[PATCH net 1/2] net: cadence: macb: Disable USRIO register on some platforms
From: Neil Armstrong <hidden>
Date: 2015-12-07 11:00:09
Also in:
linux-devicetree, lkml
Subsystem:
atmel macb ethernet driver, networking drivers, the rest · Maintainers:
Théo Lebrun, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
On some platforms, the macb integration does not use the USRIO register to configure the (R)MII port and clocks. When the register is not implemented and the MACB error signal is connected to the bus error, reading or writing to the USRIO register can trigger some Imprecise External Aborts on ARM platforms. --- drivers/net/ethernet/cadence/macb.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index 169059c..3897620 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c@@ -2122,7 +2122,9 @@ static void macb_get_regs(struct net_device *dev, struct ethtool_regs *regs, regs_buff[10] = macb_tx_dma(&bp->queues[0], tail); regs_buff[11] = macb_tx_dma(&bp->queues[0], head); - regs_buff[12] = macb_or_gem_readl(bp, USRIO); + if (!of_property_read_bool(bp->pdev->dev.of_node, "no-usrio")) { + regs_buff[12] = macb_or_gem_readl(bp, USRIO); + } if (macb_is_gem(bp)) { regs_buff[13] = gem_readl(bp, DMACFG); }
@@ -2401,19 +2403,22 @@ static int macb_init(struct platform_device *pdev) dev->hw_features &= ~NETIF_F_SG; dev->features = dev->hw_features; - val = 0; - if (bp->phy_interface == PHY_INTERFACE_MODE_RGMII) - val = GEM_BIT(RGMII); - else if (bp->phy_interface == PHY_INTERFACE_MODE_RMII && - (bp->caps & MACB_CAPS_USRIO_DEFAULT_IS_MII)) - val = MACB_BIT(RMII); - else if (!(bp->caps & MACB_CAPS_USRIO_DEFAULT_IS_MII)) - val = MACB_BIT(MII); + /* Some platform do not implement the USRIO register */ + if (!of_property_read_bool(pdev->dev.of_node, "no-usrio")) { + val = 0; + if (bp->phy_interface == PHY_INTERFACE_MODE_RGMII) + val = GEM_BIT(RGMII); + else if (bp->phy_interface == PHY_INTERFACE_MODE_RMII && + (bp->caps & MACB_CAPS_USRIO_DEFAULT_IS_MII)) + val = MACB_BIT(RMII); + else if (!(bp->caps & MACB_CAPS_USRIO_DEFAULT_IS_MII)) + val = MACB_BIT(MII); - if (bp->caps & MACB_CAPS_USRIO_HAS_CLKEN) - val |= MACB_BIT(CLKEN); + if (bp->caps & MACB_CAPS_USRIO_HAS_CLKEN) + val |= MACB_BIT(CLKEN); - macb_or_gem_writel(bp, USRIO, val); + macb_or_gem_writel(bp, USRIO, val); + } /* Set MII management clock divider */ val = macb_mdc_clk_div(bp);
--
1.9.1