From patchwork Tue Sep 30 00:34:46 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 394675 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id BC1AB1400B7 for ; Tue, 30 Sep 2014 10:37:46 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751165AbaI3AhV (ORCPT ); Mon, 29 Sep 2014 20:37:21 -0400 Received: from seldrel01.sonyericsson.com ([212.209.106.2]:10886 "EHLO seldrel01.sonyericsson.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754816AbaI3Aev (ORCPT ); Mon, 29 Sep 2014 20:34:51 -0400 From: Bjorn Andersson To: Kumar Gala , Andy Gross , Arnd Bergmann , Grant Likely , Ian Campbell , Mark Rutland , Pawel Moll , Rob Herring CC: , , , , Lee Jones , Liam Girdwood , Mark Brown , Samuel Ortiz Subject: [RFC 2/7] soc: qcom: Add device tree binding for SMD Date: Mon, 29 Sep 2014 17:34:46 -0700 Message-ID: <1412037291-16880-3-git-send-email-bjorn.andersson@sonymobile.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1412037291-16880-1-git-send-email-bjorn.andersson@sonymobile.com> References: <1412037291-16880-1-git-send-email-bjorn.andersson@sonymobile.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Add device tree binding documentation for the Qualcomm Shared Memory Device. Signed-off-by: Bjorn Andersson --- I was looking at having one smd node per remote processor - e.g flatten the first and second level. As all the channels, for all the remote processors are allocated from the same pool this does however not feel very natural. .../devicetree/bindings/soc/qcom/qcom,smd.txt | 82 ++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt new file mode 100644 index 0000000..c56e4fc --- /dev/null +++ b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt @@ -0,0 +1,82 @@ +Qualcomm Shared Memory Driver (SMD) binding + +This binding describes the Qualcomm Shared Memory Driver, a fifo based +communication channel for sending data between the various subsystems in +Qualcomm platforms. + +- compatible: + Usage: required + Value type: + Definition: must be "qcom,smd" + +- qcom,smem: + Usage: required + Value type: + Definition: reference to a smem node managing the shared memory items + used for smd + += EDGES + +Each subnode of the SMD node represents a remote subsystem, i.e. a remote +processor of some sort - in SMD language called an "edge". The name of the +edges are not important. + +- interrupts: + Usage: required + Value type: + Definition: should specify the IRQ used by the remote processor to + signal this processor about communication related updates + +- qcom,ipc: + Usage: required + Value type: + Definition: three entries specifying the outgoing ipc bit used for + signaling the remote processor: + - phandle to a syscon node representing the apcs registers + - u32 representing offset to the register within the syscon + - u32 representing the ipc bit within the register + +- qcom,smd-edge: + Usage: required + Value type: + Definition: an identifier representing the remote processor + += SMD DEVICES + +In turn, subnodes of the "edges" represent devices tied to SMD channels on that +"edge". The names of the devices are not important. The properties of these +nodes are defined by the individual bindings for the SMD devices - but must +contain the following property: + +- qcom,smd-channels: + Usage: required + Value type: + Definition: a list of channels tied to this device, used for matching + the device to channels + += EXAMPLE + +The following example represents a smd node, with one edge representing the +"rpm" subsystem. For the "rpm" subsystem we have a device tied to the +"rpm_request" channel. + + smd { + compatible = "qcom,smd"; + qcom,smem = <&smem>; + + rpm { + interrupts = <0 168 1>; + qcom,ipc = <&apcs 8 0>; + qcom,smd-edge = <15>; + + rpm_requests { + compatible = "qcom,rpm-msm8974"; + qcom,smd-channels = "rpm_requests"; + + #address-cells = <1>; + #size-cells = <0>; + + ... + }; + }; + };