From d9a1ae0d17bdc444eefee6bc5f0dd11e875bd735 Mon Sep 17 00:00:00 2001 From: Daniele Ceraolo Spurio Date: Fri, 13 Dec 2024 10:10:12 -0800 Subject: [PATCH] drm/xe/guc: Enable WA_DUAL_QUEUE for newer platforms The DUAL_QUEUE_WA tells the GuC to not allow concurrent submissions on RCS and CCSes with different address spaces, which on DG2 is required as a WA for an HW bug. On newer platforms, this block has been moved in HW at the CS level, by stalling the RCS/CCS context switch when one of the other RCS/CCSes is busy with a different address space. While functionally correct, having a submission stalled on the HW limits the GuC ability to shuffle things around and can cause complications if the non-stalled submission runs for a long time, because the GuC doesn't know that the stalled submission isn't actually running and might declare it as hung. Therefore, we enable the DUAL_QUEUE_WA on all newer platforms to move management back to the GuC. Note that the GuC specs also recommend enabling this for all platforms starting from MTL that have a CCS. v2: only apply the WA on GTs that have CCS engines v3: split comment (Jonathan) Signed-off-by: Daniele Ceraolo Spurio Cc: John Harrison Cc: Jesus Narvaez Cc: Jonathan Cavitt Reviewed-by: Jonathan Cavitt Link: https://patchwork.freedesktop.org/patch/msgid/20241213181012.2178794-1-daniele.ceraolospurio@intel.com --- drivers/gpu/drm/xe/xe_guc.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c index 4e2868efb6206..408365dfe4eed 100644 --- a/drivers/gpu/drm/xe/xe_guc.c +++ b/drivers/gpu/drm/xe/xe_guc.c @@ -147,6 +147,34 @@ static u32 guc_ctl_ads_flags(struct xe_guc *guc) return flags; } +static bool needs_wa_dual_queue(struct xe_gt *gt) +{ + /* + * The DUAL_QUEUE_WA tells the GuC to not allow concurrent submissions + * on RCS and CCSes with different address spaces, which on DG2 is + * required as a WA for an HW bug. + */ + if (XE_WA(gt, 22011391025)) + return true; + + /* + * On newer platforms, the HW has been updated to not allow parallel + * execution of different address spaces, so the RCS/CCS will stall the + * context switch if one of the other RCS/CCSes is busy with a different + * address space. While functionally correct, having a submission + * stalled on the HW limits the GuC ability to shuffle things around and + * can cause complications if the non-stalled submission runs for a long + * time, because the GuC doesn't know that the stalled submission isn't + * actually running and might declare it as hung. Therefore, we enable + * the DUAL_QUEUE_WA on all newer platforms on GTs that have CCS engines + * to move management back to the GuC. + */ + if (CCS_MASK(gt) && GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) + return true; + + return false; +} + static u32 guc_ctl_wa_flags(struct xe_guc *guc) { struct xe_device *xe = guc_to_xe(guc); @@ -159,7 +187,7 @@ static u32 guc_ctl_wa_flags(struct xe_guc *guc) if (XE_WA(gt, 14014475959)) flags |= GUC_WA_HOLD_CCS_SWITCHOUT; - if (XE_WA(gt, 22011391025)) + if (needs_wa_dual_queue(gt)) flags |= GUC_WA_DUAL_QUEUE; /* -- 2.39.5