From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhou Wang Subject: Re: [PATCH v10 4/6] PCI: hisi: Add PCIe host support for HiSilicon SoC Hip05 Date: Wed, 14 Oct 2015 17:44:11 +0800 Message-ID: <561E23EB.7050504@hisilicon.com> References: <1444445957-239522-1-git-send-email-wangzhou1@hisilicon.com> <11677087.JbqAo0FWJE@wuerfel> <561E1957.5030503@hisilicon.com> <30775300.COZ4nEMWXC@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <30775300.COZ4nEMWXC@wuerfel> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann Cc: Gabriele Paoloni , Bjorn Helgaas , Bjorn Helgaas , "jingoohan1-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "pratyush.anand-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org" , "thomas.petazzoni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org" , "lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org" , "james.morse-5wv7dgnIgG8@public.gmane.org" , "Liviu.Dudau-5wv7dgnIgG8@public.gmane.org" , "jason-NLaQJdtUoK4Be96aLqz0jA@public.gmane.org" , "robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "gabriel.fernandez-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , "Minghuan.Lian-KZfg59tc24xl57MIdRCFDg@public.gmane.org" , "linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: devicetree@vger.kernel.org On 2015/10/14 17:06, Arnd Bergmann wrote: > On Wednesday 14 October 2015 16:59:03 Zhou Wang wrote: >> >> Hi Arnd, >> >> In Hip05 PCIe host, it uses GITS_TRANSLATER's address to get TLP package >> which contains MSI address and MSI data, and then combine BDF and MSI data >> to a 32 bit data which will be writen to GITS_TRANSLATER register of ITS. >> >> I think maybe this is a defect of our PCIe controller. > > I'd consider it a bug in the firmware if this is not set up correctly > before boot. > >>> I don't think what you do here is safe because the 'reg' property >>> of the MSI controller might point to the address that is used for >>> the message directly. >> >> I see your point, however we must get address of GITS_TRANSLATER and >> set it to PCIe host. How about adding necessary comments here? > > This seems to just be static setup that should be done before Linux > is even loaded. Any reason you can't do it that way? > There are some ITSs in Hip05-D02 platform, in fact, we can use any of them as a msi-controller, which we can configure in dts. I am afraid that hard-setting the value in BIOS would lead to restrictions in terms of flexibility, as with the current implementation the same BIOS-driver can fit different DTS structures. Regards, Zhou > Arnd > > . > -- 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