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From: Deepak Sikri <deepak.sikri@st.com>
To: <peppe.cavallaro@st.com>
Cc: <spear-devel@list.st.com>, <netdev@vger.kernel.org>,
	Deepak Sikri <deepak.sikri@st.com>
Subject: [PATCH 6/6] stmmac: Replace infinite loops by timeouts in mdio r/w
Date: Fri, 2 Mar 2012 18:25:28 +0530	[thread overview]
Message-ID: <1330692928-30330-7-git-send-email-deepak.sikri@st.com> (raw)
In-Reply-To: <1330692928-30330-6-git-send-email-deepak.sikri@st.com>

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 These infinite waits have been replaced by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 <deepak.sikri@st.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c |   30 ++++++++++++++++-----
 1 files changed, 23 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..b6a6fb2 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -34,6 +34,20 @@
 #define MII_BUSY 0x00000001
 #define MII_WRITE 0x00000002
 
+static int stmmac_mdio_busy_wait(unsigned long ioaddr, unsigned int mii_addr)
+{
+	unsigned long finish = jiffies + 3 * HZ;
+
+	do {
+		if (readl(ioaddr + mii_addr) & MII_BUSY)
+			cpu_relax();
+		else
+			return 0;
+	} while (!time_after_eq(jiffies, finish));
+
+	return -EBUSY;
+}
+
 /**
  * stmmac_mdio_read
  * @bus: points to the mii_bus structure
@@ -56,9 +70,13 @@ 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 +106,16 @@ 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);
 }
 
 /**
-- 
1.6.0.2

  reply	other threads:[~2012-03-02 12:56 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-03-02 12:55 [PATCH 0/6] stmmac: Driver Updates Deepak Sikri
2012-03-02 12:55 ` [PATCH 1/6] stmmac: Define CSUM offload engine Types Deepak Sikri
2012-03-02 12:55   ` [PATCH 2/6] stmmac: Define MDC clock selection macros Deepak Sikri
2012-03-02 12:55     ` [PATCH 3/6] stmmac: Add support for CPU freq notifiers Deepak Sikri
2012-03-02 12:55       ` [PATCH 4/6] stmmac: Update stmmac descriptor checks for stmmac core prior to Rev-3.5 Deepak Sikri
2012-03-02 12:55         ` [PATCH 5/6] stmmac: configure burst related GMAC DMA parameters Deepak Sikri
2012-03-02 12:55           ` Deepak Sikri [this message]
2012-03-06  7:55             ` [PATCH 6/6] stmmac: Replace infinite loops by timeouts in mdio r/w Giuseppe CAVALLARO
2012-03-05  1:52           ` [PATCH 5/6] stmmac: configure burst related GMAC DMA parameters David Miller
2012-03-07  5:39             ` deepaksi
2012-03-06  7:43           ` Giuseppe CAVALLARO
2012-03-07  6:18             ` deepaksi
2012-03-05  1:51         ` [PATCH 4/6] stmmac: Update stmmac descriptor checks for stmmac core prior to Rev-3.5 David Miller
2012-03-05  4:01           ` Shiraz Hashim
2012-03-05  4:59             ` David Miller
2012-03-07  8:26           ` deepaksi
2012-03-06  7:10         ` Giuseppe CAVALLARO
2012-03-07  8:25           ` deepaksi
2012-03-07  8:45             ` Giuseppe CAVALLARO
2012-03-05  1:50       ` [PATCH 3/6] stmmac: Add support for CPU freq notifiers David Miller
2012-03-07  7:18         ` deepaksi
2012-03-05 15:05       ` Giuseppe CAVALLARO
2012-03-06  8:04         ` Giuseppe CAVALLARO
2012-03-07  8:28           ` deepaksi
2012-03-07  7:17         ` deepaksi
2012-03-05 14:34     ` [PATCH 2/6] stmmac: Define MDC clock selection macros Giuseppe CAVALLARO
2012-03-07  6:55       ` deepaksi
2012-03-07  7:19         ` Giuseppe CAVALLARO
2012-03-07  8:30           ` deepaksi
2012-03-05 14:13   ` [PATCH 1/6] stmmac: Define CSUM offload engine Types Giuseppe CAVALLARO
2012-03-07  6:50     ` deepaksi
2012-03-05 15:31 ` [PATCH 0/6] stmmac: Driver Updates Giuseppe CAVALLARO

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