MAX_DMA32_PFN      96 arch/mips/include/asm/dma.h #define MAX_DMA32_PFN		(1UL << (32 - PAGE_SHIFT))
MAX_DMA32_PFN      78 arch/mips/include/asm/mach-cavium-octeon/cpu-feature-overrides.h #define MAX_DMA32_PFN (((1ULL << 32) - (1ULL << 28)) >> PAGE_SHIFT)
MAX_DMA32_PFN      77 arch/x86/include/asm/dma.h #define MAX_DMA32_PFN (1UL << (32 - PAGE_SHIFT))