[PATCH 2/3] drm/exynos: fimd: add HW trigger support

[Marc Zyngier]

On 2016-05-30 23:58, Javier Martinez Canillas wrote:
> Hello Inki,
>
> On 04/05/2016 04:27 AM, Inki Dae wrote:
>> This patch adds HW trigger support on i80 mode.
>>
>> Until now, Exynos DRM only supported SW trigger which was set
>> SWTRGCMD bit of TRIGCON register by CPU to transfer scanout
>> buffer to Display bus device or panel.
>>
>> With this patch, the transmission to Display bus device or
>> panel will be initiated by FIMD controller.
>>
>> Signed-off-by: Inki Dae <inki.dae at samsung.com>
>> ---
>
> There is a regression for the Exynos5800 Peach Pi Chromebook display 
> due
> this patch. The display is blank and I noticed that it only happens 
> when
> HW start trigger is enabled, but works with SW trigger (as it was 
> before).
>
> So for example with the following diff on top of v4.7-rc1, display 
> works
> again. Do you have any hints about what could be the issue?
>
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> index 0444d7fc400d..8c62830e9514 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> @@ -171,7 +171,7 @@ static struct fimd_driver_data
> exynos5420_fimd_driver_data = {
>  	.lcdblk_vt_shift = 24,
>  	.lcdblk_bypass_shift = 15,
>  	.lcdblk_mic_bypass_shift = 11,
> -	.trg_type = I80_HW_TRG,
>  	.has_shadowcon = 1,
>  	.has_vidoutcon = 1,
>  	.has_vtsel = 1,
>
> Best regards,

On a related note, my Exynos5250 Chromebook (snow) has stopped working 
as well since -rc1 has landed. I haven't had time to bisect it yet, but 
the symptoms are vaguely similar (bright white screen).

I'm happy to test patches.

Thanks,

         M.
-- 
Who you jivin' with that Cosmik Debris?