[PATCH net-next] amd-xgbe: Let OS arch support adjust DMA mask as needed

[PATCH net-next] amd-xgbe: Let OS arch support adjust DMA mask as needed

[Tom Lendacky]

Set the DMA mask to 64-bit and let the underlying arch support adjust
it as appropriate based on device tree DMA ranges, etc.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 drivers/net/ethernet/amd/xgbe/xgbe-main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-main.c b/drivers/net/ethernet/amd/xgbe/xgbe-main.c
index 32dd651..080c3a8 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-main.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-main.c
@@ -377,7 +377,7 @@ static int xgbe_probe(struct platform_device *pdev)
 	/* Set the DMA mask */
 	if (!dev->dma_mask)
 		dev->dma_mask = &dev->coherent_dma_mask;
-	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(40));
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
 	if (ret) {
 		dev_err(dev, "dma_set_mask_and_coherent failed\n");
 		goto err_io;

Re: [PATCH net-next] amd-xgbe: Let OS arch support adjust DMA mask as needed

[David Miller]

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: Tue, 20 Jan 2015 14:47:55 -0600

> Set the DMA mask to 64-bit and let the underlying arch support adjust
> it as appropriate based on device tree DMA ranges, etc.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>

That's not how this works.

The interface will fail if you ask for more bits than can be
supported, so you should pass in the amount of bits you actually need
but not more.

I'm not applying this.