From: Dinh Nguyen <dinguyen@xxxxxxxxxx> commit 5fd1fe4807f91ea0cca043114d929faa11bd4190 upstream. I made a mistake with the commit a6aaa0032424 ("net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link"). I should have tested against both scenario of having a SGMII interface and one without. Without the SGMII PCS TSE adpater, the sgmii_adapter_base address is NULL, thus a write to this address will fail. Cc: stable@xxxxxxxxxxxxxxx Fixes: a6aaa0032424 ("net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link") Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220420152345.27415-1-dinguyen@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c @@ -65,8 +65,9 @@ static void socfpga_dwmac_fix_mac_speed( struct phy_device *phy_dev = ndev->phydev; u32 val; - writew(SGMII_ADAPTER_DISABLE, - sgmii_adapter_base + SGMII_ADAPTER_CTRL_REG); + if (sgmii_adapter_base) + writew(SGMII_ADAPTER_DISABLE, + sgmii_adapter_base + SGMII_ADAPTER_CTRL_REG); if (splitter_base) { val = readl(splitter_base + EMAC_SPLITTER_CTRL_REG); @@ -88,10 +89,11 @@ static void socfpga_dwmac_fix_mac_speed( writel(val, splitter_base + EMAC_SPLITTER_CTRL_REG); } - writew(SGMII_ADAPTER_ENABLE, - sgmii_adapter_base + SGMII_ADAPTER_CTRL_REG); - if (phy_dev) + if (phy_dev && sgmii_adapter_base) { + writew(SGMII_ADAPTER_ENABLE, + sgmii_adapter_base + SGMII_ADAPTER_CTRL_REG); tse_pcs_fix_mac_speed(&dwmac->pcs, phy_dev, speed); + } } static int socfpga_dwmac_parse_data(struct socfpga_dwmac *dwmac, struct device *dev)