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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B15ECCA480 for ; Wed, 6 Jul 2022 23:15:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234255AbiGFXP6 (ORCPT ); Wed, 6 Jul 2022 19:15:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229768AbiGFXPz (ORCPT ); Wed, 6 Jul 2022 19:15:55 -0400 Received: from gloria.sntech.de (gloria.sntech.de [185.11.138.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 856B6DD8; Wed, 6 Jul 2022 16:15:53 -0700 (PDT) Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=phil.lan) by gloria.sntech.de with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1o9EFD-0002yn-C5; Thu, 07 Jul 2022 01:15:43 +0200 From: Heiko Stuebner To: palmer@dabbelt.com, paul.walmsley@sifive.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, wefu@redhat.com, guoren@kernel.org, cmuellner@linux.com, philipp.tomsich@vrull.eu, hch@lst.de, samuel@sholland.org, atishp@atishpatra.org, anup@brainfault.org, mick@ics.forth.gr, robh+dt@kernel.org, krzk+dt@kernel.org, devicetree@vger.kernel.org, drew@beagleboard.org, rdunlap@infradead.org, Heiko Stuebner , Rob Herring Subject: [PATCH v7 1/4] of: also handle dma-noncoherent in of_dma_is_coherent() Date: Thu, 7 Jul 2022 01:15:33 +0200 Message-Id: <20220706231536.2041855-2-heiko@sntech.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220706231536.2041855-1-heiko@sntech.de> References: <20220706231536.2041855-1-heiko@sntech.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org of_dma_is_coherent() currently expects the architecture to be non-coherent and some devices being coherent getting marked as such with the dma-coherent devicetree property. For PowerPC CONFIG_OF_DMA_DEFAULT_COHERENT was added which currently makes of_dma_is_coherent() always return true but doesn't handle the case of the architecture being coherent but some devices not. So modify the function to also check for dma-noncoherent and set a suitable default return value. If CONFIG_OF_DMA_DEFAULT_COHERENT is set the value starts with true and finding dma-noncoherent will set it to false and without CONFIG_OF_DMA_DEFAULT_COHERENT, the behaviour is reversed. Reviewed-by: Christoph Hellwig Reviewed-by: Rob Herring Reviewed-by: Guo Ren Signed-off-by: Heiko Stuebner --- drivers/of/address.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index 94f017d808c4..96f0a12e507c 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -1045,26 +1045,29 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np) * * It returns true if "dma-coherent" property was found * for this device in the DT, or if DMA is coherent by - * default for OF devices on the current platform. + * default for OF devices on the current platform and no + * "dma-noncoherent" property was found for this device. */ bool of_dma_is_coherent(struct device_node *np) { struct device_node *node; - - if (IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT)) - return true; + bool is_coherent = IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT); node = of_node_get(np); while (node) { if (of_property_read_bool(node, "dma-coherent")) { - of_node_put(node); - return true; + is_coherent = true; + break; + } + if (of_property_read_bool(node, "dma-noncoherent")) { + is_coherent = false; + break; } node = of_get_next_dma_parent(node); } of_node_put(node); - return false; + return is_coherent; } EXPORT_SYMBOL_GPL(of_dma_is_coherent); -- 2.35.1