From patchwork Mon Apr 11 13:29:08 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 8801291 Return-Path: X-Original-To: patchwork-dmaengine@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0C71E9FBEA for ; Mon, 11 Apr 2016 13:29:48 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0AD5A2034B for ; Mon, 11 Apr 2016 13:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB0FC202F8 for ; Mon, 11 Apr 2016 13:29:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932168AbcDKN3i (ORCPT ); Mon, 11 Apr 2016 09:29:38 -0400 Received: from 212-186-180-163.dynamic.surfer.at ([212.186.180.163]:50447 "EHLO cgate.sperl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932110AbcDKN3g (ORCPT ); Mon, 11 Apr 2016 09:29:36 -0400 Received: from rasp3a.intern.sperl.org (account martin@sperl.org [10.10.10.43] verified) by sperl.org (CommuniGate Pro SMTP 6.1.2) with ESMTPSA id 6438099; Mon, 11 Apr 2016 13:29:17 +0000 From: kernel@martin.sperl.org To: Rob Herring , Mark Rutland , Stephen Warren , Lee Jones , Eric Anholt , Russell King , Vinod Koul , devicetree@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org Cc: Martin Sperl Subject: [PATCH V2 2/3] dmaengine: bcm2835: use platform_get_irq_byname Date: Mon, 11 Apr 2016 13:29:08 +0000 Message-Id: <1460381349-14408-3-git-send-email-kernel@martin.sperl.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1460381349-14408-1-git-send-email-kernel@martin.sperl.org> References: <1460381349-14408-1-git-send-email-kernel@martin.sperl.org> Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, 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 From: Martin Sperl Use platform_get_irq_byname to allow for correct mapping of interrupts to dma channels. The currently implemented device tree is unfortunately implemented with the wrong assumption, that each dma-channel has its own dma channel, but dma-irq 11 is handling dma-channel 11-14 and dma-irq 12 is actually a "catch all" interrupt. So here we use the byname variant and require that interrupts are explicitly named via the interrupts-name property in the device tree. The use of shared interrupts is also implemented. As a side-effect this means we can now use dma channels 12, 13 and 14 in a correct manner - also testing shows that onl using channels 11 to 14 for spi and i2s works perfectly (when playing some video) Signed-off-by: Martin Sperl Acked-by: Eric Anholt Acked-by: Mark Rutland --- drivers/dma/bcm2835-dma.c | 77 ++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 63 insertions(+), 14 deletions(-) diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index cc771cd..9740151 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -46,6 +46,9 @@ #include "virt-dma.h" +#define BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED 14 +#define BCM2835_DMA_CHAN_NAME_SIZE 8 + struct bcm2835_dmadev { struct dma_device ddev; spinlock_t lock; @@ -81,6 +84,7 @@ struct bcm2835_chan { void __iomem *chan_base; int irq_number; + unsigned int irq_flags; bool is_lite_channel; }; @@ -466,6 +470,15 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data) struct bcm2835_desc *d; unsigned long flags; + /* check the shared interrupt */ + if (c->irq_flags & IRQF_SHARED) { + /* check if the interrupt is enabled */ + flags = readl(c->chan_base + BCM2835_DMA_CS); + /* if not set then we are not the reason for the irq */ + if (!(flags & BCM2835_DMA_INT)) + return IRQ_NONE; + } + spin_lock_irqsave(&c->vc.lock, flags); /* Acknowledge interrupt */ @@ -506,8 +519,8 @@ static int bcm2835_dma_alloc_chan_resources(struct dma_chan *chan) return -ENOMEM; } - return request_irq(c->irq_number, - bcm2835_dma_callback, 0, "DMA IRQ", c); + return request_irq(c->irq_number, bcm2835_dma_callback, + c->irq_flags, "DMA IRQ", c); } static void bcm2835_dma_free_chan_resources(struct dma_chan *chan) @@ -819,7 +832,8 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan) return 0; } -static int bcm2835_dma_chan_init(struct bcm2835_dmadev *d, int chan_id, int irq) +static int bcm2835_dma_chan_init(struct bcm2835_dmadev *d, int chan_id, + int irq, unsigned int irq_flags) { struct bcm2835_chan *c; @@ -834,6 +848,7 @@ static int bcm2835_dma_chan_init(struct bcm2835_dmadev *d, int chan_id, int irq) c->chan_base = BCM2835_DMA_CHANIO(d->base, chan_id); c->ch = chan_id; c->irq_number = irq; + c->irq_flags = irq_flags; /* check in DEBUG register if this is a LITE channel */ if (readl(c->chan_base + BCM2835_DMA_DEBUG) & @@ -882,9 +897,11 @@ static int bcm2835_dma_probe(struct platform_device *pdev) struct resource *res; void __iomem *base; int rc; - int i; - int irq; + int i, j; + int irq[BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED + 1]; + int irq_flags; uint32_t chans_available; + char chan_name[BCM2835_DMA_CHAN_NAME_SIZE]; if (!pdev->dev.dma_mask) pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; @@ -941,16 +958,48 @@ static int bcm2835_dma_probe(struct platform_device *pdev) goto err_no_dma; } - for (i = 0; i < pdev->num_resources; i++) { - irq = platform_get_irq(pdev, i); - if (irq < 0) - break; - - if (chans_available & (1 << i)) { - rc = bcm2835_dma_chan_init(od, i, irq); - if (rc) - goto err_no_dma; + /* get irqs for each channel that we support */ + for (i = 0; i <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; i++) { + /* skip masked out channels */ + if (!(chans_available & (1 << i))) { + irq[i] = -1; + continue; } + + /* get the named irq */ + snprintf(chan_name, sizeof(chan_name), "dma%i", i); + irq[i] = platform_get_irq_byname(pdev, chan_name); + if (irq[i] >= 0) + continue; + + /* legacy device tree case handling */ + dev_warn_once(&pdev->dev, + "missing interrupts-names property in device tree - legacy interpretation is used"); + /* + * in case of channel >= 11 + * use the 11th interrupt and that is shared + */ + irq[i] = platform_get_irq(pdev, i < 11 ? i : 11); + } + + /* get irqs for each channel */ + for (i = 0; i <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; i++) { + /* skip channels without irq */ + if (irq[i] < 0) + continue; + + /* check if there are other channels that also use this irq */ + irq_flags = 0; + for (j = 0; j <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; j++) + if ((i != j) && (irq[j] == irq[i])) { + irq_flags = IRQF_SHARED; + break; + } + + /* initialize the channel */ + rc = bcm2835_dma_chan_init(od, i, irq[i], irq_flags); + if (rc) + goto err_no_dma; } dev_dbg(&pdev->dev, "Initialized %i DMA channels\n", i);