Re: [PATCH 5/7] drm/msm/a5xx: Fix VPC protect value in gpu_write()

2020-09-28 Thread AngeloGioacchino Del Regno
Il giorno lun 28 set 2020 alle ore 18:16 Jordan Crouse
 ha scritto:
>
> On Sat, Sep 26, 2020 at 02:51:44PM +0200, khol...@gmail.com wrote:
> > From: Konrad Dybcio 
> >
> > The upstream API for some reason uses logbase2 instead of
> > just passing the argument as-is, whereas downstream CAF
> > kernel does the latter.
> >
> > Hence, a mistake has been made when porting:
> > 4 is the value that's supposed to be passed, but
> > log2(4) = 2. Changing the value to 16 (= 2^4) fixes
> > the issue.
>
> FWIW I think downstream is wrong. Its a lot more intuitive to pass the number 
> of
> registers that should be protected than to force a human to do math.
>
> Jordan
>
Uhm, actually, it's upstream the one forcing to do math... :P
In any case, downstream you have some calls with an explicit log2 and
some others with the "real" number of registers.

Hardware magic register layouts, maybe :)))

-- Angelo

> > Signed-off-by: Konrad Dybcio 
> > Signed-off-by: AngeloGioacchino Del Regno 
> > ---
> >  drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c 
> > b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > index 00df5de3c8e3..b2670af638a3 100644
> > --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > @@ -789,7 +789,7 @@ static int a5xx_hw_init(struct msm_gpu *gpu)
> >
> >   /* VPC */
> >   gpu_write(gpu, REG_A5XX_CP_PROTECT(14), ADRENO_PROTECT_RW(0xE68, 8));
> > - gpu_write(gpu, REG_A5XX_CP_PROTECT(15), ADRENO_PROTECT_RW(0xE70, 4));
> > + gpu_write(gpu, REG_A5XX_CP_PROTECT(15), ADRENO_PROTECT_RW(0xE70, 16));
> >
> >   /* UCHE */
> >   gpu_write(gpu, REG_A5XX_CP_PROTECT(16), ADRENO_PROTECT_RW(0xE80, 16));
> > --
> > 2.28.0
> >
>
> --
> The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
> a Linux Foundation Collaborative Project


Re: [PATCH 5/7] drm/msm/a5xx: Fix VPC protect value in gpu_write()

2020-09-28 Thread Jordan Crouse
On Sat, Sep 26, 2020 at 02:51:44PM +0200, khol...@gmail.com wrote:
> From: Konrad Dybcio 
> 
> The upstream API for some reason uses logbase2 instead of
> just passing the argument as-is, whereas downstream CAF
> kernel does the latter.
> 
> Hence, a mistake has been made when porting:
> 4 is the value that's supposed to be passed, but
> log2(4) = 2. Changing the value to 16 (= 2^4) fixes
> the issue.

FWIW I think downstream is wrong. Its a lot more intuitive to pass the number of
registers that should be protected than to force a human to do math.

Jordan

> Signed-off-by: Konrad Dybcio 
> Signed-off-by: AngeloGioacchino Del Regno 
> ---
>  drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c 
> b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> index 00df5de3c8e3..b2670af638a3 100644
> --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> @@ -789,7 +789,7 @@ static int a5xx_hw_init(struct msm_gpu *gpu)
>  
>   /* VPC */
>   gpu_write(gpu, REG_A5XX_CP_PROTECT(14), ADRENO_PROTECT_RW(0xE68, 8));
> - gpu_write(gpu, REG_A5XX_CP_PROTECT(15), ADRENO_PROTECT_RW(0xE70, 4));
> + gpu_write(gpu, REG_A5XX_CP_PROTECT(15), ADRENO_PROTECT_RW(0xE70, 16));
>  
>   /* UCHE */
>   gpu_write(gpu, REG_A5XX_CP_PROTECT(16), ADRENO_PROTECT_RW(0xE80, 16));
> -- 
> 2.28.0
> 

-- 
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project