The firmware exposes clocks that can be controlled via the ACPM
interface. Describe the clocks exposed by the APM firmware.
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
.../bindings/firmware/google,gs101-acpm-ipc.yaml | 28 ++++++++++++++++++++++
include/dt-bindings/clock/google,gs101.h | 15 ++++++++++++
2 files changed, 43 insertions(+)
diff --git a/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml b/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
index 9785aac3b5f34955bbfe2718eec48581d050954f..27cdf9c881ca680e78e77a0e14ffcffeba970871 100644
--- a/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
+++ b/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
@@ -27,6 +27,29 @@ properties:
mboxes:
maxItems: 1
+ clocks:
+ 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.
+ type: object
+ additionalProperties: false
+
+ properties:
+ compatible:
+ const: google,gs101-acpm-dvfs-clocks
+
+ "#clock-cells":
+ const: 1
+ description:
+ The argument is the ID of the clock contained by the firmware
+ messages.
+
+ required:
+ - compatible
+ - "#clock-cells"
+
pmic:
description: Child node describing the main PMIC.
type: object
@@ -59,6 +82,11 @@ examples:
mboxes = <&ap2apm_mailbox>;
shmem = <&apm_sram>;
+ clocks {
+ compatible = "google,gs101-acpm-dvfs-clocks";
+ #clock-cells = <1>;
+ };
+
pmic {
compatible = "samsung,s2mpg10-pmic";
interrupts-extended = <&gpa0 6 IRQ_TYPE_LEVEL_LOW>;
diff --git a/include/dt-bindings/clock/google,gs101.h b/include/dt-bindings/clock/google,gs101.h
index 442f9e9037dc33198a1cee20af62fc70bbd96605..f1d0df412fdd49b300db4ba88bc0b1674cf0cdf8 100644
--- a/include/dt-bindings/clock/google,gs101.h
+++ b/include/dt-bindings/clock/google,gs101.h
@@ -634,4 +634,19 @@
#define CLK_GOUT_PERIC1_CLK_PERIC1_USI9_USI_CLK 45
#define CLK_GOUT_PERIC1_SYSREG_PERIC1_PCLK 46
+#define CLK_ACPM_DVFS_MIF 0
+#define CLK_ACPM_DVFS_INT 1
+#define CLK_ACPM_DVFS_CPUCL0 2
+#define CLK_ACPM_DVFS_CPUCL1 3
+#define CLK_ACPM_DVFS_CPUCL2 4
+#define CLK_ACPM_DVFS_G3D 5
+#define CLK_ACPM_DVFS_G3DL2 6
+#define CLK_ACPM_DVFS_TPU 7
+#define CLK_ACPM_DVFS_INTCAM 8
+#define CLK_ACPM_DVFS_TNR 9
+#define CLK_ACPM_DVFS_CAM 10
+#define CLK_ACPM_DVFS_MFC 11
+#define CLK_ACPM_DVFS_DISP 12
+#define CLK_ACPM_DVFS_BO 13
+
#endif /* _DT_BINDINGS_CLOCK_GOOGLE_GS101_H */
--
2.51.0.rc1.167.g924127e9c0-googOn Tue, Aug 19, 2025 at 11:45:36AM +0000, Tudor Ambarus wrote:
> The firmware exposes clocks that can be controlled via the ACPM
> interface. Describe the clocks exposed by the APM firmware.
ACPM? APM is Advanced Power Management aka the predecessor to ACPI?
>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> ---
> .../bindings/firmware/google,gs101-acpm-ipc.yaml | 28 ++++++++++++++++++++++
> include/dt-bindings/clock/google,gs101.h | 15 ++++++++++++
> 2 files changed, 43 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml b/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
> index 9785aac3b5f34955bbfe2718eec48581d050954f..27cdf9c881ca680e78e77a0e14ffcffeba970871 100644
> --- a/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
> +++ b/Documentation/devicetree/bindings/firmware/google,gs101-acpm-ipc.yaml
> @@ -27,6 +27,29 @@ properties:
> mboxes:
> maxItems: 1
>
> + clocks:
> + 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.
> + type: object
> + additionalProperties: false
You don't need a child node. Just add #clock-cells to the parent.
> +
> + properties:
> + compatible:
> + const: google,gs101-acpm-dvfs-clocks
> +
> + "#clock-cells":
> + const: 1
> + description:
> + The argument is the ID of the clock contained by the firmware
> + messages.
> +
> + required:
> + - compatible
> + - "#clock-cells"
> +
> pmic:
> description: Child node describing the main PMIC.
> type: object
> @@ -59,6 +82,11 @@ examples:
> mboxes = <&ap2apm_mailbox>;
> shmem = <&apm_sram>;
>
> + clocks {
> + compatible = "google,gs101-acpm-dvfs-clocks";
> + #clock-cells = <1>;
> + };
> +
> pmic {
> compatible = "samsung,s2mpg10-pmic";
> interrupts-extended = <&gpa0 6 IRQ_TYPE_LEVEL_LOW>;
> diff --git a/include/dt-bindings/clock/google,gs101.h b/include/dt-bindings/clock/google,gs101.h
> index 442f9e9037dc33198a1cee20af62fc70bbd96605..f1d0df412fdd49b300db4ba88bc0b1674cf0cdf8 100644
> --- a/include/dt-bindings/clock/google,gs101.h
> +++ b/include/dt-bindings/clock/google,gs101.h
> @@ -634,4 +634,19 @@
> #define CLK_GOUT_PERIC1_CLK_PERIC1_USI9_USI_CLK 45
> #define CLK_GOUT_PERIC1_SYSREG_PERIC1_PCLK 46
>
> +#define CLK_ACPM_DVFS_MIF 0
> +#define CLK_ACPM_DVFS_INT 1
> +#define CLK_ACPM_DVFS_CPUCL0 2
> +#define CLK_ACPM_DVFS_CPUCL1 3
> +#define CLK_ACPM_DVFS_CPUCL2 4
> +#define CLK_ACPM_DVFS_G3D 5
> +#define CLK_ACPM_DVFS_G3DL2 6
> +#define CLK_ACPM_DVFS_TPU 7
> +#define CLK_ACPM_DVFS_INTCAM 8
> +#define CLK_ACPM_DVFS_TNR 9
> +#define CLK_ACPM_DVFS_CAM 10
> +#define CLK_ACPM_DVFS_MFC 11
> +#define CLK_ACPM_DVFS_DISP 12
> +#define CLK_ACPM_DVFS_BO 13
> +
> #endif /* _DT_BINDINGS_CLOCK_GOOGLE_GS101_H */
>
> --
> 2.51.0.rc1.167.g924127e9c0-goog
>
Hi, Rob, On 8/22/25 2:55 PM, Rob Herring wrote: > On Tue, Aug 19, 2025 at 11:45:36AM +0000, Tudor Ambarus wrote: >> The firmware exposes clocks that can be controlled via the ACPM >> interface. Describe the clocks exposed by the APM firmware. > > ACPM? APM is Advanced Power Management aka the predecessor to ACPI? ACPM (Alive Clock and Power Manager) is a firmware that operates on the APM (Active Power Management) module that handles overall power management activities. APM is built around a GREBE processor. In linux we have an ACPM protocol driver that communicates with the firmware via mailbox channels. It's similar to arm,scmi if you want. Cheers, ta
On 22/08/2025 17:03, Tudor Ambarus wrote: > Hi, Rob, > > On 8/22/25 2:55 PM, Rob Herring wrote: >> On Tue, Aug 19, 2025 at 11:45:36AM +0000, Tudor Ambarus wrote: >>> The firmware exposes clocks that can be controlled via the ACPM >>> interface. Describe the clocks exposed by the APM firmware. >> >> ACPM? APM is Advanced Power Management aka the predecessor to ACPI? > > ACPM (Alive Clock and Power Manager) is a firmware that operates on the Please unwrap the acronym in one place of bindings commit msgs. > APM (Active Power Management) module that handles overall power management > activities. APM is built around a GREBE processor. > > In linux we have an ACPM protocol driver that communicates with the firmware > via mailbox channels. It's similar to arm,scmi if you want. Rest of Rob's comment seems valid, so this also invalidates the DTS. Best regards, Krzysztof
On 8/24/25 6:00 PM, Krzysztof Kozlowski wrote: > On 22/08/2025 17:03, Tudor Ambarus wrote: >> Hi, Rob, >> >> On 8/22/25 2:55 PM, Rob Herring wrote: >>> On Tue, Aug 19, 2025 at 11:45:36AM +0000, Tudor Ambarus wrote: >>>> The firmware exposes clocks that can be controlled via the ACPM >>>> interface. Describe the clocks exposed by the APM firmware. >>> >>> ACPM? APM is Advanced Power Management aka the predecessor to ACPI? >> >> ACPM (Alive Clock and Power Manager) is a firmware that operates on the > > Please unwrap the acronym in one place of bindings commit msgs. Okay. > >> APM (Active Power Management) module that handles overall power management >> activities. APM is built around a GREBE processor. >> >> In linux we have an ACPM protocol driver that communicates with the firmware >> via mailbox channels. It's similar to arm,scmi if you want. > > Rest of Rob's comment seems valid, so this also invalidates the DTS. > I assume Rob and you are suggesting to drop the child node and add #clock-cells to the parent. Then define the specific clock data in the parent and create a platform device by hand for the clocks with platform_device_register_data(). I think this works well as what's used in the kernel is just the clock mailbox channel id, clock IDs and clock names. And these can be defined with parent's compatible data. Please correct me if I understood it wrong. Cheers, ta
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