From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH v22 1/4] dt-bindings: soc: Add documentation for the MediaTek GCE unit Date: Mon, 2 Jul 2018 20:30:40 -0600 Message-ID: <20180703023040.GA24508@rob-hp-laptop> References: <1530098172-31385-1-git-send-email-houlong.wei@mediatek.com> <1530098172-31385-2-git-send-email-houlong.wei@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1530098172-31385-2-git-send-email-houlong.wei@mediatek.com> Sender: linux-kernel-owner@vger.kernel.org To: Houlong Wei Cc: Jassi Brar , Matthias Brugger , Daniel Kurtz , Sascha Hauer , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com, Sascha Hauer , Philipp Zabel , Nicolas Boichat , CK HU , Bibby Hsieh , YT Shen , Daoyuan Huang , Jiaguang Zhang , Dennis-YC Hsieh , Monica Wang , HS Liao , ginny.chen@m List-Id: devicetree@vger.kernel.org On Wed, Jun 27, 2018 at 07:16:09PM +0800, Houlong Wei wrote: > This adds documentation for the MediaTek Global Command Engine (GCE) unit > found in MT8173 SoCs. > > Signed-off-by: Houlong Wei > Signed-off-by: HS Liao > --- > Hi Rob, > I don't add your ACK in this version since the dt-binding description > has been changed. Thanks. > --- > .../devicetree/bindings/mailbox/mtk-gce.txt | 65 ++++++++++++++++++++ > include/dt-bindings/gce/mt8173-gce.h | 48 +++++++++++++++ > 2 files changed, 113 insertions(+) > create mode 100644 Documentation/devicetree/bindings/mailbox/mtk-gce.txt > create mode 100644 include/dt-bindings/gce/mt8173-gce.h > > diff --git a/Documentation/devicetree/bindings/mailbox/mtk-gce.txt b/Documentation/devicetree/bindings/mailbox/mtk-gce.txt > new file mode 100644 > index 0000000..26f65a4 > --- /dev/null > +++ b/Documentation/devicetree/bindings/mailbox/mtk-gce.txt > @@ -0,0 +1,65 @@ > +MediaTek GCE > +=============== > + > +The Global Command Engine (GCE) is used to help read/write registers with > +critical time limitation, such as updating display configuration during the > +vblank. The GCE can be used to implement the Command Queue (CMDQ) driver. > + > +CMDQ driver uses mailbox framework for communication. Please refer to > +mailbox.txt for generic information about mailbox device-tree bindings. > + > +Required properties: > +- compatible: Must be "mediatek,mt8173-gce" > +- reg: Address range of the GCE unit > +- interrupts: The interrupt signal from the GCE block > +- clock: Clocks according to the common clock binding > +- clock-names: Must be "gce" to stand for GCE clock > +- thread-num: Maximum threads count of GCE. mediatek,thread-num Is this needed for anything other than error checking the thread id in the mbox cells? if that's it, then drop it. > +- #mbox-cells: Should be 4. > + <&phandle channel timeout priority atomic_exec> > + phandle: Label name of a gce node. > + channel: Channel of mailbox. Be equal to the thread id of GCE. > + timeout: Maximum time of software waiting GCE processing done, in unit > + of millisecond. > + priority: Priority of GCE thread. > + atomic_exec: GCE processing continuous packets of commands in atomic > + way. > + > +Required properties for a client device: > +- mboxes: Client use mailbox to communicate with GCE, it should have this > + property and list of phandle, mailbox specifiers. > +- gce-subsys: Specify the sub-system id which is corresponding to the register > + address. What is this for? > + > +Optional properties for a client device: > +- gce-event: Specify the event if the client has any. Because the event is > + parsed by client, so client can replace 'gce-event' with other meaningful > + name. If the client sets the name, then no point having here. It must be documented in the client binding. But then, what is this for in the first place? > + > +Some vaules of properties are defined in 'dt-bindings/gce/mt8173-gce.h'. Such as > +thread number, sub-system ids, thread priority, event ids. > + > +Example: > + > + gce: gce@10212000 { mailbox@... > + compatible = "mediatek,mt8173-gce"; > + reg = <0 0x10212000 0 0x1000>; > + interrupts = ; > + clocks = <&infracfg CLK_INFRA_GCE>; > + clock-names = "gce"; > + thread-num = CMDQ_THR_MAX_COUNT; > + #mbox-cells = <4>; > + }; > + > +Example for a client device: > + > + mmsys: clock-controller@14000000 { > + compatible = "mediatek,mt8173-mmsys"; > + mboxes = <&gce 0 2000 CMDQ_THR_PRIO_LOWEST 1>, > + <&gce 1 2000 CMDQ_THR_PRIO_LOWEST 1>; > + gce-subsys = ; > + mutex-event-eof = + CMDQ_EVENT_MUTEX1_STREAM_EOF>; > + > + ... > + };