[PATCH 5.10 110/129] net: ethernet: stmmac: fix write to sgmii_adapter_base

Greg Kroah-Hartman
2022-05-04T17:04:54Z

From: Dinh Nguyen <dinguyen@kernel.org>

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@vger.kernel.org
Fixes: a6aaa0032424 ("net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link")
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20220420152345.27415-1-dinguyen@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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)