2017-12-15 14:36:20

by Hemanth Puranik

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

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 <[email protected]>
---
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;
--
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

2017-12-15 15:20:27

by Timur Tabi

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

On 12/15/2017 08:35 AM, Hemanth Puranik wrote:
> 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<[email protected]>

Acked-by: Timur Tabi <[email protected]>

--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc. Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

2017-12-15 15:47:18

by Andrew Lunn

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

On Fri, Dec 15, 2017 at 08:05:58PM +0530, Hemanth Puranik wrote:
> 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 <[email protected]>

Reviewed-by: Andrew Lunn <[email protected]>

Andrew

2017-12-15 20:46:48

by David Miller

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

From: Hemanth Puranik <[email protected]>
Date: Fri, 15 Dec 2017 20:05:58 +0530

> 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 <[email protected]>

Applied, thanks.