dmaengine: idxd: Remove useless DMA-32 fallback configuration

[PATCH] dmaengine: idxd: Remove useless DMA-32 fallback configuration

Posted by Christophe JAILLET 4 years, 5 months ago

As stated in [1], dma_set_mask() with a 64-bit mask never fails if
dev->dma_mask is non-NULL.
So, if it fails, the 32 bits case will also fail for the same reason.

Simplify code and remove some dead code accordingly.

[1]: https://lore.kernel.org/linux-kernel/YL3vSPK5DXTNvgdx@infradead.org/#t

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/dma/idxd/init.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index 08a5f4310188..993a5dcca24f 100644
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -604,8 +604,6 @@ static int idxd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	dev_dbg(dev, "Set DMA masks\n");
 	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
-	if (rc)
-		rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 	if (rc)
 		goto err;
 
-- 
2.32.0

Re: [PATCH] dmaengine: idxd: Remove useless DMA-32 fallback configuration

Posted by Vinod Koul 4 years, 3 months ago

On 15-01-22, 08:24, Christophe JAILLET wrote:
> As stated in [1], dma_set_mask() with a 64-bit mask never fails if
> dev->dma_mask is non-NULL.
> So, if it fails, the 32 bits case will also fail for the same reason.
> 
> Simplify code and remove some dead code accordingly.

Applied, thanks

-- 
~Vinod

Re: [PATCH] dmaengine: idxd: Remove useless DMA-32 fallback configuration

Posted by Dave Jiang 4 years, 5 months ago

On 1/15/2022 12:24 AM, Christophe JAILLET wrote:
> As stated in [1], dma_set_mask() with a 64-bit mask never fails if
> dev->dma_mask is non-NULL.
> So, if it fails, the 32 bits case will also fail for the same reason.
>
> Simplify code and remove some dead code accordingly.
>
> [1]: https://lore.kernel.org/linux-kernel/YL3vSPK5DXTNvgdx@infradead.org/#t
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Acked-by: Dave Jiang <dave.jiang@intel.com>

Thanks.

> ---
>   drivers/dma/idxd/init.c | 2 --
>   1 file changed, 2 deletions(-)
>
> diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
> index 08a5f4310188..993a5dcca24f 100644
> --- a/drivers/dma/idxd/init.c
> +++ b/drivers/dma/idxd/init.c
> @@ -604,8 +604,6 @@ static int idxd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>   
>   	dev_dbg(dev, "Set DMA masks\n");
>   	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> -	if (rc)
> -		rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>   	if (rc)
>   		goto err;
>