drm/radeon: update comments to clarify VM setup (v2)

The actual set up and assignment of VM page tables
is done on the fly in radeon_gart.c.

v2: update vm size comments

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
This commit is contained in:
Alex Deucher 2012-10-08 09:45:46 -04:00
parent 29dbe3bcd2
commit 23d4f1f246
3 changed files with 12 additions and 3 deletions

View file

@ -770,6 +770,10 @@ static int cayman_pcie_gart_enable(struct radeon_device *rdev)
WREG32(0x15DC, 0);
/* empty context1-7 */
/* Assign the pt base to something valid for now; the pts used for
* the VMs are determined by the application and setup and assigned
* on the fly in the vm part of radeon_gart.c
*/
for (i = 1; i < 8; i++) {
WREG32(VM_CONTEXT0_PAGE_TABLE_START_ADDR + (i << 2), 0);
WREG32(VM_CONTEXT0_PAGE_TABLE_END_ADDR + (i << 2), 0);

View file

@ -1018,6 +1018,10 @@ int radeon_device_init(struct radeon_device *rdev,
return r;
/* initialize vm here */
mutex_init(&rdev->vm_manager.lock);
/* Adjust VM size here.
* Currently set to 4GB ((1 << 20) 4k pages).
* Max GPUVM size for cayman and SI is 40 bits.
*/
rdev->vm_manager.max_pfn = 1 << 20;
INIT_LIST_HEAD(&rdev->vm_manager.lru_vm);

View file

@ -2407,12 +2407,13 @@ static int si_pcie_gart_enable(struct radeon_device *rdev)
WREG32(0x15DC, 0);
/* empty context1-15 */
/* 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, rdev->vm_manager.max_pfn);
/* Assign the pt base to something valid for now; the pts used for
* the VMs are determined by the application and setup and assigned
* on the fly in the vm part of radeon_gart.c
*/
for (i = 1; i < 16; i++) {
if (i < 8)
WREG32(VM_CONTEXT0_PAGE_TABLE_BASE_ADDR + (i << 2),