mmu.c
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上传日期:2022-08-05
资源大小:793k
文件大小:4k
源码类别:
微处理器开发
开发平台:
Unix_Linux
- /************************************************
- NAME : MMU.C
- DESC :
- Revision: 2002.2.28 ver 0.0
- ************************************************/
- #include "def.h"
- #include "option.h"
- #include "2410addr.h"
- #include "2410lib.h"
- #include "2410slib.h"
- #include "mmu.h"
- // 1) Only the section table is used.
- // 2) The cachable/non-cachable area can be changed by MMT_DEFAULT value.
- // The section size is 1MB.
- void MMU_Init(void)
- {
- int i,j;
- //========================== IMPORTANT NOTE =========================
- //The current stack and code area can't be re-mapped in this routine.
- //If you want memory map mapped freely, your own sophiscated MMU
- //initialization code is needed.
- //===================================================================
- MMU_DisableDCache();
- MMU_DisableICache();
- //If write-back is used,the DCache should be cleared.
- for(i=0;i<64;i++)
- for(j=0;j<8;j++)
- MMU_CleanInvalidateDCacheIndex((i<<26)|(j<<5));
- MMU_InvalidateICache();
- #if 0
- //To complete MMU_Init() fast, Icache may be turned on here.
- MMU_EnableICache();
- #endif
- MMU_DisableMMU();
- MMU_InvalidateTLB();
- //MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr)
- // MMU_SetMTT(0x00000000,0x07f00000,0x00000000,RW_NCNB); //bank0
- MMU_SetMTT(0x00000000,0x00400000,0x30100000,RW_CB); //bank0 when no nor flash, must do this
- MMU_SetMTT(0x08000000,0x0ff00000,0x08000000,RW_NCNB); //bank1
- MMU_SetMTT(0x10000000,0x17f00000,0x10000000,RW_NCNB); //bank2
- MMU_SetMTT(0x18000000,0x1ff00000,0x18000000,RW_NCNB); //bank3
- MMU_SetMTT(0x20000000,0x27f00000,0x20000000,RW_NCNB); //bank4
- MMU_SetMTT(0x28000000,0x2ff00000,0x28000000,RW_NCNB); //bank5
- MMU_SetMTT(0x30000000,0x30100000,0x30000000,RW_CB); //bank6-1
- // MMU_SetMTT(0x30200000,0x33e00000,0x30200000,(AP_RO|DOMAIN0|NCNB|DESC_SEC)); //bank6-2 原来的
- MMU_SetMTT(0x31000000,0x33e00000,0x31000000,RW_CB); //bank6-2 龚俊修改的
- MMU_SetMTT(0x33f00000,0x33f00000,0x33f00000,RW_CB); //bank6-3 原来的
- MMU_SetMTT(0x38000000,0x3ff00000,0x38000000,RW_NCNB); //bank7
- MMU_SetMTT(0x40000000,0x47f00000,0x40000000,RW_NCNB); //SFR
- MMU_SetMTT(0x48000000,0x5af00000,0x48000000,RW_NCNB); //SFR
- MMU_SetMTT(0x5b000000,0xfff00000,0x5b000000,RW_FAULT);//not used
- MMU_SetTTBase(_MMUTT_STARTADDRESS);
- MMU_SetDomain(0x55555550|DOMAIN1_ATTR|DOMAIN0_ATTR);
- //DOMAIN1: no_access, DOMAIN0,2~15=client(AP is checked)
- MMU_SetProcessId(0x0);
- MMU_EnableAlignFault();
- MMU_EnableMMU();
- MMU_EnableICache();
- MMU_EnableDCache(); //DCache should be turned on after MMU is turned on.
- }
- // attr=RW_CB,RW_CNB,RW_NCNB,RW_FAULT
- void ChangeRomCacheStatus(int attr)
- {
- int i,j;
- MMU_DisableDCache();
- MMU_DisableICache();
- //If write-back is used,the DCache should be cleared.
- for(i=0;i<64;i++)
- for(j=0;j<8;j++)
- MMU_CleanInvalidateDCacheIndex((i<<26)|(j<<5));
- MMU_InvalidateICache();
- MMU_DisableMMU();
- MMU_InvalidateTLB();
- MMU_SetMTT(0x00000000,0x07f00000,0x00000000,attr); //bank0
- MMU_SetMTT(0x08000000,0x0ff00000,0x08000000,attr); //bank1
- MMU_EnableMMU();
- MMU_EnableICache();
- MMU_EnableDCache();
- }
- void MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr)
- {
- U32 *pTT;
- int i,nSec;
- pTT=(U32 *)_MMUTT_STARTADDRESS+(vaddrStart>>20);
- nSec=(vaddrEnd>>20)-(vaddrStart>>20);
- for(i=0;i<=nSec;i++)*pTT++=attr |(((paddrStart>>20)+i)<<20);
- }