[PATCH 1/5] drm/xe: Fix GT workaround handling

[Lucas De Marchi]

On Wed, Jan 29, 2025 at 03:56:23PM +0000, Tvrtko Ursulin wrote:
>Any rules using engine matching are currently broken due RTP
>processing happening in early init before the list of hardware
>engines has been initialised.

for *gt* workarounds, it only makes sense to have an engine check
if it's something like 

	XE_RTP_ENTRY_FLAG(FOREACH_ENGINE)

... as it doesn't have an engine context. It will loop through all the
engines on that gt and add the entry for that register and it should be
able to do that before the complete engine setup. But indeed, a
quick look on my tgl doesn't show e.g. 14011060649 as being used:

cat /sys/kernel/debug/dri/0/gt0/workarounds

I will have to take another look.

It would be useful to dump gt0/workarounds and gt0/register-save-restore
and check for not having a setting that should be there, adding it to
the commit message.

>
>Fix it my moving the processing to later in the init phase.
>
>Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at igalia.com>
>Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>Cc: Matt Roper <matthew.d.roper at intel.com>
>---
> drivers/gpu/drm/xe/xe_gt.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/xe_gt.c b/drivers/gpu/drm/xe/xe_gt.c
>index 01a4a852b8f4..7feb4b6fb976 100644
>--- a/drivers/gpu/drm/xe/xe_gt.c
>+++ b/drivers/gpu/drm/xe/xe_gt.c
>@@ -380,10 +380,6 @@ int xe_gt_init_early(struct xe_gt *gt)
> 	if (err)
> 		return err;
>
>-	xe_wa_process_gt(gt);
>-	xe_wa_process_oob(gt);
>-	xe_tuning_process_gt(gt);
>-
> 	xe_force_wake_init_gt(gt, gt_to_fw(gt));
> 	spin_lock_init(&gt->global_invl_lock);
>
>@@ -616,6 +612,10 @@ int xe_gt_init(struct xe_gt *gt)
> 	if (err)
> 		return err;
>
>+	xe_wa_process_gt(gt);
>+	xe_wa_process_oob(gt);
>+	xe_tuning_process_gt(gt);

that is too late as we need the gt WAs in place before initializing GuC.

Lucas De Marchi

>+
> 	xe_force_wake_init_engines(gt, gt_to_fw(gt));
>
> 	err = all_fw_domain_init(gt);
>-- 
>2.48.0
>