Re: [PATCH] phylib: Fix Freescale TBI PHY detection
From: Anton Vorontsov <hidden>
Date: 2009-01-14 15:03:34
On Tue, Jan 13, 2009 at 07:05:13PM +0300, Anton Vorontsov wrote:
Freescale on-chip TBI PHYs reports PHY ID as 0x0, but as of
commit 3ee82383f0098a2e13acc8cf1be8e47512f41e5a
Author: Giulio Benetti [off-list ref]
Date: Thu Nov 13 21:53:13 2008 +0000
phy: fix phy address bug
PHYID returns 0xffff and not 0xffffffff when not found and in some
case(at91sam9263) 0x0. Maybe this patch could be useful.
phy_device.c treats PHY ID == 0x0 as bogus IDs, and that results in
gianfar driver failure to see the TBI PHYs. This code snippet triggers:
if (!priv->tbiphy) {
printk(KERN_WARNING "SGMII mode requires that the device "
"tree specify a tbi-handle\n");
return;
}
Although tbi-handle is specified in the device tree.
Btw, technically PHY ID == 0x0 is a valid ID (if we ever see a PHY
manufactured by Xerox :-).
Signed-off-by: Anton Vorontsov <redacted>
---
There is one thing I don't actually understand though...
Andy, were you testing the TBI support on a hardware where PHY ID
!= 0x0 or maybe your TBI PHY support patch (commit b31a1d8b41513b,
dated Tue Dec 16 15:29:15 2008) was based on a bit outdated kernel
version? Because according to the git timestamps, the TBI support
was not working since the submission.
Just in case, the hardware I'm seeing the PHY ID == 0x0 is
MPC8378E-MDS.I think I got it. Probably the TBI support patch was based on the powerpc.git next, and the commit that broke the TBI support was in the net-next-2.6 tree. That explains why nobody noticed the issue.
quoted hunk ↗ jump to hunk
drivers/net/phy/phy_device.c | 9 --------- 1 files changed, 0 insertions(+), 9 deletions(-)diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index e354601..0a06e4f 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c@@ -231,15 +231,6 @@ struct phy_device * get_phy_device(struct mii_bus *bus, int addr) if ((phy_id & 0x1fffffff) == 0x1fffffff) return NULL; - /* - * Broken hardware is sometimes missing the pull-up resistor on the - * MDIO line, which results in reads to non-existent devices returning - * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent - * device as well. - */ - if (phy_id == 0) - return NULL; - dev = phy_device_create(bus, addr, phy_id); return dev;-- 1.5.6.5