[PATCH v2] drm: mediatek: change the variable type of rdma threshold

From: Bibby Hsieh
Date: Fri May 19 2017 - 05:57:37 EST


For some greater resolution, the rdma threshold
variable will overflow.

Signed-off-by: Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_disp_rdma.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
index 0df05f9..9afdcd7 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_rdma.c
@@ -37,7 +37,7 @@
#define DISP_REG_RDMA_FIFO_CON 0x0040
#define RDMA_FIFO_UNDERFLOW_EN BIT(31)
#define RDMA_FIFO_PSEUDO_SIZE(bytes) (((bytes) / 16) << 16)
-#define RDMA_OUTPUT_VALID_FIFO_THRESHOLD(bytes) ((bytes) / 16)
+#define RDMA_OUTPUT_VALID_FIFO_THRESHOLD(bytes) (((bytes) / 16) & 0x3ff)

/**
* struct mtk_disp_rdma - DISP_RDMA driver structure
@@ -109,7 +109,7 @@ static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned int width,
unsigned int height, unsigned int vrefresh,
unsigned int bpc)
{
- unsigned int threshold;
+ unsigned long long threshold;
unsigned int reg;

rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_0, 0xfff, width);
@@ -121,7 +121,8 @@ static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned int width,
* output threshold to 6 microseconds with 7/6 overhead to
* account for blanking, and with a pixel depth of 4 bytes:
*/
- threshold = width * height * vrefresh * 4 * 7 / 1000000;
+ threshold = (unsigned long long)width * height * vrefresh *
+ 4 * 7 / 1000000;
reg = RDMA_FIFO_UNDERFLOW_EN |
RDMA_FIFO_PSEUDO_SIZE(SZ_8K) |
RDMA_OUTPUT_VALID_FIFO_THRESHOLD(threshold);
--
1.9.1