[PATCH] net: qcom/emac: Reduce timeout for mdio read/write

From: Hemanth Puranik
Date: Fri Dec 15 2017 - 09:36:23 EST


Currently mdio read/write takes around ~115us as the timeout
between status check is set to 100us.
By reducing the timeout to 1us mdio read/write takes ~15us to
complete. This improves the link up event response.

Signed-off-by: Hemanth Puranik <hpuranik@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/qualcomm/emac/emac-phy.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-phy.c b/drivers/net/ethernet/qualcomm/emac/emac-phy.c
index 18461fc..53dbf1e 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-phy.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-phy.c
@@ -47,6 +47,7 @@
#define MDIO_CLK_25_28 7

#define MDIO_WAIT_TIMES 1000
+#define MDIO_STATUS_DELAY_TIME 1

static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum)
{
@@ -65,7 +66,7 @@ static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum)

if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
!(reg & (MDIO_START | MDIO_BUSY)),
- 100, MDIO_WAIT_TIMES * 100))
+ MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100))
return -EIO;

return (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK;
@@ -88,8 +89,8 @@ static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
writel(reg, adpt->base + EMAC_MDIO_CTRL);

if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
- !(reg & (MDIO_START | MDIO_BUSY)), 100,
- MDIO_WAIT_TIMES * 100))
+ !(reg & (MDIO_START | MDIO_BUSY)),
+ MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100))
return -EIO;

return 0;
--
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