[PATCH] cxgb4: Remove useless DMA-32 fallback configuration

From: Christophe JAILLET
Date: Sun Jan 09 2022 - 08:53:36 EST


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, 'highdma' is known to be true.

Simplify code and remove some dead code accordingly.

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

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 17 +++++------------
1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index dde1cf51d0ab..0c78c0db8937 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -6608,7 +6608,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
static int adap_idx = 1;
int s_qpp, qpp, num_seg;
struct port_info *pi;
- bool highdma = false;
enum chip_type chip;
void __iomem *regs;
int func, chip_ver;
@@ -6687,14 +6686,10 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
return 0;
}

- if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
- highdma = true;
- } else {
- err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
- if (err) {
- dev_err(&pdev->dev, "no usable DMA configuration\n");
- goto out_free_adapter;
- }
+ 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_free_adapter;
}

pci_enable_pcie_error_reporting(pdev);
@@ -6823,7 +6818,7 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
NETIF_F_RXCSUM | NETIF_F_RXHASH | NETIF_F_GRO |
NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX |
- NETIF_F_HW_TC | NETIF_F_NTUPLE;
+ NETIF_F_HW_TC | NETIF_F_NTUPLE | NETIF_F_HIGHDMA;

if (chip_ver > CHELSIO_T5) {
netdev->hw_enc_features |= NETIF_F_IP_CSUM |
@@ -6841,8 +6836,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
netdev->udp_tunnel_nic_info = &cxgb_udp_tunnels;
}

- if (highdma)
- netdev->hw_features |= NETIF_F_HIGHDMA;
netdev->features |= netdev->hw_features;
netdev->vlan_features = netdev->features & VLAN_FEAT;
#if IS_ENABLED(CONFIG_CHELSIO_TLS_DEVICE)
--
2.32.0