For Shared Virtual Memory (SVM) system (SYS) allocator, there is no
backing buffer object (BO). Add support to bind a VA to PA mapping
in the device page table.
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Jon Bloomfield <jon.bloomfield@xxxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Cc: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 60 ++++++++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_gem_gtt.h | 10 +++++
2 files changed, 68 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 44ff4074db12..d9e95229ba1d 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -183,6 +183,50 @@ static void ppgtt_unbind_vma(struct i915_vma *vma)
vma->vm->clear_range(vma->vm, vma->node.start, vma->size);
}
+int svm_bind_addr_prepare(struct i915_address_space *vm, u64 start, u64 size)
+{
+ return vm->allocate_va_range(vm, start, size);
+}
+
+int svm_bind_addr_commit(struct i915_address_space *vm, u64 start, u64 size,
+ u64 flags, struct sg_table *st, u32 sg_page_sizes)
+{
+ struct i915_vma vma = {0};
+ u32 pte_flags = 0;
+
+ /* use a vma wrapper */
+ vma.page_sizes.sg = sg_page_sizes;
+ vma.node.start = start;
+ vma.node.size = size;
+ vma.pages = st;
+ vma.vm = vm;
+
+ /* Applicable to VLV, and gen8+ */
+ if (flags & I915_GTT_SVM_READONLY)
+ pte_flags |= PTE_READ_ONLY;
+
+ vm->insert_entries(vm, &vma, 0, pte_flags);
+ return 0;
+}
+
+int svm_bind_addr(struct i915_address_space *vm, u64 start, u64 size,
+ u64 flags, struct sg_table *st, u32 sg_page_sizes)
+{
+ int ret;
+
+ ret = svm_bind_addr_prepare(vm, start, size);
+ if (ret)
+ return ret;
+
+ return svm_bind_addr_commit(vm, start, size, flags, st, sg_page_sizes);
+}
+
+void svm_unbind_addr(struct i915_address_space *vm,
+ u64 start, u64 size)
+{
+ vm->clear_range(vm, start, size);
+}
+
static int ppgtt_set_pages(struct i915_vma *vma)
{
GEM_BUG_ON(vma->pages);
@@ -973,11 +1017,21 @@ static u64 __gen8_ppgtt_clear(struct i915_address_space * const vm,
DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n",
__func__, vm, lvl + 1, start, end,
idx, len, atomic_read(px_used(pd)));
- GEM_BUG_ON(!len || len >= atomic_read(px_used(pd)));
+ /*
+ * FIXME: In SVM case, during mmu invalidation, we need to clear ppgtt,
+ * but we don't know if the entry exist or not. So, we can't assume
+ * that it is called only when the entry exist. revisit.
+ * Also need to add the ebility to properly handle partial invalidations
+ * by downgrading the large mappings.
+ */
+ GEM_BUG_ON(!len);
do {
struct i915_page_table *pt = pd->entry[idx];
+ if (!pt)
+ continue;
+
if (atomic_fetch_inc(&pt->used) >> gen8_pd_shift(1) &&
gen8_pd_contains(start, end, lvl)) {
DBG("%s(%p):{ lvl:%d, idx:%d, start:%llx, end:%llx } removing pd\n",
@@ -1000,7 +1054,9 @@ static u64 __gen8_ppgtt_clear(struct i915_address_space * const vm,
__func__, vm, lvl, start, end,
gen8_pd_index(start, 0), count,
atomic_read(&pt->used));
- GEM_BUG_ON(!count || count >= atomic_read(&pt->used));
+ GEM_BUG_ON(!count);
+ if (count > atomic_read(&pt->used))
+ count = atomic_read(&pt->used);
vaddr = kmap_atomic_px(pt);
memset64(vaddr + gen8_pd_index(start, 0),
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index d618a5787c61..6a8d55490e39 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -39,6 +39,7 @@
#include <linux/mm.h>
#include <linux/pagevec.h>
#include <linux/workqueue.h>
+#include <linux/scatterlist.h>
#include <drm/drm_mm.h>
@@ -678,4 +679,13 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
#define PIN_OFFSET_MASK (-I915_GTT_PAGE_SIZE)
+/* SVM API */
+#define I915_GTT_SVM_READONLY BIT(0)
+
+int svm_bind_addr_prepare(struct i915_address_space *vm, u64 start, u64 size);
+int svm_bind_addr_commit(struct i915_address_space *vm, u64 start, u64 size,
+ u64 flags, struct sg_table *st, u32 sg_page_sizes);
+int svm_bind_addr(struct i915_address_space *vm, u64 start, u64 size,
+ u64 flags, struct sg_table *st, u32 sg_page_sizes);
+void svm_unbind_addr(struct i915_address_space *vm, u64 start, u64 size);
#endif
--
2.21.0.rc0.32.g243a4c7e27
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