[PATCH] cpufreq: mediatek: Raise proc and sram max voltage for MT7622/7623

[Jia-wei Chang (張佳偉)]

Mail loop Sean.Wang for MT7622 cpufreq.


On Fri, 2022-12-02 at 13:37 +0100, Nick wrote:
> It now starts, however, with a lot of those messages (I applied the 
> patch to linux/master and not to linux-next, because next is
> currently 
> not compiling anymore for me):
> 
> > [   10.777041] cpufreq: __target_index: Failed to change cpu 
> > frequency: -22

Hi Nick,

The errno occurs when cpufreq platform driver attempts to do
mtk_cpufreq_voltage_tracking() but it is not able to accomplish voltage
scaling within a certain of times, vtrack_max.

It will needs further debug message to figure it out.

> > [   10.791577] cpu cpu0: cpu0: failed to scale up voltage!
> 
> The complete log:
> 
https://urldefense.com/v3/__https://gist.githubusercontent.com/PolynomialDivision/267c83c7a21a359cbb4e8d99d0303201/raw/28d3568a26634bebef2d91ebe37fc5f76ae58add/mt7622-patch-cpufreq.log__;!!CTRNKA9wMg0ARbw!msWJync96Qc5bvMB-5gCpepj-5zYWizO_98rjuaLWc7fSBNSSpPMPvZqq1mprBgRq11GAqYvf4hUzwZkX_IhM6k0$ 
> 

May I know if this failure log can be 100 % reproduced on your
platform?

Thanks.

>  
> 
> Bests
> Nick
> 
> On 12/2/22 10:52, AngeloGioacchino Del Regno wrote:
> > During the addition of SRAM voltage tracking for CCI scaling, this
> > driver got some voltage limits set for the vtrack algorithm: these
> > were moved to platform data first, then enforced in a later commit
> > 6a17b3876bc8 ("cpufreq: mediatek: Refine
> > mtk_cpufreq_voltage_tracking()")
> > using these as max values for the regulator_set_voltage() calls.
> > 
> > In this case, the vsram/vproc constraints for MT7622 and MT7623
> > were supposed to be the same as MT2701 (and a number of other
> > SoCs),
> > but that turned out to be a mistake because the aforementioned two
> > SoCs' maximum voltage for both VPROC and VPROC_SRAM is 1.36V.
> > 
> > Fix that by adding new platform data for MT7622/7623 declaring the
> > right {proc,sram}_max_volt parameter.
> > 
> > Fixes: ead858bd128d ("cpufreq: mediatek: Move voltage limits to
> > platform data")
> > Fixes: 6a17b3876bc8 ("cpufreq: mediatek: Refine
> > mtk_cpufreq_voltage_tracking()")
> > Signed-off-by: AngeloGioacchino Del Regno <
> > angelogioacchino.delregno at collabora.com>
> > ---
> >   drivers/cpufreq/mediatek-cpufreq.c | 13 +++++++++++--
> >   1 file changed, 11 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/cpufreq/mediatek-cpufreq.c
> > b/drivers/cpufreq/mediatek-cpufreq.c
> > index 7f2680bc9a0f..f9a9f08c75c4 100644
> > --- a/drivers/cpufreq/mediatek-cpufreq.c
> > +++ b/drivers/cpufreq/mediatek-cpufreq.c
> > @@ -695,6 +695,15 @@ static const struct mtk_cpufreq_platform_data
> > mt2701_platform_data = {
> >   	.ccifreq_supported = false,
> >   };
> >   
> > +static const struct mtk_cpufreq_platform_data mt7622_platform_data
> > = {
> > +	.min_volt_shift = 100000,
> > +	.max_volt_shift = 200000,
> > +	.proc_max_volt = 1360000,
> > +	.sram_min_volt = 0,
> > +	.sram_max_volt = 1360000,
> > +	.ccifreq_supported = false,
> > +};
> > +
> >   static const struct mtk_cpufreq_platform_data
> > mt8183_platform_data = {
> >   	.min_volt_shift = 100000,
> >   	.max_volt_shift = 200000,
> > @@ -717,8 +726,8 @@ static const struct mtk_cpufreq_platform_data
> > mt8186_platform_data = {
> >   static const struct of_device_id mtk_cpufreq_machines[]
> > __initconst = {
> >   	{ .compatible = "mediatek,mt2701", .data =
> > &mt2701_platform_data },
> >   	{ .compatible = "mediatek,mt2712", .data =
> > &mt2701_platform_data },
> > -	{ .compatible = "mediatek,mt7622", .data =
> > &mt2701_platform_data },
> > -	{ .compatible = "mediatek,mt7623", .data =
> > &mt2701_platform_data },
> > +	{ .compatible = "mediatek,mt7622", .data =
> > &mt7622_platform_data },
> > +	{ .compatible = "mediatek,mt7623", .data =
> > &mt7622_platform_data },
> >   	{ .compatible = "mediatek,mt8167", .data =
> > &mt2701_platform_data },
> >   	{ .compatible = "mediatek,mt817x", .data =
> > &mt2701_platform_data },
> >   	{ .compatible = "mediatek,mt8173", .data =
> > &mt2701_platform_data },

Hi Angelo,

Thanks for your help.

I also found the similar problem that platforms using incorrect
vsram/vproc constraint platform data.  They are MT8167 and MT8516 which
refer to mt8516.dtsi and the max voltage value of vproc is 1300 mV.

Can you help to fix the correct platform data for MT8167 and MT8516 as
well?

Thanks.