From 9eddd5a9a2aee15d4f0c701388cbdea70e49c6a9 Mon Sep 17 00:00:00 2001 From: Michal Wajdeczko Date: Sun, 26 Sep 2021 22:10:05 +0200 Subject: [PATCH] drm/i915: Use fixed offset for PTEs location We assumed that for all modern GENs the PTEs and register space are split in the GTTMMADR BAR, but while it is true, we should rather use fixed offset as it is defined in the specification. Bspec: 4409, 4457, 4604, 11181, 9027, 13246, 13321, 44980 Signed-off-by: Michal Wajdeczko Cc: CQ Tang Cc: Matt Roper Reviewed-by: Matt Roper Signed-off-by: Matt Roper Link: https://patchwork.freedesktop.org/patch/msgid/20210926201005.1450-1-michal.wajdeczko@intel.com --- drivers/gpu/drm/i915/gt/intel_ggtt.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c index 06576fc1310e9..f09def2b70906 100644 --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c @@ -813,6 +813,21 @@ static unsigned int chv_get_total_gtt_size(u16 gmch_ctrl) return 0; } +static unsigned int gen6_gttmmadr_size(struct drm_i915_private *i915) +{ + /* + * GEN6: GTTMMADR size is 4MB and GTTADR starts at 2MB offset + * GEN8: GTTMMADR size is 16MB and GTTADR starts at 8MB offset + */ + GEM_BUG_ON(GRAPHICS_VER(i915) < 6); + return (GRAPHICS_VER(i915) < 8) ? SZ_4M : SZ_16M; +} + +static unsigned int gen6_gttadr_offset(struct drm_i915_private *i915) +{ + return gen6_gttmmadr_size(i915) / 2; +} + static int ggtt_probe_common(struct i915_ggtt *ggtt, u64 size) { struct drm_i915_private *i915 = ggtt->vm.i915; @@ -821,8 +836,8 @@ static int ggtt_probe_common(struct i915_ggtt *ggtt, u64 size) u32 pte_flags; int ret; - /* For Modern GENs the PTEs and register space are split in the BAR */ - phys_addr = pci_resource_start(pdev, 0) + pci_resource_len(pdev, 0) / 2; + GEM_WARN_ON(pci_resource_len(pdev, 0) != gen6_gttmmadr_size(i915)); + phys_addr = pci_resource_start(pdev, 0) + gen6_gttadr_offset(i915); /* * On BXT+/ICL+ writes larger than 64 bit to the GTT pagetable range -- 2.30.2