| Message ID | 1460381349-14408-3-git-send-email-kernel@martin.sperl.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Apr 11, 2016 at 3:29 PM, <kernel@martin.sperl.org> wrote: > From: Martin Sperl <kernel@martin.sperl.org> > > 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 interrupt-names > device tree. > > The use of shared interrupts is also implemented. You're not explicitly looking for "dma-shared-all" for that? You might as well just declare a single unnamed interrupt in the bindings. > + /* legacy device tree case handling */ > + dev_warn_once(&pdev->dev, > + "missing interrupts-names property in device tree - legacy interpretation is used"); interrupt-names Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 20.04.2016 08:51, Geert Uytterhoeven wrote: > On Mon, Apr 11, 2016 at 3:29 PM, <kernel@martin.sperl.org> wrote: >> From: Martin Sperl <kernel@martin.sperl.org> >> >> 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 > > interrupt-names Vinod has just merged this patch - do you want me to submit another to correct those? > You're not explicitly looking for "dma-shared-all" for that? > You might as well just declare a single unnamed interrupt in the bindings. dma-shared-all is unfortunately an interrupt-line that triggers for interrupt-channels 0-15 and that includes the dma channels that are owned by the firmware. It is there mostly to document the interrupt-line (which is there in the existing device tree files - it is not used. Martin -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Martin, On Wed, Apr 20, 2016 at 1:06 PM, Martin Sperl <kernel@martin.sperl.org> wrote: > On 20.04.2016 08:51, Geert Uytterhoeven wrote: >> >> On Mon, Apr 11, 2016 at 3:29 PM, <kernel@martin.sperl.org> wrote: >>> >>> From: Martin Sperl <kernel@martin.sperl.org> >>> >>> 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 >> >> interrupt-names > > Vinod has just merged this patch - do you want me to submit another Yeah, that's how I noticed by accident :-) > to correct those? For the commit message it's indeed too late. For the error message in the code, yes please. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Apr 20, 2016 at 01:12:36PM +0200, Geert Uytterhoeven wrote: > Hi Martin, > > On Wed, Apr 20, 2016 at 1:06 PM, Martin Sperl <kernel@martin.sperl.org> wrote: > > On 20.04.2016 08:51, Geert Uytterhoeven wrote: > >> > >> On Mon, Apr 11, 2016 at 3:29 PM, <kernel@martin.sperl.org> wrote: > >>> > >>> From: Martin Sperl <kernel@martin.sperl.org> > >>> > >>> 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 > >> > >> interrupt-names well spotted > > > > Vinod has just merged this patch - do you want me to submit another > > Yeah, that's how I noticed by accident :-) > > > to correct those? > > For the commit message it's indeed too late. For the error message in the > code, yes please. I can drop the branch
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);