[Intel-gfx] [PATCH] drm/i915: Use drm_mm for PPGTT PDEs
Ben Widawsky
ben at bwidawsk.net
Thu Apr 11 04:43:39 CEST 2013
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).
It's RFC because I have only hacked this up and haven't thoroughly
tested a bunch of error and suspend/resume paths.
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
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 | 56 ++++++++++++++++++++++++-------------
2 files changed, 38 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 3877c45..27573d8 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -440,6 +440,7 @@ struct i915_hw_ppgtt {
uint32_t pd_offset;
dma_addr_t *pt_dma_addr;
dma_addr_t scratch_page_dma_addr;
+ struct drm_mm_node node;
/* pte functions, mirroring the interface of the global gtt. */
void (*clear_range)(struct i915_hw_ppgtt *ppgtt,
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 50df194..b474afb 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -75,12 +75,9 @@ static inline gen6_gtt_pte_t gen6_pte_encode(struct drm_device *dev,
return pte;
}
-static int gen6_ppgtt_enable(struct drm_device *dev)
+static void gen6_write_pdes(struct drm_i915_private *dev_priv,
+ struct i915_hw_ppgtt *ppgtt)
{
- drm_i915_private_t *dev_priv = dev->dev_private;
- uint32_t pd_offset;
- struct intel_ring_buffer *ring;
- struct i915_hw_ppgtt *ppgtt = dev_priv->mm.aliasing_ppgtt;
gen6_gtt_pte_t __iomem *pd_addr;
uint32_t pd_entry;
int i;
@@ -97,6 +94,17 @@ static int gen6_ppgtt_enable(struct drm_device *dev)
writel(pd_entry, pd_addr + i);
}
readl(pd_addr);
+}
+
+static int gen6_ppgtt_enable(struct drm_device *dev)
+{
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ uint32_t pd_offset;
+ struct intel_ring_buffer *ring;
+ struct i915_hw_ppgtt *ppgtt = dev_priv->mm.aliasing_ppgtt;
+ int i;
+
+ gen6_write_pdes(dev_priv, ppgtt);
pd_offset = ppgtt->pd_offset;
pd_offset /= 64; /* in cachelines, */
@@ -208,6 +216,8 @@ 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,
@@ -226,15 +236,22 @@ static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
{
struct drm_device *dev = ppgtt->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
- unsigned first_pd_entry_in_global_pt;
+ const u32 pde_size = I915_PPGTT_PD_ENTRIES * sizeof(gen6_gtt_pte_t);
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) - I915_PPGTT_PD_ENTRIES;
+ * entries. Carve out enough space in the cpu unmappable area.
+ */
+ 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, pde_size,
+ PAGE_SIZE, 0,
+ dev_priv->gtt.mappable_end,
+ dev_priv->gtt.total);
+ if (ret)
+ return ret;
+
ppgtt->num_pd_entries = I915_PPGTT_PD_ENTRIES;
ppgtt->enable = gen6_ppgtt_enable;
@@ -243,8 +260,10 @@ 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);
@@ -274,7 +293,9 @@ 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 at GSM offset: %lx\n",
+ ppgtt->node.start / PAGE_SIZE);
+ ppgtt->pd_offset = ppgtt->node.start / PAGE_SIZE;
return 0;
@@ -291,6 +312,7 @@ err_pt_alloc:
__free_page(ppgtt->pt_pages[i]);
}
kfree(ppgtt->pt_pages);
+ drm_mm_put_block(&ppgtt->node);
return ret;
}
@@ -397,6 +419,9 @@ 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, 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);
@@ -641,12 +666,6 @@ 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 -= I915_PPGTT_PD_ENTRIES*PAGE_SIZE;
- }
-
i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
ret = i915_gem_init_aliasing_ppgtt(dev);
@@ -655,7 +674,6 @@ 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 += I915_PPGTT_PD_ENTRIES*PAGE_SIZE;
}
i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
}
--
1.8.2.1
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