Hi,
On 9/22/23 19:50, Shyam Sundar S K wrote:
> For the Smart PC Solution to fully work, it has to enact to the actions
> coming from TA. Add the initial code path for set interface to AMDGPU.
>
> Co-developed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_pmf.c | 21 +++++++++++++++++++++
> drivers/platform/x86/amd/pmf/pmf.h | 2 ++
> drivers/platform/x86/amd/pmf/tee-if.c | 19 +++++++++++++++++--
> include/linux/amd-pmf-io.h | 1 +
> 4 files changed, 41 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pmf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pmf.c
> index 232d11833ddc..5c567bff0548 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pmf.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pmf.c
> @@ -68,3 +68,24 @@ int amd_pmf_get_gfx_data(struct amd_gpu_pmf_data *pmf)
> return 0;
> }
> EXPORT_SYMBOL_GPL(amd_pmf_get_gfx_data);
> +
> +int amd_pmf_set_gfx_data(struct amd_gpu_pmf_data *pmf)
> +{
> + struct drm_device *drm_dev = pci_get_drvdata(pmf->gpu_dev);
> + struct amdgpu_device *adev = drm_to_adev(drm_dev);
> + struct backlight_device *bd;
> +
> + if (!(adev->flags & AMD_IS_APU)) {
> + DRM_ERROR("PMF-AMDGPU interface not supported\n");
> + return -ENODEV;
> + }
> +
> + bd = backlight_device_get_by_type(BACKLIGHT_RAW);
> + if (!bd)
> + return -ENODEV;
This assumes that the backlight is always controller by the amdgpu's
native backlight driver, but it might e.g. also be handled by
eacpi-video or by nvidia_wmi_ec_backlight (when using an AMD APU +
nvidia dgpu).
For now what should be done here is to call acpi_video_get_backlight_type()
and then translate the return value from this into a backlight-type:
acpi_backlight_video -> BACKLIGHT_FIRMWARE
acpi_backlight_vendor, -> BACKLIGHT_PLATFORM
acpi_backlight_native, -> BACKLIGHT_RAW
acpi_backlight_nvidia_wmi_ec, -> BACKLIGHT_FIRMWARE
acpi_backlight_apple_gmux, -> BACKLIGHT_PLATFORM
Also I'm worried about probe order here, this code currently assumes
that the GPU or other backlight driver has loaded before this runs,
which is not necessarily the case.
I think that if the backlight_device_get_by_type() fails this
should be retried say every 10 seconds from some delayed workqueue
for at least a couple of minutes after boot.
Regards,
Hans
> +
> + backlight_device_set_brightness(bd, pmf->brightness);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(amd_pmf_set_gfx_data);
> diff --git a/drivers/platform/x86/amd/pmf/pmf.h b/drivers/platform/x86/amd/pmf/pmf.h
> index 9032df4ba48a..ce89cc0daa5a 100644
> --- a/drivers/platform/x86/amd/pmf/pmf.h
> +++ b/drivers/platform/x86/amd/pmf/pmf.h
> @@ -73,6 +73,7 @@
> #define PMF_POLICY_STT_SKINTEMP_APU 7
> #define PMF_POLICY_STT_SKINTEMP_HS2 8
> #define PMF_POLICY_SYSTEM_STATE 9
> +#define PMF_POLICY_DISPLAY_BRIGHTNESS 12
> #define PMF_POLICY_P3T 38
>
> /* TA macros */
> @@ -480,6 +481,7 @@ enum ta_pmf_error_type {
> };
>
> struct pmf_action_table {
> + unsigned long display_brightness;
> enum system_state system_state;
> unsigned long spl; /* in mW */
> unsigned long sppt; /* in mW */
> diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c
> index 1608996654e8..eefffff83a4c 100644
> --- a/drivers/platform/x86/amd/pmf/tee-if.c
> +++ b/drivers/platform/x86/amd/pmf/tee-if.c
> @@ -79,10 +79,10 @@ static int amd_pmf_update_uevents(struct amd_pmf_dev *dev, u16 event)
> return 0;
> }
>
> -static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_result *out)
> +static int amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_result *out)
> {
> u32 val, event = 0;
> - int idx;
> + int idx, ret;
>
> for (idx = 0; idx < out->actions_count; idx++) {
> val = out->actions_list[idx].value;
> @@ -160,8 +160,23 @@ static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_
> dev->prev_data->system_state = 0;
> }
> break;
> +
> + case PMF_POLICY_DISPLAY_BRIGHTNESS:
> + ret = amd_pmf_get_gfx_data(&dev->gfx_data);
> + if (ret)
> + return ret;
> +
> + dev->prev_data->display_brightness = dev->gfx_data.brightness;
> + if (dev->prev_data->display_brightness != val) {
> + dev->gfx_data.brightness = val;
> + amd_pmf_set_gfx_data(&dev->gfx_data);
> + dev_dbg(dev->dev, "update DISPLAY_BRIGHTNESS : %d\n", val);
> + }
> + break;
> }
> }
> +
> + return 0;
> }
>
> static int amd_pmf_invoke_cmd_enact(struct amd_pmf_dev *dev)
> diff --git a/include/linux/amd-pmf-io.h b/include/linux/amd-pmf-io.h
> index a2d4af231362..ecae387ddaa6 100644
> --- a/include/linux/amd-pmf-io.h
> +++ b/include/linux/amd-pmf-io.h
> @@ -25,4 +25,5 @@ struct amd_gpu_pmf_data {
> };
>
> int amd_pmf_get_gfx_data(struct amd_gpu_pmf_data *pmf);
> +int amd_pmf_set_gfx_data(struct amd_gpu_pmf_data *pmf);
> #endif
