From 8d8d062be6b96b1ba95a3f1a9ecaf218c9458497 Mon Sep 17 00:00:00 2001 From: Daniele Ceraolo Spurio Date: Mon, 27 Mar 2023 18:24:30 -0700 Subject: [PATCH] drm/i915/mtl: Fix MTL stolen memory GGTT mapping The PTEs expect the offset from the base of the fake LMEM region (i.e. the base of stolen) and not from the base of the DSM. Quoting the specs: "Driver will set the Device Memory bit = 1 in the PTE when pointing to a page in DSM and program the PTE with offset from LMEM_BAR. Device Memory Offset from LMEM_BAR is same as offset from BGSM." DSM starts 8MBs from BGSM, so we set dsm_base = 8MB. Signed-off-by: Daniele Ceraolo Spurio Cc: Aravind Iddamsetty Cc: Matt Roper Cc: Lucas De Marchi Cc: Jani Nikula Cc: Nirmoy Das Cc: Fei Yang Cc: Radhakrishna Sripada Reviewed-by: Andi Shyti Reviewed-by: Nirmoy Das Link: https://patchwork.freedesktop.org/patch/msgid/20230328012430.2524330-1-daniele.ceraolospurio@intel.com --- drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c index d8e06e783e30f..8ac376c24aa22 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c @@ -890,8 +890,9 @@ i915_gem_stolen_lmem_setup(struct drm_i915_private *i915, u16 type, if (HAS_LMEMBAR_SMEM_STOLEN(i915)) { /* * MTL dsm size is in GGC register. - * Also MTL uses offset to DSMBASE in ptes, so i915 - * uses dsm_base = 0 to setup stolen region. + * Also MTL uses offset to GSMBASE in ptes, so i915 + * uses dsm_base = 8MBs to setup stolen region, since + * DSMBASE = GSMBASE + 8MB. */ ret = mtl_get_gms_size(uncore); if (ret < 0) { @@ -899,11 +900,11 @@ i915_gem_stolen_lmem_setup(struct drm_i915_private *i915, u16 type, return ERR_PTR(ret); } - dsm_base = 0; + dsm_base = SZ_8M; dsm_size = (resource_size_t)(ret * SZ_1M); GEM_BUG_ON(pci_resource_len(pdev, GEN12_LMEM_BAR) != SZ_256M); - GEM_BUG_ON((dsm_size + SZ_8M) > lmem_size); + GEM_BUG_ON((dsm_base + dsm_size) > lmem_size); } else { /* Use DSM base address instead for stolen memory */ dsm_base = intel_uncore_read64(uncore, GEN12_DSMBASE) & GEN12_BDSM_MASK; @@ -912,14 +913,12 @@ i915_gem_stolen_lmem_setup(struct drm_i915_private *i915, u16 type, dsm_size = ALIGN_DOWN(lmem_size - dsm_base, SZ_1M); } - io_size = dsm_size; - if (HAS_LMEMBAR_SMEM_STOLEN(i915)) { - io_start = pci_resource_start(pdev, GEN12_LMEM_BAR) + SZ_8M; - } else if (pci_resource_len(pdev, GEN12_LMEM_BAR) < lmem_size) { + if (pci_resource_len(pdev, GEN12_LMEM_BAR) < lmem_size) { io_start = 0; io_size = 0; } else { io_start = pci_resource_start(pdev, GEN12_LMEM_BAR) + dsm_base; + io_size = dsm_size; } min_page_size = HAS_64K_PAGES(i915) ? I915_GTT_PAGE_SIZE_64K : -- 2.30.2