dma: add support for standard DMA access to SPU memory

* Mark SPU memory as sleep-blocking.
* Perform 4-byte accesses only in dma_memset() and dma_memcpy() (32-byte
  accesses freeze as one would expect).

This change does *NOT* implement support for SPU's integrated DMAC.

src/dma/dma.c

@@ -116,6 +116,11 @@ static int dma_setup(int channel, dma_size_t size, uint blocks,
 	if(ch->DAR >= 0xe5007000 && ch->DAR <= 0xe5204000)
 		dma_sleep_blocking[channel] = true;
 
+	if(ch->SAR >= 0xfe200000 && ch->SAR <= 0xfe3fffff)
+		dma_sleep_blocking[channel] = true;
+	if(ch->DAR >= 0xfe200000 && ch->DAR <= 0xfe3fffff)
+		dma_sleep_blocking[channel] = true;
+
 	return 0;
 }
 

src/dma/memcpy.c

@@ -4,6 +4,18 @@
 void *dma_memcpy(void * __restrict dst, const void * __restrict src,
 	size_t size)
 {
-	dma_transfer_sync(1, DMA_32B, size >> 5, src, DMA_INC, dst, DMA_INC);
+	int block_size = DMA_32B;
+	int block_count = size >> 5;
+
+	/* Use 4-byte transfers to access SPU memory */
+	if(((uint32_t)src >= 0xfe200000 && (uint32_t)src < 0xfe400000) ||
+	   ((uint32_t)dst >= 0xfe200000 && (uint32_t)dst < 0xfe400000))
+	{
+		block_size = DMA_4B;
+		block_count = size >> 2;
+	}
+
+	dma_transfer_sync(1, block_size, block_count, src, DMA_INC, dst,
+		DMA_INC);
 	return dst;
 }

src/dma/memset.c

@@ -14,6 +14,17 @@ void *dma_memset(void *dst, uint32_t l, size_t size)
 	   different memory regions, making the DMA faster than the CPU. */
 	for(int i = 0; i < 8; i++) ILbuf[i] = l;
 
-	dma_transfer_sync(1, DMA_32B, size>>5, ILbuf, DMA_FIXED, dst, DMA_INC);
+	int block_size = DMA_32B;
+	int block_count = size >> 5;
+
+	/* Use 4-byte transfers to access SPU memory */
+	if((uint32_t)dst >= 0xfe200000 && (uint32_t)dst < 0xfe400000)
+	{
+		block_size = DMA_4B;
+		block_count = size >> 2;
+	}
+
+	dma_transfer_sync(1, block_size, block_count, ILbuf, DMA_FIXED, dst,
+		DMA_INC);
 	return dst;
 }