MIPS: Allow MAX_DMA32_PFN to be overridden.

Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

kernel os linux

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>

authored by

David Daney and committed by

Ralf Baechle 15 years ago cfd57099 f1299072

1 changed file

expand all

arch

mips

include

asm

dma.h

arch/mips/include/asm/dma.h

··· 91 91 #define MAX_DMA_ADDRESS (PAGE_OFFSET + 0x01000000) 92 92 #endif 93 93 #define MAX_DMA_PFN PFN_DOWN(virt_to_phys((void *)MAX_DMA_ADDRESS)) 94 + 95 + #ifndef MAX_DMA32_PFN 94 96 #define MAX_DMA32_PFN (1UL << (32 - PAGE_SHIFT)) 97 + #endif 95 98 96 99 /* 8237 DMA controllers */ 97 100 #define IO_DMA1_BASE 0x00 /* 8 bit slave DMA, channels 0..3 */