Internal SRAM configuration register 1.
| INTERNAL_SRAM_ICACHE_USAGE | Set 1 to someone bit means corresponding internal SRAM level can be accessed by icache. |
| INTERNAL_SRAM_DCACHE_USAGE | Set 1 to someone bit means corresponding internal SRAM level can be accessed by dcache. |
| INTERNAL_SRAM_CPU_USAGE | Set 1 to someone bit means corresponding internal SRAM level can be accessed by cpu. |