2023-08-07 06:15:40

by Kaiwei Liu

Subject: [PATCH 2/5] dma: add dma mask interface in probe

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 <[email protected]>
---
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..0e146550dfbb 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, "dma_set_mask_and_coherent failed\n");
+ return ret;
+ }
+ }
+
/* Parse new and deprecated dma-channels properties */
ret = device_property_read_u32(&pdev->dev, "dma-channels", &chn_count);
if (ret)
--
2.17.1

2023-08-07 08:18:36

by Baolin Wang

Subject: Re: [PATCH 2/5] dma: add dma mask interface in probe

On 8/7/2023 1:20 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 <[email protected]>
> ---
> 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..0e146550dfbb 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, "dma_set_mask_and_coherent failed\n");

The error message is not readable, may be something like below?
"unable to set coherent mask to 32\n"

The changes look good to me. Chunyan and Orson, please double check the
DMA mask?

> + return ret;
> + }
> + }
> +
> /* Parse new and deprecated dma-channels properties */
> ret = device_property_read_u32(&pdev->dev, "dma-channels", &chn_count);
> if (ret)