From patchwork Fri Apr 2 09:05:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hector Martin X-Patchwork-Id: 414581 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, 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 D58F9C43462 for ; Fri, 2 Apr 2021 09:07:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BAFA360724 for ; Fri, 2 Apr 2021 09:07:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234938AbhDBJHd (ORCPT ); Fri, 2 Apr 2021 05:07:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234867AbhDBJHX (ORCPT ); Fri, 2 Apr 2021 05:07:23 -0400 Received: from mail.marcansoft.com (marcansoft.com [IPv6:2a01:298:fe:f::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 662ACC0613E6; Fri, 2 Apr 2021 02:07:19 -0700 (PDT) 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 B558B4272F; Fri, 2 Apr 2021 09:07:11 +0000 (UTC) From: Hector Martin To: linux-arm-kernel@lists.infradead.org Cc: Hector Martin , Marc Zyngier , Rob Herring , Arnd Bergmann , Olof Johansson , Krzysztof Kozlowski , Mark Kettenis , Tony Lindgren , Mohamed Mediouni , Stan Skowronek , Alexander Graf , Will Deacon , Linus Walleij , Mark Rutland , Andy Shevchenko , Jonathan Corbet , Catalin Marinas , Christoph Hellwig , "David S. Miller" , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 12/18] of/address: Add infrastructure to declare MMIO as non-posted Date: Fri, 2 Apr 2021 18:05:36 +0900 Message-Id: <20210402090542.131194-13-marcan@marcan.st> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210402090542.131194-1-marcan@marcan.st> References: <20210402090542.131194-1-marcan@marcan.st> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This implements the 'nonposted-mmio' boolean property. Placing this property in a bus marks all direct child devices as requiring non-posted MMIO mappings. If no such property is found, the default is posted MMIO. of_mmio_is_nonposted() performs this check 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 builds that support Apple ARM platforms, as an optimization. Reviewed-by: Linus Walleij Signed-off-by: Hector Martin Reviewed-by: Rob Herring --- drivers/of/address.c | 43 ++++++++++++++++++++++++++++++++++++-- include/linux/of_address.h | 1 + 2 files changed, 42 insertions(+), 2 deletions(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index 73ddf2540f3f..6485cc536e81 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 +1104,32 @@ bool of_dma_is_coherent(struct device_node *np) return false; } EXPORT_SYMBOL_GPL(of_dma_is_coherent); + +/** + * 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. + * + * This is currently only enabled on builds that support Apple ARM devices, as + * an optimization. + */ +bool of_mmio_is_nonposted(struct device_node *np) +{ + struct device_node *parent; + bool nonposted; + + if (!IS_ENABLED(CONFIG_ARCH_APPLE)) + return false; + + parent = of_get_parent(np); + if (!parent) + return false; + + nonposted = of_property_read_bool(parent, "nonposted-mmio"); + + of_node_put(parent); + return nonposted; +} +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)