dmaengine: ti: omap-dma: Use cpu notifier to block idle for omap2

For omap2, we need to block idle if SDMA is busy. Let's do this with a
cpu notifier and remove the custom call.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Vinod Koul <vkoul@kernel.org>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c
index 1581b6a6a416c9ddd477376ab279f2956b017bd8..6953c47d8dc6816042999650ec0d53c7a792d4ee 100644 (file)
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -83,8 +83,6 @@ static int omap2_enter_full_retention(void)
        l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
        omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 
-       cpu_cluster_pm_enter();
-
        /* One last check for pending IRQs to avoid extra latency due
         * to sleeping unnecessarily. */
        if (omap_irq_pending())
@@ -96,8 +94,6 @@ static int omap2_enter_full_retention(void)
                           OMAP_SDRC_REGADDR(SDRC_POWER));
 
 no_sleep:
-       cpu_cluster_pm_exit();
-
        clk_enable(osc_ck);
 
        /* clear CORE wake-up events */
@@ -162,25 +158,27 @@ static int omap2_can_sleep(void)
                return 0;
        if (__clk_is_enabled(osc_ck))
                return 0;
-       if (omap_dma_running())
-               return 0;
 
        return 1;
 }
 
 static void omap2_pm_idle(void)
 {
-       if (!omap2_can_sleep()) {
-               if (omap_irq_pending())
-                       return;
-               omap2_enter_mpu_retention();
-               return;
-       }
+       int error;
 
        if (omap_irq_pending())
                return;
 
+       error = cpu_cluster_pm_enter();
+       if (error || !omap2_can_sleep()) {
+               omap2_enter_mpu_retention();
+               goto out_cpu_cluster_pm;
+       }
+
        omap2_enter_full_retention();
+
+out_cpu_cluster_pm:
+       cpu_cluster_pm_exit();
 }
 
 static void __init prcm_setup_regs(void)

diff --git a/drivers/dma/ti/omap-dma.c b/drivers/dma/ti/omap-dma.c
index 9c5f17a48d460df57581e73ded19d4318d740912..fc8f7b2fc7b331d907e27d27deffa2e0dd45ba78 100644 (file)
--- a/drivers/dma/ti/omap-dma.c
+++ b/drivers/dma/ti/omap-dma.c
@@ -27,6 +27,7 @@
 struct omap_dma_config {
        int lch_end;
        unsigned int rw_priority:1;
+       unsigned int needs_busy_check:1;
        unsigned int may_lose_context:1;
        unsigned int needs_lch_clear:1;
 };
@@ -1521,6 +1522,38 @@ static void omap_dma_free(struct omap_dmadev *od)
        }
 }
 
+/* Currently only used for omap2. For omap1, also a check for lcd_dma is needed */
+static int omap_dma_busy_notifier(struct notifier_block *nb,
+                                 unsigned long cmd, void *v)
+{
+       struct omap_dmadev *od;
+       struct omap_chan *c;
+       int lch = -1;
+
+       od = container_of(nb, struct omap_dmadev, nb);
+
+       switch (cmd) {
+       case CPU_CLUSTER_PM_ENTER:
+               while (1) {
+                       lch = find_next_bit(od->lch_bitmap, od->lch_count,
+                                           lch + 1);
+                       if (lch >= od->lch_count)
+                               break;
+                       c = od->lch_map[lch];
+                       if (!c)
+                               continue;
+                       if (omap_dma_chan_read(c, CCR) & CCR_ENABLE)
+                               return NOTIFY_BAD;
+               }
+               break;
+       case CPU_CLUSTER_PM_ENTER_FAILED:
+       case CPU_CLUSTER_PM_EXIT:
+               break;
+       }
+
+       return NOTIFY_OK;
+}
+
 /*
  * We are using IRQENABLE_L1, and legacy DMA code was using IRQENABLE_L0.
  * As the DSP may be using IRQENABLE_L2 and L3, let's not touch those for
@@ -1778,7 +1811,10 @@ static int omap_dma_probe(struct platform_device *pdev)
 
        omap_dma_init_gcr(od, DMA_DEFAULT_ARB_RATE, DMA_DEFAULT_FIFO_DEPTH, 0);
 
-       if (od->cfg->may_lose_context) {
+       if (od->cfg->needs_busy_check) {
+               od->nb.notifier_call = omap_dma_busy_notifier;
+               cpu_pm_register_notifier(&od->nb);
+       } else if (od->cfg->may_lose_context) {
                od->nb.notifier_call = omap_dma_context_notifier;
                cpu_pm_register_notifier(&od->nb);
        }
@@ -1822,6 +1858,7 @@ static const struct omap_dma_config omap2420_data = {
        .lch_end = CCFN,
        .rw_priority = true,
        .needs_lch_clear = true,
+       .needs_busy_check = true,
 };
 
 static const struct omap_dma_config omap2430_data = {