Switch DMA wait loop to idle CPU

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@11914 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 20 insertions, 11 deletions

diff --git a/firmware/target/arm/gigabeat/meg-fx/ata-meg-fx.c b/firmware/target/arm/gigabeat/meg-fx/ata-meg-fx.c
index de4626e288..361b9d4b6f 100644
--- a/firmware/target/arm/gigabeat/meg-fx/ata-meg-fx.c
+++ b/firmware/target/arm/gigabeat/meg-fx/ata-meg-fx.c
@@ -57,14 +57,15 @@ void copy_read_sectors(unsigned char* buf, int wordcount)
     /* This should never happen, but worth watching for */
     if(wordcount > (1 << 18))
         panicf("atd-meg-fx.c: copy_read_sectors: too many sectors per read!");
-#undef GIGABEAT_DEBUG_ATA
+
+//#define GIGABEAT_DEBUG_ATA
 #ifdef GIGABEAT_DEBUG_ATA
-    static int line = 0;
-    static char str[256];
-    snprintf(str, sizeof(str), "DMA to %08x, %d", buf, wordcount);
-    lcd_puts(16, line, str);
-    line = (line+1) % 32;
-    lcd_update();
+                static int line = 0;
+                static char str[256];
+                snprintf(str, sizeof(str), "ODD DMA to %08x, %d", buf, wordcount);
+                lcd_puts(10, line, str);
+                line = (line+1) % 32;
+                lcd_update();
 #endif
     /* Reset the channel */
     DMASKTRIG0 |= 4;
@@ -81,20 +82,26 @@ void copy_read_sectors(unsigned char* buf, int wordcount)
     DIDSTC0 = 0;
 
     /* DACK/DREQ Sync to AHB, Int on Transfer complete, Whole service, No reload, 16-bit transfers */
-    DCON0 = ((1 << 30) | (1<<27) | (1<<22) | (1<<20)) | wordcount;
+    DCON0 = ((1 << 30) | (1<< 29) | (1<<27) | (1<<22) | (1<<20)) | wordcount;
 
     /* Activate the channel */
     DMASKTRIG0 = 0x2;
 
-    /* Dump cache for the buffer  */
-    dump_dcache_range((void *)buf, wordcount*2);
+        invalidate_dcache_range((void *)buf, wordcount*2);
 
+        INTMSK &= ~(1<<17);      /* unmask the interrupt */
+        SRCPND = (1<<17);       /* clear any pending interrupts */
     /* Start DMA */
     DMASKTRIG0 |= 0x1;
 
     /* Wait for transfer to complete */
     while((DSTAT0 & 0x000fffff))
-        yield();
+                CLKCON |= (1 << 2); /* set IDLE bit */
+        /* Dump cache for the buffer  */
+}
+
+void dma0(void)
+{
 }
 
 
diff --git a/firmware/target/arm/gigabeat/meg-fx/system-meg-fx.c b/firmware/target/arm/gigabeat/meg-fx/system-meg-fx.c
index b8bcda3c95..b2b4a6207b 100644
--- a/firmware/target/arm/gigabeat/meg-fx/system-meg-fx.c
+++ b/firmware/target/arm/gigabeat/meg-fx/system-meg-fx.c
@@ -33,6 +33,8 @@ void irq(void)
     /* Timer 4 */
     if ((intpending & TIMER4_MASK) != 0)
         timer4();
+        else if ((intpending & DMA0_MASK) != 0)
+                dma0();
     else
     {
         /* unexpected interrupt */