diff options
| -rw-r--r-- | src/intel/vulkan/anv_allocator.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/intel/vulkan/anv_allocator.c b/src/intel/vulkan/anv_allocator.c index 784191ed97a..5f5577f2781 100644 --- a/src/intel/vulkan/anv_allocator.c +++ b/src/intel/vulkan/anv_allocator.c @@ -993,6 +993,25 @@ anv_scratch_pool_alloc(struct anv_device *device, struct anv_scratch_pool *pool, anv_bo_init_new(&bo->bo, device, size); + /* Even though the Scratch base pointers in 3DSTATE_*S are 64 bits, they + * are still relative to the general state base address. When we emit + * STATE_BASE_ADDRESS, we set general state base address to 0 and the size + * to the maximum (1 page under 4GB). This allows us to just place the + * scratch buffers anywhere we wish in the bottom 32 bits of address space + * and just set the scratch base pointer in 3DSTATE_*S using a relocation. + * However, in order to do so, we need to ensure that the kernel does not + * place the scratch BO above the 32-bit boundary. + * + * NOTE: Technically, it can't go "anywhere" because the top page is off + * limits. However, when EXEC_OBJECT_SUPPORTS_48B_ADDRESS is set, the + * kernel allocates space using + * + * end = min_t(u64, end, (1ULL << 32) - I915_GTT_PAGE_SIZE); + * + * so nothing will ever touch the top page. + */ + bo->bo.flags &= ~EXEC_OBJECT_SUPPORTS_48B_ADDRESS; + /* Set the exists last because it may be read by other threads */ __sync_synchronize(); bo->exists = true; |