Commit 8fb2c796 authored by Yoshihiro Shimoda's avatar Yoshihiro Shimoda Committed by Greg Kroah-Hartman

net: sh_eth: fix mdio access in sh_eth_close() for R-Car Gen2 and RZ/A1 SoCs

[ Upstream commit 315ca92dd863fecbffc0bb52ae0ac11e0398726a ]

The sh_eth_close() resets the MAC and then calls phy_stop()
so that mdio read access result is incorrect without any error
according to kernel trace like below:

ifconfig-216   [003] .n..   109.133124: mdio_access: ee700000.ethernet-ffffffff read  phy:0x01 reg:0x00 val:0xffff

According to the hardware manual, the RMII mode should be set to 1
before operation the Ethernet MAC. However, the previous code was not
set to 1 after the driver issued the soft_reset in sh_eth_dev_exit()
so that the mdio read access result seemed incorrect. To fix the issue,
this patch adds a condition and set the RMII mode register in
sh_eth_dev_exit() for R-Car Gen2 and RZ/A1 SoCs.

Note that when I have tried to move the sh_eth_dev_exit() calling
after phy_stop() on sh_eth_close(), but it gets worse (kernel panic
happened and it seems that a register is accessed while the clock is
off).
Signed-off-by: 's avatarYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: 's avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: 's avatarSasha Levin <sashal@kernel.org>
parent 467f9026
......@@ -1588,6 +1588,10 @@ static void sh_eth_dev_exit(struct net_device *ndev)
sh_eth_get_stats(ndev);
mdp->cd->soft_reset(ndev);
/* Set the RMII mode again if required */
if (mdp->cd->rmiimode)
sh_eth_write(ndev, 0x1, RMIIMODE);
/* Set MAC address again */
update_mac_address(ndev);
}
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment