Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754262AbbHYGql (ORCPT ); Tue, 25 Aug 2015 02:46:41 -0400 Received: from mail-oi0-f52.google.com ([209.85.218.52]:35087 "EHLO mail-oi0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750863AbbHYGqj (ORCPT ); Tue, 25 Aug 2015 02:46:39 -0400 MIME-Version: 1.0 In-Reply-To: References: <1438831173-8761-1-git-send-email-punnaia@xilinx.com> Date: Tue, 25 Aug 2015 12:16:38 +0530 X-Google-Sender-Auth: ZmwPNv4eZuuBHcgEr3ZEqK12eGw Message-ID: Subject: Re: [PATCH v4 1/2] Documentation: dt: Add Xilinx zynqmp dma device tree binding documentation From: punnaiah choudary kalluri To: Rob Herring Cc: Punnaiah Choudary Kalluri , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Michal Simek , Vinod Koul , Dan Williams , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Punnaiah Choudary , dmaengine@vger.kernel.org, "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4835 Lines: 121 Hi Rob, On Tue, Aug 25, 2015 at 12:23 AM, Rob Herring wrote: > On Wed, Aug 5, 2015 at 10:19 PM, Punnaiah Choudary Kalluri > wrote: >> Device-tree binding documentation for Xilinx zynqmp dma engine used in >> Zynq UltraScale+ MPSoC. >> >> Signed-off-by: Punnaiah Choudary Kalluri >> --- >> Changes in v4: >> - None >> Changes in v3: >> - None >> Changes in v2: >> - None >> --- >> .../devicetree/bindings/dma/xilinx/zynqmp_dma.txt | 61 ++++++++++++++++++++ >> 1 files changed, 61 insertions(+), 0 deletions(-) >> create mode 100644 Documentation/devicetree/bindings/dma/xilinx/zynqmp_dma.txt >> >> diff --git a/Documentation/devicetree/bindings/dma/xilinx/zynqmp_dma.txt b/Documentation/devicetree/bindings/dma/xilinx/zynqmp_dma.txt >> new file mode 100644 >> index 0000000..e4f92b9 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/dma/xilinx/zynqmp_dma.txt >> @@ -0,0 +1,61 @@ >> +Xilinx ZynqMP DMA engine, it does support memory to memory transfers, >> +memory to device and device to memory transfers. It also has flow >> +control and rate control support for slave/peripheral dma access. >> + >> +Required properties: >> +- compatible: Should be "xlnx,zynqmp-dma-1.0" >> +- #dma-cells: Should be <1>, a single cell holding a line request number >> +- reg: Memory map for module access >> +- interrupt-parent: Interrupt controller the interrupt is routed through >> +- interrupts: Should contain DMA channel interrupt >> +- xlnx,bus-width: AXI buswidth in bits. Should contain 128 or 64 >> + >> +Optional properties: >> +- xlnx,include-sg: Indicates the controller to operate in simple or scatter >> + gather dma mode >> +- xlnx,ratectrl: Scheduling interval in terms of clock cycles for >> + source AXI transaction >> +- xlnx,overfetch: Tells whether the channel is allowed to over fetch the data >> +- xlnx,src-issue: Number of AXI outstanding transactions on source side >> +- xlnx,desc-axi-cohrnt: Tells whether the AXI transactions generated for the >> + descriptor read are marked Non-coherent >> +- xlnx,src-axi-cohrnt: Tells whether the AXI transactions generated for the >> + source descriptor payload are marked Non-coherent >> +- xlnx,dst-axi-cohrnt: Tells whether the AXI transactions generated for the >> + dst descriptor payload are marked Non-coherent > > Do you really need 3? dma-coherent property doesn't work for you? > > Not that it should dictate the binding, but the kernel doesn't support > a device needing both coherent and non-coherent DMA ops. I will get back to you shortly on this > >> +- xlnx,desc-axi-qos: AXI QOS bits to be used for descriptor fetch >> +- xlnx,src-axi-qos: AXI QOS bits to be used for data read >> +- xlnx,dst-axi-qos: AXI QOS bits to be used for data write >> +- xlnx,desc-axi-cache: AXI cache bits to be used for descriptor fetch. >> +- xlnx,desc-axi-cache: AXI cache bits to be used for data read >> +- xlnx,desc-axi-cache: AXI cache bits to be used for data write > > These signals are generally part of the coherent or not setting. This > allows for potentially invalid combinations. > > Plus you have a copy/paste error. I will fix this. Thanks, Punnaiah > >> +- xlnx,src-burst-len: AXI length for data read. Support only power of 2 values >> + i.e 1,2,4,8 and 16 >> +- xlnx,dst-burst-len: AXI length for data write. Support only power of 2 values >> + i.e 1,2,4,8 and 16 >> + >> +Example: >> +++++++++ >> +fpd_dma_chan1: dma@FD500000 { >> + compatible = "xlnx,zynqmp-dma-1.0"; >> + reg = <0x0 0xFD500000 0x1000>; >> + #dma_cells = <1>; >> + interrupt-parent = <&gic>; >> + interrupts = <0 117 4>; >> + xlnx,bus-width = <128>; >> + xlnx,include-sg; >> + xlnx,overfetch; >> + xlnx,ratectrl = <0>; >> + xlnx,src-issue = <16>; >> + xlnx,desc-axi-cohrnt; >> + xlnx,src-axi-cohrnt; >> + xlnx,dst-axi-cohrnt; >> + xlnx,desc-axi-qos = <0>; >> + xlnx,desc-axi-cache = <0>; >> + xlnx,src-axi-qos = <0>; >> + xlnx,src-axi-cache = <2>; >> + xlnx,dst-axi-qos = <0>; >> + xlnx,dst-axi-cache = <2>; >> + xlnx,src-burst-len = <4>; >> + xlnx,dst-burst-len = <4>; >> +}; >> -- >> 1.7.4 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/