[PATCH v4 5/5] drm/ofdrm: Support big-endian scanout buffers

[Thomas Zimmermann]

Hi

Am 12.10.22 um 09:44 schrieb Arnd Bergmann:
> On Wed, Oct 12, 2022, at 9:40 AM, Thomas Zimmermann wrote:
>> Am 12.10.22 um 09:17 schrieb Arnd Bergmann:
>>> On Wed, Oct 12, 2022, at 8:46 AM, Thomas Zimmermann wrote:
>>
>>> Does qemu mark the device has having a particular endianess then, or
>>> does it switch the layout of the framebuffer to match what the CPU
>>> does?
>>
>> The latter. On neither architecture does qemu expose this flag. The
>> default endianess corresponds to the host.
> 
> "host" as in the machine that qemu runs on, or the machine that is
> being emulated? I suppose it would be broken either way, but in the
> latter case, we could get away with detecting that the machine is
> running under qemu.

Sorry, my mistake. I meant "guest": the endianess of the framebuffer 
corresponds to the endianess of the emulated machine.  Given that many 
graphics cards support LE and BE modes, I assume that this behavior 
mimics real-hardware systems.

Best regards
Thomas

> 
>      Arnd

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
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