From patchwork Mon Feb 15 12:17:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hector Martin X-Patchwork-Id: 12088055 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=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 5BC8CC433DB for ; Mon, 15 Feb 2021 12:21:46 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 1302E61606 for ; Mon, 15 Feb 2021 12:21:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1302E61606 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=marcan.st Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.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=nVnmZ3D2WUgW++DEefqC7VQ4gz7MIIkT+C1kaX034to=; b=yaglaW7UZ82anEj9+3Wsf78nh rn3y7BRwB3CS9g9CzuQWpPrWYy8k/doTkFbgAyRNhMw33i642mTKl6ckkK55D4PU3tMUmQNlKaukC tAAjNEvnzLWgJNJou6CCpxCwQ5Rf6G1g0xlgWhDl9H33VwT2uwQ95c+6TqgXbr8ge2pa+x8ujwn6K q4yYgC/jzM8EBgC2/ILX/EHlyRNj+u7l3EDQSVIXD+pANVvJRiuE7ROtbjK/OqHW/TzakRvU9BmVv A2XFBeWUA2DeNQYtAC5MC2Y1p3rGn2HGCPj4NjUpIaw2pgJGiWkf+DXFTYv3glbLPa3gDGmQF1ho/ Yuj5Biz9Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lBcrK-0006Aj-62; Mon, 15 Feb 2021 12:20:10 +0000 Received: from marcansoft.com ([212.63.210.85] helo=mail.marcansoft.com) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lBcpq-0005UA-UN for linux-arm-kernel@lists.infradead.org; Mon, 15 Feb 2021 12:18:42 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (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) (Authenticated sender: hector@marcansoft.com) by mail.marcansoft.com (Postfix) with ESMTPSA id B2FDA424BA; Mon, 15 Feb 2021 12:18:33 +0000 (UTC) From: Hector Martin To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 12/25] of/address: Add infrastructure to declare MMIO as non-posted Date: Mon, 15 Feb 2021 21:17:00 +0900 Message-Id: <20210215121713.57687-13-marcan@marcan.st> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210215121713.57687-1-marcan@marcan.st> References: <20210215121713.57687-1-marcan@marcan.st> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210215_071839_378568_4C4EB8E7 X-CRM114-Status: GOOD ( 21.66 ) 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: Mark Rutland , Arnd Bergmann , Rob Herring , Tony Lindgren , Marc Zyngier , Linus Walleij , Hector Martin , linux-kernel@vger.kernel.org, Krzysztof Kozlowski , devicetree@vger.kernel.org, Alexander Graf , Olof Johansson , Mohamed Mediouni , Stan Skowronek , Will Deacon , Mark Kettenis Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This implements the 'nonposted-mmio' and 'posted-mmio' boolean properties. Placing these properties in a bus marks all child devices as requiring non-posted or posted MMIO mappings. If no such properties are found, the default is posted MMIO. of_mmio_is_nonposted() performs the tree walking to determine if a given device has requested non-posted MMIO. of_address_to_resource() uses this to set the IORESOURCE_MEM_NONPOSTED flag on resources that require non-posted MMIO. of_iomap() and of_io_request_and_map() then use this flag to pick the correct ioremap() variant. This mechanism is currently restricted to Apple ARM platforms, as an optimization. Signed-off-by: Hector Martin --- drivers/of/address.c | 72 ++++++++++++++++++++++++++++++++++++-- include/linux/of_address.h | 1 + 2 files changed, 71 insertions(+), 2 deletions(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index 73ddf2540f3f..6114dceb1ba6 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -847,6 +847,9 @@ static int __of_address_to_resource(struct device_node *dev, return -EINVAL; memset(r, 0, sizeof(struct resource)); + if (of_mmio_is_nonposted(dev)) + flags |= IORESOURCE_MEM_NONPOSTED; + r->start = taddr; r->end = taddr + size - 1; r->flags = flags; @@ -896,7 +899,10 @@ void __iomem *of_iomap(struct device_node *np, int index) if (of_address_to_resource(np, index, &res)) return NULL; - return ioremap(res.start, resource_size(&res)); + if (res.flags & IORESOURCE_MEM_NONPOSTED) + return ioremap_np(res.start, resource_size(&res)); + else + return ioremap(res.start, resource_size(&res)); } EXPORT_SYMBOL(of_iomap); @@ -928,7 +934,11 @@ void __iomem *of_io_request_and_map(struct device_node *np, int index, if (!request_mem_region(res.start, resource_size(&res), name)) return IOMEM_ERR_PTR(-EBUSY); - mem = ioremap(res.start, resource_size(&res)); + if (res.flags & IORESOURCE_MEM_NONPOSTED) + mem = ioremap_np(res.start, resource_size(&res)); + else + mem = ioremap(res.start, resource_size(&res)); + if (!mem) { release_mem_region(res.start, resource_size(&res)); return IOMEM_ERR_PTR(-ENOMEM); @@ -1094,3 +1104,61 @@ bool of_dma_is_coherent(struct device_node *np) return false; } EXPORT_SYMBOL_GPL(of_dma_is_coherent); + +static bool of_nonposted_mmio_quirk(void) +{ + if (IS_ENABLED(CONFIG_ARCH_APPLE)) { + /* To save cycles, we cache the result for global "Apple ARM" setting */ + static int quirk_state = -1; + + /* Make quirk cached */ + if (quirk_state < 0) + quirk_state = of_machine_is_compatible("apple,arm-platform"); + return !!quirk_state; + } + return false; +} + +/** + * of_mmio_is_nonposted - Check if device uses non-posted MMIO + * @np: device node + * + * Returns true if the "nonposted-mmio" property was found for + * the device's bus or a parent. "posted-mmio" has the opposite + * effect, terminating recursion and overriding any + * "nonposted-mmio" properties in parent buses. + * + * Recursion terminates if reach a non-translatable boundary + * (a node without a 'ranges' property). + * + * This is currently only enabled on Apple ARM devices, as an + * optimization. + */ +bool of_mmio_is_nonposted(struct device_node *np) +{ + struct device_node *node; + struct device_node *parent; + + if (!of_nonposted_mmio_quirk()) + return false; + + node = of_get_parent(np); + + while (node) { + if (!of_property_read_bool(node, "ranges")) { + break; + } else if (of_property_read_bool(node, "nonposted-mmio")) { + of_node_put(node); + return true; + } else if (of_property_read_bool(node, "posted-mmio")) { + break; + } + parent = of_get_parent(node); + of_node_put(node); + node = parent; + } + + of_node_put(node); + return false; +} +EXPORT_SYMBOL_GPL(of_mmio_is_nonposted); diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 88bc943405cd..88f6333fee6c 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -62,6 +62,7 @@ extern struct of_pci_range *of_pci_range_parser_one( struct of_pci_range_parser *parser, struct of_pci_range *range); extern bool of_dma_is_coherent(struct device_node *np); +extern bool of_mmio_is_nonposted(struct device_node *np); #else /* CONFIG_OF_ADDRESS */ static inline void __iomem *of_io_request_and_map(struct device_node *device, int index, const char *name)