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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 7E175C32771 for ; Mon, 27 Jan 2020 07:23:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55B4020702 for ; Mon, 27 Jan 2020 07:23:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="ZkdUqd2z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726191AbgA0HXK (ORCPT ); Mon, 27 Jan 2020 02:23:10 -0500 Received: from mail-vk1-f193.google.com ([209.85.221.193]:36294 "EHLO mail-vk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725765AbgA0HXJ (ORCPT ); Mon, 27 Jan 2020 02:23:09 -0500 Received: by mail-vk1-f193.google.com with SMTP id i4so2372081vkc.3 for ; Sun, 26 Jan 2020 23:23:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=9Zs7ordlPu6oLMie0ztw+ViABr97RTMvxSHDoSvg2y8=; b=ZkdUqd2zKSeWdVR91y36SdzJKYZWn6y3ItuefmZXZQ65FE7TOnAneczRyXuYZ73Q09 dxyrhyivxIhtQcR2Niso9FYPdVIMx7MpX3rk2ZMJ0xzAOkFCuRZxaewbU0pVz0EnbFTf RwBf8kQhz4qiuQMkW/EoW11SdohZV+sqIYsjjZXPVt4bwAZ+59aKtKpOT4x+mz3DATbJ l8XSQjy40AFGHpBJmIXEwQ54J73jRsoZi6Gy68//Pw8gcbJwFQ77p8u1E4EGmL7UpgvB JZ/1N0idA75Y+pP1l/5Pl9EJcLI54QRiC4BtLNNHuB7wI92mBOYSLhRXl9HWHp1fHViD 6DQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=9Zs7ordlPu6oLMie0ztw+ViABr97RTMvxSHDoSvg2y8=; b=PinzcFVdeaTDK1Da1yVSSHbTM05mAze89zHpVMXpjRRBbrZtfB1YNhXAoNBBcwOM/m IqzSj/jfqvJnku7MdfM2m7Xoz7mHR+48yotSWHzGb4LYAVQFZR47g5/AVSebQWoTj4uU Nzx3z+uGDkonIBXq/6mFYjqQma5wyUDel7LjNl1oWQneBJl2Gp35nQgu/l+qB4P2U8gU GnwzxF3QWSRjxYrTYp+pnMovuvi13oiqKDlqkTH45Ujzcr7j0vaSMYFD3Vh/je2RYAiP sJWUiqKHMloEffRrBcY1se8j+cAoWClBslO7qkdp+D6lWHDrgbWb6lIDkiQzOexjkJQW xfjQ== X-Gm-Message-State: APjAAAUZH0YDTSJTabmzGn55fvog3ghL0r6B3GZ62C4PFj8wy8pIE2dh dW4vFqXmH9Z+sYzdbflt5F9uqPHl8Xl1KLZagmAbLRNs X-Google-Smtp-Source: APXvYqz4OQZA/2kIUqEb6B2klRTdDoZkhD2PvmDkLDercb9w5oGLFffYnzmHjIgmSkCuBSvVCAvCAxfvm+k7OKQr2M8= X-Received: by 2002:a1f:434b:: with SMTP id q72mr8497371vka.53.1580109787392; Sun, 26 Jan 2020 23:23:07 -0800 (PST) MIME-Version: 1.0 References: <20200126115247.13402-1-mpe@ellerman.id.au> In-Reply-To: <20200126115247.13402-1-mpe@ellerman.id.au> From: Ulf Hansson Date: Mon, 27 Jan 2020 08:22:29 +0100 Message-ID: Subject: Re: [PATCH] of: Add OF_DMA_DEFAULT_COHERENT & select it on powerpc To: Michael Ellerman Cc: Rob Herring , DTML , Linux Kernel Mailing List , Christoph Hellwig , Christian Zigotzky , linuxppc-dev@ozlabs.org Content-Type: text/plain; charset="UTF-8" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Sun, 26 Jan 2020 at 12:53, Michael Ellerman wrote: > > There's an OF helper called of_dma_is_coherent(), which checks if a > device has a "dma-coherent" property to see if the device is coherent > for DMA. > > But on some platforms devices are coherent by default, and on some > platforms it's not possible to update existing device trees to add the > "dma-coherent" property. > > So add a Kconfig symbol to allow arch code to tell > of_dma_is_coherent() that devices are coherent by default, regardless > of the presence of the property. > > Select that symbol on powerpc when NOT_COHERENT_CACHE is not set, ie. > when the system has a coherent cache. > > Fixes: 92ea637edea3 ("of: introduce of_dma_is_coherent() helper") > Cc: stable@vger.kernel.org # v3.16+ > Reported-by: Christian Zigotzky > Tested-by: Christian Zigotzky > Signed-off-by: Michael Ellerman Thanks Michael for helping out fixing and this! The patch looks good to me. Reviewed-by: Ulf Hansson Kind regards Uffe > --- > arch/powerpc/Kconfig | 1 + > drivers/of/Kconfig | 4 ++++ > drivers/of/address.c | 6 +++++- > 3 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 1ec34e16ed65..19f5aa8ac9a3 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -238,6 +238,7 @@ config PPC > select NEED_DMA_MAP_STATE if PPC64 || NOT_COHERENT_CACHE > select NEED_SG_DMA_LENGTH > select OF > + select OF_DMA_DEFAULT_COHERENT if !NOT_COHERENT_CACHE > select OF_EARLY_FLATTREE > select OLD_SIGACTION if PPC32 > select OLD_SIGSUSPEND > diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig > index 37c2ccbefecd..d91618641be6 100644 > --- a/drivers/of/Kconfig > +++ b/drivers/of/Kconfig > @@ -103,4 +103,8 @@ config OF_OVERLAY > config OF_NUMA > bool > > +config OF_DMA_DEFAULT_COHERENT > + # arches should select this if DMA is coherent by default for OF devices > + bool > + > endif # OF > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 99c1b8058559..e8a39c3ec4d4 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -995,12 +995,16 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz > * @np: device node > * > * It returns true if "dma-coherent" property was found > - * for this device in DT. > + * for this device in the DT, or if DMA is coherent by > + * default for OF devices on the current platform. > */ > bool of_dma_is_coherent(struct device_node *np) > { > struct device_node *node = of_node_get(np); > > + if (IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT)) > + return true; > + > while (node) { > if (of_property_read_bool(node, "dma-coherent")) { > of_node_put(node); > -- > 2.21.1 >