AW: sh: sh7723/7724 nmi: nmi stops DMA transfers

Commit Message

Szafranek, Michael Dec. 14, 2010, 9:15 a.m. UTC

None

Patch

diff --git a/arch/sh/drivers/dma/dma-sh.c b/arch/sh/drivers/dma/dma-sh.c index 8272087..5a1c6f9 100644
--- a/arch/sh/drivers/dma/dma-sh.c
+++ b/arch/sh/drivers/dma/dma-sh.c
@@ -276,6 +276,26 @@  static struct dma_info sh_dmac_info = {
        .flags          = DMAC_CHANNELS_TEI_CAPABLE,
 };

+#if defined(CONFIG_CPU_SUBTYPE_SH7723) ||
+defined(CONFIG_CPU_SUBTYPE_SH7724)
+int sh_dma_notifier(struct notifier_block *nb, unsigned long val, void
+*args) {
+       if (!in_nmi())
+               return NOTIFY_DONE;
+
+       /* every NMI usually stops all active DMA transfers. */
+       /* Reset DMA channels so that the transfers are resumed */
+       dmaor_reset(0);
+       dmaor_reset(1);
+
+       return NOTIFY_OK;
+}
+
+static struct notifier_block sh_dma_nb = {
+       .notifier_call  = sh_dma_notifier,
+       .priority       = 0,
+};
+#endif
+
 #ifdef CONFIG_CPU_SH4
 static unsigned int get_dma_error_irq(int n)  { @@ -330,6 +350,12 @@ static int __init sh_dmac_init(void)
                return i;
 #endif

+#if defined(CONFIG_CPU_SUBTYPE_SH7723) || defined(CONFIG_CPU_SUBTYPE_SH7724)
+       i = register_die_notifier(&sh_dma_nb);
+       if (unlikely(i != 0))
+               return i;
+#endif
+
        return register_dmac(info);
 }

@@ -338,6 +364,10 @@  static void __exit sh_dmac_exit(void)  #ifdef CONFIG_CPU_SH4
        int n;

+#if defined(CONFIG_CPU_SUBTYPE_SH7723) || defined(CONFIG_CPU_SUBTYPE_SH7724)
+       unregister_die_notifier(&sh_dma_nb);
+#endif
+
        for (n = 0; n < NR_DMAE; n++) {
                free_irq(get_dma_error_irq(n), (void *)dmae_name[n]);
        }
diff --git a/drivers/dma/shdma.c b/drivers/dma/shdma.c index eb6b54d..76dd70b 100644
--- a/drivers/dma/shdma.c
+++ b/drivers/dma/shdma.c
@@ -849,6 +849,22 @@  static irqreturn_t sh_dmae_err(int irq, void *data)  }  #endif

+#if defined(CONFIG_CPU_SUBTYPE_SH7723) ||
+defined(CONFIG_CPU_SUBTYPE_SH7724)
+int dmae_notifier_call(struct notifier_block *nb, unsigned long val,
+void *args) {
+       struct sh_dmae_device *shdev = container_of(nb, struct sh_dmae_device,
+nb);
+
+       if (!in_nmi())
+               return NOTIFY_DONE;
+
+       /* every NMI usually stops all active DMA transfers. */
+       /* Reset DMA channels so that the transfers are resumed */
+       sh_dmae_rst(shdev);
+
+       return NOTIFY_OK;
+}
+#endif
+
 static void dmae_do_tasklet(unsigned long data)  {
        struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data; @@ -1085,6 +1101,18 @@ static int __init sh_dmae_probe(struct platform_device *pdev)
        chanirq_res = errirq_res;
 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */

+
+#if defined(CONFIG_CPU_SUBTYPE_SH7723) || defined(CONFIG_CPU_SUBTYPE_SH7724)
+       shdev->nb.notifier_call = dmae_notifier_call;
+       shdev->nb.priority      = 0;
+
+       err = register_die_notifier(&shdev->nb);
+       if (err) {
+               dev_err(&pdev->dev, "Registering NMI notifier failed\n");
+               goto eirqres;
+       }
+#endif
+
        if (chanirq_res->start == chanirq_res->end &&
            !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
                /* Special case - all multiplexed */
@@ -1157,6 +1185,10 @@  static int __exit sh_dmae_remove(struct platform_device *pdev)
        struct resource *res;
        int errirq = platform_get_irq(pdev, 0);

+#if defined(CONFIG_CPU_SUBTYPE_SH7723) || defined(CONFIG_CPU_SUBTYPE_SH7724)
+       unregister_die_notifier(&shdev->nb);
+#endif
+
        dma_async_device_unregister(&shdev->common);

        if (errirq > 0)
diff --git a/drivers/dma/shdma.h b/drivers/dma/shdma.h index 4021275..2a01754 100644
--- a/drivers/dma/shdma.h
+++ b/drivers/dma/shdma.h
@@ -43,6 +43,9 @@  struct sh_dmae_device {
        struct dma_device common;
        struct sh_dmae_chan *chan[SH_DMAC_MAX_CHANNELS];
        struct sh_dmae_pdata *pdata;
+#if defined(CONFIG_CPU_SUBTYPE_SH7723) || defined(CONFIG_CPU_SUBTYPE_SH7724)
+       struct notifier_block nb;
+#endif
        u32 __iomem *chan_reg;
        u16 __iomem *dmars;
 };