Re: [PATCH RESEND v3 5/5] venus: pm_helpers: Use dev_pm_genpd_set_hwmode to switch GDSC mode

[Konrad Dybcio <konrad.dybcio@linaro.org>]

On 11/3/23 11:44, Bryan O'Donoghue wrote:
> On 01/11/2023 09:04, Abel Vesa wrote:
>> From: Jagadeesh Kona <quic_jkona@quicinc.com>
>>
>> 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.
>>
>> Before the GDSC HWCTL was available to the consumer, the venus driver
>> needed to somehow keep the power from collapsing while under the driver
>> control. The only way to do that was to clear the CORE_PWR_DISABLE bit
>> (in wrapper POWER_CONTROL register) and, respectively, set it back after
>> the driver control was completed.
>>
>> Now, that there is a way to switch the GDSC HW/SW control back and
>> forth, the CORE_PWR_DISABLE toggling can be dropped.
>>
>> Signed-off-by: Jagadeesh Kona <quic_jkona@quicinc.com>
>> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
> 
> So I plan to give this a test on rb5 and db410c
> 
> My q here though is - has anybody on the submission list tested this through suspend/resume and vdd min ?
I think that only chromebooks (sc7[12]80) and sc7180-acer-aspire1.dts
are able to hit vddmin upstream as of today

Konrad