net: ethernet: mtk_eth_soc: reduce MDIO bus access latency

usleep_range often ends up sleeping much longer than the 10-20us provided
as a range here. This causes significant latency in mdio bus acceses,
which easily adds multiple seconds to the boot time on MT7621 when polling
DSA slave ports.
Use cond_resched instead of usleep_range, since the MDIO access does not
take much time

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Felix Fietkau 2021-04-22 22:20:58 -07:00 committed by David S. Miller
parent c30c4a8273
commit 3630d519d7
1 changed files with 1 additions and 1 deletions

View File

@ -86,7 +86,7 @@ static int mtk_mdio_busy_wait(struct mtk_eth *eth)
return 0;
if (time_after(jiffies, t_start + PHY_IAC_TIMEOUT))
break;
usleep_range(10, 20);
cond_resched();
}
dev_err(eth->dev, "mdio: MDIO timeout\n");