From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Subject: Re: [PATCH RFT 0/8] Marvell PXA168 libphy handling and Berlin Ethernet Date: Thu, 9 Oct 2014 16:47:04 +0200 Message-ID: <20141009164704.7286fc3f@free-electrons.com> References: <1412858346-11334-1-git-send-email-sebastian.hesselbarth@gmail.com> <20141009163315.2a9e1806@free-electrons.com> <54369EAC.5040301@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Florian Fainelli , Eric Miao , netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Antoine =?UTF-8?B?VMOpbmFydA==?= , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Haojian Zhuang , "David S. Miller" , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Sebastian Hesselbarth Return-path: In-Reply-To: <54369EAC.5040301-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org Dear Sebastian Hesselbarth, On Thu, 09 Oct 2014 16:41:48 +0200, Sebastian Hesselbarth wrote: > > Hum, in mvneta, we already disabled the automatic negotiation and use > > libphy. What makes you think the current mvneta driver is wrong in this > > respect? > > I didn't check mvneta, but remember Ezequiel didn't clear all AN bits > in the barebox driver (which is based on Linux mvneta). Just mentioned > that I'll have a closer look at it. Ah, ok. > But I agree, regarding libphy support mvneta is probably the best > already. Well, I initially remember that the original driver coming from Marvell was using the HW PHY stuff, and that I changed that because it would not integrate well with the kernel libphy. A drawback of this is that because the hardware has built-in PHY polling which triggers a MAC interrupt when the PHY status changes, they typically don't wire up the PHY interrupt. Therefore, since we're not able to use the MAC interrupt for PHY event notifications, we rely on software PHY polling, which means that link up / link down events take a few seconds to be noticed by the kernel. Unfortunately, I don't think the hardware allows to use the hardware PHY polling to get link changes interrupt, but not let the hardware configure the PHY itself. Best regards, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html