dmaengine: omap-dma: move IRQ handling to omap-dma
authorRussell King <rmk+kernel@arm.linux.org.uk>
Tue, 10 Dec 2013 19:05:50 +0000 (19:05 +0000)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Thu, 3 Apr 2014 23:31:53 +0000 (00:31 +0100)
Move the interrupt handling for OMAP2+ into omap-dma, rather than using
the legacy support in the platform code.

Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
drivers/dma/omap-dma.c

index 00f8e56..ec98e71 100644 (file)
@@ -30,6 +30,10 @@ struct omap_dmadev {
        void __iomem *base;
        const struct omap_dma_reg *reg_map;
        struct omap_system_dma_plat_info *plat;
+       bool legacy;
+       spinlock_t irq_lock;
+       uint32_t irq_enable_mask;
+       struct omap_chan *lch_map[32];
 };
 
 struct omap_chan {
@@ -254,10 +258,22 @@ static void omap_dma_clear_csr(struct omap_chan *c)
                omap_dma_chan_write(c, CSR, ~0);
 }
 
+static unsigned omap_dma_get_csr(struct omap_chan *c)
+{
+       unsigned val = omap_dma_chan_read(c, CSR);
+
+       if (!dma_omap1())
+               omap_dma_chan_write(c, CSR, val);
+
+       return val;
+}
+
 static void omap_dma_assign(struct omap_dmadev *od, struct omap_chan *c,
        unsigned lch)
 {
        c->channel_base = od->base + od->plat->channel_stride * lch;
+
+       od->lch_map[lch] = c;
 }
 
 static void omap_dma_start(struct omap_chan *c, struct omap_desc *d)
@@ -460,32 +476,103 @@ static void omap_dma_sched(unsigned long data)
        }
 }
 
+static irqreturn_t omap_dma_irq(int irq, void *devid)
+{
+       struct omap_dmadev *od = devid;
+       unsigned status, channel;
+
+       spin_lock(&od->irq_lock);
+
+       status = omap_dma_glbl_read(od, IRQSTATUS_L1);
+       status &= od->irq_enable_mask;
+       if (status == 0) {
+               spin_unlock(&od->irq_lock);
+               return IRQ_NONE;
+       }
+
+       while ((channel = ffs(status)) != 0) {
+               unsigned mask, csr;
+               struct omap_chan *c;
+
+               channel -= 1;
+               mask = BIT(channel);
+               status &= ~mask;
+
+               c = od->lch_map[channel];
+               if (c == NULL) {
+                       /* This should never happen */
+                       dev_err(od->ddev.dev, "invalid channel %u\n", channel);
+                       continue;
+               }
+
+               csr = omap_dma_get_csr(c);
+               omap_dma_glbl_write(od, IRQSTATUS_L1, mask);
+
+               omap_dma_callback(channel, csr, c);
+       }
+
+       spin_unlock(&od->irq_lock);
+
+       return IRQ_HANDLED;
+}
+
 static int omap_dma_alloc_chan_resources(struct dma_chan *chan)
 {
        struct omap_dmadev *od = to_omap_dma_dev(chan->device);
        struct omap_chan *c = to_omap_dma_chan(chan);
        int ret;
 
-       dev_dbg(od->ddev.dev, "allocating channel for %u\n", c->dma_sig);
+       if (od->legacy) {
+               ret = omap_request_dma(c->dma_sig, "DMA engine",
+                                      omap_dma_callback, c, &c->dma_ch);
+       } else {
+               ret = omap_request_dma(c->dma_sig, "DMA engine", NULL, NULL,
+                                      &c->dma_ch);
+       }
 
-       ret = omap_request_dma(c->dma_sig, "DMA engine", omap_dma_callback,
-                              c, &c->dma_ch);
+       dev_dbg(od->ddev.dev, "allocating channel %u for %u\n",
+               c->dma_ch, c->dma_sig);
 
-       if (ret >= 0)
+       if (ret >= 0) {
                omap_dma_assign(od, c, c->dma_ch);
 
+               if (!od->legacy) {
+                       unsigned val;
+
+                       spin_lock_irq(&od->irq_lock);
+                       val = BIT(c->dma_ch);
+                       omap_dma_glbl_write(od, IRQSTATUS_L1, val);
+                       od->irq_enable_mask |= val;
+                       omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
+
+                       val = omap_dma_glbl_read(od, IRQENABLE_L0);
+                       val &= ~BIT(c->dma_ch);
+                       omap_dma_glbl_write(od, IRQENABLE_L0, val);
+                       spin_unlock_irq(&od->irq_lock);
+               }
+       }
+
        return ret;
 }
 
 static void omap_dma_free_chan_resources(struct dma_chan *chan)
 {
+       struct omap_dmadev *od = to_omap_dma_dev(chan->device);
        struct omap_chan *c = to_omap_dma_chan(chan);
 
+       if (!od->legacy) {
+               spin_lock_irq(&od->irq_lock);
+               od->irq_enable_mask &= ~BIT(c->dma_ch);
+               omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
+               spin_unlock_irq(&od->irq_lock);
+       }
+
        c->channel_base = NULL;
+       od->lch_map[c->dma_ch] = NULL;
        vchan_free_chan_resources(&c->vc);
        omap_free_dma(c->dma_ch);
 
-       dev_dbg(c->vc.chan.device->dev, "freeing channel for %u\n", c->dma_sig);
+       dev_dbg(od->ddev.dev, "freeing channel for %u\n", c->dma_sig);
 }
 
 static size_t omap_dma_sg_size(struct omap_sg *sg)
@@ -1015,7 +1102,7 @@ static int omap_dma_probe(struct platform_device *pdev)
 {
        struct omap_dmadev *od;
        struct resource *res;
-       int rc, i;
+       int rc, i, irq;
 
        od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
        if (!od)
@@ -1045,6 +1132,7 @@ static int omap_dma_probe(struct platform_device *pdev)
        INIT_LIST_HEAD(&od->ddev.channels);
        INIT_LIST_HEAD(&od->pending);
        spin_lock_init(&od->lock);
+       spin_lock_init(&od->irq_lock);
 
        tasklet_init(&od->task, omap_dma_sched, (unsigned long)od);
 
@@ -1056,6 +1144,21 @@ static int omap_dma_probe(struct platform_device *pdev)
                }
        }
 
+       irq = platform_get_irq(pdev, 1);
+       if (irq <= 0) {
+               dev_info(&pdev->dev, "failed to get L1 IRQ: %d\n", irq);
+               od->legacy = true;
+       } else {
+               /* Disable all interrupts */
+               od->irq_enable_mask = 0;
+               omap_dma_glbl_write(od, IRQENABLE_L1, 0);
+
+               rc = devm_request_irq(&pdev->dev, irq, omap_dma_irq,
+                                     IRQF_SHARED, "omap-dma-engine", od);
+               if (rc)
+                       return rc;
+       }
+
        rc = dma_async_device_register(&od->ddev);
        if (rc) {
                pr_warn("OMAP-DMA: failed to register slave DMA engine device: %d\n",
@@ -1092,6 +1195,12 @@ static int omap_dma_remove(struct platform_device *pdev)
                of_dma_controller_free(pdev->dev.of_node);
 
        dma_async_device_unregister(&od->ddev);
+
+       if (!od->legacy) {
+               /* Disable all interrupts */
+               omap_dma_glbl_write(od, IRQENABLE_L0, 0);
+       }
+
        omap_dma_free(od);
 
        return 0;