Commit fea89930 authored by Christophe JAILLET's avatar Christophe JAILLET Committed by Tony Nguyen
Browse files

igc: 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>
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent 9c3e54a6

drivers/net/ethernet/intel/igc/igc_main.c

+6 −13
Original line number Diff line number Diff line
@@ -6251,24 +6251,18 @@ static int igc_probe(struct pci_dev *pdev, 
	struct net_device *netdev;

	struct igc_hw *hw;

	const struct igc_info *ei = igc_info_tbl[ent->driver_data];

	int err, pci_using_dac;

	int err;



	err = pci_enable_device_mem(pdev);

	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) {

		dev_err(&pdev->dev,

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

		goto err_dma;

	}

	}



	err = pci_request_mem_regions(pdev, igc_driver_name);

	if (err)
@@ -6367,7 +6361,6 @@ static int igc_probe(struct pci_dev *pdev, 
	netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX;

	netdev->hw_features |= netdev->features;



	if (pci_using_dac)

	netdev->features |= NETIF_F_HIGHDMA;



	netdev->vlan_features |= netdev->features | NETIF_F_TSO_MANGLEID;