diff options
| author |   Herve Codina <herve.codina@bootlin.com> | 2021-10-08 12:34:37 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2021-10-08 16:22:38 +0100 |
| commit | 075da584bae2da6a37428d59a477b6bdad430ac3 (patch) | |
| tree | 5c0300839c82134246d9d0440a120abcfda9cd95 /drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c | |
| parent | mptcp: fix possible stall on recvmsg() (diff) | |
| download | linux-dev-075da584bae2da6a37428d59a477b6bdad430ac3.tar.xz linux-dev-075da584bae2da6a37428d59a477b6bdad430ac3.zip | |
net: stmmac: fix get_hw_feature() on old hardware
Some old IPs do not provide the hardware feature register.
On these IPs, this register is read 0x00000000.
In old driver version, this feature was handled but a regression came
with the commit f10a6a3541b4 ("stmmac: rework get_hw_feature function").
Indeed, this commit removes the return value in dma->get_hw_feature().
This return value was used to indicate the validity of retrieved
information and used later on in stmmac_hw_init() to override
priv->plat data if this hardware feature were valid.
This patch restores the return code in ->get_hw_feature() in order
to indicate the hardware feature validity and override priv->plat
data only if this hardware feature is valid.
Fixes: f10a6a3541b4 ("stmmac: rework get_hw_feature function")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c')
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c index 90383abafa66..f5581db0ba9b 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c @@ -218,11 +218,18 @@ static void dwmac1000_dump_dma_regs(void __iomem *ioaddr, u32 *reg_space) readl(ioaddr + DMA_BUS_MODE + i * 4); } -static void dwmac1000_get_hw_feature(void __iomem *ioaddr, - struct dma_features *dma_cap) +static int dwmac1000_get_hw_feature(void __iomem *ioaddr, + struct dma_features *dma_cap) { u32 hw_cap = readl(ioaddr + DMA_HW_FEATURE); + if (!hw_cap) { + /* 0x00000000 is the value read on old hardware that does not + * implement this register + */ + return -EOPNOTSUPP; + } + dma_cap->mbps_10_100 = (hw_cap & DMA_HW_FEAT_MIISEL); dma_cap->mbps_1000 = (hw_cap & DMA_HW_FEAT_GMIISEL) >> 1; dma_cap->half_duplex = (hw_cap & DMA_HW_FEAT_HDSEL) >> 2; @@ -252,6 +259,8 @@ static void dwmac1000_get_hw_feature(void __iomem *ioaddr, dma_cap->number_tx_channel = (hw_cap & DMA_HW_FEAT_TXCHCNT) >> 22; /* Alternate (enhanced) DESC mode */ dma_cap->enh_desc = (hw_cap & DMA_HW_FEAT_ENHDESSEL) >> 24; + + return 0; } static void dwmac1000_rx_watchdog(void __iomem *ioaddr, u32 riwt, |