From: Paulo Zanoni Date: Mon, 14 Sep 2015 18:19:57 +0000 (-0300) Subject: drm/i915: avoid the last 8mb of stolen on BDW/SKL X-Git-Tag: firefly_0821_release~176^2~721^2~29^2~31 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a9da512b3ed73045253afd778e40d4298f42905b;p=firefly-linux-kernel-4.4.55.git drm/i915: avoid the last 8mb of stolen on BDW/SKL The FBC hardware for these platforms doesn't have access to the bios_reserved range, so it always assumes the maximum (8mb) is used. So avoid this range while allocating. This solves a bunch of FIFO underruns that happen if you end up putting the CFB in that memory range. On my machine, with 32mb of stolen, I need a 2560x1440 mode for that. Testcase: igt/kms_frontbuffer_tracking/fbc-* (given the right setup) Signed-off-by: Paulo Zanoni Reviewed-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index d4240dba16ff..ffd4ab111957 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3175,6 +3175,10 @@ static inline void i915_gem_chipset_flush(struct drm_device *dev) int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv, struct drm_mm_node *node, u64 size, unsigned alignment); +int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv, + struct drm_mm_node *node, u64 size, + unsigned alignment, u64 start, + u64 end); void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv, struct drm_mm_node *node); int i915_gem_init_stolen(struct drm_device *dev); diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h index 82750073d5b3..96ebb98a476d 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.h +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h @@ -341,6 +341,7 @@ struct i915_gtt { struct i915_address_space base; size_t stolen_size; /* Total size of stolen memory */ + size_t stolen_usable_size; /* Total size minus BIOS reserved */ u64 mappable_end; /* End offset that we can CPU map */ struct io_mapping *mappable; /* Mapping to our CPU mappable region */ phys_addr_t mappable_base; /* PA of our GMADR */ diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index bf26ecc3781b..081ef6d6c94f 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -42,9 +42,9 @@ * for is a boon. */ -int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv, - struct drm_mm_node *node, u64 size, - unsigned alignment) +int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv, + struct drm_mm_node *node, u64 size, + unsigned alignment, u64 start, u64 end) { int ret; @@ -52,13 +52,23 @@ int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv, return -ENODEV; mutex_lock(&dev_priv->mm.stolen_lock); - ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, size, alignment, - DRM_MM_SEARCH_DEFAULT); + ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node, size, + alignment, start, end, + DRM_MM_SEARCH_DEFAULT); mutex_unlock(&dev_priv->mm.stolen_lock); return ret; } +int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv, + struct drm_mm_node *node, u64 size, + unsigned alignment) +{ + return i915_gem_stolen_insert_node_in_range(dev_priv, node, size, + alignment, 0, + dev_priv->gtt.stolen_usable_size); +} + void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv, struct drm_mm_node *node) { @@ -355,9 +365,11 @@ int i915_gem_init_stolen(struct drm_device *dev) dev_priv->gtt.stolen_size >> 10, (dev_priv->gtt.stolen_size - reserved_total) >> 10); + dev_priv->gtt.stolen_usable_size = dev_priv->gtt.stolen_size - + reserved_total; + /* Basic memrange allocator for stolen space */ - drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size - - reserved_total); + drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_usable_size); return 0; } diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index db3809134a29..6f3c2ea75dd8 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -551,6 +551,16 @@ static int find_compression_threshold(struct drm_i915_private *dev_priv, { int compression_threshold = 1; int ret; + u64 end; + + /* The FBC hardware for BDW/SKL doesn't have access to the stolen + * reserved range size, so it always assumes the maximum (8mb) is used. + * If we enable FBC using a CFB on that memory range we'll get FIFO + * underruns, even if that range is not reserved by the BIOS. */ + if (IS_BROADWELL(dev_priv) || IS_SKYLAKE(dev_priv)) + end = dev_priv->gtt.stolen_size - 8 * 1024 * 1024; + else + end = dev_priv->gtt.stolen_usable_size; /* HACK: This code depends on what we will do in *_enable_fbc. If that * code changes, this code needs to change as well. @@ -560,7 +570,8 @@ static int find_compression_threshold(struct drm_i915_private *dev_priv, */ /* Try to over-allocate to reduce reallocations and fragmentation. */ - ret = i915_gem_stolen_insert_node(dev_priv, node, size <<= 1, 4096); + ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1, + 4096, 0, end); if (ret == 0) return compression_threshold; @@ -570,7 +581,8 @@ again: (fb_cpp == 2 && compression_threshold == 2)) return 0; - ret = i915_gem_stolen_insert_node(dev_priv, node, size >>= 1, 4096); + ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1, + 4096, 0, end); if (ret && INTEL_INFO(dev_priv)->gen <= 4) { return 0; } else if (ret) {