diff options
| author | Maxim Uvarov <muvarov@gmail.com> | 2017-08-10 10:47:46 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-08-12 00:23:59 +0300 |
| commit | 2e1c80847b9983a8c93a678f6de2dc3c42f19661 (patch) | |
| tree | c48837e059647422f9c99b320abda09d5b9f376e /drivers/net/ethernet/ti/davinci_mdio.c | |
| parent | 3a4487b88f9a4deaded65fed60135b06298b7990 (diff) | |
| download | linux-2e1c80847b9983a8c93a678f6de2dc3c42f19661.tar.xz | |
drivers: net: davinci_mdio: remove busy loop on wait user access
Polling 14 mdio devices on single mdio bus eats 30% of 1Ghz cpu time
due to busy loop in wait(). Add small delay to relax cpu.
Signed-off-by: Max Uvarov <muvarov@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/ti/davinci_mdio.c')
| -rw-r--r-- | drivers/net/ethernet/ti/davinci_mdio.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c index 33df340db1f1..611e7cc5f07b 100644 --- a/drivers/net/ethernet/ti/davinci_mdio.c +++ b/drivers/net/ethernet/ti/davinci_mdio.c @@ -198,8 +198,10 @@ static inline int wait_for_user_access(struct davinci_mdio_data *data) return 0; reg = __raw_readl(®s->control); - if ((reg & CONTROL_IDLE) == 0) + if ((reg & CONTROL_IDLE) == 0) { + usleep_range(100, 200); continue; + } /* * An emac soft_reset may have clobbered the mdio controller's |