From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56BFCC3279B for ; Tue, 10 Jul 2018 15:45:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 04747208F7 for ; Tue, 10 Jul 2018 15:45:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="DqSrVO4z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 04747208F7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=crapouillou.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934256AbeGJPpL (ORCPT ); Tue, 10 Jul 2018 11:45:11 -0400 Received: from outils.crapouillou.net ([89.234.176.41]:39258 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933501AbeGJPpJ (ORCPT ); Tue, 10 Jul 2018 11:45:09 -0400 Date: Tue, 10 Jul 2018 17:45:02 +0200 From: Paul Cercueil Subject: Re: [PATCH 06/14] dmaengine: dma-jz4780: Add support for the JZ4725B SoC To: Vinod Cc: Rob Herring , Mark Rutland , Ralf Baechle , Paul Burton , James Hogan , Zubair Lutfullah Kakakhel , Mathieu Malaterre , Daniel Silsby , dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org Message-Id: <1531237502.17118.3@crapouillou.net> In-Reply-To: <20180709171458.GL22377@vkoul-mobl> References: <20180703123214.23090-1-paul@crapouillou.net> <20180703123214.23090-7-paul@crapouillou.net> <20180709171458.GL22377@vkoul-mobl> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1531237507; bh=WjTJmSBBrurN9JyF9IyWDMyPaD+mqwPGq8mYopQDoG8=; h=Date:From:Subject:To:Cc:Message-Id:In-Reply-To:References:MIME-Version:Content-Type:Content-Transfer-Encoding; b=DqSrVO4z5BhlGLAOU7Z7L7XLCxV2kHd9ITCUDKWOvlkRE+7O0nP2/683PCeGYv3cWc3IJg75AogCbLYK/lEnrvC2CDpXNh/7qnaTqTTlxitVmskMLN6u8CHblLLIT36BaR2eRDLMn7z9CBmhWFHhg82K+V0WC6boUZNfTN4v+K0= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le lun. 9 juil. 2018 =E0 19:14, Vinod a =E9crit : > On 03-07-18, 14:32, Paul Cercueil wrote: >> The JZ4725B has one DMA core starring six DMA channels. >> As for the JZ4770, each DMA channel's clock can be enabled with >> a register write, the difference here being that once started, it >> is not possible to turn it off. >=20 > ok so disable for this, right.. >=20 >> @@ -204,6 +205,8 @@ static inline void=20 >> jz4780_dma_chan_enable(struct jz4780_dma_dev *jzdma, >> { >> if (jzdma->version =3D=3D ID_JZ4770) >> jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DCKES, BIT(chn)); >> + else if (jzdma->version =3D=3D ID_JZ4725B) >> + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DCKE, BIT(chn)); >=20 > but you are writing to a different register here.. Yes. SoCs >=3D JZ4770 have the DCKE read-only register, and DCKES/DCKEC=20 to set/clear bits in DCKE. On JZ4725B, DCKE is read/write, but the zeros written are ignored (at=20 least that's what the documentation says). > -- > ~Vinod Thanks, -Paul =