Merge tag 'samsung-drivers-firmware-clk-6.19' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux into clk-samsung

Pull Samsung clk driver updates from Krzysztof Kozlowski:

Extend Samsung ACPM (Alive Clock and Power Manager) firmware drivers:

- Add support for passing DVFS (Dynamic Voltage and Frequency) messages
to configure the clocks in ACPM device.
- Add Exynos ACPM clock driver, which exposes to Linux several clocks
handled by the ACPM (firmware)

* tag 'samsung-drivers-firmware-clk-6.19' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux:
firmware: exynos-acpm: add empty method to allow compile test
MAINTAINERS: add ACPM clock bindings and driver
clk: samsung: add Exynos ACPM clock driver
firmware: exynos-acpm: register ACPM clocks pdev
firmware: exynos-acpm: add DVFS protocol
dt-bindings: firmware: google,gs101-acpm-ipc: add ACPM clocks

Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml

···
   compatible:
     const: google,gs101-acpm-ipc
 
+  "#clock-cells":
+    const: 1
+    description:
+      Clocks that are variable and index based. These clocks don't provide
+      an entire range of values between the limits but only discrete points
+      within the range. The firmware also manages the voltage scaling
+      appropriately with the clock scaling. The argument is the ID of the
+      clock contained by the firmware messages.
+
   mboxes:
     maxItems: 1
 
···
 
 required:
   - compatible
+  - "#clock-cells"
   - mboxes
   - shmem
 
···
 
     power-management {
         compatible = "google,gs101-acpm-ipc";
+        #clock-cells = <1>;
         mboxes = <&ap2apm_mailbox>;
         shmem = <&apm_sram>;
 

MAINTAINERS

···
 F:	arch/arm64/boot/dts/exynos/google/
 F:	drivers/clk/samsung/clk-gs101.c
 F:	drivers/phy/samsung/phy-gs101-ufs.c
-F:	include/dt-bindings/clock/google,gs101.h
+F:	include/dt-bindings/clock/google,gs101*
 K:	[gG]oogle.?[tT]ensor
 
 GPD FAN DRIVER
···
 L:	[e-mail]
 S:	Supported
 F:	Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
+F:	drivers/clk/samsung/clk-acpm.c
 F:	drivers/firmware/samsung/exynos-acpm*
 F:	include/linux/firmware/samsung/exynos-acpm-protocol.h
 

drivers/clk/samsung/Kconfig

···
 	  status of the certains clocks from SoC, but it could also be tied to
 	  other devices as an input clock.
 
+config EXYNOS_ACPM_CLK
+	tristate "Clock driver controlled via ACPM interface"
+	depends on EXYNOS_ACPM_PROTOCOL || (COMPILE_TEST && !EXYNOS_ACPM_PROTOCOL)
+	help
+	  This driver provides support for clocks that are controlled by
+	  firmware that implements the ACPM interface.
+
+	  This driver uses the ACPM interface to interact with the firmware
+	  providing all the clock controlls.
+
 config TESLA_FSD_COMMON_CLK
 	bool "Tesla FSD clock controller support" if COMPILE_TEST
 	depends on COMMON_CLK_SAMSUNG

drivers/clk/samsung/Makefile

···
 obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-exynosautov9.o
 obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-exynosautov920.o
 obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-gs101.o
+obj-$(CONFIG_EXYNOS_ACPM_CLK)		+= clk-acpm.o
 obj-$(CONFIG_S3C64XX_COMMON_CLK)	+= clk-s3c64xx.o
 obj-$(CONFIG_S5PV210_COMMON_CLK)	+= clk-s5pv210.o clk-s5pv210-audss.o
 obj-$(CONFIG_TESLA_FSD_COMMON_CLK)	+= clk-fsd.o

drivers/clk/samsung/clk-acpm.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Samsung Exynos ACPM protocol based clock driver.
+ *
+ * Copyright 2025 Linaro Ltd.
+ */
+
+#include <linux/array_size.h>
+#include <linux/clk-provider.h>
+#include <linux/container_of.h>
+#include <linux/device/devres.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+struct acpm_clk {
+	u32 id;
+	struct clk_hw hw;
+	unsigned int mbox_chan_id;
+	const struct acpm_handle *handle;
+};
+
+struct acpm_clk_variant {
+	const char *name;
+};
+
+struct acpm_clk_driver_data {
+	const struct acpm_clk_variant *clks;
+	unsigned int nr_clks;
+	unsigned int mbox_chan_id;
+};
+
+#define to_acpm_clk(clk) container_of(clk, struct acpm_clk, hw)
+
+#define ACPM_CLK(cname)					\
+	{						\
+		.name		= cname,		\
+	}
+
+static const struct acpm_clk_variant gs101_acpm_clks[] = {
+	ACPM_CLK("mif"),
+	ACPM_CLK("int"),
+	ACPM_CLK("cpucl0"),
+	ACPM_CLK("cpucl1"),
+	ACPM_CLK("cpucl2"),
+	ACPM_CLK("g3d"),
+	ACPM_CLK("g3dl2"),
+	ACPM_CLK("tpu"),
+	ACPM_CLK("intcam"),
+	ACPM_CLK("tnr"),
+	ACPM_CLK("cam"),
+	ACPM_CLK("mfc"),
+	ACPM_CLK("disp"),
+	ACPM_CLK("bo"),
+};
+
+static const struct acpm_clk_driver_data acpm_clk_gs101 = {
+	.clks = gs101_acpm_clks,
+	.nr_clks = ARRAY_SIZE(gs101_acpm_clks),
+	.mbox_chan_id = 0,
+};
+
+static unsigned long acpm_clk_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	struct acpm_clk *clk = to_acpm_clk(hw);
+
+	return clk->handle->ops.dvfs_ops.get_rate(clk->handle,
+					clk->mbox_chan_id, clk->id);
+}
+
+static int acpm_clk_determine_rate(struct clk_hw *hw,
+				   struct clk_rate_request *req)
+{
+	/*
+	 * We can't figure out what rate it will be, so just return the
+	 * rate back to the caller. acpm_clk_recalc_rate() will be called
+	 * after the rate is set and we'll know what rate the clock is
+	 * running at then.
+	 */
+	return 0;
+}
+
+static int acpm_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+			     unsigned long parent_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);
+}
+
+static const struct clk_ops acpm_clk_ops = {
+	.recalc_rate = acpm_clk_recalc_rate,
+	.determine_rate = acpm_clk_determine_rate,
+	.set_rate = acpm_clk_set_rate,
+};
+
+static int acpm_clk_register(struct device *dev, struct acpm_clk *aclk,
+			     const char *name)
+{
+	struct clk_init_data init = {};
+
+	init.name = name;
+	init.ops = &acpm_clk_ops;
+	aclk->hw.init = &init;
+
+	return devm_clk_hw_register(dev, &aclk->hw);
+}
+
+static int acpm_clk_probe(struct platform_device *pdev)
+{
+	const struct acpm_handle *acpm_handle;
+	struct clk_hw_onecell_data *clk_data;
+	struct clk_hw **hws;
+	struct device *dev = &pdev->dev;
+	struct acpm_clk *aclks;
+	unsigned int mbox_chan_id;
+	int i, err, count;
+
+	acpm_handle = devm_acpm_get_by_node(dev, dev->parent->of_node);
+	if (IS_ERR(acpm_handle))
+		return dev_err_probe(dev, PTR_ERR(acpm_handle),
+				     "Failed to get acpm handle\n");
+
+	count = acpm_clk_gs101.nr_clks;
+	mbox_chan_id = acpm_clk_gs101.mbox_chan_id;
+
+	clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, count),
+				GFP_KERNEL);
+	if (!clk_data)
+		return -ENOMEM;
+
+	clk_data->num = count;
+	hws = clk_data->hws;
+
+	aclks = devm_kcalloc(dev, count, sizeof(*aclks), GFP_KERNEL);
+	if (!aclks)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		struct acpm_clk *aclk = &aclks[i];
+
+		/*
+		 * The code assumes the clock IDs start from zero,
+		 * are sequential and do not have gaps.
+		 */
+		aclk->id = i;
+		aclk->handle = acpm_handle;
+		aclk->mbox_chan_id = mbox_chan_id;
+
+		hws[i] = &aclk->hw;
+
+		err = acpm_clk_register(dev, aclk,
+					acpm_clk_gs101.clks[i].name);
+		if (err)
+			return dev_err_probe(dev, err,
+					     "Failed to register clock\n");
+	}
+
+	return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+					   clk_data);
+}
+
+static const struct platform_device_id acpm_clk_id[] = {
+	{ "gs101-acpm-clk" },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, acpm_clk_id);
+
+static struct platform_driver acpm_clk_driver = {
+	.driver	= {
+		.name = "acpm-clocks",
+	},
+	.probe = acpm_clk_probe,
+	.id_table = acpm_clk_id,
+};
+module_platform_driver(acpm_clk_driver);
+
+MODULE_AUTHOR("Tudor Ambarus <[e-mail]>");
+MODULE_DESCRIPTION("Samsung Exynos ACPM clock driver");
+MODULE_LICENSE("GPL");

drivers/firmware/samsung/Makefile

···
 # SPDX-License-Identifier: GPL-2.0-only
 
-acpm-protocol-objs			:= exynos-acpm.o exynos-acpm-pmic.o
+acpm-protocol-objs			:= exynos-acpm.o
+acpm-protocol-objs			+= exynos-acpm-pmic.o
+acpm-protocol-objs			+= exynos-acpm-dvfs.o
 obj-$(CONFIG_EXYNOS_ACPM_PROTOCOL)	+= acpm-protocol.o

drivers/firmware/samsung/exynos-acpm-dvfs.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2025 Linaro Ltd.
+ */
+
+#include <linux/bitfield.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-dvfs.h"
+
+#define ACPM_DVFS_ID			GENMASK(11, 0)
+#define ACPM_DVFS_REQ_TYPE		GENMASK(15, 0)
+
+#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->txd = cmd;
+	xfer->txlen = cmdlen;
+
+	if (response) {
+		xfer->rxd = cmd;
+		xfer->rxlen = cmdlen;
+	}
+}
+
+static void acpm_dvfs_init_set_rate_cmd(u32 cmd[4], unsigned int clk_id,
+					unsigned long rate)
+{
+	cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id);
+	cmd[1] = rate / HZ_PER_KHZ;
+	cmd[2] = FIELD_PREP(ACPM_DVFS_REQ_TYPE, ACPM_DVFS_FREQ_REQ);
+	cmd[3] = ktime_to_ms(ktime_get());
+}
+
+int acpm_dvfs_set_rate(const struct acpm_handle *handle,
+		       unsigned int acpm_chan_id, unsigned int clk_id,
+		       unsigned long rate)
+{
+	struct acpm_xfer xfer = {0};
+	u32 cmd[4];
+
+	acpm_dvfs_init_set_rate_cmd(cmd, clk_id, rate);
+	acpm_dvfs_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id, false);
+
+	return acpm_do_xfer(handle, &xfer);
+}
+
+static void acpm_dvfs_init_get_rate_cmd(u32 cmd[4], unsigned int clk_id)
+{
+	cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id);
+	cmd[2] = FIELD_PREP(ACPM_DVFS_REQ_TYPE, ACPM_DVFS_FREQ_GET);
+	cmd[3] = ktime_to_ms(ktime_get());
+}
+
+unsigned long acpm_dvfs_get_rate(const struct acpm_handle *handle,
+				 unsigned int acpm_chan_id, unsigned int clk_id)
+{
+	struct acpm_xfer xfer;
+	unsigned int cmd[4] = {0};
+	int ret;
+
+	acpm_dvfs_init_get_rate_cmd(cmd, clk_id);
+	acpm_dvfs_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id, true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return 0;
+
+	return xfer.rxd[1] * HZ_PER_KHZ;
+}

drivers/firmware/samsung/exynos-acpm-dvfs.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2025 Linaro Ltd.
+ */
+#ifndef __EXYNOS_ACPM_DVFS_H__
+#define __EXYNOS_ACPM_DVFS_H__
+
+#include <linux/types.h>
+
+struct acpm_handle;
+
+int acpm_dvfs_set_rate(const struct acpm_handle *handle,
+		       unsigned int acpm_chan_id, unsigned int id,
+		       unsigned long rate);
+unsigned long acpm_dvfs_get_rate(const struct acpm_handle *handle,
+				 unsigned int acpm_chan_id,
+				 unsigned int clk_id);
+
+#endif /* __EXYNOS_ACPM_DVFS_H__ */

drivers/firmware/samsung/exynos-acpm.c

···
 #include <linux/types.h>
 
 #include "exynos-acpm.h"
+#include "exynos-acpm-dvfs.h"
 #include "exynos-acpm-pmic.h"
 
 #define ACPM_PROTOCOL_SEQNUM		GENMASK(21, 16)
···
 /**
  * struct acpm_match_data - of_device_id data.
  * @initdata_base:	offset in SRAM where the channels configuration resides.
+ * @acpm_clk_dev_name:	base name for the ACPM clocks device that we're registering.
  */
 struct acpm_match_data {
 	loff_t initdata_base;
+	const char *acpm_clk_dev_name;
 };
 
 #define client_to_acpm_chan(c) container_of(c, struct acpm_chan, cl)
···
  */
 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;
+
+	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->update_reg = acpm_pmic_update_reg;
 }
 
+static void acpm_clk_pdev_unregister(void *data)
+{
+	platform_device_unregister(data);
+}
+
 static int acpm_probe(struct platform_device *pdev)
 {
 	const struct acpm_match_data *match_data;
+	struct platform_device *acpm_clk_pdev;
 	struct device *dev = &pdev->dev;
 	struct device_node *shmem;
 	struct acpm_info *acpm;
···
 	acpm_setup_ops(acpm);
 
 	platform_set_drvdata(pdev, acpm);
+
+	acpm_clk_pdev = platform_device_register_data(dev,
+						match_data->acpm_clk_dev_name,
+						PLATFORM_DEVID_NONE, NULL, 0);
+	if (IS_ERR(acpm_clk_pdev))
+		return dev_err_probe(dev, PTR_ERR(acpm_clk_pdev),
+				     "Failed to register ACPM clocks device.\n");
+
+	ret = devm_add_action_or_reset(dev, acpm_clk_pdev_unregister,
+				       acpm_clk_pdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to add devm action.\n");
 
 	return devm_of_platform_populate(dev);
 }
···
 
 static const struct acpm_match_data acpm_gs101 = {
 	.initdata_base = ACPM_GS101_INITDATA_BASE,
+	.acpm_clk_dev_name = "gs101-acpm-clk",
 };
 
 static const struct of_device_id acpm_match[] = {

include/dt-bindings/clock/google,gs101-acpm.h

···
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/*
+ * Copyright 2025 Linaro Ltd.
+ *
+ * Device Tree binding constants for Google gs101 ACPM clock controller.
+ */
+
+#ifndef _DT_BINDINGS_CLOCK_GOOGLE_GS101_ACPM_H
+#define _DT_BINDINGS_CLOCK_GOOGLE_GS101_ACPM_H
+
+#define GS101_CLK_ACPM_DVFS_MIF				0
+#define GS101_CLK_ACPM_DVFS_INT				1
+#define GS101_CLK_ACPM_DVFS_CPUCL0			2
+#define GS101_CLK_ACPM_DVFS_CPUCL1			3
+#define GS101_CLK_ACPM_DVFS_CPUCL2			4
+#define GS101_CLK_ACPM_DVFS_G3D				5
+#define GS101_CLK_ACPM_DVFS_G3DL2			6
+#define GS101_CLK_ACPM_DVFS_TPU				7
+#define GS101_CLK_ACPM_DVFS_INTCAM			8
+#define GS101_CLK_ACPM_DVFS_TNR				9
+#define GS101_CLK_ACPM_DVFS_CAM				10
+#define GS101_CLK_ACPM_DVFS_MFC				11
+#define GS101_CLK_ACPM_DVFS_DISP			12
+#define GS101_CLK_ACPM_DVFS_BO				13
+
+#endif /* _DT_BINDINGS_CLOCK_GOOGLE_GS101_ACPM_H */

include/linux/firmware/samsung/exynos-acpm-protocol.h

···
 struct acpm_handle;
 struct device_node;
 
+struct acpm_dvfs_ops {
+	int (*set_rate)(const struct acpm_handle *handle,
+			unsigned int acpm_chan_id, unsigned int clk_id,
+			unsigned long rate);
+	unsigned long (*get_rate)(const struct acpm_handle *handle,
+				  unsigned int acpm_chan_id,
+				  unsigned int clk_id);
+};
+
 struct acpm_pmic_ops {
 	int (*read_reg)(const struct acpm_handle *handle,
 			unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
···
 };
 
 struct acpm_ops {
+	struct acpm_dvfs_ops dvfs_ops;
 	struct acpm_pmic_ops pmic_ops;
 };
 
···
 
 struct device;
 
+#if IS_ENABLED(CONFIG_EXYNOS_ACPM_PROTOCOL)
 const struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 						struct device_node *np);
+#else
+
+static inline const struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
+							      struct device_node *np)
+{
+	return NULL;
+}
+#endif
 
 #endif /* __EXYNOS_ACPM_PROTOCOL_H */