[PATCH] drm/xe/vram: fix ccs offset calculation

[PATCH] drm/xe/vram: fix ccs offset calculation

[Matthew Auld]

Spec says SW is expected to round up to the nearest 128K, if not already
aligned. We are seeing the assert sometimes pop on BMG to tell us that
there is a hole between GSM and CCS, as well as popping other asserts
with having a vram size with strange alignment, which is likely caused
by misaligned offset here.

BSpec: 68023
Fixes: b5c2ca0372dc ("drm/xe/xe2hpg: Determine flat ccs offset for vram")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
Cc: Shuicheng Lin <shuicheng.lin@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: <stable@vger.kernel.org> # v6.10+
---
 drivers/gpu/drm/xe/xe_vram.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/xe/xe_vram.c b/drivers/gpu/drm/xe/xe_vram.c
index 7e765b1499b1..8e65cb4cc477 100644
--- a/drivers/gpu/drm/xe/xe_vram.c
+++ b/drivers/gpu/drm/xe/xe_vram.c
@@ -181,6 +181,7 @@ static inline u64 get_flat_ccs_offset(struct xe_gt *gt, u64 tile_size)
 
 		offset = offset_hi << 32; /* HW view bits 39:32 */
 		offset |= offset_lo << 6; /* HW view bits 31:6 */
+		offset = round_up(offset, SZ_128K); /* SW must round up to nearest 128K */
 		offset *= num_enabled; /* convert to SW view */
 
 		/* We don't expect any holes */
-- 
2.46.0