drm/i915: Not all mappable regions require GTT fence regions

Combining map_and_fenceable revealed a bug in
i915_gem_object_gtt_size() in that it always computed the appropriate
fence size for the object regardless of tiling state which caused us to
over-allocate linear buffers when binding to the GTT.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This commit is contained in:
Chris Wilson 2010-11-09 11:47:32 +00:00
parent 05394f3975
commit 92b88aeb1a

View file

@ -41,9 +41,6 @@ struct change_domains {
uint32_t flush_rings;
};
static uint32_t i915_gem_get_gtt_alignment(struct drm_i915_gem_object *obj);
static uint32_t i915_gem_get_gtt_size(struct drm_i915_gem_object *obj);
static int i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj,
bool pipelined);
static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
@ -1443,6 +1440,28 @@ i915_gem_free_mmap_offset(struct drm_i915_gem_object *obj)
list->map = NULL;
}
static uint32_t
i915_gem_get_gtt_size(struct drm_i915_gem_object *obj)
{
struct drm_device *dev = obj->base.dev;
uint32_t size;
if (INTEL_INFO(dev)->gen >= 4 ||
obj->tiling_mode == I915_TILING_NONE)
return obj->base.size;
/* Previous chips need a power-of-two fence region when tiling */
if (INTEL_INFO(dev)->gen == 3)
size = 1024*1024;
else
size = 512*1024;
while (size < obj->base.size)
size <<= 1;
return size;
}
/**
* i915_gem_get_gtt_alignment - return required GTT alignment for an object
* @obj: object to check
@ -1505,34 +1524,6 @@ i915_gem_get_unfenced_gtt_alignment(struct drm_i915_gem_object *obj)
return tile_height * obj->stride * 2;
}
static uint32_t
i915_gem_get_gtt_size(struct drm_i915_gem_object *obj)
{
struct drm_device *dev = obj->base.dev;
uint32_t size;
/*
* Minimum alignment is 4k (GTT page size), but might be greater
* if a fence register is needed for the object.
*/
if (INTEL_INFO(dev)->gen >= 4)
return obj->base.size;
/*
* Previous chips need to be aligned to the size of the smallest
* fence register that can contain the object.
*/
if (INTEL_INFO(dev)->gen == 3)
size = 1024*1024;
else
size = 512*1024;
while (size < obj->base.size)
size <<= 1;
return size;
}
/**
* i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
* @dev: DRM device