Hi Daniel, > -----Original Message----- > From: Daniel Walker [mailto:danie...@cisco.com] > Sent: Tuesday, April 18, 2017 8:26 PM > To: Harini Katakam <hari...@xilinx.com>; Andrew Lunn <and...@lunn.ch> > Cc: Florian Fainelli <f.faine...@gmail.com>; Andy Fleming > <aflem...@freescale.com>; netdev@vger.kernel.org; HEMANT RAMDASI > <hramd...@cisco.com>; Julius Hemanth Pitti -X (jpitti - MONTA VISTA > SOFTWARE INC at Cisco) <jpi...@cisco.com>; harinikatakamli...@gmail.com > Subject: Re: Marvell phy errata origins? > > On 04/18/2017 07:41 AM, Harini Katakam wrote: > > Hi Daniel, > > > >> -----Original Message----- > >> From: Daniel Walker [mailto:danie...@cisco.com] > >> Sent: Tuesday, April 18, 2017 8:05 PM > >> To: Harini Katakam <hari...@xilinx.com>; Andrew Lunn <and...@lunn.ch> > >> Cc: Florian Fainelli <f.faine...@gmail.com>; Andy Fleming > >> <aflem...@freescale.com>; netdev@vger.kernel.org; HEMANT RAMDASI > >> <hramd...@cisco.com>; Julius Hemanth Pitti -X (jpitti - MONTA VISTA > >> SOFTWARE INC at Cisco) <jpi...@cisco.com> > >> Subject: Re: Marvell phy errata origins? > >> > >> On 04/18/2017 07:31 AM, Harini Katakam wrote: > >>> Hi Daniel, > >>> > >>>> -----Original Message----- > >>>> From: Daniel Walker [mailto:danie...@cisco.com] > >>>> Sent: Tuesday, April 18, 2017 7:48 PM > >>>> To: Andrew Lunn <and...@lunn.ch> > >>>> Cc: Florian Fainelli <f.faine...@gmail.com>; Andy Fleming > >>>> <aflem...@freescale.com>; Harini Katakam <hari...@xilinx.com>; > >>>> netdev@vger.kernel.org; HEMANT RAMDASI <hramd...@cisco.com>; > Julius > >>>> Hemanth Pitti -X (jpitti - MONTA VISTA SOFTWARE INC at Cisco) > >>>> <jpi...@cisco.com> > >>>> Subject: Re: Marvell phy errata origins? > >>>> > >>>> On 04/18/2017 07:04 AM, Andrew Lunn wrote: > >>>>> On Tue, Apr 18, 2017 at 06:16:33AM -0700, Daniel Walker wrote: > >>> <snip> > >>>>>> In Harini's commit > >>>>>> message for , > >>>>>> > >>>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gi > >>>>>> t/ co mmit/drivers/net/phy/marvell.c?id=3ec0a0f10ceb > >>>>>> > >>>>>> "This function has a sequence accessing Page 5 and Register 31, > >>>>>> both of which are not defined or reserved for this PHY" > >>>>>> > >>>>>> For the 88E1112 we see that these are "Factory Test Modes" which > >>>>>> the contents of are not documented. They aren't really "not > >>>>>> defied", and aren't really "reserved" .. Marvell support claims > >>>>>> they don't support these drivers, and Freescale seems to be > >>>>>> adding these drivers, and the line we are looking at. > >>>>>> > >>>>>> We had some issues with our PHY which were corrected with the > >>>>>> same patch Harini used but modified for the M88E1112. We're > >>>>>> trying to get to the bottom of where this code came from and what > >>>>>> it was suppose to be doing. > >>>>> I tried to find this errata fix in the Marvell reference code. And > >>>>> failed to find it. But it is "Vendor Crap" code, hard to find > >>>>> anything in it. > >>>>> > >>>>> My guess is, this errata just applies to one model of PHY, maybe > >>>>> even one revision of one model of a PHY. The hard bit is figuring > >>>>> out what actually needs it. Do you have access to Marvell datasheets? > >>> I have access to the datasheets for 88E1111, 88E1112 and 88E1116 > >>> (and another family 151x) - None of them have these register details > >>> or the errata > >> documented. > >> > >> http://www.dexsilicium.com/Marvell_88E1112.pd > >> > >> > >> Is this the same datasheet ? In this one on page 81 there is page 5 > >> register 31 is "Factory Test Modes" , do you not have that? > > Yes, it is the same datasheet. That is what I meant - it just says > > factory test modes But there is no register description. > > I would call that undocumented. I suspect there are things inside the "Factory > Test Modes" which could be helpful to fix errata. Things which Marvell might > not > want to document universally.
OK, agreed. > > Can you describe what sort of issue you found which was the motivation for > your patch ? Or did you remove the code because you did not know what it was > used for? > I added this patch for 88E1111 because that datasheet does not even have Page 5 Reg 31 as "Factory Test mode" - it is reserved space. Any access to that register failed. Since this register was clearly not part of 88E1111 PHY and irrelevant, I removed that code. Regards, Harini
