netdev - [PATCH 3/5] tc35815: Increase timeout for mdio

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1249569709-21403-3-git-send-email-anemo@mba.ocn.ne.jp>
Date:	Thu,  6 Aug 2009 23:41:47 +0900
From:	Atsushi Nemoto <anemo@....ocn.ne.jp>
To:	netdev@...r.kernel.org
Cc:	David Miller <davem@...emloft.net>,
	Ralf Roesch <ralf.roesch@...gmbh.de>
Subject: [PATCH 3/5] tc35815: Increase timeout for mdio

The current timeout value is too short for very high-load condition
which jiffies might jump up in busy-loop.
Also add minimum delay before checking completion of MDIO.

Signed-off-by: Atsushi Nemoto <anemo@....ocn.ne.jp>
---
 drivers/net/tc35815.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/tc35815.c b/drivers/net/tc35815.c
index 801d201..1adb150 100644
--- a/drivers/net/tc35815.c
+++ b/drivers/net/tc35815.c
@@ -594,9 +594,10 @@ static int tc_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 	struct net_device *dev = bus->priv;
 	struct tc35815_regs __iomem *tr =
 		(struct tc35815_regs __iomem *)dev->base_addr;
-	unsigned long timeout = jiffies + 10;
+	unsigned long timeout = jiffies + HZ;
 
 	tc_writel(MD_CA_Busy | (mii_id << 5) | (regnum & 0x1f), &tr->MD_CA);
+	udelay(12); /* it takes 32 x 400ns at least */
 	while (tc_readl(&tr->MD_CA) & MD_CA_Busy) {
 		if (time_after(jiffies, timeout))
 			return -EIO;
@@ -610,11 +611,12 @@ static int tc_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 val)
 	struct net_device *dev = bus->priv;
 	struct tc35815_regs __iomem *tr =
 		(struct tc35815_regs __iomem *)dev->base_addr;
-	unsigned long timeout = jiffies + 10;
+	unsigned long timeout = jiffies + HZ;
 
 	tc_writel(val, &tr->MD_Data);
 	tc_writel(MD_CA_Busy | MD_CA_Wr | (mii_id << 5) | (regnum & 0x1f),
 		  &tr->MD_CA);
+	udelay(12); /* it takes 32 x 400ns at least */
 	while (tc_readl(&tr->MD_CA) & MD_CA_Busy) {
 		if (time_after(jiffies, timeout))
 			return -EIO;
-- 
1.5.6.5

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html