From patchwork Sat Apr 19 14:32:47 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Santosh Shilimkar X-Patchwork-Id: 4020081 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 8F91F9F319 for ; Sat, 19 Apr 2014 14:36:50 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A16512021B for ; Sat, 19 Apr 2014 14:36:49 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AD0E820212 for ; Sat, 19 Apr 2014 14:36:48 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WbWLs-0007Se-6G; Sat, 19 Apr 2014 14:34:44 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WbWLX-0007LZ-D5 for linux-arm-kernel@lists.infradead.org; Sat, 19 Apr 2014 14:34:24 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id s3JEXlm1014708; Sat, 19 Apr 2014 09:33:47 -0500 Received: from DFLE73.ent.ti.com (dfle73.ent.ti.com [128.247.5.110]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id s3JEXkjN012784; Sat, 19 Apr 2014 09:33:47 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DFLE73.ent.ti.com (128.247.5.110) with Microsoft SMTP Server id 14.3.174.1; Sat, 19 Apr 2014 09:33:46 -0500 Received: from ula0393909.am.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id s3JEXT30019097; Sat, 19 Apr 2014 09:33:46 -0500 From: Santosh Shilimkar To: Subject: [PATCH v2 2/7] of: introduce of_dma_get_range() helper Date: Sat, 19 Apr 2014 10:32:47 -0400 Message-ID: <1397917972-6293-3-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1397917972-6293-1-git-send-email-santosh.shilimkar@ti.com> References: <1397917972-6293-1-git-send-email-santosh.shilimkar@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140419_073423_538151_5F7574D3 X-CRM114-Status: GOOD ( 15.57 ) X-Spam-Score: -5.7 (-----) Cc: devicetree@vger.kernel.org, Grygorii Strashko , Russell King , Arnd Bergmann , Greg Kroah-Hartman , Linus Walleij , Grant Likely , Rob Herring , Santosh Shilimkar , Catalin Marinas , Olof Johansson , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Grygorii Strashko The of_dma_get_range() allows to find "dma-range" property for the specified device and parse it. dma-ranges format: DMA addr (dma_addr) : naddr cells CPU addr (phys_addr_t) : pna cells size : nsize cells Cc: Greg Kroah-Hartman Cc: Russell King Cc: Arnd Bergmann Cc: Olof Johansson Cc: Grant Likely Cc: Rob Herring Cc: Catalin Marinas Cc: Linus Walleij Signed-off-by: Grygorii Strashko Signed-off-by: Santosh Shilimkar --- drivers/of/platform.c | 85 +++++++++++++++++++++++++++++++++++++++++++ include/linux/of_platform.h | 8 ++++ 2 files changed, 93 insertions(+) diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 404d1da..2265a55 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -485,4 +485,89 @@ int of_platform_populate(struct device_node *root, return rc; } EXPORT_SYMBOL_GPL(of_platform_populate); + +/** + * of_dma_get_range - Get DMA range info + * @np: device node to get DMA range info + * @dma_addr: pointer to store initial DMA address of DMA range + * @paddr: pointer to store initial CPU address of DMA range + * @size: pointer to store size of DMA range + * + * Look in bottom up direction for the first "dma-range" property + * and parse it. + * dma-ranges format: + * DMA addr (dma_addr) : naddr cells + * CPU addr (phys_addr_t) : pna cells + * size : nsize cells + * + * It returns -ENODEV if "dma-ranges" property was not found + * for this device in DT. + */ +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size) +{ + struct device_node *node = np; + const u32 *ranges = NULL; + int len, naddr, nsize, pna; + int ret = 0; + + if (!node) + return -EINVAL; + + while (1) { + naddr = of_n_addr_cells(node); + nsize = of_n_size_cells(node); + node = of_get_next_parent(node); + if (!node) + break; + + ranges = of_get_property(node, "dma-ranges", &len); + + /* Ignore empty ranges, they imply no translation required */ + if (ranges && len > 0) + break; + + /* + * At least empty ranges has to be defined for parent node if + * DMA is supported + */ + if (!ranges) + break; + } + + if (!ranges) { + pr_debug("%s: no dma-ranges found for node(%s)\n", + __func__, np->full_name); + ret = -ENODEV; + goto out; + } + + len /= sizeof(u32); + + pna = of_n_addr_cells(node); + + /* dma-ranges format: + * DMA addr : naddr cells + * CPU addr : pna cells + * size : nsize cells + */ + *dma_addr = of_read_number(ranges, naddr); + *paddr = of_translate_dma_address(np, ranges); + if (*paddr == OF_BAD_ADDR) { + pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n", + __func__, dma_addr, np->full_name); + ret = -EINVAL; + } + + *size = of_read_number(ranges + naddr + pna, nsize); + + pr_debug("dma_addr(%pad) cpu_addr(%pa) size(%pa)\n", + dma_addr, paddr, size); + +out: + of_node_put(node); + + return ret; +} +EXPORT_SYMBOL_GPL(of_dma_get_range); #endif /* CONFIG_OF_ADDRESS */ diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 05cb4a9..ba7d3dc 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -72,6 +72,8 @@ extern int of_platform_populate(struct device_node *root, const struct of_device_id *matches, const struct of_dev_auxdata *lookup, struct device *parent); +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size); #else static inline int of_platform_populate(struct device_node *root, const struct of_device_id *matches, @@ -80,6 +82,12 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } + +static inline int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size) +{ + return -ENODEV; +} #endif #endif /* _LINUX_OF_PLATFORM_H */