From mboxrd@z Thu Jan 1 00:00:00 1970 From: Corentin Labbe Subject: Re: [PATCH v6 05/21] net-next: stmmac: Add dwmac-sun8i Date: Tue, 27 Jun 2017 10:21:03 +0200 Message-ID: <20170627082103.GB2468@Red> References: <20170531071852.12422-1-clabbe.montjoie@gmail.com> <20170531071852.12422-6-clabbe.montjoie@gmail.com> <8e3d73a7-e9ff-d3e2-4bce-bcc79cdf86db@arm.com> <20170627080529.GA2468@Red> Reply-To: clabbe.montjoie-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Content-Disposition: inline In-Reply-To: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Chen-Yu Tsai Cc: =?iso-8859-1?Q?Andr=E9?= Przywara , Rob Herring , Mark Rutland , Maxime Ripard , Russell King , Catalin Marinas , Will Deacon , Giuseppe Cavallaro , alexandre.torgue-qxv4g6HH51o@public.gmane.org, devicetree , netdev , linux-kernel , linux-sunxi , linux-arm-kernel , Icenowy Zheng List-Id: devicetree@vger.kernel.org On Tue, Jun 27, 2017 at 04:11:21PM +0800, Chen-Yu Tsai wrote: > On Tue, Jun 27, 2017 at 4:05 PM, Corentin Labbe > wrote: > > On Mon, Jun 26, 2017 at 01:18:23AM +0100, Andr=C3=A9 Przywara wrote: > >> On 31/05/17 08:18, Corentin Labbe wrote: > >> > The dwmac-sun8i is a heavy hacked version of stmmac hardware by > >> > allwinner. > >> > In fact the only common part is the descriptor management and the fi= rst > >> > register function. > >> > >> Hi, > >> > >> I know I am a bit late with this, but while adapting the U-Boot driver > >> to the new binding I was wondering about the internal PHY detection: > >> > >> > >> So here you seem to deduce the usage of the internal PHY by the PHY > >> interface specified in the DT (MII =3D internal, RGMII =3D external). > >> I think I raised this question before, but isn't it perfectly legal fo= r > >> a board to use MII with an external PHY even on those SoCs that featur= e > >> an internal PHY? > >> On the first glance that does not make too much sense, but apart from > >> not being the correct binding to describe all of the SoCs features I s= ee > >> two scenarios: > >> 1) A board vendor might choose to not use the internal PHY because it > >> has bugs, lacks features (configurability) or has other issues. For > >> instance I have heard reports that the internal PHY makes the SoC go > >> rather hot, possibly limiting the CPU frequency. By using an external > >> MII PHY (which are still cheaper than RGMII PHYs) this can be avoided. > >> 2) A PHY does not necessarily need to be directly connected to > >> magnetics. Indeed quite some boards use (RG)MII to connect to a switch > >> IC or some other network circuitry, for instance fibre connectors. > >> > >> So I was wondering if we would need an explicit: > >> allwinner,use-internal-phy; > >> boolean DT property to signal the usage of the internal PHY? > >> Alternatively we could go with the negative version: > >> allwinner,disable-internal-phy; > >> > >> Or what about introducing a new "allwinner,internal-mii-phy" compatibl= e > >> string for the *PHY* node and use that? > >> > >> I just want to avoid that we introduce a binding that causes us > >> headaches later. I think we can still fix this with a followup patch > >> before the driver and its binding hit a release kernel. > >> > >> Cheers, > >> Andre. > >> > > > > I just see some patch, where "phy-mode =3D internal" is valid. > > I will try to find a way to use it >=20 > Can you provide a link? https://lkml.org/lkml/2017/6/23/479 >=20 > I'm not a fan of using phy-mode for this. There's no guarantee what > mode the internal PHY uses. That's what phy-mode is for. For each soc the internal PHY mode is know and setted in emac_variant/inter= nal_phy So its not a problem. Patch comming soon --=20 You received this message because you are subscribed to the Google Groups "= linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to linux-sunxi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit https://groups.google.com/d/optout.