[PATCH 12/21] drm/i915/gtt: Introduce kmap|kunmap for dma page

Mika Kuoppala
2015-06-11T17:51:32Z

As there is flushing involved when we have done the cpu
write, make functions for mapping for cpu space. Make macros
to map any type of paging structure.

v2: Make it clear tha flushing kunmap is only for ppgtt (Ville)
v3: Flushing fixed (Ville, Michel). Removed superfluous semicolon

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 77 +++++++++++++++++++------------------
1 file changed, 40 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 60796b7..3ac8671 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -330,15 +330,16 @@ static void cleanup_page_dma(struct drm_device *dev, struct i915_page_dma *p)
memset(p, 0, sizeof(*p));
}

-static void fill_page_dma(struct drm_device *dev, struct i915_page_dma *p,
- const uint64_t val)
+static void *kmap_page_dma(struct i915_page_dma *p)
{
- int i;
- uint64_t * const vaddr = kmap_atomic(p->page);
-
- for (i = 0; i < 512; i++)
- vaddr[i] = val;
+ return kmap_atomic(p->page);
+}

+/* We use the flushing unmap only with ppgtt structures:
+ * page directories, page tables and scratch pages.
+ */
+static void kunmap_page_dma(struct drm_device *dev, void *vaddr)
+{
/* There are only few exceptions for gen >=6. chv and bxt.
* And we are not sure about the latter so play safe for now.
*/
@@ -348,6 +349,21 @@ static void fill_page_dma(struct drm_device *dev, struct i915_page_dma *p,
kunmap_atomic(vaddr);
}

+#define kmap_px(px) kmap_page_dma(&(px)->base)
+#define kunmap_px(ppgtt, vaddr) kunmap_page_dma((ppgtt)->base.dev, (vaddr))
+
+static void fill_page_dma(struct drm_device *dev, struct i915_page_dma *p,
+ const uint64_t val)
+{
+ int i;
+ uint64_t * const vaddr = kmap_page_dma(p);
+
+ for (i = 0; i < 512; i++)
+ vaddr[i] = val;
+
+ kunmap_page_dma(dev, vaddr);
+}
+
static void fill_page_dma_32(struct drm_device *dev, struct i915_page_dma *p,
const uint32_t val32)
{
@@ -503,7 +519,6 @@ static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
while (num_entries) {
struct i915_page_directory *pd;
struct i915_page_table *pt;
- struct page *page_table;

if (WARN_ON(!ppgtt->pdp.page_directory[pdpe]))
continue;
@@ -518,22 +533,18 @@ static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
if (WARN_ON(!pt->base.page))
continue;

- page_table = pt->base.page;
-
last_pte = pte + num_entries;
if (last_pte > GEN8_PTES)
last_pte = GEN8_PTES;

- pt_vaddr = kmap_atomic(page_table);
+ pt_vaddr = kmap_px(pt);

for (i = pte; i < last_pte; i++) {
pt_vaddr[i] = scratch_pte;
num_entries--;
}

- if (!HAS_LLC(ppgtt->base.dev))
- drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt);

pte = 0;
if (++pde == I915_PDES) {
@@ -565,18 +576,14 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
if (pt_vaddr == NULL) {
struct i915_page_directory *pd = ppgtt->pdp.page_directory[pdpe];
struct i915_page_table *pt = pd->page_table[pde];
- struct page *page_table = pt->base.page;
-
- pt_vaddr = kmap_atomic(page_table);
+ pt_vaddr = kmap_px(pt);
}

pt_vaddr[pte] =
gen8_pte_encode(sg_page_iter_dma_address(&sg_iter),
cache_level, true);
if (++pte == GEN8_PTES) {
- if (!HAS_LLC(ppgtt->base.dev))
- drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt_vaddr);
pt_vaddr = NULL;
if (++pde == I915_PDES) {
pdpe++;
@@ -585,11 +592,9 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
pte = 0;
}
}
- if (pt_vaddr) {
- if (!HAS_LLC(ppgtt->base.dev))
- drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
- kunmap_atomic(pt_vaddr);
- }
+
+ if (pt_vaddr)
+ kunmap_px(ppgtt, pt_vaddr);
}

static void __gen8_do_map_pt(gen8_pde_t * const pde,
@@ -869,7 +874,7 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
/* Allocations have completed successfully, so set the bitmaps, and do
* the mappings. */
gen8_for_each_pdpe(pd, &ppgtt->pdp, start, length, temp, pdpe) {
- gen8_pde_t *const page_directory = kmap_atomic(pd->base.page);
+ gen8_pde_t *const page_directory = kmap_px(pd);
struct i915_page_table *pt;
uint64_t pd_len = gen8_clamp_pd(start, length);
uint64_t pd_start = start;
@@ -899,10 +904,7 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
* point we're still relying on insert_entries() */
}

- if (!HAS_LLC(vm->dev))
- drm_clflush_virt_range(page_directory, PAGE_SIZE);
-
- kunmap_atomic(page_directory);
+ kunmap_px(ppgtt, page_directory);

set_bit(pdpe, ppgtt->pdp.used_pdpes);
}
@@ -991,7 +993,8 @@ static void gen6_dump_ppgtt(struct i915_hw_ppgtt *ppgtt, struct seq_file *m)
expected);
seq_printf(m, "\tPDE: %x\n", pd_entry);

- pt_vaddr = kmap_atomic(ppgtt->pd.page_table[pde]->base.page);
+ pt_vaddr = kmap_px(ppgtt->pd.page_table[pde]);
+
for (pte = 0; pte < GEN6_PTES; pte+=4) {
unsigned long va =
(pde * PAGE_SIZE * GEN6_PTES) +
@@ -1013,7 +1016,7 @@ static void gen6_dump_ppgtt(struct i915_hw_ppgtt *ppgtt, struct seq_file *m)
}
seq_puts(m, "\n");
}
- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt_vaddr);
}
}

@@ -1216,12 +1219,12 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
if (last_pte > GEN6_PTES)
last_pte = GEN6_PTES;

- pt_vaddr = kmap_atomic(ppgtt->pd.page_table[act_pt]->base.page);
+ pt_vaddr = kmap_px(ppgtt->pd.page_table[act_pt]);

for (i = first_pte; i < last_pte; i++)
pt_vaddr[i] = scratch_pte;

- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt_vaddr);

num_entries -= last_pte - first_pte;
first_pte = 0;
@@ -1245,21 +1248,21 @@ static void gen6_ppgtt_insert_entries(struct i915_address_space *vm,
pt_vaddr = NULL;
for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
if (pt_vaddr == NULL)
- pt_vaddr = kmap_atomic(ppgtt->pd.page_table[act_pt]->base.page);
+ pt_vaddr = kmap_px(ppgtt->pd.page_table[act_pt]);

pt_vaddr[act_pte] =
vm->pte_encode(sg_page_iter_dma_address(&sg_iter),
cache_level, true, flags);

if (++act_pte == GEN6_PTES) {
- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt_vaddr);
pt_vaddr = NULL;
act_pt++;
act_pte = 0;
}
}
if (pt_vaddr)
- kunmap_atomic(pt_vaddr);
+ kunmap_px(ppgtt, pt_vaddr);
}

static void gen6_initialize_pt(struct i915_address_space *vm,
--
1.9.1