Commit 64953720 authored by Christophe JAILLET's avatar Christophe JAILLET Committed by Tony Nguyen
Browse files

ixgb: Remove useless DMA-32 fallback configuration 

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: default avatarChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarAlexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent e2cf0765

drivers/net/ethernet/intel/ixgb/ixgb_main.c

+5 −14
Original line number Diff line number Diff line
@@ -361,7 +361,6 @@ ixgb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 
	struct net_device *netdev = NULL;

	struct ixgb_adapter *adapter;

	static int cards_found = 0;

	int pci_using_dac;

	u8 addr[ETH_ALEN];

	int i;

	int err;
@@ -370,17 +369,11 @@ ixgb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 
	if (err)

		return err;



	pci_using_dac = 0;

	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));

	if (!err) {

		pci_using_dac = 1;

	} else {

		err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));

	if (err) {

		pr_err("No usable DMA configuration, aborting\n");

		goto err_dma_mask;

	}

	}



	err = pci_request_regions(pdev, ixgb_driver_name);

	if (err)
@@ -444,10 +437,8 @@ ixgb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 
			   NETIF_F_HW_VLAN_CTAG_FILTER;

	netdev->hw_features |= NETIF_F_RXCSUM;



	if (pci_using_dac) {

	netdev->features |= NETIF_F_HIGHDMA;

	netdev->vlan_features |= NETIF_F_HIGHDMA;

	}



	/* MTU range: 68 - 16114 */

	netdev->min_mtu = ETH_MIN_MTU;