MIPS: Allow MAX_DMA32_PFN to be overridden.
DMA mapping may reduce the usable physical address range usable for
32-bit DMA.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Patchwork: http://patchwork.linux-mips.org/patch/1633/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/dma.h b/arch/mips/include/asm/dma.h
index 1353c81..2d47da6 100644
--- a/arch/mips/include/asm/dma.h
+++ b/arch/mips/include/asm/dma.h
@@ -91,7 +91,10 @@
#define MAX_DMA_ADDRESS (PAGE_OFFSET + 0x01000000)
#endif
#define MAX_DMA_PFN PFN_DOWN(virt_to_phys((void *)MAX_DMA_ADDRESS))
+
+#ifndef MAX_DMA32_PFN
#define MAX_DMA32_PFN (1UL << (32 - PAGE_SHIFT))
+#endif
/* 8237 DMA controllers */
#define IO_DMA1_BASE 0x00 /* 8 bit slave DMA, channels 0..3 */