netdev - Re: [PATCH 12/12] ptp: Added a clock driver for the National Semiconductor PHYTER.

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]

Date:	Wed, 16 Jun 2010 09:10:42 -0600
From:	Grant Likely <grant.likely@...retlab.ca>
To:	Richard Cochran <richardcochran@...il.com>
Cc:	netdev@...r.kernel.org, devicetree-discuss@...ts.ozlabs.org,
	linuxppc-dev@...ts.ozlabs.org,
	linux-arm-kernel@...ts.infradead.org,
	Krzysztof Halasa <khc@...waw.pl>
Subject: Re: [PATCH 12/12] ptp: Added a clock driver for the National 
	Semiconductor PHYTER.

On Wed, Jun 16, 2010 at 4:05 AM, Richard Cochran
<richardcochran@...il.com> wrote:
> On Tue, Jun 15, 2010 at 12:49:13PM -0600, Grant Likely wrote:
>> Won't this break things for existing DP83640 users?
>
> Nope, the driver was only added five patches ago, and it only offers
> the timestamping stuff. The standard PHY functions just call the
> generic functions, so the PHY works fine even without this driver.
>
>> > +static struct ptp_clock *dp83640_clock;
>> > +DEFINE_SPINLOCK(clock_lock); /* protects the one and only dp83640_clock */
>>
>> Why only one?  Is it not possible to have 2 of these PHYs in a system?
>
> Yes, you can have multiple PHYs, but only one PTP clock.
>
> If you do use multiple PHYs, then you must wire their clocks together
> and adjust the PTP clock on only one of the PHYs.
>
>
> Thanks for your other comments,

You're welcome.  Make sure to cc: linux-kernel on your next posting.
I commented on what I could, but there is a lot of code outside my
areas of expertise.  In particular the time keeping code needs to be
looked at by the maintainers in that area.

Cheers,
g.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html