ARM: OMAP: Fix race in OMAP2/3 DMA IRQ handling

[linux-2.6-omap-h63xx.git] / arch / arm / plat-omap / dma.c

diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 50f8b4ad9a0942a0e818a746dff055d17b8be139..bec8e363d545fae4fb9bf1dbfa1d33942b702d73 100644 (file)
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -29,7 +29,7 @@
 
 #include <asm/system.h>
 #include <mach/hardware.h>
-#include <asm/dma.h>
+#include <mach/dma.h>
 
 #include <mach/tc.h>
 
@@ -278,14 +278,11 @@ void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
                u32 val;
 
                val = dma_read(CCR(lch));
-               val &= ~(3 << 19);
-               if (dma_trigger > 63)
-                       val |= 1 << 20;
-               if (dma_trigger > 31)
-                       val |= 1 << 19;
 
-               val &= ~(0x1f);
-               val |= (dma_trigger & 0x1f);
+               /* DMA_SYNCHRO_CONTROL_UPPER depends on the channel number */
+               val &= ~((3 << 19) | 0x1f);
+               val |= (dma_trigger & ~0x1f) << 14;
+               val |= dma_trigger & 0x1f;
 
                if (sync_mode & OMAP_DMA_SYNC_FRAME)
                        val |= 1 << 5;
@@ -1848,9 +1845,22 @@ static int omap2_dma_handle_ch(int ch)
                printk(KERN_INFO
                       "DMA synchronization event drop occurred with device "
                       "%d\n", dma_chan[ch].dev_id);
-       if (unlikely(status & OMAP2_DMA_TRANS_ERR_IRQ))
+       if (unlikely(status & OMAP2_DMA_TRANS_ERR_IRQ)) {
                printk(KERN_INFO "DMA transaction error with device %d\n",
                       dma_chan[ch].dev_id);
+               if (cpu_class_is_omap2()) {
+                       /* Errata: sDMA Channel is not disabled
+                        * after a transaction error. So we explicitely
+                        * disable the channel
+                        */
+                       u32 ccr;
+
+                       ccr = dma_read(CCR(ch));
+                       ccr &= ~OMAP_DMA_CCR_EN;
+                       dma_write(ccr, CCR(ch));
+                       dma_chan[ch].flags &= ~OMAP_DMA_ACTIVE;
+               }
+       }
        if (unlikely(status & OMAP2_DMA_SECURE_ERR_IRQ))
                printk(KERN_INFO "DMA secure error with device %d\n",
                       dma_chan[ch].dev_id);
@@ -1878,11 +1888,11 @@ static int omap2_dma_handle_ch(int ch)
                status = dma_read(CSR(ch));
        }
 
+       dma_write(status, CSR(ch));
+
        if (likely(dma_chan[ch].callback != NULL))
                dma_chan[ch].callback(ch, status, dma_chan[ch].data);
 
-       dma_write(status, CSR(ch));
-
        return 0;
 }