diff mbox series

cxgb3: Remove useless DMA-32 fallback configuration

Message ID a0e2539aefb0034091aca02c98440ea9459f1258.1641736234.git.christophe.jaillet@wanadoo.fr (mailing list archive)
State Accepted
Commit 544bdad074945c341b03a43f98efcc4e067d7b1b
Delegated to: Netdev Maintainers
Headers show
Series cxgb3: Remove useless DMA-32 fallback configuration | expand

Checks

Context Check Description
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix warning Target tree name not specified in the subject
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1 this patch: 1
netdev/cc_maintainers success CCed 4 of 4 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1 this patch: 1
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 29 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/tree_selection success Guessing tree name failed - patch did not apply

Commit Message

Christophe JAILLET Jan. 9, 2022, 1:51 p.m. UTC 
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.

So, if dma_set_mask_and_coherent() succeeds, 'pci_using_dac' is known to be
1.

Simplify code and remove some dead code accordingly.

[1]: https://lkml.org/lkml/2021/6/7/398

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Jan. 10, 2022, 1 a.m. UTC | #1 
Hello:

This patch was applied to netdev/net-next.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Sun,  9 Jan 2022 14:51:22 +0100 you 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.
> 
> So, if dma_set_mask_and_coherent() succeeds, 'pci_using_dac' is known to be
> 1.
> 
> [...]

Here is the summary with links:
  - cxgb3: Remove useless DMA-32 fallback configuration
    https://git.kernel.org/netdev/net-next/c/544bdad07494

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
index e2637bd2f423..63521312cb90 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
@@ -3204,7 +3204,7 @@  static void cxgb3_init_iscsi_mac(struct net_device *dev)
 			NETIF_F_IPV6_CSUM | NETIF_F_HIGHDMA)
 static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
-	int i, err, pci_using_dac = 0;
+	int i, err;
 	resource_size_t mmio_start, mmio_len;
 	const struct adapter_info *ai;
 	struct adapter *adapter = NULL;
@@ -3231,9 +3231,8 @@  static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto out_disable_device;
 	}
 
-	if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
-		pci_using_dac = 1;
-	} else if ((err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32))) != 0) {
+	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (err) {
 		dev_err(&pdev->dev, "no usable DMA configuration\n");
 		goto out_release_regions;
 	}
@@ -3309,8 +3308,8 @@  static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		netdev->features |= netdev->hw_features |
 				    NETIF_F_HW_VLAN_CTAG_TX;
 		netdev->vlan_features |= netdev->features & VLAN_FEAT;
-		if (pci_using_dac)
-			netdev->features |= NETIF_F_HIGHDMA;
+
+		netdev->features |= NETIF_F_HIGHDMA;
 
 		netdev->netdev_ops = &cxgb_netdev_ops;
 		netdev->ethtool_ops = &cxgb_ethtool_ops;