabled when USB 3 support is accepted.

The combo PHY must perform a calibration step to determine configuration
values used by the PCIe-only PHYs.  As a result, it must be enabled if
either of the other two PHYs is enabled.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../boot/dts/spacemit/k1-bananapi-f3.dts      |  36 ++++
 arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi  |  33 ++++
 arch/riscv/boot/dts/spacemit/k1.dtsi          | 176 ++++++++++++++++++
 3 files changed, 245 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
index a269c2cca3ac9..f1641e219a631 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
@@ -61,6 +61,12 @@ reg_vcc_4v: vcc-4v {
 	};
 };
 
+&combo_phy {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pcie0_3_cfg>;
+	status = "okay";
+};
+
 &emmc {
 	bus-width = <8>;
 	mmc-hs400-1_8v;
@@ -266,6 +272,36 @@ dldo7 {
 	};
 };
 
+&pcie1_phy {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pcie1_3_cfg>;
+	status = "okay";
+};
+
+&pcie1_port {
+	phys = <&pcie1_phy>;
+	vpcie3v3-supply = <&pcie_vcc_3v3>;
+};
+
+&pcie1 {
+	status = "okay";
+};
+
+&pcie2_phy {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pcie2_4_cfg>;
+	status = "okay";
+};
+
+&pcie2_port {
+	phys = <&pcie2_phy>;
+	vpcie3v3-supply = <&pcie_vcc_3v3>;
+};
+
+&pcie2 {
+	status = "okay";
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_2_cfg>;
diff --git a/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
index 4eef81d583f3d..d456dea7bd32a 100644
--- a/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
@@ -509,6 +509,39 @@ uart9-2-pins {
 		};
 	};
 
+	pcie0_3_cfg: pcie0-3-cfg {
+		pcie0-3-pins {
+			pinmux = <K1_PADCONF(54, 3)>,	/* PERST# */
+				 <K1_PADCONF(55, 3)>,	/* WAKE# */
+				 <K1_PADCONF(53, 3)>;	/* CLKREQ# */
+
+			bias-pull-up = <0>;
+			drive-strength = <21>;
+		};
+	};
+
+	pcie1_3_cfg: pcie1-3-cfg {
+		pcie1-3-pins {
+			pinmux = <K1_PADCONF(59, 4)>,	/* PERST# */
+				 <K1_PADCONF(60, 4)>,	/* WAKE# */
+				 <K1_PADCONF(61, 4)>;	/* CLKREQ# */
+
+			bias-pull-up = <0>;
+			drive-strength = <21>;
+		};
+	};
+
+	pcie2_4_cfg: pcie2-4-cfg {
+		pcie2-4-pins {
+			pinmux = <K1_PADCONF(62, 4)>,	/* PERST# */
+				 <K1_PADCONF(112, 3)>,	/* WAKE# */
+				 <K1_PADCONF(117, 4)>;	/* CLKREQ# */
+
+			bias-pull-up = <0>;
+			drive-strength = <21>;
+		};
+	};
+
 	pwm14_1_cfg: pwm14-1-cfg {
 		pwm14-1-pins {
 			pinmux = <K1_PADCONF(44, 4)>;
diff --git a/arch/riscv/boot/dts/spacemit/k1.dtsi b/arch/riscv/boot/dts/spacemit/k1.dtsi
index af35f9cd64351..a20422db101ee 100644
--- a/arch/riscv/boot/dts/spacemit/k1.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1.dtsi
@@ -4,6 +4,7 @@
  */
 
 #include <dt-bindings/clock/spacemit,k1-syscon.h>
+#include <dt-bindings/phy/phy.h>
 
 /dts-v1/;
 / {
@@ -358,6 +359,52 @@ syscon_rcpu2: system-controller@c0888000 {
 			#reset-cells = <1>;
 		};
 
+		combo_phy: phy@c0b10000 {
+			compatible = "spacemit,k1-combo-phy";
+			reg = <0x0 0xc0b10000 0x0 0x1000>;
+			clocks = <&vctcxo_24m>,
+				 <&syscon_apmu CLK_PCIE0_DBI>,
+				 <&syscon_apmu CLK_PCIE0_MASTER>,
+				 <&syscon_apmu CLK_PCIE0_SLAVE>;
+			clock-names = "refclk",
+				      "dbi",
+				      "mstr",
+				      "slv";
+			resets = <&syscon_apmu RESET_PCIE0_GLOBAL>,
+				 <&syscon_apmu RESET_PCIE0_DBI>,
+				 <&syscon_apmu RESET_PCIE0_MASTER>,
+				 <&syscon_apmu RESET_PCIE0_SLAVE>;
+			reset-names = "phy",
+				      "dbi",
+				      "mstr",
+				      "slv";
+			#phy-cells = <1>;
+			spacemit,apmu = <&syscon_apmu>;
+			status = "disabled";
+		};
+
+		pcie1_phy: phy@c0c10000 {
+			compatible = "spacemit,k1-pcie-phy";
+			reg = <0x0 0xc0c10000 0x0 0x1000>;
+			clocks = <&vctcxo_24m>;
+			clock-names = "refclk";
+			resets = <&syscon_apmu RESET_PCIE1_GLOBAL>;
+			reset-names = "phy";
+			#phy-cells = <0>;
+			status = "disabled";
+		};
+
+		pcie2_phy: phy@c0d10000 {
+			compatible = "spacemit,k1-pcie-phy";
+			reg = <0x0 0xc0d10000 0x0 0x1000>;
+			clocks = <&vctcxo_24m>;
+			clock-names = "refclk";
+			resets = <&syscon_apmu RESET_PCIE2_GLOBAL>;
+			reset-names = "phy";
+			#phy-cells = <0>;
+			status = "disabled";
+		};
+
 		syscon_apbc: system-controller@d4015000 {
 			compatible = "spacemit,k1-syscon-apbc";
 			reg = <0x0 0xd4015000 0x0 0x1000>;
@@ -873,6 +920,135 @@ pcie-bus {
 			#size-cells = <2>;
 			dma-ranges = <0x0 0x00000000 0x0 0x00000000 0x0 0x80000000>,
 				     <0x0 0xb8000000 0x1 0x38000000 0x3 0x48000000>;
+			pcie0: pcie@ca000000 {
+				device_type = "pci";
+				compatible = "spacemit,k1-pcie";
+				reg = <0x0 0xca000000 0x0 0x00001000>,
+				      <0x0 0xca300000 0x0 0x0001ff24>,
+				      <0x0 0x8f000000 0x0 0x00002000>,
+				      <0x0 0xc0b20000 0x0 0x00001000>;
+				reg-names = "dbi",
+					    "atu",
+					    "config",
+					    "link";
+				#address-cells = <3>;
+				#size-cells = <2>;
+				ranges = <0x01000000 0x0 0x00000000 0x0 0x8f002000 0x0 0x00100000>,
+					 <0x02000000 0x0 0x80000000 0x0 0x80000000 0x0 0x0f000000>;
+				interrupts = <141>;
+				interrupt-names = "msi";
+				clocks = <&syscon_apmu CLK_PCIE0_DBI>,
+					 <&syscon_apmu CLK_PCIE0_MASTER>,
+					 <&syscon_apmu CLK_PCIE0_SLAVE>;
+				clock-names = "dbi",
+					      "mstr",
+					      "slv";
+				resets = <&syscon_apmu RESET_PCIE0_DBI>,
+					 <&syscon_apmu RESET_PCIE0_MASTER>,
+					 <&syscon_apmu RESET_PCIE0_SLAVE>;
+				reset-names = "dbi",
+					      "mstr",
+					      "slv";
+				spacemit,apmu = <&syscon_apmu 0x03cc>;
+				status = "disabled";
+
+				pcie0_port: pcie@0 {
+					device_type = "pci";
+					compatible = "pciclass,0604";
+					reg = <0x0 0x0 0x0 0x0 0x0>;
+					bus-range = <0x01 0xff>;
+					#address-cells = <3>;
+					#size-cells = <2>;
+					ranges;
+				};
+			};
+
+			pcie1: pcie@ca400000 {
+				device_type = "pci";
+				compatible = "spacemit,k1-pcie";
+				reg = <0x0 0xca400000 0x0 0x00001000>,
+				      <0x0 0xca700000 0x0 0x0001ff24>,
+				      <0x0 0x9f000000 0x0 0x00002000>,
+				      <0x0 0xc0c20000 0x0 0x00001000>;
+				reg-names = "dbi",
+					    "atu",
+					    "config",
+					    "link";
+				#address-cells = <3>;
+				#size-cells = <2>;
+				ranges = <0x01000000 0x0 0x00000000 0x0 0x9f002000 0x0 0x00100000>,
+					 <0x02000000 0x0 0x90000000 0x0 0x90000000 0x0 0x0f000000>;
+				interrupts = <142>;
+				interrupt-names = "msi";
+				clocks = <&syscon_apmu CLK_PCIE1_DBI>,
+					 <&syscon_apmu CLK_PCIE1_MASTER>,
+					 <&syscon_apmu CLK_PCIE1_SLAVE>;
+				clock-names = "dbi",
+					      "mstr",
+					      "slv";
+				resets = <&syscon_apmu RESET_PCIE1_DBI>,
+					 <&syscon_apmu RESET_PCIE1_MASTER>,
+					 <&syscon_apmu RESET_PCIE1_SLAVE>;
+				reset-names = "dbi",
+					      "mstr",
+					      "slv";
+				spacemit,apmu = <&syscon_apmu 0x3d4>;
+				status = "disabled";
+
+				pcie1_port: pcie@0 {
+					device_type = "pci";
+					compatible = "pciclass,0604";
+					reg = <0x0 0x0 0x0 0x0 0x0>;
+					bus-range = <0x01 0xff>;
+					#address-cells = <3>;
+					#size-cells = <2>;
+					ranges;
+				};
+			};
+
+			pcie2: pcie@ca800000 {
+				device_type = "pci";
+				compatible = "spacemit,k1-pcie";
+				reg = <0x0 0xca800000 0x0 0x00001000>,
+				      <0x0 0xcab00000 0x0 0x0001ff24>,
+				      <0x0 0xb7000000 0x0 0x00002000>,
+				      <0x0 0xc0d20000 0x0 0x00001000>;
+				reg-names = "dbi",
+					    "atu",
+					    "config",
+					    "link";
+				#address-cells = <3>;
+				#size-cells = <2>;
+				ranges = <0x01000000 0x0 0x00000000 0x0 0xb7002000 0x0 0x00100000>,
+					 <0x42000000 0x0 0xa0000000 0x0 0xa0000000 0x0 0x10000000>,
+					 <0x02000000 0x0 0xb0000000 0x0 0xb0000000 0x0 0x07000000>;
+				interrupts = <143>;
+				interrupt-names = "msi";
+				clocks = <&syscon_apmu CLK_PCIE2_DBI>,
+					 <&syscon_apmu CLK_PCIE2_MASTER>,
+					 <&syscon_apmu CLK_PCIE2_SLAVE>;
+				clock-names = "dbi",
+					      "mstr",
+					      "slv";
+				resets = <&syscon_apmu RESET_PCIE2_DBI>,
+					 <&syscon_apmu RESET_PCIE2_MASTER>,
+					 <&syscon_apmu RESET_PCIE2_SLAVE>;
+				reset-names = "dbi",
+					      "mstr",
+					      "slv";
+				spacemit,apmu = <&syscon_apmu 0x3dc>;
+				status = "disabled";
+
+				pcie2_port: pcie@0 {
+					device_type = "pci";
+					compatible = "pciclass,0604";
+					reg = <0x0 0x0 0x0 0x0 0x0>;
+					bus-range = <0x01 0xff>;
+					#address-cells = <3>;
+					#size-cells = <2>;
+					ranges;
+				};
+			};
 		};
 
 		storage-bus {
-- 
2.48.1

Re: [PATCH v4 5/7] PCI: spacemit: introduce SpacemiT PCIe host driver

[Bjorn Helgaas]

In subject, capitalize "introduce" to match history.  Or you could
just use "Add ...", which has the advantage of being shorter.

On Thu, Oct 30, 2025 at 05:02:56PM -0500, Alex Elder wrote:
> Introduce a driver for the PCIe host controller found in the SpacemiT
> K1 SoC.  The hardware is derived from the Synopsys DesignWare PCIe IP.
> The driver supports three PCIe ports that operate at PCIe gen2 transfer
> rates (5 GT/sec).  The first port uses a combo PHY, which may be
> configured for use for USB 3 instead.
> ...

I guess this doesn't support INTx interrupts at all?

> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -509,6 +509,17 @@ config PCI_KEYSTONE_EP
>  	  on DesignWare hardware and therefore the driver re-uses the
>  	  DesignWare core functions to implement the driver.
>  
> +config PCIE_SPACEMIT_K1
> +	tristate "SpacemiT K1 PCIe controller (host mode)"

Move this to keep the menu items alphabetized by vendor.

> +	depends on ARCH_SPACEMIT || COMPILE_TEST
> +	depends on PCI && OF && HAS_IOMEM

I don't think you need PCI or OF.

> +	select PCIE_DW_HOST
> +	select PCI_PWRCTRL_SLOT
> +	default ARCH_SPACEMIT
> +	help
> +	  Enables support for the PCIe controller in the K1 SoC operating
> +	  in host mode.

Most help text includes both the vendor and the product line names.

Re: [PATCH v4 3/7] dt-bindings: pci: spacemit: introduce PCIe host controller

[Rob Herring]

On Thu, Oct 30, 2025 at 05:02:54PM -0500, Alex Elder wrote:
> Add the Device Tree binding for the PCIe root complex found on the
> SpacemiT K1 SoC.  This device is derived from the Synopsys Designware
> PCIe IP.  It supports up to three PCIe ports operating at PCIe gen 2
> link speeds (5 GT/sec).  One of the ports uses a combo PHY, which is
> typically used to support a USB 3 port.
> 
> Signed-off-by: Alex Elder <elder@riscstar.com>
> ---
>  .../bindings/pci/spacemit,k1-pcie-host.yaml   | 157 ++++++++++++++++++
>  1 file changed, 157 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
> new file mode 100644
> index 0000000000000..58239a155ecc0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
> @@ -0,0 +1,157 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/spacemit,k1-pcie-host.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SpacemiT K1 PCI Express Host Controller
> +
> +maintainers:
> +  - Alex Elder <elder@riscstar.com>
> +
> +description: >
> +  The SpacemiT K1 SoC PCIe host controller is based on the Synopsys
> +  DesignWare PCIe IP.  The controller uses the DesignWare built-in
> +  MSI interrupt controller, and supports 256 MSIs.

Wrap lines at 80.

> +
> +allOf:
> +  - $ref: /schemas/pci/snps,dw-pcie.yaml#
> +
> +properties:
> +  compatible:
> +    const: spacemit,k1-pcie
> +
> +  reg:
> +    items:
> +      - description: DesignWare PCIe registers
> +      - description: ATU address space
> +      - description: PCIe configuration space
> +      - description: Link control registers
> +
> +  reg-names:
> +    items:
> +      - const: dbi
> +      - const: atu
> +      - const: config
> +      - const: link
> +
> +  clocks:
> +    items:
> +      - description: DWC PCIe Data Bus Interface (DBI) clock
> +      - description: DWC PCIe application AXI-bus master interface clock
> +      - description: DWC PCIe application AXI-bus slave interface clock
> +
> +  clock-names:
> +    items:
> +      - const: dbi
> +      - const: mstr
> +      - const: slv
> +
> +  resets:
> +    items:
> +      - description: DWC PCIe Data Bus Interface (DBI) reset
> +      - description: DWC PCIe application AXI-bus master interface reset
> +      - description: DWC PCIe application AXI-bus slave interface reset
> +
> +  reset-names:
> +    items:
> +      - const: dbi
> +      - const: mstr
> +      - const: slv
> +
> +  interrupts:
> +    items:
> +      - description: Interrupt used for MSIs
> +
> +  interrupt-names:
> +    const: msi
> +
> +  spacemit,apmu:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    description:
> +      A phandle that refers to the APMU system controller, whose
> +      regmap is used in managing resets and link state, along with
> +      and offset of its reset control register.
> +    items:
> +      - items:
> +          - description: phandle to APMU system controller
> +          - description: register offset
> +
> +patternProperties:
> +  '^pcie?@':

It's always PCIe, so drop the '?'.

With that,

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

Re: [PATCH v4 5/7] PCI: spacemit: introduce SpacemiT PCIe host driver

[Alex Elder]

On 10/30/25 6:08 PM, Bjorn Helgaas wrote:
> In subject, capitalize "introduce" to match history.  Or you could
> just use "Add ...", which has the advantage of being shorter.

OK.  I'll capitalize all of them in this series.

> On Thu, Oct 30, 2025 at 05:02:56PM -0500, Alex Elder wrote:
>> Introduce a driver for the PCIe host controller found in the SpacemiT
>> K1 SoC.  The hardware is derived from the Synopsys DesignWare PCIe IP.
>> The driver supports three PCIe ports that operate at PCIe gen2 transfer
>> rates (5 GT/sec).  The first port uses a combo PHY, which may be
>> configured for use for USB 3 instead.
>> ...
> 
> I guess this doesn't support INTx interrupts at all?

It can, but I removed that support first to simplify the task
of converting the original code, and second because I had no way
to test it.  I planned for it to be added at a future date.

>> +++ b/drivers/pci/controller/dwc/Kconfig
>> @@ -509,6 +509,17 @@ config PCI_KEYSTONE_EP
>>   	  on DesignWare hardware and therefore the driver re-uses the
>>   	  DesignWare core functions to implement the driver.
>>   
>> +config PCIE_SPACEMIT_K1
>> +	tristate "SpacemiT K1 PCIe controller (host mode)"
> 
> Move this to keep the menu items alphabetized by vendor.

OK.  I was going by Kconfig option name, but now I see
what you mean.

I'll put it between PCIE_SOPHGO_DW and PCIE_SPEAR13XX.

>> +	depends on ARCH_SPACEMIT || COMPILE_TEST
>> +	depends on PCI && OF && HAS_IOMEM
> 
> I don't think you need PCI or OF.

You're right.  PCI for sure, but it doesn't look like I make
an direct OF calls either.  I'll drop them both.

>> +	select PCIE_DW_HOST
>> +	select PCI_PWRCTRL_SLOT
>> +	default ARCH_SPACEMIT
>> +	help
>> +	  Enables support for the PCIe controller in the K1 SoC operating
>> +	  in host mode.
> 
> Most help text includes both the vendor and the product line names.
I guess I didn't include "SpacemiT".  I'll add that, and will try
to come up with a few more words in the description.

Thanks for your quick response.

					-Alex

Re: [PATCH v4 3/7] dt-bindings: pci: spacemit: introduce PCIe host controller

[Alex Elder]

On 10/30/25 7:58 PM, Rob Herring wrote:
> On Thu, Oct 30, 2025 at 05:02:54PM -0500, Alex Elder wrote:
>> Add the Device Tree binding for the PCIe root complex found on the
>> SpacemiT K1 SoC.  This device is derived from the Synopsys Designware
>> PCIe IP.  It supports up to three PCIe ports operating at PCIe gen 2
>> link speeds (5 GT/sec).  One of the ports uses a combo PHY, which is
>> typically used to support a USB 3 port.
>>
>> Signed-off-by: Alex Elder <elder@riscstar.com>
>> ---
>>   .../bindings/pci/spacemit,k1-pcie-host.yaml   | 157 ++++++++++++++++++
>>   1 file changed, 157 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
>> new file mode 100644
>> index 0000000000000..58239a155ecc0
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pci/spacemit,k1-pcie-host.yaml
>> @@ -0,0 +1,157 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/pci/spacemit,k1-pcie-host.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: SpacemiT K1 PCI Express Host Controller
>> +
>> +maintainers:
>> +  - Alex Elder <elder@riscstar.com>
>> +
>> +description: >
>> +  The SpacemiT K1 SoC PCIe host controller is based on the Synopsys
>> +  DesignWare PCIe IP.  The controller uses the DesignWare built-in
>> +  MSI interrupt controller, and supports 256 MSIs.
> 
> Wrap lines at 80.

OK.

>> +
>> +allOf:
>> +  - $ref: /schemas/pci/snps,dw-pcie.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    const: spacemit,k1-pcie
>> +
>> +  reg:
>> +    items:
>> +      - description: DesignWare PCIe registers
>> +      - description: ATU address space
>> +      - description: PCIe configuration space
>> +      - description: Link control registers
>> +
>> +  reg-names:
>> +    items:
>> +      - const: dbi
>> +      - const: atu
>> +      - const: config
>> +      - const: link
>> +
>> +  clocks:
>> +    items:
>> +      - description: DWC PCIe Data Bus Interface (DBI) clock
>> +      - description: DWC PCIe application AXI-bus master interface clock
>> +      - description: DWC PCIe application AXI-bus slave interface clock
>> +
>> +  clock-names:
>> +    items:
>> +      - const: dbi
>> +      - const: mstr
>> +      - const: slv
>> +
>> +  resets:
>> +    items:
>> +      - description: DWC PCIe Data Bus Interface (DBI) reset
>> +      - description: DWC PCIe application AXI-bus master interface reset
>> +      - description: DWC PCIe application AXI-bus slave interface reset
>> +
>> +  reset-names:
>> +    items:
>> +      - const: dbi
>> +      - const: mstr
>> +      - const: slv
>> +
>> +  interrupts:
>> +    items:
>> +      - description: Interrupt used for MSIs
>> +
>> +  interrupt-names:
>> +    const: msi
>> +
>> +  spacemit,apmu:
>> +    $ref: /schemas/types.yaml#/definitions/phandle-array
>> +    description:
>> +      A phandle that refers to the APMU system controller, whose
>> +      regmap is used in managing resets and link state, along with
>> +      and offset of its reset control register.
>> +    items:
>> +      - items:
>> +          - description: phandle to APMU system controller
>> +          - description: register offset
>> +
>> +patternProperties:
>> +  '^pcie?@':
> 
> It's always PCIe, so drop the '?'.

I'll fix that.

> With that,
> 
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

Thanks for the review.

					-Alex

Re: [PATCH v4 5/7] PCI: spacemit: introduce SpacemiT PCIe host driver

[Aurelien Jarno]

Hi Alex,

On 2025-10-30 17:02, Alex Elder wrote:
> +/* Disable ASPM L1 for now, until reported errors can be reproduced */

Thanks for adding this function.

> +static void k1_pcie_post_init(struct dw_pcie_rp *pp)
> +{
> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> +	u8 offset;
> +	u32 val;
> +
> +	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> +
> +	dw_pcie_dbi_ro_wr_en(pci);
> +
> +	/* Turn off ASPM L1 for the link */
> +	val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP);

Why not using dw_pcie_readl_dbi() instead?

> +	val &= ~PCI_EXP_LNKCAP_ASPM_L1;
> +	writel(val, pci->dbi_base + offset + PCI_EXP_LNKCAP);

And here dw_pcie_writel_dbi()?

> +
> +	dw_pcie_dbi_ro_wr_dis(pci);
> +}
> +
> +static void k1_pcie_deinit(struct dw_pcie_rp *pp)
> +{
> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> +	struct k1_pcie *k1 = to_k1_pcie(pci);
> +
> +	/* Assert fundamental reset (drive PERST# low) */
> +	regmap_set_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
> +			PCIE_RC_PERST);
> +
> +	phy_exit(k1->phy);
> +
> +	k1_pcie_disable_resources(k1);
> +}
> +
> +static const struct dw_pcie_host_ops k1_pcie_host_ops = {
> +	.init		= k1_pcie_init,
> +	.post_init	= k1_pcie_post_init,

Unfortunately, while I can see the effect of the change with for 
instance lspci -vvv, this happens way too late in the device scan 
process, i.e. after pcie_aspm_override_default_link_state() and causes 
L1 to still be enabled.

I have tried to move it earlier, in k1_pcie_init() after writing the 
vendor and device IDs. This works as long as "nvme scan" is run in 
U-Boot. But if I don't run this command, it seems that the change is 
ignored or lost (i.e. I can still see L1 enabled with lspci -vvv).

Moving it at the end of k1_pcie_init() works fine, like moving it at the 
beginning of k1_pcie_start_link(). But my knowledge is too limited to 
know where is the correct place.

Regards
Aurelien

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                     http://aurel32.net

Re: [PATCH v4 4/7] phy: spacemit: introduce PCIe/combo PHY

[kernel test robot]

Hi Alex,

kernel test robot noticed the following build errors:

[auto build test ERROR on 131f3d9446a6075192cdd91f197989d98302faa6]

url:    https://github.com/intel-lab-lkp/linux/commits/Alex-Elder/dt-bindings-phy-spacemit-add-SpacemiT-PCIe-combo-PHY/20251031-060541
base:   131f3d9446a6075192cdd91f197989d98302faa6
patch link:    https://lore.kernel.org/r/20251030220259.1063792-5-elder%40riscstar.com
patch subject: [PATCH v4 4/7] phy: spacemit: introduce PCIe/combo PHY
config: sh-allyesconfig (https://download.01.org/0day-ci/archive/20251103/202511030553.8UVCnq06-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251103/202511030553.8UVCnq06-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511030553.8UVCnq06-lkp@intel.com/

All errors (new ones prefixed by >>):

   sh4-linux-ld: drivers/phy/phy-spacemit-k1-pcie.o: in function `k1_pcie_phy_probe':
>> phy-spacemit-k1-pcie.c:(.text+0x7e4): undefined reference to `devm_clk_hw_register'
>> sh4-linux-ld: phy-spacemit-k1-pcie.c:(.text+0x7ec): undefined reference to `devm_clk_hw_get_clk'
   sh4-linux-ld: drivers/net/phy/air_en8811h.o: in function `en8811h_resume':
   air_en8811h.c:(.text+0x948): undefined reference to `clk_restore_context'
   sh4-linux-ld: drivers/net/phy/air_en8811h.o: in function `en8811h_suspend':
   air_en8811h.c:(.text+0x984): undefined reference to `clk_save_context'
   sh4-linux-ld: drivers/media/i2c/tc358746.o: in function `tc358746_probe':
   tc358746.c:(.text+0x1a68): undefined reference to `devm_clk_hw_register'
   sh4-linux-ld: tc358746.c:(.text+0x1a74): undefined reference to `devm_of_clk_add_hw_provider'
   sh4-linux-ld: tc358746.c:(.text+0x1a78): undefined reference to `of_clk_hw_simple_get'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v4 4/7] phy: spacemit: introduce PCIe/combo PHY

[kernel test robot]

Hi Alex,

kernel test robot noticed the following build errors:

[auto build test ERROR on 131f3d9446a6075192cdd91f197989d98302faa6]

url:    https://github.com/intel-lab-lkp/linux/commits/Alex-Elder/dt-bindings-phy-spacemit-add-SpacemiT-PCIe-combo-PHY/20251031-060541
base:   131f3d9446a6075192cdd91f197989d98302faa6
patch link:    https://lore.kernel.org/r/20251030220259.1063792-5-elder%40riscstar.com
patch subject: [PATCH v4 4/7] phy: spacemit: introduce PCIe/combo PHY
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20251103/202511030652.3CVPb2v3-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251103/202511030652.3CVPb2v3-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511030652.3CVPb2v3-lkp@intel.com/

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "devm_clk_hw_register" [drivers/phy/phy-spacemit-k1-pcie.ko] undefined!
>> ERROR: modpost: "devm_clk_hw_get_clk" [drivers/phy/phy-spacemit-k1-pcie.ko] undefined!
ERROR: modpost: "clk_save_context" [drivers/net/phy/air_en8811h.ko] undefined!
ERROR: modpost: "clk_restore_context" [drivers/net/phy/air_en8811h.ko] undefined!
ERROR: modpost: "__delay" [drivers/net/mdio/mdio-cavium.ko] undefined!
ERROR: modpost: "devm_of_clk_add_hw_provider" [drivers/media/i2c/tc358746.ko] undefined!
ERROR: modpost: "devm_clk_hw_register" [drivers/media/i2c/tc358746.ko] undefined!
ERROR: modpost: "of_clk_hw_simple_get" [drivers/media/i2c/tc358746.ko] undefined!

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v4 5/7] PCI: spacemit: introduce SpacemiT PCIe host driver

[Alex Elder]

On 10/31/25 5:31 PM, Aurelien Jarno wrote:
> Hi Alex,
> 
> On 2025-10-30 17:02, Alex Elder wrote:
>> +/* Disable ASPM L1 for now, until reported errors can be reproduced */
> 
> Thanks for adding this function.
> 
>> +static void k1_pcie_post_init(struct dw_pcie_rp *pp)
>> +{
>> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>> +	u8 offset;
>> +	u32 val;
>> +
>> +	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
>> +
>> +	dw_pcie_dbi_ro_wr_en(pci);
>> +
>> +	/* Turn off ASPM L1 for the link */
>> +	val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP);
> 
> Why not using dw_pcie_readl_dbi() instead?
> 
>> +	val &= ~PCI_EXP_LNKCAP_ASPM_L1;
>> +	writel(val, pci->dbi_base + offset + PCI_EXP_LNKCAP);
> 
> And here dw_pcie_writel_dbi()?
> 
>> +
>> +	dw_pcie_dbi_ro_wr_dis(pci);
>> +}
>> +
>> +static void k1_pcie_deinit(struct dw_pcie_rp *pp)
>> +{
>> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>> +	struct k1_pcie *k1 = to_k1_pcie(pci);
>> +
>> +	/* Assert fundamental reset (drive PERST# low) */
>> +	regmap_set_bits(k1->pmu, k1->pmu_off + PCIE_CLK_RESET_CONTROL,
>> +			PCIE_RC_PERST);
>> +
>> +	phy_exit(k1->phy);
>> +
>> +	k1_pcie_disable_resources(k1);
>> +}
>> +
>> +static const struct dw_pcie_host_ops k1_pcie_host_ops = {
>> +	.init		= k1_pcie_init,
>> +	.post_init	= k1_pcie_post_init,
> 
> Unfortunately, while I can see the effect of the change with for
> instance lspci -vvv, this happens way too late in the device scan
> process, i.e. after pcie_aspm_override_default_link_state() and causes
> L1 to still be enabled.

OK thanks for this information.  I am going to contact you
privately to get more information on your errors (and those
Johannes is reporting) so that I can try to resolve them
before I post the next version of this patch series.

					-Alex

> 
> I have tried to move it earlier, in k1_pcie_init() after writing the
> vendor and device IDs. This works as long as "nvme scan" is run in
> U-Boot. But if I don't run this command, it seems that the change is
> ignored or lost (i.e. I can still see L1 enabled with lspci -vvv).
> 
> Moving it at the end of k1_pcie_init() works fine, like moving it at the
> beginning of k1_pcie_start_link(). But my knowledge is too limited to
> know where is the correct place.
> 
> Regards
> Aurelien
>