From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Daney Subject: Re: [PATCH 1/3] Docs: dt: add generic MSI bindings Date: Thu, 23 Jul 2015 11:26:11 -0700 Message-ID: <55B131C3.8050009@caviumnetworks.com> References: <1437670365-20704-1-git-send-email-mark.rutland@arm.com> <1437670365-20704-2-git-send-email-mark.rutland@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1437670365-20704-2-git-send-email-mark.rutland-5wv7dgnIgG8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Rutland , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, marc.zyngier-5wv7dgnIgG8@public.gmane.org, robin.murphy-5wv7dgnIgG8@public.gmane.org, lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org, arnd-r2nGTMty4D4@public.gmane.org, treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, majun258-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, thunder.leizhen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, tirumalesh.chalamarla-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org, laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org List-Id: devicetree@vger.kernel.org On 07/23/2015 09:52 AM, Mark Rutland wrote: [...] > +MSI clients > +=========== > + > +MSI clients are devices which generate MSIs. For each MSI they wish to > +generate, the doorbell and payload may be configured, though sideband > +information may not be configurable. > + > +Required properties: > +-------------------- > + > +- msi-parent: A list of phandle + msi-specifier pairs, one for each MSI > + controller which the device is capable of using. > + We say here that "msi-parent" consists of pairs ... > + This property is unordered, and MSIs may be allocated from any combination of > + MSI controllers listed in the msi-parent property. > + > + If a device has restrictions on the allocation of MSIs, these restrictions > + must be described with additional properties. > + > + When #msi-cells is non-zero, busses with an msi-parent will require > + additional properties to describe the relationship between devices on the bus > + and the set of MSIs they can potentially generate. > + > + > +Example > +======= > + > +/ { > + #address-cells = <1>; > + #size-cells = <1>; > + > + msi_a: msi-controller@a { > + reg = <0xa 0xf00>; > + compatible = "vendor-a,some-controller"; > + msi-controller; > + /* No sideband data, so #msi-cells omitted */ > + }; > + > + msi_b: msi-controller@b { > + reg = <0xb 0xf00>; > + compatible = "vendor-b,another-controller"; > + msi-controller; > + /* Each device has some unique ID */ > + #msi-cells = <1>; > + }; > + > + msi_c: msi-controller@c { > + reg = <0xb 0xf00>; > + compatible = "vendor-b,another-controller"; > + msi-controller; > + /* Each device has some unique ID */ > + #msi-cells = <1>; > + }; > + > + dev@0 { > + reg = <0x0 0xf00>; > + compatible = "vendor-c,some-device"; > + > + /* Can only generate MSIs to msi_a */ > + msi-parent = <&msi_a>; My device-tree syntax foo is a little rusty, but doesn't "msi-parent" need a pair of elements? This has only the phandle. > + }; > + > + dev@1 { > + reg = <0x1 0xf00>; > + compatible = "vendor-c,some-device"; > + > + /* > + * Can generate MSIs to either A or B. > + */ > + msi-parent = <&msi_a>, <&msi_b 0x17>; ... same here, ... > + }; > + > + dev@2 { > + reg = <0x2 0xf00>; > + compatible = "vendor-c,some-device"; > + /* > + * Has different IDs at each MSI controller. > + * Can generate MSIs to all of the MSI controllers. > + */ > + msi-parent = <&msi_a>, <&msi_b 0x17>, <&msi_c 0x53>; ... and here > + }; > +}; > -- 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