Re: [PATCH v2 6/6] venus: pm_helpers: Use dev_pm_genpd_set_hwmode to switch GDSC mode

[Konrad Dybcio]

On 16.08.2023 19:58, Konrad Dybcio wrote:
> On 16.08.2023 16:57, Abel Vesa wrote:
>> From: Jagadeesh Kona <quic_jkona@xxxxxxxxxxx>
>>
>> This change demonstrates the use of dev_pm_genpd_set_hwmode API from
>> video driver to switch the video mvs0 gdsc to SW/HW modes at runtime
>> based on requirement.
>>
>> This change adds a new boolean array member vcodec_pmdomains_hwctrl in
>> venus_resources structure to indicate if GDSC's have HW control support
>> or not. This data is used in vcodec_control_v4() to check if GDSC has
>> support to switch to HW control mode and then call dev_pm_genpd_set_hwmode
>> to switch the GDSC mode.
>>
>> Signed-off-by: Jagadeesh Kona <quic_jkona@xxxxxxxxxxx>
>> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
>> ---
> [...]
> 
>>  static int vcodec_control_v4(struct venus_core *core, u32 coreid, bool enable)
>>  {
>> -	void __iomem *ctrl, *stat;
>> -	u32 val;
>> -	int ret;
>> -
>> -	if (IS_V6(core)) {
>> -		ctrl = core->wrapper_base + WRAPPER_CORE_POWER_CONTROL_V6;
>> -		stat = core->wrapper_base + WRAPPER_CORE_POWER_STATUS_V6;
>> -	} else if (coreid == VIDC_CORE_ID_1) {
>> -		ctrl = core->wrapper_base + WRAPPER_VCODEC0_MMCC_POWER_CONTROL;
>> -		stat = core->wrapper_base + WRAPPER_VCODEC0_MMCC_POWER_STATUS;
>> -	} else {
>> -		ctrl = core->wrapper_base + WRAPPER_VCODEC1_MMCC_POWER_CONTROL;
>> -		stat = core->wrapper_base + WRAPPER_VCODEC1_MMCC_POWER_STATUS;
>> -	}
>> -
>> -	if (enable) {
>> -		writel(0, ctrl);
>> -
>> -		ret = readl_poll_timeout(stat, val, val & BIT(1), 1, 100);
>> -		if (ret)
>> -			return ret;
>> -	} else {
>> -		writel(1, ctrl);
> This removal cries for better explanation.
> 
> Has the venus hw been setting some registers that alter the GDSC's state?
> Or the hardware's expectations of the GDSC state?
Clearly can't read the commit message

Acked-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>

Konrad