On 17.05.2023 16:59, Luca Weiss wrote:
> On Dienstag, 16. Mai 2023 03:27:46 CEST Konrad Dybcio wrote:
>> On 6.05.2023 22:10, Luca Weiss wrote:
>>> On older platforms like msm8226, msm8974 and msm8916 the driver in the
>>> downstream kernel enables scaling first before doing the handover of the
>>> clocks.
>>>
>>> While this normally doesn't seem to cause noticeable problems, on
>>> apq8026-asus-sparrow this causes the device to immediately reboot,
>>> perhaps due to older rpm firmware that becomes unhappy.
>>>
>>> On newer platforms the order has swapped and enabling scaling is done
>>> after the handover, so let's introduce this behavior only conditionally
>>> for msm8226 and msm8974 for now.
>>>
>>> Signed-off-by: Luca Weiss <luca@xxxxxxxxx>
>>> ---
>>
>> Did you give this a spin on some 8974? I think hammerhead had
>> issues around rpmcc in the past..
>
> Yes, appears to be fine on msm8974 also.
>
> I tried to reproduce the hammerhead ocmem hang we had in the past but even
> with v6.3 rpmcc it seems to be fine. But iirc it was happening more or less at
> random in the past so wouldn't be surprised if my tests just didn't show
> anything on accident.
>
> Regards
> Luca
OK sg
Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
Konrad
>
>>
>> Konrad
>>
>>> drivers/clk/qcom/clk-smd-rpm.c | 16 +++++++++++++---
>>> 1 file changed, 13 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/clk/qcom/clk-smd-rpm.c
>>> b/drivers/clk/qcom/clk-smd-rpm.c index 887b945a6fb7..6d5476afc4d1 100644
>>> --- a/drivers/clk/qcom/clk-smd-rpm.c
>>> +++ b/drivers/clk/qcom/clk-smd-rpm.c
>>> @@ -178,6 +178,7 @@ struct clk_smd_rpm_req {
>>>
>>> struct rpm_smd_clk_desc {
>>>
>>> struct clk_smd_rpm **clks;
>>> size_t num_clks;
>>>
>>> + bool scaling_before_handover;
>>>
>>> };
>>>
>>> static DEFINE_MUTEX(rpm_smd_clk_lock);
>>>
>>> @@ -693,6 +694,7 @@ static struct clk_smd_rpm *msm8974_clks[] = {
>>>
>>> static const struct rpm_smd_clk_desc rpm_clk_msm8974 = {
>>>
>>> .clks = msm8974_clks,
>>> .num_clks = ARRAY_SIZE(msm8974_clks),
>>>
>>> + .scaling_before_handover = true,
>>>
>>> };
>>>
>>> static struct clk_smd_rpm *msm8976_clks[] = {
>>>
>>> @@ -1318,6 +1320,12 @@ static int rpm_smd_clk_probe(struct platform_device
>>> *pdev)>
>>> rpm_smd_clks = desc->clks;
>>> num_clks = desc->num_clks;
>>>
>>> + if (desc->scaling_before_handover) {
>>> + ret = clk_smd_rpm_enable_scaling(rpm);
>>> + if (ret)
>>> + goto err;
>>> + }
>>> +
>>>
>>> for (i = 0; i < num_clks; i++) {
>>>
>>> if (!rpm_smd_clks[i])
>>>
>>> continue;
>>>
>>> @@ -1329,9 +1337,11 @@ static int rpm_smd_clk_probe(struct platform_device
>>> *pdev)>
>>> goto err;
>>>
>>> }
>>>
>>> - ret = clk_smd_rpm_enable_scaling(rpm);
>>> - if (ret)
>>> - goto err;
>>> + if (!desc->scaling_before_handover) {
>>> + ret = clk_smd_rpm_enable_scaling(rpm);
>>> + if (ret)
>>> + goto err;
>>> + }
>>>
>>> for (i = 0; i < num_clks; i++) {
>>>
>>> if (!rpm_smd_clks[i])
>>>
>>> ---
>>> base-commit: dd9e11d6477a52ede9ebe575c83285e79e823889
>>> change-id: 20230506-rpmcc-scaling-handover-a63029ed9d13
>>>
>>> Best regards,
>
>
>
>
