1. Patchew
  2. linux
  3. [PATCH 0/3] exynos-acpm: add DVFS protocol and clock driver
  4. View patch

[PATCH 2/3] firmware: exynos-acpm: add DVFS protocol

Tudor Ambarus posted 3 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH 2/3] firmware: exynos-acpm: add DVFS protocol
Posted by Tudor Ambarus 1 month, 2 weeks ago 
Add ACPM DVFS protocol handler. It constructs DVFS messages that
the APM firmware can understand.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/firmware/samsung/Makefile                  |  4 +-
 drivers/firmware/samsung/exynos-acpm-dvfs.c        | 85 ++++++++++++++++++++++
 drivers/firmware/samsung/exynos-acpm-dvfs.h        | 21 ++++++
 drivers/firmware/samsung/exynos-acpm.c             |  5 ++
 .../linux/firmware/samsung/exynos-acpm-protocol.h  | 10 +++
 5 files changed, 124 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/samsung/Makefile b/drivers/firmware/samsung/Makefile
index 7b4c9f6f34f54fd731886d97a615fe1aa97ba9a0..80d4f89b33a9558b68c9083da675c70ec3d05f19 100644
--- a/drivers/firmware/samsung/Makefile
+++ b/drivers/firmware/samsung/Makefile
@@ -1,4 +1,6 @@
 # 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
diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.c b/drivers/firmware/samsung/exynos-acpm-dvfs.c
new file mode 100644
index 0000000000000000000000000000000000000000..ee457c1a3de2ff2e4395d9fc3ff4c13294473b2d
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-dvfs.c
@@ -0,0 +1,85 @@
+// 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)
+
+enum exynos_acpm_dvfs_func {
+	ACPM_DVFS_FREQ_REQ,
+	ACPM_DVFS_FREQ_GET,
+};
+
+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,
+					u32 dbg_val)
+{
+	cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id);
+	cmd[1] = dbg_val;
+	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,
+				 u32 dbg_val)
+{
+	struct acpm_xfer xfer;
+	unsigned int cmd[4];
+	int ret;
+
+	acpm_dvfs_init_get_rate_cmd(cmd, clk_id, dbg_val);
+	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;
+}
diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.h b/drivers/firmware/samsung/exynos-acpm-dvfs.h
new file mode 100644
index 0000000000000000000000000000000000000000..85a10bd535d118f2f36e9888e41b9b705b08ea59
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-dvfs.h
@@ -0,0 +1,21 @@
+/* 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,
+				 u32 dbg_val);
+
+#endif /* __EXYNOS_ACPM_DVFS_H__ */
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index 3a69fe3234c75e0b5a93cbea6bb210dc6f69d2a6..9fa0335ccf5db32892fdf09e8d4b0a885a8f8fb5 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -29,6 +29,7 @@
 #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)
@@ -590,8 +591,12 @@ 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;
 
+	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;
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index f628bf1862c25fa018a2fe5e7e123bf05c5254b9..e41055316bb578bb8250a1b1177f1059eeeb2611 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -13,6 +13,15 @@
 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, u32 dbg_val);
+};
+
 struct acpm_pmic_ops {
 	int (*read_reg)(const struct acpm_handle *handle,
 			unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
@@ -32,6 +41,7 @@ struct acpm_pmic_ops {
 };
 
 struct acpm_ops {
+	struct acpm_dvfs_ops dvfs_ops;
 	struct acpm_pmic_ops pmic_ops;
 };
 

-- 
2.51.0.rc1.167.g924127e9c0-goog
Re: [PATCH 2/3] firmware: exynos-acpm: add DVFS protocol
Posted by Krzysztof Kozlowski 1 month, 1 week ago 
On 19/08/2025 13:45, Tudor Ambarus wrote:
> Add ACPM DVFS protocol handler. It constructs DVFS messages that
> the APM firmware can understand.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> ---
>  drivers/firmware/samsung/Makefile                  |  4 +-
>  drivers/firmware/samsung/exynos-acpm-dvfs.c        | 85 ++++++++++++++++++++++
>  drivers/firmware/samsung/exynos-acpm-dvfs.h        | 21 ++++++
>  drivers/firmware/samsung/exynos-acpm.c             |  5 ++
>  .../linux/firmware/samsung/exynos-acpm-protocol.h  | 10 +++
>  5 files changed, 124 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/samsung/Makefile b/drivers/firmware/samsung/Makefile
> index 7b4c9f6f34f54fd731886d97a615fe1aa97ba9a0..80d4f89b33a9558b68c9083da675c70ec3d05f19 100644
> --- a/drivers/firmware/samsung/Makefile
> +++ b/drivers/firmware/samsung/Makefile
> @@ -1,4 +1,6 @@
>  # 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
> diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.c b/drivers/firmware/samsung/exynos-acpm-dvfs.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..ee457c1a3de2ff2e4395d9fc3ff4c13294473b2d
> --- /dev/null
> +++ b/drivers/firmware/samsung/exynos-acpm-dvfs.c
> @@ -0,0 +1,85 @@
> +// 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)
> +
> +enum exynos_acpm_dvfs_func {
> +	ACPM_DVFS_FREQ_REQ,
> +	ACPM_DVFS_FREQ_GET,
> +};

These are actual values for hardware/firmware? If so, please use rather
defines.

Rest looks good.

Best regards,
Krzysztof
Re: [PATCH 2/3] firmware: exynos-acpm: add DVFS protocol
Posted by Tudor Ambarus 1 month, 1 week ago 

On 8/24/25 6:11 PM, Krzysztof Kozlowski wrote:
> On 19/08/2025 13:45, Tudor Ambarus wrote:
>> Add ACPM DVFS protocol handler. It constructs DVFS messages that
>> the APM firmware can understand.
>>
>> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
>> ---
>>  drivers/firmware/samsung/Makefile                  |  4 +-
>>  drivers/firmware/samsung/exynos-acpm-dvfs.c        | 85 ++++++++++++++++++++++
>>  drivers/firmware/samsung/exynos-acpm-dvfs.h        | 21 ++++++
>>  drivers/firmware/samsung/exynos-acpm.c             |  5 ++
>>  .../linux/firmware/samsung/exynos-acpm-protocol.h  | 10 +++
>>  5 files changed, 124 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/firmware/samsung/Makefile b/drivers/firmware/samsung/Makefile
>> index 7b4c9f6f34f54fd731886d97a615fe1aa97ba9a0..80d4f89b33a9558b68c9083da675c70ec3d05f19 100644
>> --- a/drivers/firmware/samsung/Makefile
>> +++ b/drivers/firmware/samsung/Makefile
>> @@ -1,4 +1,6 @@
>>  # 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
>> diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.c b/drivers/firmware/samsung/exynos-acpm-dvfs.c
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..ee457c1a3de2ff2e4395d9fc3ff4c13294473b2d
>> --- /dev/null
>> +++ b/drivers/firmware/samsung/exynos-acpm-dvfs.c
>> @@ -0,0 +1,85 @@
>> +// 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)
>> +
>> +enum exynos_acpm_dvfs_func {
>> +	ACPM_DVFS_FREQ_REQ,
>> +	ACPM_DVFS_FREQ_GET,
>> +};
> 
> These are actual values for hardware/firmware? If so, please use rather
> defines.

yes, they are. Will do, thanks!

Patchew 2.1-devel-b67e4c2

© 2016 - 2025 Red Hat, Inc.