From patchwork Fri Jan 29 22:35:05 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 575864 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 551E6140BED for ; Sat, 30 Jan 2016 09:41:32 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755485AbcA2Wfd (ORCPT ); Fri, 29 Jan 2016 17:35:33 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:57456 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755476AbcA2Wfb (ORCPT ); Fri, 29 Jan 2016 17:35:31 -0500 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id BAEB3604DF; Fri, 29 Jan 2016 22:35:30 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1000) id ACDD9604BA; Fri, 29 Jan 2016 22:35:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 2CF1C6044B; Fri, 29 Jan 2016 22:35:28 +0000 (UTC) From: Sinan Kaya To: dmaengine@vger.kernel.org, marc.zyngier@arm.com, mark.rutland@arm.com, timur@codeaurora.org, devicetree@vger.kernel.org, cov@codeaurora.org, vinod.koul@intel.com, jcm@redhat.com Cc: shankerd@codeaurora.org, vikrams@codeaurora.org, eric.auger@linaro.org, agross@codeaurora.org, arnd@arndb.de, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya , linux-kernel@vger.kernel.org Subject: [PATCH V13 02/10] dma: hidma: Add Device Tree binding Date: Fri, 29 Jan 2016 17:35:05 -0500 Message-Id: <1454106914-15857-3-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1454106914-15857-1-git-send-email-okaya@codeaurora.org> References: <1454106914-15857-1-git-send-email-okaya@codeaurora.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Add documentation for the Qualcomm Technologies HIDMA binding. Signed-off-by: Sinan Kaya Acked-by: Rob Herring --- .../devicetree/bindings/dma/qcom_hidma_mgmt.txt | 92 ++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt diff --git a/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt b/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt new file mode 100644 index 0000000..e3677a5 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt @@ -0,0 +1,92 @@ +Qualcomm Technologies HIDMA Management interface + +Qualcomm Technologies HIDMA is a high speed DMA device. It only supports +memcpy and memset capabilities. It has been designed for virtualized +environments. + +Each HIDMA HW instance consists of multiple DMA channels. These channels +share the same bandwidth. The bandwidth utilization can be parititioned +among channels based on the priority and weight assignments. + +There are only two priority levels and 15 weigh assignments possible. + +Other parameters here determine how much of the system bus this HIDMA +instance can use like maximum read/write request and and number of bytes to +read/write in a single burst. + +Main node required properties: +- compatible: "qcom,hidma-mgmt-1.0"; +- reg: Address range for DMA device +- dma-channels: Number of channels supported by this DMA controller. +- max-write-burst-bytes: Maximum write burst in bytes that HIDMA can + occupy the bus for in a single transaction. A memcpy requested is + fragmented to multiples of this amount. This parameter is used while + writing into destination memory. Setting this value incorrectly can + starve other peripherals in the system. +- max-read-burst-bytes: Maximum read burst in bytes that HIDMA can + occupy the bus for in a single transaction. A memcpy request is + fragmented to multiples of this amount. This parameter is used while + reading the source memory. Setting this value incorrectly can starve + other peripherals in the system. +- max-write-transactions: This value is how many times a write burst is + applied back to back while writing to the destination before yielding + the bus. +- max-read-transactions: This value is how many times a read burst is + applied back to back while reading the source before yielding the bus. +- channel-reset-timeout-cycles: Channel reset timeout in cycles for this SOC. + Once a reset is applied to the HW, HW starts a timer for reset operation + to confirm. If reset is not completed within this time, HW reports reset + failure. + +Sub-nodes: + +HIDMA has one or more DMA channels that are used to move data from one +memory location to another. + +When the OS is not in control of the management interface (i.e. it's a guest), +the channel nodes appear on their own, not under a management node. + +Required properties: +- compatible: must contain "qcom,hidma-1.0" +- reg: Addresses for the transfer and event channel +- interrupts: Should contain the event interrupt +- desc-count: Number of asynchronous requests this channel can handle +- channel-index: The HW event channel completions will be delivered. +- iommus: required a iommu node + +Example: + +Hypervisor OS configuration: + + hidma-mgmt@f9984000 = { + compatible = "qcom,hidma-mgmt-1.0"; + reg = <0xf9984000 0x15000>; + dma-channels = <6>; + max-write-burst-bytes = <1024>; + max-read-burst-bytes = <1024>; + max-write-transactions = <31>; + max-read-transactions = <31>; + channel-reset-timeout-cycles = <0x500>; + + hidma_24: dma-controller@0x5c050000 { + compatible = "qcom,hidma-1.0"; + reg = <0 0x5c050000 0x0 0x1000>, + <0 0x5c0b0000 0x0 0x1000>; + interrupts = <0 389 0>; + desc-count = <10>; + iommus = <&system_mmu>; + channel-index = <4>; + }; + }; + +Guest OS configuration: + + hidma_24: dma-controller@0x5c050000 { + compatible = "qcom,hidma-1.0"; + reg = <0 0x5c050000 0x0 0x1000>, + <0 0x5c0b0000 0x0 0x1000>; + interrupts = <0 389 0>; + desc-count = <10>; + channel-index = <4>; + iommus = <&system_mmu>; + };