> -----Original Message-----
> From: Antoine Tenart <antoine.ten...@bootlin.com>
> Sent: Monday, February 18, 2019 12:52 PM
> To: Russell King - ARM Linux admin <li...@armlinux.org.uk>
> Cc: Antoine Tenart <antoine.ten...@bootlin.com>; da...@davemloft.net;
> net...@vger.kernel.org; linux-kernel@vger.kernel.org;
> thomas.petazz...@bootlin.com; maxime.chevall...@bootlin.com;
> gregory.clem...@bootlin.com; miquel.ray...@bootlin.com; Nadav Haklai
> <nad...@marvell.com>; Stefan Chulski <stef...@marvell.com>; Yan
> Markman <ymark...@marvell.com>; m...@semihalf.com
> Subject: [EXT] Re: [PATCH net-next 10/13] net: mvpp2: reset the XPCS while
> reconfiguring the serdes lanes
>
> External Email
>
> ----------------------------------------------------------------------
> Russell,
>
> On Mon, Feb 18, 2019 at 10:47:57AM +0000, Russell King - ARM Linux admin
> wrote:
> >
> > Another case that needs to be considered: if the XPCS should be placed
> > into reset while reconfiguring the serdes lanes, is the same treatment
> > needed for the GMAC?
>
> That's something I wanted to check as well. I don't know for the GMAC, while
> I'm sure the documentation explicitly state to put the XPCS in reset when
> reconfiguring the lanes.
HW recommendation upon Serdes reconfiguration are the following:
1. Disable port(CTRL0_REG - in XLG/GMAC)
2. Put port in reset (both XLG/GMAC)
3. For KR - put in reset MPCS (MAC control clock, RX SD clock, TX SD clock),
XPSC is RXAUI/XAUI clock domain
4. Power down Serdes lane
Do reconfiguration of Serdes.
5. Enable Serdes lane
6. Disable MPCS reset for KR
7. Disable port reset (both XLG/GMAC)
8. Enable port (both XLG/GMAC)
Stefan,
Best Regards.
