[PATCH 06/10] stmmac: Replace infinite loops by timeouts in mdio r/w
flat view
STALE5307d
REVIEWED: 1 (0M)
From: Giuseppe CAVALLARO <hidden>
Date: 2012-03-23 09:09:34
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds
1 review trailer.
From: Deepak SIKRI <redacted> This patch removes the infinite waits from the mdio read and write interfaces. These infinite waits have been replaced by the timeout handling. In case if a time out occurs, an error is returned. Signed-off-by: Deepak Sikri <redacted> Acked-by: Giuseppe Cavallaro <redacted> --- drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c | 32 ++++++++++++++++---- 1 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index 7319532..83292f4 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c@@ -34,6 +34,22 @@ #define MII_BUSY 0x00000001 #define MII_WRITE 0x00000002 +static int stmmac_mdio_busy_wait(void __iomem *ioaddr, unsigned int mii_addr) +{ + unsigned long curr; + unsigned long finish = jiffies + 3 * HZ; + + do { + curr = jiffies; + if (readl(ioaddr + mii_addr) & MII_BUSY) + cpu_relax(); + else + return 0; + } while (!time_after_eq(curr, finish)); + + return -EBUSY; +} + /** * stmmac_mdio_read * @bus: points to the mii_bus structure
@@ -56,9 +72,13 @@ static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg) ((phyreg << 6) & (0x000007C0))); regValue |= MII_BUSY | ((priv->plat->clk_csr & 7) << 2); - do {} while (((readl(priv->ioaddr + mii_address)) & MII_BUSY) == 1); + if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) + return -EBUSY; + writel(regValue, priv->ioaddr + mii_address); - do {} while (((readl(priv->ioaddr + mii_address)) & MII_BUSY) == 1); + + if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) + return -EBUSY; /* Read the data from the MII data register */ data = (int)readl(priv->ioaddr + mii_data);
@@ -88,18 +108,16 @@ static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg, value |= MII_BUSY | ((priv->plat->clk_csr & 7) << 2); - /* Wait until any existing MII operation is complete */ - do {} while (((readl(priv->ioaddr + mii_address)) & MII_BUSY) == 1); + if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) + return -EBUSY; /* Set the MII address register to write */ writel(phydata, priv->ioaddr + mii_data); writel(value, priv->ioaddr + mii_address); /* Wait until any existing MII operation is complete */ - do {} while (((readl(priv->ioaddr + mii_address)) & MII_BUSY) == 1); - - return 0; + return stmmac_mdio_busy_wait(priv->ioaddr, mii_address); } /**
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1.7.4.4