From patchwork Thu Oct 17 17:45:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11196685 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 37676912 for ; Thu, 17 Oct 2019 17:52:10 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 16BD42089C for ; Thu, 17 Oct 2019 17:52:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="rtdGgn5j" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 16BD42089C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=YPwD7VAftQLEMrw3ypWp6F1XEdcl3hxC4JTQeJsy9qk=; b=rtdGgn5jMowKiy DTpDAXjBptliY+Xj8JE+Ok7/KnNhgBBVtCIcg8X/iyvyakSHq7rIEFBnUKlIDsyP7SfpSyOuhagif a7NQMWyHbwnlfVlOV9eCPuiJhDzCy0Q69e3qRxd7QUAXJeqYsLHNQpfqyQNVNwQdSRO9hg7MBfVyu Nqz24JKzs7V9BxrDboyfP9k654vPDAJ2zwdsbaVFQ4sKHHG/GViYsyLwakcxR3tyhF8pfc+61fljE ZeN6IPKbkeNMgvUWKNSPEEH020qxgm+XLTWSzkp1QbU284FBVdortKMlLG9Azh4jtcKteG62U/h27 um+rhlHwrobaTr9L6VCQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iL9wW-000458-P3; Thu, 17 Oct 2019 17:52:08 +0000 Received: from [2001:4bb8:18c:d7b:c70:4a89:bc61:3] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iL9qy-0005q9-PO; Thu, 17 Oct 2019 17:46:25 +0000 From: Christoph Hellwig To: Arnd Bergmann , Guo Ren , Michal Simek , Greentime Hu , Vincent Chen , Guan Xuetao , x86@kernel.org Subject: [PATCH 10/21] asm-generic: ioremap_uc should behave the same with and without MMU Date: Thu, 17 Oct 2019 19:45:43 +0200 Message-Id: <20191017174554.29840-11-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191017174554.29840-1-hch@lst.de> References: <20191017174554.29840-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, openrisc@lists.librecores.org, linux-mtd@lists.infradead.org, linux-alpha@vger.kernel.org, sparclinux@vger.kernel.org, nios2-dev@lists.rocketboards.org, linux-riscv@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Whatever reason there is for the existence of ioremap_uc, and the fact that it returns NULL by default on architectures with an MMU applies equally to nommu architectures, so don't provide different defaults. In practice the difference is meaningless as the only portable driver that uses ioremap_uc is atyfb which probably doesn't show up on nommu devices. Signed-off-by: Christoph Hellwig --- include/asm-generic/io.h | 36 ++++++++++++++++-------------------- 1 file changed, 16 insertions(+), 20 deletions(-) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index d02806513670..a98ed6325727 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -935,18 +935,7 @@ static inline void *phys_to_virt(unsigned long address) * defined your own ioremap_*() variant you must then declare your own * ioremap_*() variant as defined to itself to avoid the default NULL return. */ - -#ifdef CONFIG_MMU - -#ifndef ioremap_uc -#define ioremap_uc ioremap_uc -static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size) -{ - return NULL; -} -#endif - -#else /* !CONFIG_MMU */ +#ifndef CONFIG_MMU /* * Change "struct page" to physical address. @@ -980,14 +969,6 @@ static inline void __iomem *ioremap_nocache(phys_addr_t offset, size_t size) } #endif -#ifndef ioremap_uc -#define ioremap_uc ioremap_uc -static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size) -{ - return ioremap_nocache(offset, size); -} -#endif - #ifndef ioremap_wc #define ioremap_wc ioremap_wc static inline void __iomem *ioremap_wc(phys_addr_t offset, size_t size) @@ -1004,6 +985,21 @@ static inline void __iomem *ioremap_wt(phys_addr_t offset, size_t size) } #endif +/* + * ioremap_uc is special in that we do require an explicit architecture + * implementation. In general you do now want to use this function in a + * driver and use plain ioremap, which is uncached by default. Similarly + * architectures should not implement it unless they have a very good + * reason. + */ +#ifndef ioremap_uc +#define ioremap_uc ioremap_uc +static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size) +{ + return NULL; +} +#endif + #ifdef CONFIG_HAS_IOPORT_MAP #ifndef CONFIG_GENERIC_IOMAP #ifndef ioport_map