ag71xx: fix a memory corruption bug that happens if you flood the interface with...

fixes boot time crashes under load reported by matteo

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@22054 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c
index a57b6d4..9fd4152 100644 (file)
--- a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c
+++ b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c
@@ -454,6 +454,12 @@ static void ag71xx_dma_reset(struct ag71xx *ag)
        ag71xx_wr(ag, AG71XX_REG_RX_CTRL, 0);
        ag71xx_wr(ag, AG71XX_REG_TX_CTRL, 0);
 
+       /*
+        * give the hardware some time to really stop all rx/tx activity
+        * clearing the descriptors too early causes random memory corruption
+        */
+       mdelay(1);
+
        /* clear descriptor addresses */
        ag71xx_wr(ag, AG71XX_REG_TX_DESC, 0);
        ag71xx_wr(ag, AG71XX_REG_RX_DESC, 0);