From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: Re: [PATCH] [RFC] Using hierarchy irqdomian to implement MTK intpol. Date: Thu, 25 Sep 2014 16:27:27 +0200 (CEST) Message-ID: References: <1411574696-1881-1-git-send-email-srv_yingjoe.chen@mediatek.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <1411574696-1881-1-git-send-email-srv_yingjoe.chen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Joe.C" Cc: Jiang Liu , Marc Zyngier , Mark Rutland , Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , Russell King , Jason Cooper , Benjamin Herrenschmidt , Grant Likely , "Joe.C" , Boris BREZILLON , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, srv_heupstream-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, yingjoe.chen-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, hc.yen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, eddie.huang-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, nathan.chung-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, yh.chen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, Sascha Hauer , Matthias Brugger List-Id: devicetree@vger.kernel.org On Thu, 25 Sep 2014, Joe.C wrote: > From: "Joe.C" > > Here's the first draft of using hierarchy irqdomain to implement MTK intpol > support. I have tested it and intpol works fine. Before continue, I'd like > to get your comments. This is based on Jiang's hierarchy irqdomian [1] and > my mediatek SoC basic support [2]. > > Simplified block diagram for interrupt: > > --------- --------- > ---| CIRQ |------|ARM GIC| > ---| |------| | > ---| |------| | > ---| |------| | > ---| |------| | > --------- --------- > > In device tree, interrupt-parent for other devices is cirq, child of gic. > This describe HW better and allow device to specify polarity as it is sent > by the device. I'm using interrupt-parent to specify irq domain parent in > cirq now. Maybe adding another name like 'interrupt-domain-parent' will be > better. I leave that to the DT folks. > Currently only set_type is implement in CIRQ, but I think this could extended > to cover all function gic_arch_extn provided. Right. Marc, can you have a look at this whether you can see how that might replace the rest of the arch_extn hackery? At least the avoidance of the set_type mess looks pretty reasonable. > In order to use hierarchy irq domain, gic can't use legacy irq domain anymore. > If arm,hierarchy-irq-domain property is specified, GIC will work in hierarchy > way and all interrupt must be set by device tree. > > One thing worth mention is arg in irq_domain_alloc_irqs. On x86, msi is using > struct irq_alloc_info, to pass data between irq domain. In irq_create_of_mapping(), > of_phandle_args is used. All allocs in irq_domain chain will need to use same > interrupt-cells formats. Right, but we leave that to the architecture implementation. It needs to be consistent within an architecture, so we should change the "void *arg" to a well defined type. For OF architectures this would be of_phandle_args, other architectures can define their own struct type which allows to transport data between the domains. That ensures compile time type checking. Thanks, tglx -- 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