From patchwork Thu Sep 26 21:55:46 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 2951471 Return-Path: X-Original-To: patchwork-linux-omap@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 28DCB9F244 for ; Thu, 26 Sep 2013 21:57:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9489C20207 for ; Thu, 26 Sep 2013 21:56:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 17A0820211 for ; Thu, 26 Sep 2013 21:56:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754462Ab3IZV4h (ORCPT ); Thu, 26 Sep 2013 17:56:37 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:55742 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754427Ab3IZV4f (ORCPT ); Thu, 26 Sep 2013 17:56:35 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id r8QLtq0w026887; Thu, 26 Sep 2013 16:55:52 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id r8QLtqpl014118; Thu, 26 Sep 2013 16:55:52 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.2.342.3; Thu, 26 Sep 2013 16:55:52 -0500 Received: from joel-laptop.itg.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id r8QLtlp2025638; Thu, 26 Sep 2013 16:55:51 -0500 From: Joel Fernandes To: Sekhar Nori , Vinod Koul , Dan Williams CC: Linux OMAP List , Linux ARM Kernel List , Linux DaVinci Kernel List , Linux Kernel Mailing List , Linux MMC List , Tony Lindgren , Olof Johansson , Nishanth Menon , Pantel Antoniou , Jason Kridner , Koen Kooi , Joel Fernandes Subject: [PATCH v3] ARM: EDMA: Fix clearing of unused list for DT DMA resources Date: Thu, 26 Sep 2013 16:55:46 -0500 Message-ID: <1380232546-821-1-git-send-email-joelf@ti.com> X-Mailer: git-send-email 1.8.1.2 MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-5.9 required=5.0 tests=BAYES_00,KHOP_BIG_TO_CC, RCVD_IN_DNSWL_HI, 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 HWMOD removal for MMC is breaking edma_start as the events are being manually triggered due to unused channel list not being clear. The above issue is fixed by reading the "dmas" property from the DT node if it exists and clearing the bits in the unused channel list if the dma controller used by any device is EDMA. For this purpose we use the of_* helpers to parse the arguments in the dmas phandle list. Also introduced is a minor clean up of a checkpatch error in old code. Reviewed-by: Sekhar Nori Reported-by: Balaji T K Cc: Sekhar Nori Cc: Tony Lindgren Cc: Olof Johansson Cc: Nishanth Menon Cc: Pantel Antoniou Cc: Jason Kridner Cc: Koen Kooi Signed-off-by: Joel Fernandes --- Just resending this patch after discussing with Sekhar and Olof. AM335x is being booted by many users such as the beaglebone community. DT is the only boot method available for all these users. EDMA is required for the operation for many common peripherals in AM335x SoC such as McASP, MMC and Crypto. Although EDMA DT nodes are going in only for 3.13, in reality the kernel has been used for more than a year with EDMA code and out of tree EDMA DTS patches. Hence though the DT nodes are still not in mainline, this patch can be still be considered a critical fix as such and it would be great if it could be included in 3.12-rc release. Thanks. More details about why this broke an existing feature folks were using: Previously the DMA resources for platform devices were being populated through HWMOD, however with the recent clean ups with HWMOD, this data has been moved to Device tree. The EDMA code though is not aware of this so it fails to fetch the DMA resources correctly which it needs to prepare the unused channel list (basically doesn't properly clear the channels that are in use, in the unused list). arch/arm/common/edma.c | 38 +++++++++++++++++++++++++++++++------- 1 file changed, 31 insertions(+), 7 deletions(-) diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c index 117f955..8e1a024 100644 --- a/arch/arm/common/edma.c +++ b/arch/arm/common/edma.c @@ -269,6 +269,11 @@ static const struct edmacc_param dummy_paramset = { .ccnt = 1, }; +static const struct of_device_id edma_of_ids[] = { + { .compatible = "ti,edma3", }, + {} +}; + /*****************************************************************************/ static void map_dmach_queue(unsigned ctlr, unsigned ch_no, @@ -560,14 +565,38 @@ static int reserve_contiguous_slots(int ctlr, unsigned int id, static int prepare_unused_channel_list(struct device *dev, void *data) { struct platform_device *pdev = to_platform_device(dev); - int i, ctlr; + int i, count, ctlr; + struct of_phandle_args dma_spec; + if (dev->of_node) { + count = of_property_count_strings(dev->of_node, "dma-names"); + if (count < 0) + return 0; + for (i = 0; i < count; i++) { + if (of_parse_phandle_with_args(dev->of_node, "dmas", + "#dma-cells", i, + &dma_spec)) + continue; + + if (!of_match_node(edma_of_ids, dma_spec.np)) { + of_node_put(dma_spec.np); + continue; + } + + clear_bit(EDMA_CHAN_SLOT(dma_spec.args[0]), + edma_cc[0]->edma_unused); + of_node_put(dma_spec.np); + } + return 0; + } + + /* For non-OF case */ for (i = 0; i < pdev->num_resources; i++) { if ((pdev->resource[i].flags & IORESOURCE_DMA) && (int)pdev->resource[i].start >= 0) { ctlr = EDMA_CTLR(pdev->resource[i].start); clear_bit(EDMA_CHAN_SLOT(pdev->resource[i].start), - edma_cc[ctlr]->edma_unused); + edma_cc[ctlr]->edma_unused); } } @@ -1762,11 +1791,6 @@ static int edma_probe(struct platform_device *pdev) return 0; } -static const struct of_device_id edma_of_ids[] = { - { .compatible = "ti,edma3", }, - {} -}; - static struct platform_driver edma_driver = { .driver = { .name = "edma",