[PATCH v2 0/2] Fixes for omapdrm console

[Thomas Zimmermann]

Hi

Am 26.02.24 um 10:01 schrieb Tomi Valkeinen:
> On 26/02/2024 10:26, Tomi Valkeinen wrote:
>> Hi Tony,
>>
>> On 25/02/2024 08:46, Tony Lindgren wrote:
>>> Here are two fixes for omapdrm console.
>>
>> How is it broken? I don't usually use the console (or fbdev) but 
>> enabling it now, it seems to work fine for me, on DRA76 EVM with HDMI 
>> output.

Omapdrm implements drm_framebuffer_funcs.dirty 
withomap_framebuffer_dirty(). AFAIK DRM semantics requires to run the 
dirty helper after writing to the framebuffer's memory. Userspace does 
this via the DIRTYFB ioctl. [1] But (at least) for correctness the 
console needs to do the same.

[1] 
https://elixir.bootlin.com/linux/v6.7.6/source/drivers/gpu/drm/drm_ioctl.c#L679

>
> After applying your patches, I see a lot of cache-related artifacts on 
> the screen when updating the fb.

I guess we might need a dma-specific mmap helper to make this work 
correctly.

Best regards
Thomas

>
>  Tomi
>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
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