[PATCH v4 00/11] thermal: samsung: Add support for Google GS101 TMU

[PATCH v4 00/11] thermal: samsung: Add support for Google GS101 TMU

[Tudor Ambarus]

Add support for the Thermal Management Unit (TMU) on the Google GS101
SoC.

The GS101 TMU implementation utilizes a hybrid architecture where
management is shared between the kernel and the Alive Clock and
Power Manager (ACPM) firmware. This hybrid ACPM TMU architecture is 
also present on other Samsung Exynos SoCs (e.g., AutoV920, Exynos850).

Dependencies
============
- context dependency on the ACPM fixes sent at:
  Link: https://lore.kernel.org/linux-samsung-soc/20260423-acpm-fixes-sashiko-reports-v1-0-2217b790925e@linaro.org/T/#t
- cleanup and prep firmware patches 2, 3, 4, 5, 6, 7: required by the
  thermal driver (patch 8).
- bindings (patch 1): required for DTS validation.
- thermal driver patch 8: required by defconfig (patch 11) - logical
dependency. 

Given the thermal driver is a new addition, I suggest everything to go
through the Samsung SoC tree, with ACKs from the Thermal maintainers.
The MFD and clk maintainers are included because of the cleanup patches
(4 and 5). ACPM updated some structures that the mfd and clk client
drivers are using, so these patches shall naturally go via the Samsung
SoC tree.

If the Thermal maintainers prefer to take the bindings and the thermal
driver patches via their tree we'll need:
- an immutable branch containing the firmware patches from the Samsung
  SoC tree to serve as a base for the thermal driver.
- an immutable branch containing the bindings and the thermal driver
  from the thermal tree to serve as a base for the dts and defconfig.

Architecture Overview
=====================

The hardware supports two parallel control paths. For this
implementation, responsibilities are split as follows:

1. Kernel Responsibility:
- maintain direct memory-mapped access to the interrupt pending
  (INTPEND) registers to identify thermal events.
- map physical hardware interrupts to logical thermal zones.
- coordinate functional operations through the ACPM IPC protocol.

2. Firmware Responsibility (ACPM):
- handle sensor initialization.
- manage thermal thresholds configuration.
- perform temperature acquisition and expose data via IPC.

Sensor Mapping (One-to-Many)
============================

The SoC contains multiple physical temperature sensors, but the ACPM
firmware abstracts these into logical groups (Clusters) for reporting:

- ACPM Sensor 0 (Big Cluster): Aggregates physical sensors 0, 6, 7, 8, 9.
- ACPM Sensor 1 (Mid Cluster): Aggregates physical sensors 4, 5.
- ACPM Sensor 2 (Little Cluster): Aggregates physical sensors 1, 2.

The driver maps physical interrupt bits back to these logical parents.
When an interrupt fires, the driver checks the bitmask in the INTPEND
registers and updates the corresponding logical thermal zone.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
Changes in v4: address sashiko review:
- thermal driver: avoid mixing mutex cleanup helpers with goto statements
- firmware, tmu:
  - remove __packed from union acpm_tmu_msg.
  - return ERR_PTR(-ENODEV) for devm_acpm_get_by_phandle when
    CONFIG_EXYNOS_ACPM_PROTOCOL is disabled. 
- Link to v3: https://lore.kernel.org/r/20260420-acpm-tmu-v3-0-3dc8e93f0b26@linaro.org

Changes in v3:
- thermal driver: use .set_trips() instead of .set_trip_point()
- new cleaning/prerequisite patches for firmware/acpm:
  - firmware: samsung: acpm: Make acpm_ops const and access via pointer
  - firmware: samsung: acpm: Drop redundant _ops suffix in acpm_ops members
  - firmware: samsung: acpm: Consolidate transfer initialization helper
- firmware: acpm: TMU helpers - check return value from the firmware
- overall change: emphasize that the ACPM TMU hibrid approach applies to
  other Samsung SoCs as well (Exynos850, AutoV920).
- dts: drop active trip points, update trip point values
- collect R-b tags
- Link to v2: https://lore.kernel.org/r/20260119-acpm-tmu-v2-0-e02a834f04c6@linaro.org

Changes in v2:
- architecture: switch from a syscon/MFD approach to a thermal-sensor
  node with a phandle to the ACPM interface
- bindings: address Krzysztof's feedback, drop redundencies,
  interrupts description.
- firmware: introduce devm_acpm_get_by_phandle() to standardize IPC
  handle acquisition.
- thermal driver: drop compatible's data and use the static data from
  the driver directly.
- defconfig, make EXYNOS_ACPM_THERMAL a module
- Link to v1: https://lore.kernel.org/r/20260114-acpm-tmu-v1-0-cfe56d93e90f@linaro.org

---
Tudor Ambarus (11):
      dt-bindings: thermal: Add Google GS101 TMU
      firmware: samsung: acpm: Consolidate transfer initialization helper
      firmware: samsung: acpm: Annotate rx_data->cmd with __counted_by_ptr
      firmware: samsung: acpm: Drop redundant _ops suffix in acpm_ops members
      firmware: samsung: acpm: Make acpm_ops const and access via pointer
      firmware: samsung: acpm: Add TMU protocol support
      firmware: samsung: acpm: Add devm_acpm_get_by_phandle helper
      thermal: samsung: Add Exynos ACPM TMU driver GS101
      MAINTAINERS: Add entry for Samsung Exynos ACPM thermal driver
      arm64: dts: exynos: gs101: Add thermal management unit
      arm64: defconfig: enable Exynos ACPM thermal support

 .../bindings/thermal/google,gs101-tmu-top.yaml     |  68 +++
 MAINTAINERS                                        |   8 +
 arch/arm64/boot/dts/exynos/google/gs101-tmu.dtsi   | 136 +++++
 arch/arm64/boot/dts/exynos/google/gs101.dtsi       |  18 +
 arch/arm64/configs/defconfig                       |   1 +
 drivers/clk/samsung/clk-acpm.c                     |   8 +-
 drivers/firmware/samsung/Makefile                  |   1 +
 drivers/firmware/samsung/exynos-acpm-dvfs.c        |  20 +-
 drivers/firmware/samsung/exynos-acpm-pmic.c        |  20 +-
 drivers/firmware/samsung/exynos-acpm-tmu.c         | 240 +++++++++
 drivers/firmware/samsung/exynos-acpm-tmu.h         |  28 ++
 drivers/firmware/samsung/exynos-acpm.c             | 113 +++--
 drivers/firmware/samsung/exynos-acpm.h             |   2 +
 drivers/mfd/sec-acpm.c                             |   6 +-
 drivers/thermal/samsung/Kconfig                    |  17 +
 drivers/thermal/samsung/Makefile                   |   2 +
 drivers/thermal/samsung/acpm-tmu.c                 | 547 +++++++++++++++++++++
 .../linux/firmware/samsung/exynos-acpm-protocol.h  |  32 +-
 18 files changed, 1195 insertions(+), 72 deletions(-)
---
base-commit: 2e68039281932e6dc37718a1ea7cbb8e2cda42e6
change-id: 20260113-acpm-tmu-27e21f0e2c3b
prerequisite-change-id: 20260423-acpm-fixes-sashiko-reports-ae28b6ed5581:v1
prerequisite-patch-id: 18d89d0e2bc0efe2cb366746ac4db36f4682f061
prerequisite-patch-id: eb4f90add371877a1930c442c5464c4da7242889
prerequisite-patch-id: 021cd1ee6d2b93f554dd5098cd1158977294dc41
prerequisite-patch-id: b5da16b5c6d6731ea519ed68302fd52ce57c7ffa

Best regards,
-- 
Tudor Ambarus <tudor.ambarus@linaro.org>

[PATCH v4 01/11] dt-bindings: thermal: Add Google GS101 TMU

[Tudor Ambarus]

Document the Thermal Management Unit (TMU) found on the Google GS101 SoC.

The GS101 TMU utilizes a hybrid control model shared between the
Application Processor (AP) and the ACPM (Alive Clock and Power Manager)
firmware. This hybrid ACPM TMU architecture is also present on other
Samsung Exynos SoCs (e.g., AutoV920, Exynos850).

While the TMU is a standard memory-mapped IP block, on this platform
the AP's direct register access is restricted to the interrupt pending
(INTPEND) registers for event identification. High-level functional
tasks, such as sensor initialization, threshold programming, and
temperature reads, are delegated to the ACPM firmware.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
---
 .../bindings/thermal/google,gs101-tmu-top.yaml     | 68 ++++++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml b/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
new file mode 100644
index 000000000000..d0eb2393d581
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
@@ -0,0 +1,68 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/thermal/google,gs101-tmu-top.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung Exynos ACPM Thermal Management Unit (TMU)
+
+maintainers:
+  - Tudor Ambarus <tudor.ambarus@linaro.org>
+
+description:
+  The Samsung Exynos ACPM TMU is a thermal sensor block found on Exynos
+  based platforms (such as Google GS101 and Exynos850). It supports
+  both direct register-level access and firmware-mediated management
+  via the ACPM (Alive Clock and Power Manager) firmware.
+
+  On these platforms, the hardware is managed in a hybrid fashion. The
+  Application Processor (AP) maintains direct memory-mapped access
+  exclusively to the interrupt pending registers to identify thermal
+  events. All other functional aspects - including sensor
+  initialization, threshold configuration, and temperature acquisition
+  - are handled by the ACPM firmware. The AP coordinates these
+  operations through the ACPM IPC protocol.
+
+properties:
+  compatible:
+    const: google,gs101-tmu-top
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: APB peripheral clock (PCLK) for TMU register access.
+
+  interrupts:
+    maxItems: 1
+
+  "#thermal-sensor-cells":
+    const: 1
+
+  samsung,acpm-ipc:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: Phandle to the ACPM IPC node.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - interrupts
+  - "#thermal-sensor-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/google,gs101.h>
+
+    thermal-sensor@100a0000 {
+        compatible = "google,gs101-tmu-top";
+        reg = <0x100a0000 0x800>;
+        clocks = <&cmu_misc CLK_GOUT_MISC_TMU_TOP_PCLK>;
+        interrupts = <GIC_SPI 769 IRQ_TYPE_LEVEL_HIGH 0>;
+        #thermal-sensor-cells = <1>;
+        samsung,acpm-ipc = <&acpm_ipc>;
+    };

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 02/11] firmware: samsung: acpm: Consolidate transfer initialization helper

[Tudor Ambarus]

Both the DVFS and PMIC ACPM sub-drivers implement their own identical
local helper functions (acpm_dvfs_set_xfer and acpm_pmic_set_xfer) to
initialize the acpm_xfer structure before sending an IPC message.

Move this logic into a single centralized helper, acpm_set_xfer(),
in the core ACPM driver to reduce boilerplate and code duplication.
In addition to cleaning up the DVFS and PMIC implementations, this
centralized method will also be utilized by the upcoming Exynos ACPM
Thermal Management Unit (TMU) driver.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/firmware/samsung/exynos-acpm-dvfs.c | 20 ++------------------
 drivers/firmware/samsung/exynos-acpm-pmic.c | 20 +++++---------------
 drivers/firmware/samsung/exynos-acpm.c      | 26 ++++++++++++++++++++++++++
 drivers/firmware/samsung/exynos-acpm.h      |  2 ++
 4 files changed, 35 insertions(+), 33 deletions(-)

diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.c b/drivers/firmware/samsung/exynos-acpm-dvfs.c
index fdea7aa24ca0..7266312ef5a6 100644
--- a/drivers/firmware/samsung/exynos-acpm-dvfs.c
+++ b/drivers/firmware/samsung/exynos-acpm-dvfs.c
@@ -21,22 +21,6 @@
 #define ACPM_DVFS_FREQ_REQ		0
 #define ACPM_DVFS_FREQ_GET		1
 
-static void acpm_dvfs_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdlen,
-			       unsigned int acpm_chan_id, bool response)
-{
-	xfer->acpm_chan_id = acpm_chan_id;
-	xfer->txcnt = cmdlen;
-	xfer->txd = cmd;
-
-	if (response) {
-		xfer->rxcnt = cmdlen;
-		xfer->rxd = cmd;
-	} else {
-		xfer->rxcnt = 0;
-		xfer->rxd = NULL;
-	}
-}
-
 static void acpm_dvfs_init_set_rate_cmd(u32 cmd[4], unsigned int clk_id,
 					unsigned long rate)
 {
@@ -54,7 +38,7 @@ int acpm_dvfs_set_rate(struct acpm_handle *handle,
 	u32 cmd[4];
 
 	acpm_dvfs_init_set_rate_cmd(cmd, clk_id, rate);
-	acpm_dvfs_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, false);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, false);
 
 	return acpm_do_xfer(handle, &xfer);
 }
@@ -74,7 +58,7 @@ unsigned long acpm_dvfs_get_rate(struct acpm_handle *handle,
 	int ret;
 
 	acpm_dvfs_init_get_rate_cmd(cmd, clk_id);
-	acpm_dvfs_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
diff --git a/drivers/firmware/samsung/exynos-acpm-pmic.c b/drivers/firmware/samsung/exynos-acpm-pmic.c
index 0c50993cc9a8..f032f2c69685 100644
--- a/drivers/firmware/samsung/exynos-acpm-pmic.c
+++ b/drivers/firmware/samsung/exynos-acpm-pmic.c
@@ -58,16 +58,6 @@ static inline u32 acpm_pmic_get_bulk(u32 data, unsigned int i)
 	return (data >> (ACPM_PMIC_BULK_SHIFT * i)) & ACPM_PMIC_BULK_MASK;
 }
 
-static void acpm_pmic_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdlen,
-			       unsigned int acpm_chan_id)
-{
-	xfer->txd = cmd;
-	xfer->rxd = cmd;
-	xfer->txcnt = cmdlen;
-	xfer->rxcnt = cmdlen;
-	xfer->acpm_chan_id = acpm_chan_id;
-}
-
 static void acpm_pmic_init_read_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan)
 {
 	cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
@@ -86,7 +76,7 @@ int acpm_pmic_read_reg(struct acpm_handle *handle,
 	int ret;
 
 	acpm_pmic_init_read_cmd(cmd, type, reg, chan);
-	acpm_pmic_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
@@ -119,7 +109,7 @@ int acpm_pmic_bulk_read(struct acpm_handle *handle,
 		return -EINVAL;
 
 	acpm_pmic_init_bulk_read_cmd(cmd, type, reg, chan, count);
-	acpm_pmic_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
@@ -159,7 +149,7 @@ int acpm_pmic_write_reg(struct acpm_handle *handle,
 	int ret;
 
 	acpm_pmic_init_write_cmd(cmd, type, reg, chan, value);
-	acpm_pmic_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
@@ -199,7 +189,7 @@ int acpm_pmic_bulk_write(struct acpm_handle *handle,
 		return -EINVAL;
 
 	acpm_pmic_init_bulk_write_cmd(cmd, type, reg, chan, count, buf);
-	acpm_pmic_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
@@ -229,7 +219,7 @@ int acpm_pmic_update_reg(struct acpm_handle *handle,
 	int ret;
 
 	acpm_pmic_init_update_cmd(cmd, type, reg, chan, value, mask);
-	acpm_pmic_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id);
+	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
 
 	ret = acpm_do_xfer(handle, &xfer);
 	if (ret)
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index 896fbdc2700e..c4aca61a63e4 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -470,6 +470,32 @@ int acpm_do_xfer(struct acpm_handle *handle, const struct acpm_xfer *xfer)
 	return acpm_wait_for_message_response(achan, xfer);
 }
 
+/**
+ * acpm_set_xfer() - initialize an ACPM IPC transfer structure.
+ * @xfer:	pointer to the ACPM transfer structure that is being initialized.
+ * @cmd:	pointer to the buffer containing the command to be transmitted
+ *              to the ACPM firmware.
+ * @cmdcnt:	length of the command in 32-bit words.
+ * @acpm_chan_id: mailbox channel identifier.
+ * @response:	boolean flag indicating whether the kernel expects the ACPM
+ *              firmware to send a reply to this specific command.
+ */
+static void acpm_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdcnt,
+			  unsigned int acpm_chan_id, bool response)
+{
+	xfer->acpm_chan_id = acpm_chan_id;
+	xfer->txcnt = cmdcnt;
+	xfer->txd = cmd;
+
+	if (response) {
+		xfer->rxcnt = cmdcnt;
+		xfer->rxd = cmd;
+	} else {
+		xfer->rxcnt = 0;
+		xfer->rxd = NULL;
+	}
+}
+
 /**
  * acpm_chan_shmem_get_params() - get channel parameters and addresses of the
  * TX/RX queues.
diff --git a/drivers/firmware/samsung/exynos-acpm.h b/drivers/firmware/samsung/exynos-acpm.h
index 5df8354dc96c..708f6b0102ac 100644
--- a/drivers/firmware/samsung/exynos-acpm.h
+++ b/drivers/firmware/samsung/exynos-acpm.h
@@ -17,6 +17,8 @@ struct acpm_xfer {
 
 struct acpm_handle;
 
+void acpm_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdcnt,
+		   unsigned int acpm_chan_id, bool response);
 int acpm_do_xfer(struct acpm_handle *handle,
 		 const struct acpm_xfer *xfer);
 

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 03/11] firmware: samsung: acpm: Annotate rx_data->cmd with __counted_by_ptr

[Tudor Ambarus]

Rename the `n_cmd` member of `struct acpm_rx_data` to `cmdcnt` to
maintain consistent nomenclature across the driver (aligning with
`txcnt`, `rxcnt`, and transfer helpers).

With the member renamed, annotate the dynamically allocated `cmd`
pointer with the `__counted_by_ptr(cmdcnt)` macro to improve runtime
bounds checking.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/firmware/samsung/exynos-acpm.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index c4aca61a63e4..e5c85d769d0a 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -103,12 +103,12 @@ struct acpm_queue {
  * struct acpm_rx_data - RX queue data.
  *
  * @cmd:	pointer to where the data shall be saved.
- * @n_cmd:	number of 32-bit commands.
+ * @cmdcnt:	allocated capacity of the @cmd buffer in 32-bit words.
  * @rxcnt:	expected length of the response in 32-bit words.
  */
 struct acpm_rx_data {
-	u32 *cmd;
-	size_t n_cmd;
+	u32 *cmd __counted_by_ptr(cmdcnt);
+	size_t cmdcnt;
 	size_t rxcnt;
 };
 
@@ -384,7 +384,7 @@ static void acpm_prepare_xfer(struct acpm_chan *achan,
 
 	/* Clear data for upcoming responses */
 	rx_data = &achan->rx_data[achan->seqnum - 1];
-	memset(rx_data->cmd, 0, sizeof(*rx_data->cmd) * rx_data->n_cmd);
+	memset(rx_data->cmd, 0, sizeof(*rx_data->cmd) * rx_data->cmdcnt);
 	/* zero means no response expected */
 	rx_data->rxcnt = xfer->rxcnt;
 
@@ -537,19 +537,19 @@ static int acpm_achan_alloc_cmds(struct acpm_chan *achan)
 {
 	struct device *dev = achan->acpm->dev;
 	struct acpm_rx_data *rx_data;
-	size_t cmd_size, n_cmd;
+	size_t cmd_size, cmdcnt;
 	int i;
 
 	if (achan->mlen == 0)
 		return 0;
 
 	cmd_size = sizeof(*(achan->rx_data[0].cmd));
-	n_cmd = DIV_ROUND_UP_ULL(achan->mlen, cmd_size);
+	cmdcnt = DIV_ROUND_UP_ULL(achan->mlen, cmd_size);
 
 	for (i = 0; i < ACPM_SEQNUM_MAX; i++) {
 		rx_data = &achan->rx_data[i];
-		rx_data->n_cmd = n_cmd;
-		rx_data->cmd = devm_kcalloc(dev, n_cmd, cmd_size, GFP_KERNEL);
+		rx_data->cmdcnt = cmdcnt;
+		rx_data->cmd = devm_kcalloc(dev, cmdcnt, cmd_size, GFP_KERNEL);
 		if (!rx_data->cmd)
 			return -ENOMEM;
 	}

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 04/11] firmware: samsung: acpm: Drop redundant _ops suffix in acpm_ops members

[Tudor Ambarus]

Rename the `dvfs_ops` and `pmic_ops` members of `struct acpm_ops` to
`dvfs` and `pmic` respectively.

Since these members are housed within the `acpm_ops` structure and
utilize the `acpm_*_ops` types, the `_ops` suffix on the variable names
creates unnecessary redundancy (e.g., `handle.ops.dvfs_ops`).

This cleanup removes the stuttering, leading to cleaner consumer code.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/clk/samsung/clk-acpm.c                        | 8 ++++----
 drivers/firmware/samsung/exynos-acpm.c                | 4 ++--
 drivers/mfd/sec-acpm.c                                | 6 +++---
 include/linux/firmware/samsung/exynos-acpm-protocol.h | 4 ++--
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/samsung/clk-acpm.c b/drivers/clk/samsung/clk-acpm.c
index d8944160793a..93667777094c 100644
--- a/drivers/clk/samsung/clk-acpm.c
+++ b/drivers/clk/samsung/clk-acpm.c
@@ -68,8 +68,8 @@ static unsigned long acpm_clk_recalc_rate(struct clk_hw *hw,
 {
 	struct acpm_clk *clk = to_acpm_clk(hw);
 
-	return clk->handle->ops.dvfs_ops.get_rate(clk->handle,
-					clk->mbox_chan_id, clk->id);
+	return clk->handle->ops.dvfs.get_rate(clk->handle, clk->mbox_chan_id,
+					      clk->id);
 }
 
 static int acpm_clk_determine_rate(struct clk_hw *hw,
@@ -89,8 +89,8 @@ static int acpm_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 {
 	struct acpm_clk *clk = to_acpm_clk(hw);
 
-	return clk->handle->ops.dvfs_ops.set_rate(clk->handle,
-					clk->mbox_chan_id, clk->id, rate);
+	return clk->handle->ops.dvfs.set_rate(clk->handle, clk->mbox_chan_id,
+					      clk->id, rate);
 }
 
 static const struct clk_ops acpm_clk_ops = {
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index e5c85d769d0a..a2cd54ee4589 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -627,8 +627,8 @@ static int acpm_channels_init(struct acpm_info *acpm)
  */
 static void acpm_setup_ops(struct acpm_info *acpm)
 {
-	struct acpm_dvfs_ops *dvfs_ops = &acpm->handle.ops.dvfs_ops;
-	struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic_ops;
+	struct acpm_dvfs_ops *dvfs_ops = &acpm->handle.ops.dvfs;
+	struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic;
 
 	dvfs_ops->set_rate = acpm_dvfs_set_rate;
 	dvfs_ops->get_rate = acpm_dvfs_get_rate;
diff --git a/drivers/mfd/sec-acpm.c b/drivers/mfd/sec-acpm.c
index 0e23b9d9f7ee..9e15b260b8df 100644
--- a/drivers/mfd/sec-acpm.c
+++ b/drivers/mfd/sec-acpm.c
@@ -391,7 +391,7 @@ static int sec_pmic_acpm_bus_write(void *context, const void *data,
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic_ops;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
 	size_t val_count = count - BITS_TO_BYTES(ACPM_ADDR_BITS);
 	const u8 *d = data;
 	const u8 *vals = &d[BITS_TO_BYTES(ACPM_ADDR_BITS)];
@@ -411,7 +411,7 @@ static int sec_pmic_acpm_bus_read(void *context, const void *reg_buf, size_t reg
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic_ops;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
 	const u8 *r = reg_buf;
 	u8 reg;
 
@@ -430,7 +430,7 @@ static int sec_pmic_acpm_bus_reg_update_bits(void *context, unsigned int reg, un
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic_ops;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
 
 	return pmic_ops->update_reg(acpm, ctx->shared->acpm_chan_id, ctx->type, reg & 0xff,
 				    ctx->shared->speedy_channel, val, mask);
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index d4db2796a6fb..b206efa62be6 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -36,8 +36,8 @@ struct acpm_pmic_ops {
 };
 
 struct acpm_ops {
-	struct acpm_dvfs_ops dvfs_ops;
-	struct acpm_pmic_ops pmic_ops;
+	struct acpm_dvfs_ops dvfs;
+	struct acpm_pmic_ops pmic;
 };
 
 /**

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 05/11] firmware: samsung: acpm: Make acpm_ops const and access via pointer

[Tudor Ambarus]

Replace the embedded `struct acpm_ops` inside `struct acpm_handle` with
a pointer to a `const struct acpm_ops`.

Previously, the operations structure was embedded directly within the
handle and populated dynamically at runtime via `acpm_setup_ops()`.
This resulted in mutable function pointers and unnecessary per-instance
memory overhead.

By defining `exynos_acpm_driver_ops` statically as a `const` structure,
the function pointers are now safely housed in the read-only `.rodata`
section. This improves security by preventing function pointer
overwrites, saves memory, and slightly reduces initialization overhead
in `acpm_probe()`.

Consequently, update all consumer drivers (clk, mfd) to access the
operations via the new pointer indirection (`->ops->`). Finally, fix
the previously empty kernel-doc description for the ops member to
reflect its new pointer nature.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/clk/samsung/clk-acpm.c                     |  8 ++---
 drivers/firmware/samsung/exynos-acpm.c             | 36 ++++++++++------------
 drivers/mfd/sec-acpm.c                             |  6 ++--
 .../linux/firmware/samsung/exynos-acpm-protocol.h  |  4 +--
 4 files changed, 25 insertions(+), 29 deletions(-)

diff --git a/drivers/clk/samsung/clk-acpm.c b/drivers/clk/samsung/clk-acpm.c
index 93667777094c..953ca8d5720a 100644
--- a/drivers/clk/samsung/clk-acpm.c
+++ b/drivers/clk/samsung/clk-acpm.c
@@ -68,8 +68,8 @@ static unsigned long acpm_clk_recalc_rate(struct clk_hw *hw,
 {
 	struct acpm_clk *clk = to_acpm_clk(hw);
 
-	return clk->handle->ops.dvfs.get_rate(clk->handle, clk->mbox_chan_id,
-					      clk->id);
+	return clk->handle->ops->dvfs.get_rate(clk->handle, clk->mbox_chan_id,
+					       clk->id);
 }
 
 static int acpm_clk_determine_rate(struct clk_hw *hw,
@@ -89,8 +89,8 @@ static int acpm_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 {
 	struct acpm_clk *clk = to_acpm_clk(hw);
 
-	return clk->handle->ops.dvfs.set_rate(clk->handle, clk->mbox_chan_id,
-					      clk->id, rate);
+	return clk->handle->ops->dvfs.set_rate(clk->handle, clk->mbox_chan_id,
+					       clk->id, rate);
 }
 
 static const struct clk_ops acpm_clk_ops = {
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index a2cd54ee4589..38f40fb67ea7 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -621,30 +621,26 @@ static int acpm_channels_init(struct acpm_info *acpm)
 	return 0;
 }
 
-/**
- * acpm_setup_ops() - setup the operations structures.
- * @acpm:	pointer to the driver data.
- */
-static void acpm_setup_ops(struct acpm_info *acpm)
-{
-	struct acpm_dvfs_ops *dvfs_ops = &acpm->handle.ops.dvfs;
-	struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic;
-
-	dvfs_ops->set_rate = acpm_dvfs_set_rate;
-	dvfs_ops->get_rate = acpm_dvfs_get_rate;
-
-	pmic_ops->read_reg = acpm_pmic_read_reg;
-	pmic_ops->bulk_read = acpm_pmic_bulk_read;
-	pmic_ops->write_reg = acpm_pmic_write_reg;
-	pmic_ops->bulk_write = acpm_pmic_bulk_write;
-	pmic_ops->update_reg = acpm_pmic_update_reg;
-}
-
 static void acpm_clk_pdev_unregister(void *data)
 {
 	platform_device_unregister(data);
 }
 
+static const struct acpm_ops exynos_acpm_driver_ops = {
+	.dvfs = {
+		.set_rate = acpm_dvfs_set_rate,
+		.get_rate = acpm_dvfs_get_rate,
+	},
+
+	.pmic = {
+		.read_reg = acpm_pmic_read_reg,
+		.bulk_read = acpm_pmic_bulk_read,
+		.write_reg = acpm_pmic_write_reg,
+		.bulk_write = acpm_pmic_bulk_write,
+		.update_reg = acpm_pmic_update_reg,
+	},
+};
+
 static int acpm_probe(struct platform_device *pdev)
 {
 	const struct acpm_match_data *match_data;
@@ -689,7 +685,7 @@ static int acpm_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to add mbox free action.\n");
 
-	acpm_setup_ops(acpm);
+	acpm->handle.ops = &exynos_acpm_driver_ops;
 
 	platform_set_drvdata(pdev, acpm);
 
diff --git a/drivers/mfd/sec-acpm.c b/drivers/mfd/sec-acpm.c
index 9e15b260b8df..3397d13d3b7f 100644
--- a/drivers/mfd/sec-acpm.c
+++ b/drivers/mfd/sec-acpm.c
@@ -391,7 +391,7 @@ static int sec_pmic_acpm_bus_write(void *context, const void *data,
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic;
 	size_t val_count = count - BITS_TO_BYTES(ACPM_ADDR_BITS);
 	const u8 *d = data;
 	const u8 *vals = &d[BITS_TO_BYTES(ACPM_ADDR_BITS)];
@@ -411,7 +411,7 @@ static int sec_pmic_acpm_bus_read(void *context, const void *reg_buf, size_t reg
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic;
 	const u8 *r = reg_buf;
 	u8 reg;
 
@@ -430,7 +430,7 @@ static int sec_pmic_acpm_bus_reg_update_bits(void *context, unsigned int reg, un
 {
 	struct sec_pmic_acpm_bus_context *ctx = context;
 	struct acpm_handle *acpm = ctx->shared->acpm;
-	const struct acpm_pmic_ops *pmic_ops = &acpm->ops.pmic;
+	const struct acpm_pmic_ops *pmic_ops = &acpm->ops->pmic;
 
 	return pmic_ops->update_reg(acpm, ctx->shared->acpm_chan_id, ctx->type, reg & 0xff,
 				    ctx->shared->speedy_channel, val, mask);
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index b206efa62be6..fbf1829b33db 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -42,10 +42,10 @@ struct acpm_ops {
 
 /**
  * struct acpm_handle - Reference to an initialized protocol instance
- * @ops:
+ * @ops:	pointer to the constant ACPM protocol operations.
  */
 struct acpm_handle {
-	struct acpm_ops ops;
+	const struct acpm_ops *ops;
 };
 
 struct device;

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 06/11] firmware: samsung: acpm: Add TMU protocol support

[Tudor Ambarus]

The Thermal Management Unit (TMU) on the Google GS101 SoC is managed
through a hybrid model shared between the kernel and the Alive Clock
and Power Manager (ACPM) firmware.

Add the protocol helpers required to communicate with the ACPM for
thermal operations, including initialization, threshold configuration,
temperature reading, and system suspend/resume handshakes.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
---
 drivers/firmware/samsung/Makefile                  |   1 +
 drivers/firmware/samsung/exynos-acpm-tmu.c         | 240 +++++++++++++++++++++
 drivers/firmware/samsung/exynos-acpm-tmu.h         |  28 +++
 drivers/firmware/samsung/exynos-acpm.c             |  12 ++
 .../linux/firmware/samsung/exynos-acpm-protocol.h  |  18 ++
 5 files changed, 299 insertions(+)

diff --git a/drivers/firmware/samsung/Makefile b/drivers/firmware/samsung/Makefile
index 80d4f89b33a9..5a6f72bececf 100644
--- a/drivers/firmware/samsung/Makefile
+++ b/drivers/firmware/samsung/Makefile
@@ -3,4 +3,5 @@
 acpm-protocol-objs			:= exynos-acpm.o
 acpm-protocol-objs			+= exynos-acpm-pmic.o
 acpm-protocol-objs			+= exynos-acpm-dvfs.o
+acpm-protocol-objs			+= exynos-acpm-tmu.o
 obj-$(CONFIG_EXYNOS_ACPM_PROTOCOL)	+= acpm-protocol.o
diff --git a/drivers/firmware/samsung/exynos-acpm-tmu.c b/drivers/firmware/samsung/exynos-acpm-tmu.c
new file mode 100644
index 000000000000..7d9b75be032c
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-tmu.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2026 Linaro Ltd.
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/ktime.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include "exynos-acpm.h"
+#include "exynos-acpm-tmu.h"
+
+/* IPC Request Types */
+#define ACPM_TMU_INIT		0x01
+#define ACPM_TMU_READ_TEMP	0x02
+#define ACPM_TMU_SUSPEND	0x04
+#define ACPM_TMU_RESUME		0x10
+#define ACPM_TMU_THRESHOLD	0x11
+#define ACPM_TMU_INTEN		0x12
+#define ACPM_TMU_CONTROL	0x13
+#define ACPM_TMU_IRQ_CLEAR	0x14
+
+#define ACPM_TMU_TX_DATA_LEN	8
+#define ACPM_TMU_RX_DATA_LEN	7
+
+struct acpm_tmu_tx {
+	u16 ctx;
+	u16 fw_use;
+	u8 type;
+	u8 rsvd0;
+	u8 tzid;
+	u8 rsvd1;
+	u8 data[ACPM_TMU_TX_DATA_LEN];
+} __packed;
+
+struct acpm_tmu_rx {
+	u16 ctx;
+	u16 fw_use;
+	u8 type;
+	s8 ret;
+	u8 tzid;
+	s8 temp;
+	u8 rsvd;
+	u8 data[ACPM_TMU_RX_DATA_LEN];
+} __packed;
+
+union acpm_tmu_msg {
+	u32 data[4];
+	struct acpm_tmu_tx tx;
+	struct acpm_tmu_rx rx;
+};
+
+static int acpm_tmu_to_linux_err(s8 fw_err)
+{
+	/*
+	 * ACPM_TMU_INIT uses BIT(0) and BIT(1) of msg.rx.ret to flag APM
+	 * capabilities. Treat zero and all positive values as success.
+	 */
+	if (fw_err >= 0)
+		return 0;
+
+	if (fw_err == -1)
+		return -EACCES;
+
+	return -EIO;
+}
+
+int acpm_tmu_init(struct acpm_handle *handle, unsigned int acpm_chan_id)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_INIT;
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_read_temp(struct acpm_handle *handle, unsigned int acpm_chan_id,
+		       u8 tz, int *temp)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_READ_TEMP;
+	msg.tx.tzid = tz;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	ret = acpm_tmu_to_linux_err(msg.rx.ret);
+	if (ret)
+		return ret;
+
+	*temp = msg.rx.temp;
+
+	return 0;
+}
+
+int acpm_tmu_set_threshold(struct acpm_handle *handle,
+			   unsigned int acpm_chan_id, u8 tz,
+			   const u8 temperature[8], size_t tlen)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int i, ret;
+
+	if (tlen > ACPM_TMU_TX_DATA_LEN)
+		return -EINVAL;
+
+	msg.tx.type = ACPM_TMU_THRESHOLD;
+	msg.tx.tzid = tz;
+
+	for (i = 0; i < tlen; i++)
+		msg.tx.data[i] = temperature[i];
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_set_interrupt_enable(struct acpm_handle *handle,
+				  unsigned int acpm_chan_id, u8 tz, u8 inten)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_INTEN;
+	msg.tx.tzid = tz;
+	msg.tx.data[0] = inten;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_tz_control(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			u8 tz, bool enable)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_CONTROL;
+	msg.tx.tzid = tz;
+	msg.tx.data[0] = enable ? 1 : 0;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_clear_tz_irq(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			  u8 tz)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_IRQ_CLEAR;
+	msg.tx.tzid = tz;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_suspend(struct acpm_handle *handle, unsigned int acpm_chan_id)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_SUSPEND;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
+
+int acpm_tmu_resume(struct acpm_handle *handle, unsigned int acpm_chan_id)
+{
+	union acpm_tmu_msg msg = {0};
+	struct acpm_xfer xfer;
+	int ret;
+
+	msg.tx.type = ACPM_TMU_RESUME;
+
+	acpm_set_xfer(&xfer, msg.data, ARRAY_SIZE(msg.data), acpm_chan_id,
+		      true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_to_linux_err(msg.rx.ret);
+}
diff --git a/drivers/firmware/samsung/exynos-acpm-tmu.h b/drivers/firmware/samsung/exynos-acpm-tmu.h
new file mode 100644
index 000000000000..8b89f29fda67
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-tmu.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2026 Linaro Ltd.
+ */
+#ifndef __EXYNOS_ACPM_TMU_H__
+#define __EXYNOS_ACPM_TMU_H__
+
+#include <linux/types.h>
+
+struct acpm_handle;
+
+int acpm_tmu_init(struct acpm_handle *handle, unsigned int acpm_chan_id);
+int acpm_tmu_read_temp(struct acpm_handle *handle, unsigned int acpm_chan_id,
+		       u8 tz, int *temp);
+int acpm_tmu_set_threshold(struct acpm_handle *handle,
+			   unsigned int acpm_chan_id, u8 tz,
+			   const u8 temperature[8], size_t tlen);
+int acpm_tmu_set_interrupt_enable(struct acpm_handle *handle,
+				  unsigned int acpm_chan_id, u8 tz, u8 inten);
+int acpm_tmu_tz_control(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			u8 tz, bool enable);
+int acpm_tmu_clear_tz_irq(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			  u8 tz);
+int acpm_tmu_suspend(struct acpm_handle *handle, unsigned int acpm_chan_id);
+int acpm_tmu_resume(struct acpm_handle *handle, unsigned int acpm_chan_id);
+#endif /* __EXYNOS_ACPM_TMU_H__ */
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index 38f40fb67ea7..655b80fc635f 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -31,6 +31,7 @@
 #include "exynos-acpm.h"
 #include "exynos-acpm-dvfs.h"
 #include "exynos-acpm-pmic.h"
+#include "exynos-acpm-tmu.h"
 
 #define ACPM_PROTOCOL_SEQNUM		GENMASK(21, 16)
 
@@ -639,6 +640,17 @@ static const struct acpm_ops exynos_acpm_driver_ops = {
 		.bulk_write = acpm_pmic_bulk_write,
 		.update_reg = acpm_pmic_update_reg,
 	},
+
+	.tmu = {
+		.init = acpm_tmu_init,
+		.read_temp = acpm_tmu_read_temp,
+		.set_threshold = acpm_tmu_set_threshold,
+		.set_interrupt_enable = acpm_tmu_set_interrupt_enable,
+		.tz_control = acpm_tmu_tz_control,
+		.clear_tz_irq = acpm_tmu_clear_tz_irq,
+		.suspend = acpm_tmu_suspend,
+		.resume = acpm_tmu_resume,
+	},
 };
 
 static int acpm_probe(struct platform_device *pdev)
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index fbf1829b33db..08d9f5c95701 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -35,9 +35,27 @@ struct acpm_pmic_ops {
 			  u8 type, u8 reg, u8 chan, u8 value, u8 mask);
 };
 
+struct acpm_tmu_ops {
+	int (*init)(struct acpm_handle *handle, unsigned int acpm_chan_id);
+	int (*read_temp)(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			 u8 tz, int *temp);
+	int (*set_threshold)(struct acpm_handle *handle,
+			     unsigned int acpm_chan_id, u8 tz,
+			     const u8 temperature[8], size_t tlen);
+	int (*set_interrupt_enable)(struct acpm_handle *handle,
+				    unsigned int acpm_chan_id, u8 tz, u8 inten);
+	int (*tz_control)(struct acpm_handle *handle, unsigned int acpm_chan_id,
+			  u8 tz, bool enable);
+	int (*clear_tz_irq)(struct acpm_handle *handle,
+			    unsigned int acpm_chan_id, u8 tz);
+	int (*suspend)(struct acpm_handle *handle, unsigned int acpm_chan_id);
+	int (*resume)(struct acpm_handle *handle, unsigned int acpm_chan_id);
+};
+
 struct acpm_ops {
 	struct acpm_dvfs_ops dvfs;
 	struct acpm_pmic_ops pmic;
+	struct acpm_tmu_ops tmu;
 };
 
 /**

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 07/11] firmware: samsung: acpm: Add devm_acpm_get_by_phandle helper

[Tudor Ambarus]

Introduce devm_acpm_get_by_phandle() to standardize how consumer
drivers acquire a handle to the ACPM IPC interface. Enforce the
use of the "samsung,acpm-ipc" property name across the SoC and
simplify the boilerplate code in client drivers.

The first consumer of this helper is the Exynos ACPM Thermal Management
Unit (TMU) driver. The TMU utilizes a hybrid management approach: direct
register access from the Application Processor (AP) is restricted to the
interrupt pending (INTPEND) registers for event identification.
High-level functional tasks, such as sensor initialization, threshold
programming, and temperature reads, are delegated to the ACPM firmware
via this IPC interface.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/firmware/samsung/exynos-acpm.c             | 23 ++++++++++++++++++++++
 .../linux/firmware/samsung/exynos-acpm-protocol.h  |  6 ++++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index 655b80fc635f..6dee461f5827 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -812,6 +812,29 @@ struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_acpm_get_by_node);
 
+/**
+ * devm_acpm_get_by_phandle - Resource managed lookup of the standardized
+ * "samsung,acpm-ipc" handle.
+ * @dev: consumer device
+ *
+ * Returns a pointer to the acpm_handle on success, or an ERR_PTR on failure.
+ */
+struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev)
+{
+	struct acpm_handle *handle;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "samsung,acpm-ipc", 0);
+	if (!np)
+		return ERR_PTR(-ENODEV);
+
+	handle = devm_acpm_get_by_node(dev, np);
+	of_node_put(np);
+
+	return handle;
+}
+EXPORT_SYMBOL_GPL(devm_acpm_get_by_phandle);
+
 static const struct acpm_match_data acpm_gs101 = {
 	.initdata_base = ACPM_GS101_INITDATA_BASE,
 	.acpm_clk_dev_name = "gs101-acpm-clk",
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index 08d9f5c95701..83cbd425b652 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -71,6 +71,7 @@ struct device;
 #if IS_ENABLED(CONFIG_EXYNOS_ACPM_PROTOCOL)
 struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 					  struct device_node *np);
+struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev);
 #else
 
 static inline struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
@@ -78,6 +79,11 @@ static inline struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev)
+{
+	return ERR_PTR(-ENODEV);
+}
 #endif
 
 #endif /* __EXYNOS_ACPM_PROTOCOL_H */

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 08/11] thermal: samsung: Add Exynos ACPM TMU driver GS101

[Tudor Ambarus]

Add driver for the Thermal Management Unit (TMU) managed via the Alive
Clock and Power Manager (ACPM), found on Samsung Exynos SoCs such as
Google GS101 (and Exynos850, autov920, etc.).

The TMU on utilizes a hybrid management model shared between the
Application Processor (AP) and the ACPM firmware. The driver maintains
direct memory-mapped access to the TMU interrupt pending registers to
identify thermal events, while delegating functional tasks - such as
sensor initialization, threshold configuration, and temperature
acquisition - to the ACPM firmware via the ACPM IPC protocol.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
---
 drivers/thermal/samsung/Kconfig    |  17 ++
 drivers/thermal/samsung/Makefile   |   2 +
 drivers/thermal/samsung/acpm-tmu.c | 547 +++++++++++++++++++++++++++++++++++++
 3 files changed, 566 insertions(+)

diff --git a/drivers/thermal/samsung/Kconfig b/drivers/thermal/samsung/Kconfig
index f4eff5a41a84..0d3ffbdc66f0 100644
--- a/drivers/thermal/samsung/Kconfig
+++ b/drivers/thermal/samsung/Kconfig
@@ -9,3 +9,20 @@ config EXYNOS_THERMAL
 	  the TMU, reports temperature and handles cooling action if defined.
 	  This driver uses the Exynos core thermal APIs and TMU configuration
 	  data from the supported SoCs.
+
+config EXYNOS_ACPM_THERMAL
+	tristate "Exynos ACPM thermal management unit driver"
+	depends on THERMAL_OF
+	depends on EXYNOS_ACPM_PROTOCOL || (COMPILE_TEST && !EXYNOS_ACPM_PROTOCOL)
+	help
+	  Support for the Thermal Management Unit (TMU) on Samsung Exynos SoCs
+	  (such as Google GS101 and Exynos850).
+
+	  The TMU on these platforms is managed through a hybrid architecture.
+	  This driver handles direct register access for thermal interrupt status
+	  monitoring and communicates with the Alive Clock and Power Manager
+	  (ACPM) firmware via the ACPM IPC protocol for functional sensor control
+	  and configuration.
+
+	  Select this if you want to monitor device temperature and enable
+	  thermal mitigation on Samsung Exynos ACPM based devices.
diff --git a/drivers/thermal/samsung/Makefile b/drivers/thermal/samsung/Makefile
index f139407150d2..daed80647c34 100644
--- a/drivers/thermal/samsung/Makefile
+++ b/drivers/thermal/samsung/Makefile
@@ -4,3 +4,5 @@
 #
 obj-$(CONFIG_EXYNOS_THERMAL)			+= exynos_thermal.o
 exynos_thermal-y				:= exynos_tmu.o
+obj-$(CONFIG_EXYNOS_ACPM_THERMAL)		+= exynos_acpm_thermal.o
+exynos_acpm_thermal-y				:= acpm-tmu.o
diff --git a/drivers/thermal/samsung/acpm-tmu.c b/drivers/thermal/samsung/acpm-tmu.c
new file mode 100644
index 000000000000..d4e42b23c0c1
--- /dev/null
+++ b/drivers/thermal/samsung/acpm-tmu.c
@@ -0,0 +1,547 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2019 Samsung Electronics Co., Ltd.
+ * Copyright 2025 Google LLC.
+ * Copyright 2026 Linaro Ltd.
+ */
+
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/device/devres.h>
+#include <linux/err.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/interrupt.h>
+#include <linux/minmax.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+#include <linux/units.h>
+
+#include "../thermal_hwmon.h"
+
+#define EXYNOS_TMU_SENSOR(i)		BIT(i)
+#define EXYNOS_TMU_SENSORS_MAX_COUNT	16
+
+#define GS101_CPUCL2_SENSOR_MASK (EXYNOS_TMU_SENSOR(0) |	\
+				  EXYNOS_TMU_SENSOR(6) |	\
+				  EXYNOS_TMU_SENSOR(7) |	\
+				  EXYNOS_TMU_SENSOR(8) |	\
+				  EXYNOS_TMU_SENSOR(9))
+#define GS101_CPUCL1_SENSOR_MASK (EXYNOS_TMU_SENSOR(4) |	\
+				  EXYNOS_TMU_SENSOR(5))
+#define GS101_CPUCL0_SENSOR_MASK (EXYNOS_TMU_SENSOR(1) |	\
+				  EXYNOS_TMU_SENSOR(2))
+
+#define GS101_REG_INTPEND(i)		((i) * 0x50 + 0xf8)
+
+enum {
+	P0_INTPEND,
+	P1_INTPEND,
+	P2_INTPEND,
+	P3_INTPEND,
+	P4_INTPEND,
+	P5_INTPEND,
+	P6_INTPEND,
+	P7_INTPEND,
+	P8_INTPEND,
+	P9_INTPEND,
+	P10_INTPEND,
+	P11_INTPEND,
+	P12_INTPEND,
+	P13_INTPEND,
+	P14_INTPEND,
+	P15_INTPEND,
+	REG_INTPEND_COUNT,
+};
+
+struct acpm_tmu_sensor_group {
+	u16 mask;
+	u8 id;
+};
+
+struct acpm_tmu_sensor {
+	const struct acpm_tmu_sensor_group *group;
+	struct thermal_zone_device *tzd;
+	struct acpm_tmu_priv *priv;
+	struct mutex lock; /* protects sensor state */
+	bool enabled;
+};
+
+struct acpm_tmu_priv {
+	struct regmap_field *regmap_fields[REG_INTPEND_COUNT];
+	struct acpm_handle *handle;
+	struct device *dev;
+	struct clk *clk;
+	unsigned int mbox_chan_id;
+	unsigned int num_sensors;
+	int irq;
+	struct acpm_tmu_sensor sensors[] __counted_by(num_sensors);
+};
+
+struct acpm_tmu_driver_data {
+	const struct reg_field *reg_fields;
+	const struct acpm_tmu_sensor_group *sensor_groups;
+	unsigned int num_sensor_groups;
+	unsigned int mbox_chan_id;
+};
+
+#define ACPM_TMU_SENSOR_GROUP(_mask, _id)		\
+	{					\
+		.mask	= _mask,		\
+		.id	= _id,			\
+	}
+
+static const struct acpm_tmu_sensor_group gs101_sensor_groups[] = {
+	ACPM_TMU_SENSOR_GROUP(GS101_CPUCL2_SENSOR_MASK, 0),
+	ACPM_TMU_SENSOR_GROUP(GS101_CPUCL1_SENSOR_MASK, 1),
+	ACPM_TMU_SENSOR_GROUP(GS101_CPUCL0_SENSOR_MASK, 2),
+};
+
+static const struct reg_field gs101_reg_fields[REG_INTPEND_COUNT] = {
+	[P0_INTPEND] = REG_FIELD(GS101_REG_INTPEND(0), 0, 31),
+	[P1_INTPEND] = REG_FIELD(GS101_REG_INTPEND(1), 0, 31),
+	[P2_INTPEND] = REG_FIELD(GS101_REG_INTPEND(2), 0, 31),
+	[P3_INTPEND] = REG_FIELD(GS101_REG_INTPEND(3), 0, 31),
+	[P4_INTPEND] = REG_FIELD(GS101_REG_INTPEND(4), 0, 31),
+	[P5_INTPEND] = REG_FIELD(GS101_REG_INTPEND(5), 0, 31),
+	[P6_INTPEND] = REG_FIELD(GS101_REG_INTPEND(6), 0, 31),
+	[P7_INTPEND] = REG_FIELD(GS101_REG_INTPEND(7), 0, 31),
+	[P8_INTPEND] = REG_FIELD(GS101_REG_INTPEND(8), 0, 31),
+	[P9_INTPEND] = REG_FIELD(GS101_REG_INTPEND(9), 0, 31),
+	[P10_INTPEND] = REG_FIELD(GS101_REG_INTPEND(10), 0, 31),
+	[P11_INTPEND] = REG_FIELD(GS101_REG_INTPEND(11), 0, 31),
+	[P12_INTPEND] = REG_FIELD(GS101_REG_INTPEND(12), 0, 31),
+	[P13_INTPEND] = REG_FIELD(GS101_REG_INTPEND(13), 0, 31),
+	[P14_INTPEND] = REG_FIELD(GS101_REG_INTPEND(14), 0, 31),
+	[P15_INTPEND] = REG_FIELD(GS101_REG_INTPEND(15), 0, 31),
+};
+
+static const struct regmap_config gs101_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.use_relaxed_mmio = true,
+	.max_register = GS101_REG_INTPEND(15),
+};
+
+static const struct acpm_tmu_driver_data acpm_tmu_gs101 = {
+	.reg_fields = gs101_reg_fields,
+	.sensor_groups = gs101_sensor_groups,
+	.num_sensor_groups = ARRAY_SIZE(gs101_sensor_groups),
+	.mbox_chan_id = 9,
+};
+
+static int acpm_tmu_op_tz_control(struct acpm_tmu_sensor *sensor, bool on)
+{
+	struct acpm_tmu_priv *priv = sensor->priv;
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	int ret;
+
+	ret = ops->tz_control(handle, priv->mbox_chan_id, sensor->group->id,
+			      on);
+	if (ret)
+		return ret;
+
+	sensor->enabled = on;
+
+	return 0;
+}
+
+static int acpm_tmu_control(struct acpm_tmu_priv *priv, bool on)
+{
+	struct device *dev = priv->dev;
+	int i, ret;
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < priv->num_sensors; i++) {
+		struct acpm_tmu_sensor *sensor = &priv->sensors[i];
+
+		/* Skip sensors that weren't found in DT */
+		if (!sensor->tzd)
+			continue;
+
+		mutex_lock(&sensor->lock);
+		ret = acpm_tmu_op_tz_control(sensor, on);
+		mutex_unlock(&sensor->lock);
+		if (ret)
+			break;
+	}
+
+	pm_runtime_put_autosuspend(dev);
+	return ret;
+}
+
+static int acpm_tmu_get_temp(struct thermal_zone_device *tz, int *temp)
+{
+	struct acpm_tmu_sensor *sensor = thermal_zone_device_priv(tz);
+	struct acpm_tmu_priv *priv = sensor->priv;
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	struct device *dev = priv->dev;
+	int acpm_temp, ret;
+
+	if (!sensor->enabled)
+		return -EAGAIN;
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0)
+		return ret;
+
+	scoped_guard(mutex, &sensor->lock) {
+		ret = ops->read_temp(handle, priv->mbox_chan_id,
+				     sensor->group->id, &acpm_temp);
+	}
+
+	pm_runtime_put_autosuspend(dev);
+
+	if (ret)
+		return ret;
+
+	*temp = acpm_temp * MILLIDEGREE_PER_DEGREE;
+
+	return 0;
+}
+
+static int acpm_tmu_update_thresholds(struct acpm_tmu_sensor *sensor,
+				      u8 thresholds[2], u8 inten)
+{
+	struct acpm_tmu_priv *priv = sensor->priv;
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	unsigned int mbox_chan_id = priv->mbox_chan_id;
+	u8 acpm_sensor_id = sensor->group->id;
+	bool was_enabled = sensor->enabled;
+	int ret;
+
+	guard(mutex)(&sensor->lock);
+
+	if (was_enabled) {
+		ret = acpm_tmu_op_tz_control(sensor, false);
+		if (ret)
+			return ret;
+	}
+
+	ret = ops->set_threshold(handle, mbox_chan_id, acpm_sensor_id,
+				 thresholds, 2);
+	if (ret)
+		return ret;
+
+	ret = ops->set_interrupt_enable(handle, mbox_chan_id, acpm_sensor_id,
+					inten);
+	if (ret)
+		return ret;
+
+	/* Restore based on cached state. */
+	if (was_enabled)
+		ret = acpm_tmu_op_tz_control(sensor, true);
+
+	return ret;
+}
+
+static int acpm_tmu_set_trips(struct thermal_zone_device *tz, int low, int high)
+{
+	struct acpm_tmu_sensor *sensor = thermal_zone_device_priv(tz);
+	struct acpm_tmu_priv *priv = sensor->priv;
+	struct device *dev = priv->dev;
+	u8 thresholds[2] = {};
+	u8 inten = 0;
+	int ret;
+
+	/* If a valid lower bound exists, set the threshold and enable its interrupt */
+	if (low > -INT_MAX) {
+		thresholds[0] = clamp_val(low / MILLIDEGREE_PER_DEGREE, 0, 255);
+		inten |= BIT(0);
+	}
+
+	/* If a valid upper bound exists, set the threshold and enable its interrupt */
+	if (high < INT_MAX) {
+		thresholds[1] = clamp_val(high / MILLIDEGREE_PER_DEGREE, 0, 255);
+		inten |= BIT(1);
+	}
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret)
+		return ret;
+
+	ret = acpm_tmu_update_thresholds(sensor, thresholds, inten);
+
+	pm_runtime_put_autosuspend(dev);
+
+	return ret;
+}
+
+static const struct thermal_zone_device_ops acpm_tmu_sensor_ops = {
+	.get_temp = acpm_tmu_get_temp,
+	.set_trips = acpm_tmu_set_trips,
+};
+
+static int acpm_tmu_has_pending_irq(struct acpm_tmu_sensor *sensor,
+				    bool *pending_irq)
+{
+	struct acpm_tmu_priv *priv = sensor->priv;
+	unsigned long mask = sensor->group->mask;
+	int i, ret;
+	u32 val;
+
+	guard(mutex)(&sensor->lock);
+
+	for_each_set_bit(i, &mask, EXYNOS_TMU_SENSORS_MAX_COUNT) {
+		ret = regmap_field_read(priv->regmap_fields[i], &val);
+		if (ret)
+			return ret;
+
+		if (val) {
+			*pending_irq = true;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static irqreturn_t acpm_tmu_thread_fn(int irq, void *id)
+{
+	struct acpm_tmu_priv *priv = id;
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	struct device *dev = priv->dev;
+	int i, ret;
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret) {
+		dev_err(dev, "Failed to resume: %d\n", ret);
+		return IRQ_NONE;
+	}
+
+	for (i = 0; i < priv->num_sensors; i++) {
+		struct acpm_tmu_sensor *sensor = &priv->sensors[i];
+		bool pending_irq = false;
+
+		if (!sensor->tzd)
+			continue;
+
+		ret = acpm_tmu_has_pending_irq(sensor, &pending_irq);
+		if (ret || !pending_irq)
+			continue;
+
+		thermal_zone_device_update(sensor->tzd,
+					   THERMAL_EVENT_UNSPECIFIED);
+
+		scoped_guard(mutex, &sensor->lock) {
+			ret = ops->clear_tz_irq(handle, priv->mbox_chan_id,
+						sensor->group->id);
+			if (ret)
+				dev_err(priv->dev, "Sensor %d: failed to clear IRQ (%d)\n",
+					i, ret);
+		}
+	}
+
+	pm_runtime_put_autosuspend(dev);
+
+	return IRQ_HANDLED;
+}
+
+static const struct of_device_id acpm_tmu_match[] = {
+	{ .compatible = "google,gs101-tmu-top" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, acpm_tmu_match);
+
+static int acpm_tmu_probe(struct platform_device *pdev)
+{
+	const struct acpm_tmu_driver_data *data = &acpm_tmu_gs101;
+	struct acpm_handle *acpm_handle;
+	struct device *dev = &pdev->dev;
+	struct acpm_tmu_priv *priv;
+	struct regmap *regmap;
+	void __iomem *base;
+	int i, ret;
+
+	acpm_handle = devm_acpm_get_by_phandle(dev);
+	if (IS_ERR(acpm_handle))
+		return dev_err_probe(dev, PTR_ERR(acpm_handle),
+				     "Failed to get ACPM handle\n");
+
+	priv = devm_kzalloc(dev,
+			    struct_size(priv, sensors, data->num_sensor_groups),
+			    GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+	priv->handle = acpm_handle;
+	priv->mbox_chan_id = data->mbox_chan_id;
+	priv->num_sensors = data->num_sensor_groups;
+
+	platform_set_drvdata(pdev, priv);
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return dev_err_probe(dev, PTR_ERR(base), "Failed to ioremap resource\n");
+
+	regmap = devm_regmap_init_mmio(dev, base, &gs101_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap), "Failed to init regmap\n");
+
+	ret = devm_regmap_field_bulk_alloc(dev, regmap, priv->regmap_fields,
+					   data->reg_fields, REG_INTPEND_COUNT);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Unable to map syscon registers\n");
+
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk))
+		return dev_err_probe(dev, PTR_ERR(priv->clk),
+				     "Failed to get the clock\n");
+
+	priv->irq = platform_get_irq(pdev, 0);
+	if (priv->irq < 0)
+		return dev_err_probe(dev, priv->irq, "Failed to get irq\n");
+
+	ret = devm_request_threaded_irq(dev, priv->irq, NULL,
+					acpm_tmu_thread_fn, IRQF_ONESHOT,
+					dev_name(dev), priv);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to request irq\n");
+
+	pm_runtime_set_autosuspend_delay(dev, 100);
+	pm_runtime_use_autosuspend(dev);
+
+	ret = devm_pm_runtime_enable(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable runtime PM\n");
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Failed to resume device\n");
+
+	ret = acpm_handle->ops->tmu.init(acpm_handle, priv->mbox_chan_id);
+	if (ret) {
+		ret = dev_err_probe(dev, ret, "Failed to init TMU\n");
+		goto err_pm_put;
+	}
+
+	for (i = 0; i < priv->num_sensors; i++) {
+		struct acpm_tmu_sensor *sensor = &priv->sensors[i];
+
+		mutex_init(&sensor->lock);
+		sensor->group = &data->sensor_groups[i];
+		sensor->priv = priv;
+
+		sensor->tzd = devm_thermal_of_zone_register(dev, i, sensor,
+							    &acpm_tmu_sensor_ops);
+		if (IS_ERR(sensor->tzd)) {
+			ret = PTR_ERR(sensor->tzd);
+			if (ret == -ENODEV) {
+				sensor->tzd = NULL;
+				dev_dbg(dev, "Sensor %d not used in DT, skipping\n", i);
+				continue;
+			}
+
+			ret = dev_err_probe(dev, ret, "Failed to register sensor %d\n", i);
+			goto err_pm_put;
+		}
+
+		ret = devm_thermal_add_hwmon_sysfs(dev, sensor->tzd);
+		if (ret)
+			dev_warn(dev, "Failed to add hwmon sysfs!\n");
+	}
+
+	ret = acpm_tmu_control(priv, true);
+	if (ret) {
+		ret = dev_err_probe(dev, ret, "Failed to enable TMU\n");
+		goto err_pm_put;
+	}
+
+	pm_runtime_put_autosuspend(dev);
+
+	return 0;
+
+err_pm_put:
+	pm_runtime_put_sync(dev);
+	return ret;
+}
+
+static void acpm_tmu_remove(struct platform_device *pdev)
+{
+	struct acpm_tmu_priv *priv = platform_get_drvdata(pdev);
+
+	/* Stop IRQ first to prevent race with thread_fn */
+	disable_irq(priv->irq);
+
+	acpm_tmu_control(priv, false);
+}
+
+static int acpm_tmu_suspend(struct device *dev)
+{
+	struct acpm_tmu_priv *priv = dev_get_drvdata(dev);
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	int ret;
+
+	ret = acpm_tmu_control(priv, false);
+	if (ret)
+		return ret;
+
+	/* APB clock not required for this specific msg */
+	return ops->suspend(handle, priv->mbox_chan_id);
+}
+
+static int acpm_tmu_resume(struct device *dev)
+{
+	struct acpm_tmu_priv *priv = dev_get_drvdata(dev);
+	struct acpm_handle *handle = priv->handle;
+	const struct acpm_tmu_ops *ops = &handle->ops->tmu;
+	int ret;
+
+	/* APB clock not required for this specific msg */
+	ret = ops->resume(handle, priv->mbox_chan_id);
+	if (ret)
+		return ret;
+
+	return acpm_tmu_control(priv, true);
+}
+
+static int acpm_tmu_runtime_suspend(struct device *dev)
+{
+	struct acpm_tmu_priv *priv = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static int acpm_tmu_runtime_resume(struct device *dev)
+{
+	struct acpm_tmu_priv *priv = dev_get_drvdata(dev);
+
+	return clk_prepare_enable(priv->clk);
+}
+
+static const struct dev_pm_ops acpm_tmu_pm_ops = {
+	SYSTEM_SLEEP_PM_OPS(acpm_tmu_suspend, acpm_tmu_resume)
+	RUNTIME_PM_OPS(acpm_tmu_runtime_suspend, acpm_tmu_runtime_resume, NULL)
+};
+
+static struct platform_driver acpm_tmu_driver = {
+	.driver = {
+		.name   = "gs-tmu",
+		.pm     = pm_ptr(&acpm_tmu_pm_ops),
+		.of_match_table = acpm_tmu_match,
+	},
+	.probe = acpm_tmu_probe,
+	.remove = acpm_tmu_remove,
+};
+module_platform_driver(acpm_tmu_driver);
+
+MODULE_AUTHOR("Tudor Ambarus <tudor.ambarus@linaro.org>");
+MODULE_DESCRIPTION("Samsung Exynos ACPM TMU Driver");
+MODULE_LICENSE("GPL");

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 09/11] MAINTAINERS: Add entry for Samsung Exynos ACPM thermal driver

[Tudor Ambarus]

Add a MAINTAINERS entry for the Samsung Exynos ACPM thermal driver.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index c9b7b6f9828e..759c05bd0004 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -23693,6 +23693,14 @@ F:	drivers/clk/samsung/clk-acpm.c
 F:	drivers/firmware/samsung/exynos-acpm*
 F:	include/linux/firmware/samsung/exynos-acpm-protocol.h
 
+SAMSUNG EXYNOS ACPM THERMAL DRIVER
+M:	Tudor Ambarus <tudor.ambarus@linaro.org>
+L:	linux-kernel@vger.kernel.org
+L:	linux-samsung-soc@vger.kernel.org
+S:	Supported
+F:	Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
+F:	drivers/thermal/samsung/acpm-tmu.c
+
 SAMSUNG EXYNOS MAILBOX DRIVER
 M:	Tudor Ambarus <tudor.ambarus@linaro.org>
 L:	linux-kernel@vger.kernel.org

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 10/11] arm64: dts: exynos: gs101: Add thermal management unit

[Tudor Ambarus]

Add the Thermal Management Unit (TMU) support for the Google GS101 SoC.

Describe the TMU using a consolidated SoC node that includes memory
resources for interrupt identification and a phandle to the ACPM IPC
interface for functional control.

Define thermal zones for the little, mid, and big CPU clusters, including
associated trip points and cooling-device maps to enable thermal
mitigation.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 arch/arm64/boot/dts/exynos/google/gs101-tmu.dtsi | 136 +++++++++++++++++++++++
 arch/arm64/boot/dts/exynos/google/gs101.dtsi     |  18 +++
 2 files changed, 154 insertions(+)

diff --git a/arch/arm64/boot/dts/exynos/google/gs101-tmu.dtsi b/arch/arm64/boot/dts/exynos/google/gs101-tmu.dtsi
new file mode 100644
index 000000000000..b27d1a539ec2
--- /dev/null
+++ b/arch/arm64/boot/dts/exynos/google/gs101-tmu.dtsi
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Google GS101 TMU configurations device tree source
+ *
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2026 Linaro Ltd.
+ */
+
+#include <dt-bindings/thermal/thermal.h>
+
+/ {
+	thermal-zones {
+		cpucl2-thermal {
+			polling-delay-passive = <0>;
+			polling-delay = <0>;
+			thermal-sensors = <&tmu_top 0>;
+
+			trips {
+				big_switch_on: big-switch-on {
+					temperature = <80000>;
+					hysteresis = <2000>;
+					type = "passive";
+				};
+
+				big_mitigate: big-mitigate {
+					temperature = <90000>;
+					hysteresis = <5000>;
+					type = "passive";
+				};
+
+				big_hot: big-hot {
+					temperature = <100000>;
+					hysteresis = <5000>;
+					type = "hot";
+				};
+
+				big_critical: big-critical {
+					temperature = <105000>;
+					hysteresis = <2000>;
+					type = "critical";
+				};
+			};
+
+			cooling-maps {
+				map0 {
+					trip = <&big_mitigate>;
+					cooling-device = <&cpu6 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu7 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
+		};
+
+		cpucl1-thermal {
+			polling-delay-passive = <0>;
+			polling-delay = <0>;
+			thermal-sensors = <&tmu_top 1>;
+
+			trips {
+				mid_switch_on: mid-switch-on {
+					temperature = <80000>;
+					hysteresis = <2000>;
+					type = "passive";
+				};
+
+				mid_mitigate: mid-mitigate {
+					temperature = <90000>;
+					hysteresis = <5000>;
+					type = "passive";
+				};
+
+				mid_hot: mid-hot {
+					temperature = <100000>;
+					hysteresis = <5000>;
+					type = "hot";
+				};
+
+				mid_critical: mid-critical {
+					temperature = <105000>;
+					hysteresis = <2000>;
+					type = "critical";
+				};
+			};
+
+			cooling-maps {
+				map0 {
+				     trip = <&mid_mitigate>;
+					cooling-device = <&cpu4 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu5 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			       };
+			};
+		};
+
+		cpucl0-thermal {
+			polling-delay-passive = <0>;
+			polling-delay = <0>;
+			thermal-sensors = <&tmu_top 2>;
+
+			trips {
+				little_switch_on: little-switch-on {
+					temperature = <80000>;
+					hysteresis = <2000>;
+					type = "passive";
+				};
+
+				little_mitigate: little-mitigate {
+					temperature = <90000>;
+					hysteresis = <5000>;
+					type = "passive";
+				};
+
+				little_hot: little-hot {
+					temperature = <100000>;
+					hysteresis = <5000>;
+					type = "hot";
+				};
+
+				little_critical: little-critical {
+					temperature = <105000>;
+					hysteresis = <2000>;
+					type = "critical";
+				};
+			};
+
+			cooling-maps {
+				map0 {
+					trip = <&little_mitigate>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
+		};
+	};
+};
diff --git a/arch/arm64/boot/dts/exynos/google/gs101.dtsi b/arch/arm64/boot/dts/exynos/google/gs101.dtsi
index d085f9fb0f62..4b8c7edaddb6 100644
--- a/arch/arm64/boot/dts/exynos/google/gs101.dtsi
+++ b/arch/arm64/boot/dts/exynos/google/gs101.dtsi
@@ -74,6 +74,7 @@ cpu0: cpu@0 {
 			compatible = "arm,cortex-a55";
 			reg = <0x0000>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL0>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&ananke_cpu_sleep>;
 			capacity-dmips-mhz = <250>;
@@ -86,6 +87,7 @@ cpu1: cpu@100 {
 			compatible = "arm,cortex-a55";
 			reg = <0x0100>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL0>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&ananke_cpu_sleep>;
 			capacity-dmips-mhz = <250>;
@@ -98,6 +100,7 @@ cpu2: cpu@200 {
 			compatible = "arm,cortex-a55";
 			reg = <0x0200>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL0>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&ananke_cpu_sleep>;
 			capacity-dmips-mhz = <250>;
@@ -110,6 +113,7 @@ cpu3: cpu@300 {
 			compatible = "arm,cortex-a55";
 			reg = <0x0300>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL0>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&ananke_cpu_sleep>;
 			capacity-dmips-mhz = <250>;
@@ -122,6 +126,7 @@ cpu4: cpu@400 {
 			compatible = "arm,cortex-a76";
 			reg = <0x0400>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL1>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&enyo_cpu_sleep>;
 			capacity-dmips-mhz = <620>;
@@ -134,6 +139,7 @@ cpu5: cpu@500 {
 			compatible = "arm,cortex-a76";
 			reg = <0x0500>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL1>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&enyo_cpu_sleep>;
 			capacity-dmips-mhz = <620>;
@@ -146,6 +152,7 @@ cpu6: cpu@600 {
 			compatible = "arm,cortex-x1";
 			reg = <0x0600>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL2>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&hera_cpu_sleep>;
 			capacity-dmips-mhz = <1024>;
@@ -158,6 +165,7 @@ cpu7: cpu@700 {
 			compatible = "arm,cortex-x1";
 			reg = <0x0700>;
 			clocks = <&acpm_ipc GS101_CLK_ACPM_DVFS_CPUCL2>;
+			#cooling-cells = <2>;
 			enable-method = "psci";
 			cpu-idle-states = <&hera_cpu_sleep>;
 			capacity-dmips-mhz = <1024>;
@@ -639,6 +647,15 @@ watchdog_cl1: watchdog@10070000 {
 			status = "disabled";
 		};
 
+		tmu_top: thermal-sensor@100a0000 {
+			compatible = "google,gs101-tmu-top";
+			reg = <0x100a0000 0x800>;
+			clocks = <&cmu_misc CLK_GOUT_MISC_TMU_TOP_PCLK>;
+			interrupts = <GIC_SPI 769 IRQ_TYPE_LEVEL_HIGH 0>;
+			samsung,acpm-ipc = <&acpm_ipc>;
+			#thermal-sensor-cells = <1>;
+		};
+
 		trng: rng@10141400 {
 			compatible = "google,gs101-trng",
 				     "samsung,exynos850-trng";
@@ -1861,3 +1878,4 @@ timer {
 };
 
 #include "gs101-pinctrl.dtsi"
+#include "gs101-tmu.dtsi"

-- 
2.54.0.545.g6539524ca2-goog

[PATCH v4 11/11] arm64: defconfig: enable Exynos ACPM thermal support

[Tudor Ambarus]

Enable the Exynos ACPM thermal driver (CONFIG_EXYNOS_ACPM_THERMAL)
to allow temperature monitoring and thermal management on Samsung
Exynos SoCs that use the Alive Clock and Power Manager (ACPM)
protocol.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 arch/arm64/configs/defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index d905a0777f93..3fe76a4c2633 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -793,6 +793,7 @@ CONFIG_BCM2711_THERMAL=m
 CONFIG_BCM2835_THERMAL=m
 CONFIG_BRCMSTB_THERMAL=m
 CONFIG_EXYNOS_THERMAL=y
+CONFIG_EXYNOS_ACPM_THERMAL=m
 CONFIG_TEGRA_SOCTHERM=m
 CONFIG_TEGRA_BPMP_THERMAL=m
 CONFIG_GENERIC_ADC_THERMAL=m

-- 
2.54.0.545.g6539524ca2-goog

Re: [PATCH v4 00/11] thermal: samsung: Add support for Google GS101 TMU

[Krzysztof Kozlowski]

On 23/04/2026 17:22, Tudor Ambarus wrote:
> Add support for the Thermal Management Unit (TMU) on the Google GS101
> SoC.
> 
> The GS101 TMU implementation utilizes a hybrid architecture where
> management is shared between the kernel and the Alive Clock and
> Power Manager (ACPM) firmware. This hybrid ACPM TMU architecture is 
> also present on other Samsung Exynos SoCs (e.g., AutoV920, Exynos850).
> 
> Dependencies
> ============
> - context dependency on the ACPM fixes sent at:
>   Link: https://lore.kernel.org/linux-samsung-soc/20260423-acpm-fixes-sashiko-reports-v1-0-2217b790925e@linaro.org/T/#t
> - cleanup and prep firmware patches 2, 3, 4, 5, 6, 7: required by the
>   thermal driver (patch 8).

Well, cleanup in one driver cannot be a dependency for other driver.

> - bindings (patch 1): required for DTS validation.
> - thermal driver patch 8: required by defconfig (patch 11) - logical
> dependency. 

Most of the patches should be taken before, which would leave you only
final new firmware interface as dependency. Creating such unnecessary
dependencies is not helping.

And the patchset even grew and will conflict with other firmware work,
so I will deal with firmware bits and I can provide them via stable tag
to thermal for the last patch.

Best regards,
Krzysztof

Re: [PATCH v4 02/11] firmware: samsung: acpm: Consolidate transfer initialization helper

[Krzysztof Kozlowski]

On 23/04/2026 17:22, Tudor Ambarus wrote:
>  	acpm_dvfs_init_get_rate_cmd(cmd, clk_id);
> -	acpm_dvfs_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
> +	acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, true);
>  
>  	ret = acpm_do_xfer(handle, &xfer);
>  	if (ret)
> diff --git a/drivers/firmware/samsung/exynos-acpm-pmic.c b/drivers/firmware/samsung/exynos-acpm-pmic.c
> index 0c50993cc9a8..f032f2c69685 100644
> --- a/drivers/firmware/samsung/exynos-acpm-pmic.c
> +++ b/drivers/firmware/samsung/exynos-acpm-pmic.c
> @@ -58,16 +58,6 @@ static inline u32 acpm_pmic_get_bulk(u32 data, unsigned int i)
>  	return (data >> (ACPM_PMIC_BULK_SHIFT * i)) & ACPM_PMIC_BULK_MASK;
>  }
>  
> -static void acpm_pmic_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdlen,
> -			       unsigned int acpm_chan_id)
> -{
> -	xfer->txd = cmd;
> -	xfer->rxd = cmd;
> -	xfer->txcnt = cmdlen;
> -	xfer->rxcnt = cmdlen;
> -	xfer->acpm_chan_id = acpm_chan_id;

The code is not equivalent. RX bits were always cleared. This should be
explained in the commit msg which would also provide a proof that you
actually analyzed if it has any impact.



Best regards,
Krzysztof