From: Tejas Upadhyay tejas.upadhyay@intel.com
commit ab0d6ef864c5fa820e894ee1a07f861e63851664 upstream.
xe_gt_enable_host_l2_vram() is reading the XE2_GAMREQSTRM_CTRL register that is currently missing the MCR annotation. However, just adding the annotation doesn't work as this function is called before MCR handling is initialized in xe_gt_mcr_init().
xe_gt_enable_host_l2_vram() is used to implement WA 16023588340 that needs to be done as early as possible during initialization in order to be effective since the MMIO writes impact it. In the failure scenario, driver would simply not be able to bind successfully.
Moving xe_gt_enable_host_l2_vram() later, after MCR initialization is done, only incurs a few additional HW accesses, particularly when loading GuC for hwconfig. Binding/unbinding the driver 100 times in BMG still works so it should be ok to start handling the WA a little bit later. This is sufficient to allow adding the MCR annotation to XE2_GAMREQSTRM_CTRL.
Cc: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Tejas Upadhyay tejas.upadhyay@intel.com Reviewed-by: Matt Roper matthew.d.roper@intel.com Reviewed-by: Lucas De Marchi lucas.demarchi@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20240814095614.909774-2-tejas.... Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com --- drivers/gpu/drm/xe/xe_gt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xe/xe_gt.c b/drivers/gpu/drm/xe/xe_gt.c index 0062a5e4d5fac..7737d7266b42a 100644 --- a/drivers/gpu/drm/xe/xe_gt.c +++ b/drivers/gpu/drm/xe/xe_gt.c @@ -555,7 +555,6 @@ int xe_gt_init_hwconfig(struct xe_gt *gt)
xe_gt_mcr_init_early(gt); xe_pat_init(gt); - xe_gt_enable_host_l2_vram(gt);
err = xe_uc_init(>->uc); if (err) @@ -567,6 +566,7 @@ int xe_gt_init_hwconfig(struct xe_gt *gt)
xe_gt_topology_init(gt); xe_gt_mcr_init(gt); + xe_gt_enable_host_l2_vram(gt);
out_fw: xe_force_wake_put(gt_to_fw(gt), XE_FW_GT);