Hi,
On 9/26/23 13:24, Shyam Sundar S K wrote:
> Hi Hans,
>
> On 9/26/2023 4:05 PM, Hans de Goede wrote:
>> 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).
>
> PMF is meant for AMD APUs(atleast for now) and the _HID will only be
> made visible if its AMD laptop. So using amdgpu's native BACKLIGHT_RAW
> should be safe, right?
Users can pass say acpi_backlight=video and use the acpi_video
driver for backlight control instead of the native GPU backlight
control.
>
>>
>> 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
>>
>
> I can add this change in the v2, do you insist on this?
Insist is a strong word, but I think that it is a good idea to have
this. Evenutally it looks like this code will need to either integrate with
the drm drivers lot more; or the drm core needs to export some special
hooks for this which the PMF code can then call.
Actually thinking more about this, I think that the right thing to do
here is make some code register brightness control as a cooling device
(which I think is already done in some cases) and then have the PMF
code use the cooling-device APIs for this.
IMHO that would be a much cleaner solution then this hack.
Regards,
Hans
>
> Thanks,
> Shyam
>
>> 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
>>
>
