I think this is a nice generalization on it's own, but it's primarily
prep work for my PPGTT support. Does this bother anyone?
The only down side I can see is we waste 2k of cpu unmappable space
(unless we have something else that is <= 2k and doesn't need to be page
aligned).
v2: Align PDEs to 64b in GTT
Allocate the node dynamically so we can use drm_mm_put_block
Now tested on IGT
Allocate node at the top to avoid fragmentation (Chris)
v3: Use Chris' top down allocator
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/i915_gem_gtt.c | 54 ++++++++++++++++++++++++++-----------
include/drm/drm_mm.h | 3 +++
3 files changed, 42 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 0a9c7cd..9ab6254 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -432,6 +432,7 @@ struct i915_gtt {
#define gtt_total_entries(gtt) ((gtt).total >> PAGE_SHIFT)
struct i915_hw_ppgtt {
+ struct drm_mm_node *node;
struct drm_device *dev;
unsigned num_pd_entries;
struct page **pt_pages;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 975adaa..b825d7b 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -219,6 +219,8 @@ static void gen6_ppgtt_cleanup(struct i915_hw_ppgtt *ppgtt)
{
int i;
+ drm_mm_put_block(ppgtt->node);
+
if (ppgtt->pt_dma_addr) {
for (i = 0; i < ppgtt->num_pd_entries; i++)
pci_unmap_page(ppgtt->dev->pdev,
@@ -235,16 +237,27 @@ static void gen6_ppgtt_cleanup(struct i915_hw_ppgtt *ppgtt)
static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
{
+#define GEN6_PD_ALIGN (PAGE_SIZE * 16)
+#define GEN6_PD_SIZE (512 * PAGE_SIZE)
struct drm_device *dev = ppgtt->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
- unsigned first_pd_entry_in_global_pt;
int i;
int ret = -ENOMEM;
- /* ppgtt PDEs reside in the global gtt pagetable, which has 512*1024
- * entries. For aliasing ppgtt support we just steal them at the end for
- * now. */
- first_pd_entry_in_global_pt = gtt_total_entries(dev_priv->gtt) - 512;
+ /* PPGTT PDEs reside in the GGTT stolen space, and consists of 512
+ * entries. The allocator works in address space sizes, so it's
+ * multiplied by page size. We allocate at the top of the GTT to avoid
+ * fragmentation.
+ */
+ BUG_ON(!drm_mm_initialized(&dev_priv->mm.gtt_space));
+ ret = drm_mm_insert_node_in_range_generic(&dev_priv->mm.gtt_space,
+ ppgtt->node, GEN6_PD_SIZE,
+ GEN6_PD_ALIGN, 0,
+ dev_priv->gtt.mappable_end,
+ dev_priv->gtt.total - PAGE_SIZE,
+ DRM_MM_TOPDOWN);
+ if (ret)
+ return ret;
ppgtt->num_pd_entries = 512;
ppgtt->enable = gen6_ppgtt_enable;
@@ -253,8 +266,10 @@ static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
ppgtt->cleanup = gen6_ppgtt_cleanup;
ppgtt->pt_pages = kzalloc(sizeof(struct page *)*ppgtt->num_pd_entries,
GFP_KERNEL);
- if (!ppgtt->pt_pages)
+ if (!ppgtt->pt_pages) {
+ drm_mm_put_block(ppgtt->node);
return -ENOMEM;
+ }
for (i = 0; i < ppgtt->num_pd_entries; i++) {
ppgtt->pt_pages[i] = alloc_page(GFP_KERNEL);
@@ -284,7 +299,10 @@ static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
ppgtt->clear_range(ppgtt, 0,
ppgtt->num_pd_entries*I915_PPGTT_PT_ENTRIES);
- ppgtt->pd_offset = first_pd_entry_in_global_pt * sizeof(gen6_gtt_pte_t);
+ DRM_DEBUG_DRIVER("Allocated pde space (%ldM) at GTT entry: %lx\n",
+ ppgtt->node->size >> 20,
+ ppgtt->node->start / PAGE_SIZE);
+ ppgtt->pd_offset = ppgtt->node->start / PAGE_SIZE * sizeof(gen6_gtt_pte_t);
return 0;
@@ -315,6 +333,12 @@ static int i915_gem_init_aliasing_ppgtt(struct drm_device *dev)
if (!ppgtt)
return -ENOMEM;
+ ppgtt->node = kzalloc(sizeof(*ppgtt->node), GFP_KERNEL);
+ if (!ppgtt->node) {
+ kfree(ppgtt);
+ return -ENOMEM;
+ }
+
ppgtt->dev = dev;
ppgtt->scratch_page_dma_addr = dev_priv->gtt.scratch_page_dma;
@@ -323,10 +347,12 @@ static int i915_gem_init_aliasing_ppgtt(struct drm_device *dev)
else
BUG();
- if (ret)
+ if (ret) {
+ drm_mm_put_block(ppgtt->node);
kfree(ppgtt);
- else
+ } else {
dev_priv->mm.aliasing_ppgtt = ppgtt;
+ }
return ret;
}
@@ -407,6 +433,9 @@ void i915_gem_restore_gtt_mappings(struct drm_device *dev)
dev_priv->gtt.gtt_clear_range(dev, dev_priv->gtt.start / PAGE_SIZE,
dev_priv->gtt.total / PAGE_SIZE);
+ if (dev_priv->mm.aliasing_ppgtt)
+ gen6_write_pdes(dev_priv->mm.aliasing_ppgtt);
+
list_for_each_entry(obj, &dev_priv->mm.bound_list, gtt_list) {
i915_gem_clflush_object(obj);
i915_gem_gtt_bind_object(obj, obj->cache_level);
@@ -651,12 +680,6 @@ void i915_gem_init_global_gtt(struct drm_device *dev)
if (intel_enable_ppgtt(dev) && HAS_ALIASING_PPGTT(dev)) {
int ret;
- if (INTEL_INFO(dev)->gen <= 7) {
- /* PPGTT pdes are stolen from global gtt ptes, so shrink the
- * aperture accordingly when using aliasing ppgtt. */
- gtt_size -= 512 * PAGE_SIZE;
- }
-
i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
ret = i915_gem_init_aliasing_ppgtt(dev);
@@ -665,7 +688,6 @@ void i915_gem_init_global_gtt(struct drm_device *dev)
DRM_ERROR("Aliased PPGTT setup failed %d\n", ret);
drm_mm_takedown(&dev_priv->mm.gtt_space);
- gtt_size += 512 * PAGE_SIZE;
}
i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
}
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h
index 752e846..ce7b13b 100644
--- a/include/drm/drm_mm.h
+++ b/include/drm/drm_mm.h
@@ -53,6 +53,9 @@ enum drm_mm_search_flags {
DRM_MM_SEARCH_BELOW = 1<<1,
};
+#define DRM_MM_BOTTOMUP DRM_MM_CREATE_DEFAULT, DRM_MM_SEARCH_DEFAULT
+#define DRM_MM_TOPDOWN DRM_MM_CREATE_TOP, DRM_MM_SEARCH_BELOW
+
struct drm_mm_node {
struct list_head node_list;
struct list_head hole_stack;
--
1.8.2.1
