Re: [PATCH V3] dmaengine: sprd: add dma mask interface in probe

From: Baolin Wang
Date: Wed Sep 20 2023 - 04:12:30 EST




On 9/19/2023 3:38 PM, Kaiwei Liu wrote:
In the probe of DMA, the default addressing range is 32 bits,
while the actual DMA hardware addressing range used is 36 bits.
So add dma_set_mask_and_coherent function to match DMA
addressing range.

Signed-off-by: Kaiwei Liu <kaiwei.liu@xxxxxxxxxx>

LGTM.
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>

---
Change in V2:
-Change subject line.
Change in V3:
-Modify error message to make it more readable.
---
drivers/dma/sprd-dma.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index 20c3cb1ef2f5..c371ce405f1d 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -1115,6 +1115,15 @@ static int sprd_dma_probe(struct platform_device *pdev)
u32 chn_count;
int ret, i;
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(36));
+ if (ret) {
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+ if (ret) {
+ dev_err(&pdev->dev, "unable to set coherent mask to 32\n");
+ return ret;
+ }
+ }
+
/* Parse new and deprecated dma-channels properties */
ret = device_property_read_u32(&pdev->dev, "dma-channels", &chn_count);
if (ret)