From patchwork Thu Jan 7 17:33:01 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 7978651 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 [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 516639F1CC for ; Thu, 7 Jan 2016 17:36:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5D7612012D for ; Thu, 7 Jan 2016 17:35:59 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 687E820109 for ; Thu, 7 Jan 2016 17:35:58 +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 1aHES5-0007XI-P0; Thu, 07 Jan 2016 17:34:21 +0000 Received: from 212-186-180-163.dynamic.surfer.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aHERT-0007Il-GK; Thu, 07 Jan 2016 17:33:46 +0000 Received: from raspcm.intern.sperl.org (account martin@sperl.org [10.10.10.41] verified) by sperl.org (CommuniGate Pro SMTP 6.1.2) with ESMTPSA id 6391114; Thu, 07 Jan 2016 17:33:14 +0000 From: kernel@martin.sperl.org To: Vinod Koul , Dan Williams , Stephen Warren , Lee Jones , Eric Anholt , dmaengine@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Matthias Reichl Subject: [PATCH V2 3/8] dmaengine: bcm2835: use shared interrupt for channel 11 to 14. Date: Thu, 7 Jan 2016 17:33:01 +0000 Message-Id: <1452187987-2605-4-git-send-email-kernel@martin.sperl.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1452187987-2605-1-git-send-email-kernel@martin.sperl.org> References: <1452187987-2605-1-git-send-email-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160107_093344_236117_6FE3690B X-CRM114-Status: GOOD ( 17.09 ) X-Spam-Score: -0.9 (/) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 The bcm2835 dma channel 11 to 14 only have a single shared irq line, so this patch implements shared interrupts for these channels. To avoid changes to the device tree (with regards to interrupts listed, which reflects on pdev->num_resources) a fixed channel count had to get used in the code instead. With this patch applied we now have 11 dma channels available to the ARM side of the SOC. Signed-off-by: Martin Sperl Reviewed-by: Eric Anholt --- drivers/dma/bcm2835-dma.c | 46 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 41 insertions(+), 5 deletions(-) diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index e4ca980..0c04236 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -81,7 +81,9 @@ struct bcm2835_chan { struct dma_pool *cb_pool; void __iomem *chan_base; + int irq_number; + unsigned long irq_flags; }; struct bcm2835_desc { @@ -127,6 +129,19 @@ struct bcm2835_desc { #define BCM2835_DMA_CHAN(n) ((n) << 8) /* Base address */ #define BCM2835_DMA_CHANIO(base, n) ((base) + BCM2835_DMA_CHAN(n)) +/* + * number of dma channels we support + * we do not support DMA channel 15, as it is in a separate IO range, + * does not have a separate IRQ line except for the "catch all IRQ line" + * finally this channel is used by the firmware so is not available + */ +#define BCM2835_DMA_MAX_CHANNEL_NUMBER 14 + +/* the DMA channels 11 to 14 share a common interrupt */ +#define BCM2835_DMA_IRQ_SHARED_MASK (BIT(11) | BIT(12) | BIT(13) | BIT(14)) +#define BCM2835_DMA_IRQ_SHARED 11 +#define BCM2835_DMA_IRQ_ALL 12 + static inline struct bcm2835_dmadev *to_bcm2835_dma_dev(struct dma_device *d) { return container_of(d, struct bcm2835_dmadev, ddev); @@ -215,6 +230,15 @@ 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 */ @@ -250,7 +274,8 @@ static int bcm2835_dma_alloc_chan_resources(struct dma_chan *chan) } return request_irq(c->irq_number, - bcm2835_dma_callback, 0, "DMA IRQ", c); + bcm2835_dma_callback, + c->irq_flags, "DMA IRQ", c); } static void bcm2835_dma_free_chan_resources(struct dma_chan *chan) @@ -526,7 +551,8 @@ 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 long irq_flags) { struct bcm2835_chan *c; @@ -541,6 +567,7 @@ 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; return 0; } @@ -586,6 +613,7 @@ static int bcm2835_dma_probe(struct platform_device *pdev) int rc; int i; int irq; + unsigned long irq_flags; uint32_t chans_available; if (!pdev->dev.dma_mask) @@ -638,13 +666,21 @@ 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); + for (i = 0; i <= BCM2835_DMA_MAX_CHANNEL_NUMBER; i++) { + if (BCM2835_DMA_IRQ_SHARED_MASK & BIT(i)) { + irq = platform_get_irq(pdev, + BCM2835_DMA_IRQ_SHARED); + irq_flags = IRQF_SHARED; + } else { + irq = platform_get_irq(pdev, i); + irq_flags = 0; + } + if (irq < 0) break; if (chans_available & (1 << i)) { - rc = bcm2835_dma_chan_init(od, i, irq); + rc = bcm2835_dma_chan_init(od, i, irq, irq_flags); if (rc) goto err_no_dma; }