On 11/04/18 15:44, Pierre-Yves MORDRET wrote:
Both buffer Transfer Length (TLEN if any) and transfer size have to be
aligned on burst size (burst beats*bus width).
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mord...@st.com>
---
Version history:
v1:
* Initial
v2:
---
---
drivers/dma/stm32-mdma.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index daa1602..fbcffa2 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -413,7 +413,7 @@ static u32 stm32_mdma_get_best_burst(u32 buf_len, u32 tlen,
u32 max_burst,
u32 best_burst = max_burst;
u32 burst_len = best_burst * width;
- while ((burst_len > 0) && (tlen % burst_len)) {
+ while ((burst_len > 0) && (((tlen | buf_len) & (burst_len - 1)) != 0)) {
best_burst = best_burst >> 1;
burst_len = best_burst * width;
}
FWIW, doesn't that whole loop come down to just:
burst_len = min(ffs(tlen | buf_len), max_burst * width);
?
Robin.
