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@linux.intel.com Cc: Jon Bloomfield jon.bloomfield@intel.com Cc: Daniel Vetter daniel.vetter@intel.com Cc: Sudeep Dutt sudeep.dutt@intel.com Signed-off-by: Niranjana Vishwanathapura niranjana.vishwanathapura@intel.com --- 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