Re: [RFC PATCH] Revert "drm/i915: Disable compression tricks on JSL"

[Sebastian Brzezinka <sebastian.brzezinka@intel.com>]

Hi Ville

On Wed Mar 5, 2025 at 3:26 PM UTC, Ville Syrjälä wrote:
> On Wed, Mar 05, 2025 at 02:49:46PM +0000, Sebastian Brzezinka wrote:
>> This reverts commit 0ddae025ab6cefa9aba757da3cd1d27908d70b0e.
>> 
>> According to bspec 14181, CACHE_MODE_0 is a register that's under userspace
>> control, and DISABLE_REPACKING_FOR_COMPRESSION workaround should be already
>> in all recent Mesa releases. So, there is no need to include it in kernel.
>
> igt doesn't have it.
>
>> 
>> Also, this workaround·sporadically fails to load:
>> ```
>> ERROR GT0: engine workaround lost on application! (reg[7000]=0x0,
>> relevant bits were 0x0 vs expected 0x8000)
>> ```
>
> If it somehow fails to load from the kernel why would it
> work from userspace?
>
> Hmm, apparently CACHE_MODE_0 needs the mcr steering stuff.
> Does that fix the verification fail?

Thanks for sugestion. Right now I think that I try to move this wa to
icl_ctx_workarounds_init as both Mat and Chriss notice that register
is a part of the context. 

-- 
Best regards,
Sebastian