Subject: Re: Atheros 8035 PHY only works when at803x_config_init() is commented out

From: Daniel Mack <[email-masked]>
Date: Thu, 09 Apr 2015 17:32:59 +0200

On 04/09/2015 05:22 PM, Mason wrote:
> For the record, I dumped the PHY registers
> A) upon entering phy_init_hw
> B) before leaving phy_init_hw (thus right after at803x_config_init)
> 
> IDX 1: b2 LINK STATUS, b5 AUTO-NEGOTIATION COMPLETE
> => Difference in status bits, seems reasonable
> 
> IDX 5: Link partner ability (base page)
> => seems reasonable (no partner yet?)
> 
> IDX 6: Auto-Negotiation Expansion
> => seems reasonable (no partner yet?)
> 
> IDX 10: 1000 BASE-T Status (HW reset = SW reset = 0)
> (ALSO: Contents of this register clear after a read operation has occurred.)
> => Looks like my own read cleared it
> 
> IDX 17: PHY-Specific Status
> b1 = "POLARITY (real time)"?
> => Difference in status bits, seems reasonable? (
> 
> IDX 19: Interrupt Status
> => Looks like some interrupt requests might have been discarded?
> 
> IDX 27: This register is undocumented
> 
> Nothing looks suspicious, except maybe the Interrupt Status?

What about the debug registers, such as the one that configures the
RGMII TX/RX clock delay (4.2.25, 4.2.26). These are indirectly
addressed, see at803x_config_init().

Daniel