Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964873AbbLOJi6 (ORCPT ); Tue, 15 Dec 2015 04:38:58 -0500 Received: from arroyo.ext.ti.com ([192.94.94.40]:42012 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933146AbbLOJiz (ORCPT ); Tue, 15 Dec 2015 04:38:55 -0500 Subject: Re: [PATCH 2/6] ARM: DTS: da850: Use the new DT bindings for the eDMA3 To: Peter Ujfalusi References: <1449237210-16381-1-git-send-email-peter.ujfalusi@ti.com> <1449237210-16381-3-git-send-email-peter.ujfalusi@ti.com> CC: , , , From: Sekhar Nori Message-ID: <566FDF93.7050005@ti.com> Date: Tue, 15 Dec 2015 15:08:27 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <1449237210-16381-3-git-send-email-peter.ujfalusi@ti.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3357 Lines: 91 Hi Peter, On Friday 04 December 2015 07:23 PM, Peter Ujfalusi wrote: > Switch to use the ti,edma3-tpcc and ti,edma3-tptc binding for the eDMA3. > With the new bindings boards can customize and tweak the DMA channel > priority to match their needs. With the new binding the memcpy is safe > to be used since with the old binding it was not possible for a driver > to know which channel is allowed to be used as non HW triggered channel. > Using the new binding will allow us to reserve PaRAM slots to be used by > the DSP which was not possible before and prevented the da850 boards to be > moved to DT only. > > Signed-off-by: Peter Ujfalusi > --- > arch/arm/boot/dts/da850-enbw-cmc.dts | 5 +++++ > arch/arm/boot/dts/da850-evm.dts | 5 +++++ > arch/arm/boot/dts/da850.dtsi | 27 ++++++++++++++++++++++----- > 3 files changed, 32 insertions(+), 5 deletions(-) > > diff --git a/arch/arm/boot/dts/da850-enbw-cmc.dts b/arch/arm/boot/dts/da850-enbw-cmc.dts > index e750ab9086d5..ca9117624cf9 100644 > --- a/arch/arm/boot/dts/da850-enbw-cmc.dts > +++ b/arch/arm/boot/dts/da850-enbw-cmc.dts > @@ -28,3 +28,8 @@ > }; > }; > }; > + > +&edma0 { > + ti,edma-reserved-slot-ranges = /bits/ 16 <32 50>; > + ti,edma-memcpy-channels = /bits/ 16 <20 21>; > +}; > diff --git a/arch/arm/boot/dts/da850-evm.dts b/arch/arm/boot/dts/da850-evm.dts > index d807285a61cd..33467feb272a 100644 > --- a/arch/arm/boot/dts/da850-evm.dts > +++ b/arch/arm/boot/dts/da850-evm.dts > @@ -243,3 +243,8 @@ > tx-num-evt = <32>; > rx-num-evt = <32>; > }; > + > +&edma0 { > + ti,edma-reserved-slot-ranges = /bits/ 16 <32 50>; > + ti,edma-memcpy-channels = /bits/ 16 <20 21>; These correspond to PRU events. It is true that most likely they will never be used for peripheral DMA and can be dedicated as memcpy channels. However, since this is being encoded in DT, we need to be sure that they will never be used for peripheral DMA on this board. So, I would prefer if you do not reserve any channels for memcpy until there is a real need/usecase for them. I know the board file has these reserved but board file could be updated as you liked. With DT we need to maintain backward compatibility. So I would rather do it when there is an actual need for it. In future, if/when we gain QDMA support, the QDMA channels could be used for memcopy. > +}; > diff --git a/arch/arm/boot/dts/da850.dtsi b/arch/arm/boot/dts/da850.dtsi > index e73f5efb3aa3..9e46eb51a8da 100644 > --- a/arch/arm/boot/dts/da850.dtsi > +++ b/arch/arm/boot/dts/da850.dtsi > @@ -151,11 +151,28 @@ > > }; > edma0: edma@01c00000 { > - compatible = "ti,edma3"; > + compatible = "ti,edma3-tpcc"; > /* eDMA3 CC0: 0x01c0 0000 - 0x01c0 7fff */ > reg = <0x0 0x8000>; > - interrupts = <11 13 12>; > - #dma-cells = <1>; > + reg-names = "edma3_cc"; > + interrupts = <11 12>; > + interrupt-names = "edma3_ccint", "edma3_ccerrint"; > + #dma-cells = <2>; > + > + ti,tptcs = <&edma0_tptc0 7>, <&edma0_tptc1 0>; > + ti,edma-memcpy-channels = /bits/ 16 <20 21>; Same here. I would drop this. Thanks, Sekhar -- 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/