2 files changed, 13 insertions, 4 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_gart.c b/drivers/gpu/drm/radeon/radeon_gart.c
index 59d44937dd9f..84b648a7ddd8 100644
--- a/drivers/gpu/drm/radeon/radeon_gart.c
+++ b/drivers/gpu/drm/radeon/radeon_gart.c
@@ -289,8 +289,9 @@ int radeon_vm_manager_init(struct radeon_device *rdev)
         rdev->vm_manager.enabled = false;
 
         /* mark first vm as always in use, it's the system one */
+        /* allocate enough for 2 full VM pts */
         r = radeon_sa_bo_manager_init(rdev, &rdev->vm_manager.sa_manager,
-                                      rdev->vm_manager.max_pfn * 8,
+                                      rdev->vm_manager.max_pfn * 8 * 2,
                                       RADEON_GEM_DOMAIN_VRAM);
         if (r) {
                 dev_err(rdev->dev, "failed to allocate vm bo (%dKB)\n",
@@ -633,7 +634,15 @@ int radeon_vm_init(struct radeon_device *rdev, struct radeon_vm *vm)
         mutex_init(&vm->mutex);
         INIT_LIST_HEAD(&vm->list);
         INIT_LIST_HEAD(&vm->va);
-        vm->last_pfn = 0;
+        /* SI requires equal sized PTs for all VMs, so always set
+         * last_pfn to max_pfn.  cayman allows variable sized
+         * pts so we can grow then as needed.  Once we switch
+         * to two level pts we can unify this again.
+         */
+        if (rdev->family >= CHIP_TAHITI)
+                vm->last_pfn = rdev->vm_manager.max_pfn;
+        else
+                vm->last_pfn = 0;
         /* map the ib pool buffer at 0 in virtual address space, set
          * read only
          */
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index c7b61f16ecfd..0b0279291a73 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -2365,12 +2365,12 @@ int si_pcie_gart_enable(struct radeon_device *rdev)
         WREG32(0x15DC, 0);
 
         /* empty context1-15 */
-        /* FIXME start with 1G, once using 2 level pt switch to full
+        /* FIXME start with 4G, once using 2 level pt switch to full
          * vm size space
          */
         /* set vm size, must be a multiple of 4 */
         WREG32(VM_CONTEXT1_PAGE_TABLE_START_ADDR, 0);
-        WREG32(VM_CONTEXT1_PAGE_TABLE_END_ADDR, (1 << 30) / RADEON_GPU_PAGE_SIZE);
+        WREG32(VM_CONTEXT1_PAGE_TABLE_END_ADDR, rdev->vm_manager.max_pfn);
         for (i = 1; i < 16; i++) {
                 if (i < 8)
                         WREG32(VM_CONTEXT0_PAGE_TABLE_BASE_ADDR + (i << 2),