From patchwork Tue May 16 05:22:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oza Pawandeep X-Patchwork-Id: 762792 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3wRm6p0Zpvz9s85 for ; Tue, 16 May 2017 15:22:42 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=broadcom.com header.i=@broadcom.com header.b="Rmdq4utQ"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751365AbdEPFWd (ORCPT ); Tue, 16 May 2017 01:22:33 -0400 Received: from mail-wm0-f42.google.com ([74.125.82.42]:38468 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751017AbdEPFWa (ORCPT ); Tue, 16 May 2017 01:22:30 -0400 Received: by mail-wm0-f42.google.com with SMTP id v15so75931205wmv.1 for ; Mon, 15 May 2017 22:22:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=LSUC8K+Z2J0IkqbGSLdNSGCEWqPtC95cppc5FKr1XYk=; b=Rmdq4utQUi01onDbGwazE66M5jkNkOuPtET2LIT8NuFXA/IhS2F+p9MaIWz2ULD8DK jvMTwdRYEzXeJze+eaZLLjvDawaLxZmEQPn7yFwMQ9qwy/K4nsB5MTzJ6gFm83twmGV3 NDuxd5xAugUwGBI6stBmY4JzsAf3xr1Qd3c7Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=LSUC8K+Z2J0IkqbGSLdNSGCEWqPtC95cppc5FKr1XYk=; b=TBrzTWkKRmZ8wf2povptVrO55EMI/ur6HGC/F3qZ9fl11CYWE6d5wWJJSUaqiih4uj lpANQwlz09V1RrdCqGTOJQwLv9S+pUBIAtV2fjLt02Q5Brnt6UZgk2gq2zPw0uMVbKuf BbqtH5APbvMbE7ORBzP2hSTHV5fSGvR0wzN6U4AnNqvP0PiVfEEGlgCN9e2zQsIJy2oK eFPJ33VLhAwO+dy8TCul3iM4geAge02t/P2B11zYQN4CwNAl1qwjGmo3GQH1Tmlvmvd4 XicWNuJJi2zKDfOkVQ/Zl0YZLZXEZa+yX4bsCNnOqzExuFYF9e0ZH9Ba8LHaFwyKanaj dXBA== X-Gm-Message-State: AODbwcA/CKjV6nmMFZG36YRR5w65FTyH3j6Sz5EnquT/dl5nK7lT15Y4 YXbEHBwAl/Wcc8/z X-Received: by 10.28.52.139 with SMTP id b133mr5571207wma.36.1494912148360; Mon, 15 May 2017 22:22:28 -0700 (PDT) Received: from anjanavk-OptiPlex-7010.dhcp.avagotech.net ([192.19.237.250]) by smtp.gmail.com with ESMTPSA id m201sm1053073wmd.15.2017.05.15.22.22.22 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 15 May 2017 22:22:27 -0700 (PDT) From: Oza Pawandeep To: Joerg Roedel , Robin Murphy Cc: iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, Oza Pawandeep , Oza Pawandeep Subject: [PATCH v6 1/3] of/pci/dma: fix DMA configuration for PCI masters Date: Tue, 16 May 2017 10:52:05 +0530 Message-Id: <1494912127-12890-2-git-send-email-oza.oza@broadcom.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1494912127-12890-1-git-send-email-oza.oza@broadcom.com> References: <1494912127-12890-1-git-send-email-oza.oza@broadcom.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org current device framework and OF framework integration assumes dma-ranges in a way where memory-mapped devices define their dma-ranges. (child-bus-address, parent-bus-address, length). of_dma_configure is specifically written to take care of memory mapped devices. but no implementation exists for pci to take care of pcie based memory ranges. for e.g. iproc based SOCs and other SOCs(suc as rcar) have PCI world dma-ranges. dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; this patch serves following: 1) exposes interface to the pci host driver for their inbound memory ranges 2) provide an interface to callers such as of_dma_get_ranges. so then the returned size get best possible (largest) dma_mask. because PCI RC drivers do not call APIs such as dma_set_coherent_mask() and hence rather it shows its addressing capabilities based on dma-ranges. for e.g. dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; we should get dev->coherent_dma_mask=0x7fffffffff. 3) this patch handles multiple inbound windows and dma-ranges. it is left to the caller, how it wants to use them. the new function returns the resources in a standard and unform way 4) this way the callers of for e.g. of_dma_get_ranges does not need to change. Signed-off-by: Oza Pawandeep diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 0ee42c3..4005ed3 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -283,6 +283,101 @@ int of_pci_get_host_bridge_resources(struct device_node *dev, return err; } EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources); + +/** + * of_pci_get_dma_ranges - Parse PCI host bridge inbound resources from DT + * @np: device node of the host bridge having the dma-ranges property + * @resources: list where the range of resources will be added after DT parsing + * + * It is the caller's job to free the @resources list. + * + * This function will parse the "dma-ranges" property of a + * PCI host bridge device node and setup the resource mapping based + * on its content. + * + * It returns zero if the range parsing has been successful or a standard error + * value if it failed. + */ + +int of_pci_get_dma_ranges(struct device_node *dn, struct list_head *resources) +{ + struct device_node *node = of_node_get(dn); + int rlen; + int pna = of_n_addr_cells(node); + const int na = 3, ns = 2; + int np = pna + na + ns; + int ret = 0; + struct resource *res; + const u32 *dma_ranges; + struct of_pci_range range; + + if (!node) + return -EINVAL; + + while (1) { + dma_ranges = of_get_property(node, "dma-ranges", &rlen); + + /* Ignore empty ranges, they imply no translation required. */ + if (dma_ranges && rlen > 0) + break; + + /* no dma-ranges, they imply no translation required. */ + if (!dma_ranges) + break; + + node = of_get_next_parent(node); + + if (!node) + break; + } + + if (!dma_ranges) { + pr_debug("pcie device has no dma-ranges defined for node(%s)\n", + dn->full_name); + ret = -EINVAL; + goto out; + } + + while ((rlen -= np * 4) >= 0) { + range.pci_space = dma_ranges[0]; + range.pci_addr = of_read_number(dma_ranges + 1, ns); + range.cpu_addr = of_translate_dma_address(node, + dma_ranges + na); + range.size = of_read_number(dma_ranges + pna + na, ns); + + dma_ranges += np; + + /* + * If we failed translation or got a zero-sized region + * then skip this range. + */ + if (range.cpu_addr == OF_BAD_ADDR || range.size == 0) + continue; + + res = kzalloc(sizeof(struct resource), GFP_KERNEL); + if (!res) { + ret = -ENOMEM; + goto parse_failed; + } + + ret = of_pci_range_to_resource(&range, dn, res); + if (ret) { + kfree(res); + continue; + } + + pci_add_resource_offset(resources, res, + res->start - range.pci_addr); + } + return ret; + +parse_failed: + pci_free_resource_list(resources); +out: + of_node_put(node); + return ret; +} +EXPORT_SYMBOL_GPL(of_pci_get_dma_ranges); #endif /* CONFIG_OF_ADDRESS */ #ifdef CONFIG_PCI_MSI diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index 0e0974e..617b90d 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -76,6 +76,7 @@ static inline void of_pci_check_probe_only(void) { } int of_pci_get_host_bridge_resources(struct device_node *dev, unsigned char busno, unsigned char bus_max, struct list_head *resources, resource_size_t *io_base); +int of_pci_get_dma_ranges(struct device_node *np, struct list_head *resources); #else static inline int of_pci_get_host_bridge_resources(struct device_node *dev, unsigned char busno, unsigned char bus_max, @@ -83,6 +84,12 @@ static inline int of_pci_get_host_bridge_resources(struct device_node *dev, { return -EINVAL; } + +static inline int of_pci_get_dma_ranges(struct device_node *np, + struct list_head *resources) +{ + return -EINVAL; +} #endif #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI)