the orginal formula will caused rdma fifo threshold config overflow
and no one could come out a solution for all SoC,
set threshold to 70% of max fifo size to make sure it will
not overflow, and 70% is a empirical vlaue

Signed-off-by: Yongqiang Niu <yongqiang....@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_rdma.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c 
b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
index f123fc0..f1f6a2e 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
@@ -164,10 +164,10 @@ void mtk_rdma_config(struct device *dev, unsigned int 
width,
        /*
         * Enable FIFO underflow since DSI and DPI can't be blocked.
         * Keep the FIFO pseudo size reset default of 8 KiB. Set the
-        * output threshold to 6 microseconds with 7/6 overhead to
-        * account for blanking, and with a pixel depth of 4 bytes:
+        * output threshold to 70% of max fifo size to make sure the
+        * threhold will not overflow
         */
-       threshold = width * height * vrefresh * 4 * 7 / 1000000;
+       threshold = rdma_fifo_size * 7 / 10;
        reg = RDMA_FIFO_UNDERFLOW_EN |
              RDMA_FIFO_PSEUDO_SIZE(rdma_fifo_size) |
              RDMA_OUTPUT_VALID_FIFO_THRESHOLD(threshold);
-- 
1.8.1.1.dirty

Reply via email to