linux-kernel - Re: [PATCH v3 1/6] phy: add a driver for the Berlin SATA PHY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5701370.bQb4QoHk6c@wuerfel>
Date:	Wed, 14 May 2014 21:10:09 +0200
From:	Arnd Bergmann <arnd@...db.de>
To:	Sebastian Hesselbarth <sebastian.hesselbarth@...il.com>
Cc:	linux-arm-kernel@...ts.infradead.org,
	thomas.petazzoni@...e-electrons.com, zmxu@...vell.com,
	devicetree@...r.kernel.org,
	Antoine Ténart 
	<antoine.tenart@...e-electrons.com>, linux-kernel@...r.kernel.org,
	kishon@...com, linux-ide@...r.kernel.org,
	alexandre.belloni@...e-electrons.com, jszhang@...vell.com,
	tj@...nel.org
Subject: Re: [PATCH v3 1/6] phy: add a driver for the Berlin SATA PHY

On Wednesday 14 May 2014 20:56:29 Sebastian Hesselbarth wrote:
> On 05/14/2014 08:51 PM, Arnd Bergmann wrote:
> > On Wednesday 14 May 2014 20:42:16 Sebastian Hesselbarth wrote:
> >>>> For the driver, Antoine then would have to squeeze all PHY register
> >>>> mangling in phy-berlin2.c and see how to make ahci-platform aware of
> >>>> individual port nodes (I haven't looked up if it already exists, sorry)
> >>>> and announce only enabled port child nodes, right?
> >>>
> >>> I've been thinking some more about this aspect. I don't actually have
> >>> a strong opinion on whether it's better to use the generic ahci-platform
> >>> driver, or to keep the multi-phy support as a special variant for
> >>> berlin. If we do the latter, it would however be good to define the
> >>> binding in a way that lets us later merge things into the generic phy
> >>> driver in case we get more of the same.
> >>
> >> Hmm, IMHO multi-phy support is orthogonal to ahci-platform, isn't it?
> >> ahci-platform needs to know about the phy property and calls some
> >> helper that deals with the phy-specifier?
> >>
> >> About a generic _phy_ driver, I am not so sure if berlin is the best
> >> template right now 
> >>
> >> So, my call would be:
> >> - make ahci-platform aware of port sub-nodes and phy properties
> >> - have a berlin specific PHY driver
> > 
> > I'm not sure if we need sub-nodes per port, it should be enough
> > to have an array of phys, plus a way to match them up with the
> > ports.
> 
> Actually, I'd love to see sub-nodes per port as it will allow to
> disabled unused ports on a per-board basis.
> 
> I have this in mind for a long time for Kirkwood's SATA node already:
> Consider a board where you have the one available SATA plug connected
> to port 1. How would that work out with status = "disabled"/"okay" that
> doesn't allow array of strings obviously?

A simple bit mask would work fine, but I see your point. Doing
status="disabled" per port sounds nice.

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/