01796e87b1
It seems that there are maximum timings for mdio accesses that can be hit when the system is under load and the thread is scheduled during a read or write access. Since there is no way of knowing if this happens as there is not even a parity bit, try to work around it by disabling interrupts during any gpio-mdio accesses. Performance impact seems to be neglectable, as mdio accesses are not that often. Hopefully fixes #19500. Signed-off-by: Jonas Gorski <jogo@openwrt.org> SVN-Revision: 46012
61 lines
1.6 KiB
Diff
61 lines
1.6 KiB
Diff
From 66e584435ac0de6e0abeb6d7166fe4fe25d6bb73 Mon Sep 17 00:00:00 2001
|
|
From: Jonas Gorski <jogo@openwrt.org>
|
|
Date: Tue, 16 Jun 2015 13:15:08 +0200
|
|
Subject: [PATCH] phy/mdio-bitbang: prevent rescheduling during command
|
|
|
|
It seems some phys have some maximum timings for accessing the MDIO line,
|
|
resulting in bit errors under cpu stress. Prevent this from happening by
|
|
disabling interrupts when sending commands.
|
|
|
|
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
|
|
---
|
|
drivers/net/phy/mdio-bitbang.c | 9 +++++++++
|
|
1 file changed, 9 insertions(+)
|
|
|
|
--- a/drivers/net/phy/mdio-bitbang.c
|
|
+++ b/drivers/net/phy/mdio-bitbang.c
|
|
@@ -17,6 +17,7 @@
|
|
* kind, whether express or implied.
|
|
*/
|
|
|
|
+#include <linux/irqflags.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mdio-bitbang.h>
|
|
#include <linux/types.h>
|
|
@@ -156,7 +157,9 @@ static int mdiobb_read(struct mii_bus *b
|
|
{
|
|
struct mdiobb_ctrl *ctrl = bus->priv;
|
|
int ret, i;
|
|
+ long flags;
|
|
|
|
+ local_irq_save(flags);
|
|
if (reg & MII_ADDR_C45) {
|
|
reg = mdiobb_cmd_addr(ctrl, phy, reg);
|
|
mdiobb_cmd(ctrl, MDIO_C45_READ, phy, reg);
|
|
@@ -169,13 +172,17 @@ static int mdiobb_read(struct mii_bus *b
|
|
|
|
ret = mdiobb_get_num(ctrl, 16);
|
|
mdiobb_get_bit(ctrl);
|
|
+ local_irq_restore(flags);
|
|
+
|
|
return ret;
|
|
}
|
|
|
|
static int mdiobb_write(struct mii_bus *bus, int phy, int reg, u16 val)
|
|
{
|
|
struct mdiobb_ctrl *ctrl = bus->priv;
|
|
+ long flags;
|
|
|
|
+ local_irq_save(flags);
|
|
if (reg & MII_ADDR_C45) {
|
|
reg = mdiobb_cmd_addr(ctrl, phy, reg);
|
|
mdiobb_cmd(ctrl, MDIO_C45_WRITE, phy, reg);
|
|
@@ -190,6 +197,8 @@ static int mdiobb_write(struct mii_bus *
|
|
|
|
ctrl->ops->set_mdio_dir(ctrl, 0);
|
|
mdiobb_get_bit(ctrl);
|
|
+ local_irq_restore(flags);
|
|
+
|
|
return 0;
|
|
}
|
|
|