mips物理内存空间分布
#ifdef CONFIG_BRCM_HAS_1GB_MEMC0
/*
* Physical address map for <= 1GB MEMC0*
* 0000_0000 - 0fff_ffff: MEMC0 (256MB)
* 1000_0000 - 1fff_ffff: EBI/Registers (256MB)
* 2000_0000 - 4fff_ffff: MEMC0 (768MB)
* 6000_0000 - 7fff_ffff: MEMC1 (512MB)
* a000_0000 - bfff_ffff: PCIe MEM BARs (512MB)
* d000_0000 - efff_ffff: PCI2.3 MEM BARs (512MB)
* f000_0000 - f05f_ffff: PCI2.3 IO BARs (6MB)
* f000_0000 - f060_000b: PCI2.3 Configuration access (12B)
* f100_0000 - f100_001f: PCIe Configuration access - 7420 only (32B)
*
* PCI2.3/PCIe inbound BAR:
*
* 0000_0000 - 0fff_ffff: MEMC0 (256MB @ 0000_0000)
* 1000_0000 - 3fff_ffff: MEMC0 (768MB @ 2000_0000)
* 4000_0000 - 7fff_ffff: MEMC1 (1024MB @ 6000_0000) (not currently implemented)
*/
#else
/*
* Physical address map for 2GB MEMC0
*
* 0000_0000 - 0fff_ffff: MEMC0 (256MB)
* 1000_0000 - 1fff_ffff: EBI/Registers (256MB)
* 2000_0000 - 8fff_ffff: MEMC0 (1792MB)
* 9000_0000 - cfff_ffff: MEMC1 (1024MB)
* d000_0000 - efff_ffff: PCIe MEM BARs (512MB)
*
* PCIe inbound BAR:
*
* 0000_0000 - 0fff_ffff: MEMC0 (256MB @ 0000_0000)
* 1000_0000 - 7fff_ffff: MEMC0 (1792MB @ 2000_0000)
* 8000_0000 - bfff_ffff: MEMC1 (1024MB @ 9000_0000)
*/
#endif
对于MEMC0支持1G还是2G，完全由架构决定；
上述定义可以参考arch/mips/asm/include/spaces.h文件。