diff mbox

[U-Boot,v2,1/7] net: phy: ensure Gigabit features are masked off if requested

Message ID 1452693577-25786-2-git-send-email-abrodkin@synopsys.com
State Accepted
Commit bbdcaff
Delegated to: Joe Hershberger
Headers show

Commit Message

Alexey Brodkin Jan. 13, 2016, 1:59 p.m. UTC 
From: Florian Fainelli <f.fainelli@gmail.com>

When a Gigabit PHY device is connected to a 10/100Mbits capable Ethernet
MAC, the driver will restrict the phydev->supported modes to mask off
Gigabit. If the Gigabit PHY comes out of reset with the Gigabit features
set by default in MII_CTRL1000, it will keep advertising these feature,
so by the time we call genphy_config_advert(), the condition on
phydev->supported having the Gigabit features on is false, and we do not
update MII_CTRL1000 with updated values, and we keep advertising Gigabit
features, eventually configuring the PHY for Gigabit whilst the Ethernet
MAC does not support that.

This patches fixes the problem by ensuring that the Gigabit feature bits
are always cleared in MII_CTRL1000, if the PHY happens to be a Gigabit
PHY, and then, if Gigabit features are supported, setting those and
updating MII_CTRL1000 accordingly.

This is a copy of patch from Linux kernel, see
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5273e3a5ca94fbeb8e07d31203069220d5e682aa

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
---

Changes v1 -> v2:
 No changes, this is just a resent in series with other related patches.

 drivers/net/phy/phy.c | 43 ++++++++++++++++++++++++++-----------------
 1 file changed, 26 insertions(+), 17 deletions(-)

Comments

Joe Hershberger Jan. 27, 2016, 4:03 p.m. UTC | #1 
On Wed, Jan 13, 2016 at 7:59 AM, Alexey Brodkin
<Alexey.Brodkin@synopsys.com> wrote:
> From: Florian Fainelli <f.fainelli@gmail.com>
>
> When a Gigabit PHY device is connected to a 10/100Mbits capable Ethernet
> MAC, the driver will restrict the phydev->supported modes to mask off
> Gigabit. If the Gigabit PHY comes out of reset with the Gigabit features
> set by default in MII_CTRL1000, it will keep advertising these feature,
> so by the time we call genphy_config_advert(), the condition on
> phydev->supported having the Gigabit features on is false, and we do not
> update MII_CTRL1000 with updated values, and we keep advertising Gigabit
> features, eventually configuring the PHY for Gigabit whilst the Ethernet
> MAC does not support that.
>
> This patches fixes the problem by ensuring that the Gigabit feature bits
> are always cleared in MII_CTRL1000, if the PHY happens to be a Gigabit
> PHY, and then, if Gigabit features are supported, setting those and
> updating MII_CTRL1000 accordingly.
>
> This is a copy of patch from Linux kernel, see
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5273e3a5ca94fbeb8e07d31203069220d5e682aa
>
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
> Cc: Joe Hershberger <joe.hershberger@ni.com>
> ---

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Joe Hershberger Jan. 29, 2016, 9:27 p.m. UTC | #2 
Hi Alexey,

https://patchwork.ozlabs.org/patch/566944/ was applied to u-boot-net.git.

Thanks!
-Joe
diff mbox

Patch

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 51b5746..084276f 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -38,11 +38,10 @@  DECLARE_GLOBAL_DATA_PTR;
 static int genphy_config_advert(struct phy_device *phydev)
 {
 	u32 advertise;
-	int oldadv, adv;
+	int oldadv, adv, bmsr;
 	int err, changed = 0;
 
-	/* Only allow advertising what
-	 * this PHY supports */
+	/* Only allow advertising what this PHY supports */
 	phydev->advertising &= phydev->supported;
 	advertise = phydev->advertising;
 
@@ -79,29 +78,39 @@  static int genphy_config_advert(struct phy_device *phydev)
 		changed = 1;
 	}
 
+	bmsr = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);
+	if (bmsr < 0)
+		return bmsr;
+
+	/* Per 802.3-2008, Section 22.2.4.2.16 Extended status all
+	 * 1000Mbits/sec capable PHYs shall have the BMSR_ESTATEN bit set to a
+	 * logical 1.
+	 */
+	if (!(bmsr & BMSR_ESTATEN))
+		return changed;
+
 	/* Configure gigabit if it's supported */
-	if (phydev->supported & (SUPPORTED_1000baseT_Half |
-				SUPPORTED_1000baseT_Full)) {
-		oldadv = adv = phy_read(phydev, MDIO_DEVAD_NONE, MII_CTRL1000);
+	oldadv = adv = phy_read(phydev, MDIO_DEVAD_NONE, MII_CTRL1000);
+
+	if (adv < 0)
+		return adv;
 
-		if (adv < 0)
-			return adv;
+	adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
 
-		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
+	if (phydev->supported & (SUPPORTED_1000baseT_Half |
+				SUPPORTED_1000baseT_Full)) {
 		if (advertise & SUPPORTED_1000baseT_Half)
 			adv |= ADVERTISE_1000HALF;
 		if (advertise & SUPPORTED_1000baseT_Full)
 			adv |= ADVERTISE_1000FULL;
+	}
 
-		if (adv != oldadv) {
-			err = phy_write(phydev, MDIO_DEVAD_NONE, MII_CTRL1000,
-					adv);
+	if (adv != oldadv)
+		changed = 1;
 
-			if (err < 0)
-				return err;
-			changed = 1;
-		}
-	}
+	err = phy_write(phydev, MDIO_DEVAD_NONE, MII_CTRL1000, adv);
+	if (err < 0)
+		return err;
 
 	return changed;
 }