From patchwork Tue Oct 29 06:48:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1185872 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="iTf8yYRX"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 472Mk81n2Tz9sPV for ; Tue, 29 Oct 2019 17:53:36 +1100 (AEDT) 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=gffz8wtD85JX0l/2Ggbm9eyQO7U3BmtdVtEx8dOMB6o=; b=iTf8yYRXt2t4ls YKUQMbv/GZtPrDEXSWRWqYPRwH50TjfdfG2Je0JPZsywD13K8gCBf0QhYZLRneT8DVtpvN1oROTMq lNPpG34i5ijQqoVfPIOhQ+e8u8HfUhVbHwx80z7eGjyNZ1sepz37XYSPS+oR5u+9DTXQmk3O1XfWo JmPgB09K+/ZrCMRCHKWpel5FFhfi1FSewURxyBUE1yDdM5h+1oltk80LYn2yK0EJvhI/BMVJU8BJO 2aYyt5xf8zj3HT1WMM0bao8A9foaCscmojTtdFtP8CjdfCWfm+Seqx/JnpXPOuIu77we9JYSLIs5t 13KBMHj1zG4oC9l9XFow==; 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 1iPLNm-0000k5-2N; Tue, 29 Oct 2019 06:53:34 +0000 Received: from [2001:4bb8:18c:c7d:c70:4a89:bc61:2] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iPLJT-0003p3-Ev; Tue, 29 Oct 2019 06:49:07 +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: Tue, 29 Oct 2019 07:48:23 +0100 Message-Id: <20191029064834.23438-11-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191029064834.23438-1-hch@lst.de> References: <20191029064834.23438-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on Synopsys ARC Processors 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-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.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 Reviewed-by: Palmer Dabbelt Reviewed-by: Arnd Bergmann --- 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