1、/* bootInit.c - ROM initialization module */* Copyright 1989-2002 Wind River Systems, Inc. */#include “copyright_wrs.h“/*modification history-05h,26mar02,sbs correcting data section relocation for ROM compressed images(SPR 73785)05g,19mar02,dat Removing previous fix for MIPS, no longer needed (72825
2、)05f,18jan02,dat Dont use loop unrolling for MIPS05f,22jan02,scm Xscale specific validation added to update cache (to matchupdates.)05e,19dec01,aeg prevented pc-relative addressing on MC680X0.05d,10dec01,sbs Corrected conditions around call to copyLongs for ROM resident images.05c,27nov01,sbs Added
3、new labels, wrs_kernel_data_start and wrs_kernel_data_endfor sdata and edata respectively. Added second copy for data section of compressed ROM images. Corrected definition for binArrayEnd. Corrected definition for RESIDENT_DATA.05b,27nov01,tpw Manually unroll copyLongs and fillLongs.05a,25oct01,pad
4、 Removed definitions of _binArrayStart and _binArrayEnd, nowunnecessary.04z,03oct01,dee Merge from ColdFire T2.1.0 release04y,11jan01,scm Xscale specific validation added to update cache, can not assume uncached area04x,10jun99,jpd fix error when BOOTCODE_IN_RAM defined (SPR #27775).04w,13nov98,cdp
5、make Thumb support for ARM CPUs dependent on ARM_THUMB.04w,10feb99,db Fix to ensure that default bootline gets copied forstandalone and rom-resident images(SPR #21763).04v,05oct98,jmp doc: cleanup.04u,17apr98,cdp backed out 04t and made absEntry volatile for ARM.04t,16apr98,cdp for ARM, make UNCOMPR
6、ESS entry point in RAM.04s,20mar98,cdp make ROM_COPY_SIZE subject to #ifndef.04r,11nov97,cdp ARM7TDMI_T: force romStart to call entry point in Thumb state.(SPR# 9716)04q,14jul97,tam changed remaining references to bfillLong to fillLong. 04p,12feb97,dat Added USER_RESERVED_MEM, SYS_MEM_TOP, SYS_MEM_B
7、OTTOM, SPR 803004o,04feb97,ms fixed compiler warning about protoype for bcopyLongs.04o,28nov96,cdp added ARM support.04n,03sep96,hdn added the compression support for pc3486 BSP.04m,19aug96,ms added UNCMP_RTN macro to use inflate instead of uncompress04l,21jun96,jmb long modhist - deleted entries pr
8、ior to 1994. SPR #652803k,10jun96,tam added rom resident support for PPC architecture. 03j,14may96,dat fixed compiler warnings for copyLongs, fillLongs. SPR #653603i,06mar96,tpr changed absEntry to be volatile for PowerPC.03h,22aug95,hdn added support for I80X86.03g,14mar95,caf restored mips residen
9、t rom support (SPR #3856).03f,16feb95,jdi doc format change.03f,23may95,yao define binArrayStart and binArrayEnd for PowerPCbecause tools dont prepend “_“.03e,09dec94,caf undid mod 03a, use sdata for resident roms (SPR #3856).03d,22jun94,caf undid 16-byte alignment portion of mod 03c, below.03c,14ju
10、n94,cd corrected definitions of etext, edata and end.+caf for R4000 resident ROMs: data starts on 16-byte boundary.for R4000 uncompressed ROMs: added volatile to absEntry type.*/*DESCRIPTIONThis module provides a generic boot ROM facility. The target-specificromInit.s module performs the minimal pre
11、liminary board initialization andthen jumps to the C routine romStart(). This routine, still executing outof ROM, copies the first stage of the startup code to a RAM address andjumps to it. The next stage clears memory and then uncompresses theremainder of ROM into the final VxWorks ROM image in RAM
12、.A modified version of the Public Domain f3zlibfP library is used touncompress the VxWorks boot ROM executable linked with it. Compressingobject code typically achieves over 55% compression, permitting muchlarger systems to be burned into ROM. The only expense is the added fewseconds delay while the
13、 first two stages complete.ROM AND RAM MEMORY LAYOUTExample memory layout for a 1-megabyte board:.CS- 0x00100000 = LOCAL_MEM_SIZE = sysMemTop()| | RAM | 0 filled | |-| = (romInit+ROM_COPY_SIZE) or binArrayStart| ROM image |- | 0x00090000 = RAM_HIGH_ADRS| STACK_SAVE |-| | 0x00080000 = 0.5 Megabytes|
14、| | 0 filled | | | 0x00001000 = RAM_ADRS IMPORT STATUS UNCMP_RTN ();IMPORT void usrInit ();IMPORT void sysInitAlt ();IMPORT void start ();IMPORT UCHAR binArrayStart ; /* compressed binary image */IMPORT UCHAR binArrayEnd ; /* end of compressed binary image */IMPORT char etext ; /* defined by the loa
15、der */IMPORT char end ; /* defined by the loader */IMPORT UCHAR wrs_kernel_data_start ; /* defined by the loader */IMPORT UCHAR wrs_kernel_data_end ; /* defined by the loader */#if (CPU_FAMILY = MIPS) | (CPU_FAMILY=PPC) | (CPU_FAMILY=COLDFIRE)#define RESIDENT_DATA RAM_DST_ADRS /定义体系结构特殊信息=压缩映象最终重定位的
16、地址#else#define RESIDENT_DATA wrs_kernel_data_start#endif#ifndef RAM_DST_ADRS /* default uncompress dest. */#define RAM_DST_ADRS RAM_HIGH_ADRS /压缩映象最终重定位的地址= 拷贝引导映象的入口地址#endif/* If the boot code is in RAM and the RAM is already initialized,* clearing the RAM is not necessary. Macro BOOTCODE_IN_RAM is
17、* used not to clear the RAM.*/#ifdef BOOTCODE_IN_RAM /* not to clear RAM */#undef ROM_TEXT_ADRS#undef ROM_BASE_ADRS#define ROM_TEXT_ADRS (UINT)romInit)#define ROM_BASE_ADRS (UINT)romInit) /引导 rom 的入口地址#endif /* BOOTCODE_IN_RAM */* #if defined (UNCOMPRESS) | defined (ROM_RESIDENT) */#ifndef ROM_COPY_
18、SIZE#define ROM_COPY_SIZE (ROM_SIZE - (ROM_TEXT_ADRS - ROM_BASE_ADRS)#endif/* #endif*/ /* UNCOMPRESS */#define ROM_OFFSET(adr) (UINT)adr - (UINT)romInit) + ROM_TEXT_ADRS) /rom-ram时涉及到计算偏移地址函数,重定位了 adr 在 rom 当中的位置 ;/* forward declarations */LOCAL void copyLongs (FAST UINT *source, FAST UINT *destinat
19、ion, UINT nlongs);/拷贝rom-ram 函数#ifndef BOOTCODE_IN_RAMLOCAL void fillLongs (FAST UINT *buf, UINT nlongs, FAST UINT val);/往 ram 填零函数#endif /* BOOTCODE_IN_RAM */#if (CPU=XSCALE)int checkLongs (FAST UINT *source, FAST UINT *destination, UINT nlongs);/比较函数#endif/* romStart - generic ROM initialization*
20、This is the first C code executed after reset.* This routine is called by the assembly start-up code in romInit().* It clears memory, copies ROM to RAM, and possibly invokes the uncompressor.* It then jumps to the entry point of the uncompressed object code.* RETURNS: N/A*/void romStart(FAST int sta
21、rtType /* 启动类型，它的入口参数是 startType，是一个启动类型标志，这在后面清内存时会用到*/ )#if (CPU_FAMILY=SPARC) | (CPU_FAMILY=MIPS) | (CPU_FAMILY=I80X86) | (CPU_FAMILY=PPC) | (CPU_FAMILY=ARM)volatile /* to force absolute adressing */#endif /* (CPU_FAMILY=SPARC) */FUNCPTR absEntry; /* to avoid PC Relative Jump Subroutine */ /函数指针变
22、量 absEntry，它最后指向 ursInit()或 compressedEntry()函数#if (CPU_FAMILY=ARM) /* force call to RAM */#define fillLongs(a,b,c) ramfillLongs(a,b,c)#endif /* (CPU_FAMILY=ARM) */#if (CPU_FAMILY=MC680X0) /* force call to ROM */#define copyLongs romcopyLongs#endif /* (CPU_FAMILY=MC680X0) */* Copy from ROM to RAM, m
23、inus the compressed image* if compressed boot ROM which relies on binArray* appearing last in DATA segment.*/#ifdef ROM_RESIDENT/* If ROM resident code, then copy only data segment* from ROM to RAM, initialize memory and jump* to usrInit.*/#if (CPU_FAMILY = SPARC)copyLongs (UINT *)(etext + 8), (UINT
24、 *) RESIDENT_DATA,#elsecopyLongs (UINT *)etext, (UINT *) RESIDENT_DATA,#endif(UINT) wrs_kernel_data_end - (UINT) RESIDENT_DATA) / sizeof (long);#else /* ROM_RESIDENT */#ifdef UNCOMPRESS#if (CPU_FAMILY = MIPS)/* copy text to uncached locations to avoid problems with* copy back caches*/(FUNCPTR)ROM_OF
25、FSET(copyLongs) (ROM_TEXT_ADRS, (UINT)K0_TO_K1(romInit),ROM_COPY_SIZE / sizeof (long);#else /* CPU_FAMILY = MIPS */(FUNCPTR)ROM_OFFSET(copyLongs) (ROM_TEXT_ADRS, (UINT)romInit,ROM_COPY_SIZE / sizeof (long);#endif /* CPU_FAMILY = MIPS */#else /* UNCOMPRESS */#if (CPU_FAMILY = MIPS)/* copy text to unc
26、ached locations to avoid problems with* copy back caches* copy the entire data segment because there is no way to ensure that* binArray is the last thing in the data segment because of GP relative* addressing*/(FUNCPTR)ROM_OFFSET(copyLongs) (ROM_TEXT_ADRS, (UINT)K0_TO_K1(romInit),(UINT)wrs_kernel_da
27、ta_end - (UINT)romInit) / sizeof (long);#else /* CPU_FAMILY = MIPS */(FUNCPTR)ROM_OFFSET(copyLongs) (ROM_TEXT_ADRS, (UINT)romInit, /(FUNCPTR)为 int (*)()型的函数指针； ROM_OFFSET 为 rom-ram 时涉及到计算偏移地址函数，重定位了 copyLongs 在 rom 当中的位置；/(copyLongs)为拷贝 rom-ram 函数；ROM_TEXT_ADRS 为拷贝内容 rom 入口地址；(UINT)romInit 为 ram 目标地
28、址(UINT)binArrayStart - (UINT)romInit)/ sizeof (long); /非压缩镜像大小，binArrayStart 为压缩部分起始地址； /rom-ram 代码段部分；(FUNCPTR)ROM_OFFSET(copyLongs) (UINT *)(UINT)ROM_TEXT_ADRS + (UINT)BINARRAYEND_ROUNDOFF - /(UINT)BINARRAYEND_ROUNDOFF 为 ram 中压缩部分之后目标地址；(UINT)romInit), (UINT *)BINARRAYEND_ROUNDOFF, (UINT)wrs_kerne
29、l_data_end - (UINT)binArrayEnd) / sizeof (long);#if (CPU=XSCALE)/* validate coherence, can not assume uncached area. */(FUNCPTR)ROM_OFFSET(checkLongs)(ROM_TEXT_ADRS, (UINT)romInit,(UINT)binArrayStart - (UINT)romInit) / sizeof (long);(FUNCPTR)ROM_OFFSET(checkLongs)(UINT *)(UINT)ROM_TEXT_ADRS + (UINT)
30、BINARRAYEND_ROUNDOFF - (UINT)romInit), (UINT *)BINARRAYEND_ROUNDOFF,(UINT)wrs_kernel_data_end - (UINT)binArrayEnd) / sizeof (long);#endif#endif /* CPU_FAMILY = MIPS */#endif /* UNCOMPRESS */#endif /* ROM_RESIDENT */#if (CPU_FAMILY != MIPS) fillLongs (UINT *) wrs_kernel_data_end),(UINT)SYS_MEM_TOP -
31、(UINT) wrs_kernel_data_end) / sizeof(long), 0);#else /* ROM_RESIDENT */fillLongs (UINT *)(SYS_MEM_BOTTOM),(UINT)romInit - STACK_SAVE - (UINT)SYS_MEM_BOTTOM) /sizeof(long), 0); /实现了从SYS_MEM_BOTTOM 到 STACK_SAVE 之前 RAM 的清零#if defined (UNCOMPRESS)fillLongs (UINT *)(UINT)romInit + ROM_COPY_SIZE),(UINT)SY
32、S_MEM_TOP - (UINT)romInit + ROM_COPY_SIZE)/ sizeof(long), 0); #elsefillLongs (UINT *)wrs_kernel_data_end, /实现了从数据段到SYS_MEM_TOP 的 RAM 区清零 (UINT)SYS_MEM_TOP - (UINT)wrs_kernel_data_end) / sizeof (long), 0);#endif /* UNCOMPRESS */#endif /* ROM_RESIDENT */* * Ensure the boot line is null. This is necess
33、ary for those* targets whose boot line is excluded from cleaning.*/*(BOOT_LINE_ADRS) = EOS;#endif /* (CPU_FAMILY != MIPS) /* reinit proc tbl */#elseabsEntry = (FUNCPTR)usrInit; /* on to bootConfig */#endif /* CPU_FAMILY = I960 */#else#if (CPU_FAMILY = MIPS)volatile FUNCPTR absUncompress = (FUNCPTR)
34、UNCMP_RTN;if (absUncompress) (UCHAR *)ROM_OFFSET(binArrayStart),(UCHAR *)K0_TO_K1(RAM_DST_ADRS),(int)(UINT)binArrayEnd - (UINT)binArrayStart) != OK)#elif (CPU_FAMILY = I80X86) | (CPU_FAMILY = ARM)volatile FUNCPTR absUncompress = (FUNCPTR) UNCMP_RTN; / UNCMP_RTN 为原形函数为 int inflate(Byte * src,Byte * d
35、est,int nBytes)if (absUncompress) (UCHAR *)ROM_OFFSET(binArrayStart), /ROM_OFFSET(binArrayStart 为压缩文件起始地址，在 rom 中需要重定向；(UCHAR *)RAM_DST_ADRS, binArrayEnd - binArrayStart) != OK) /解压缩过程，RAM_DST_ADRS 目标地址；#elseif (UNCMP_RTN (UCHAR *)ROM_OFFSET(binArrayStart),(UCHAR *)RAM_DST_ADRS, binArrayEnd - binArr
36、ayStart) != OK)#endif /* (CPU_FAMILY = MIPS) */return; /* if we return then ROMs will halt */absEntry = (FUNCPTR)RAM_DST_ADRS; /* compressedEntry () 程序的入口地址就是 RAM_DST_ADRS */ #endif /* defined UNCOMPRESS | defined ROM_RESIDENT */#if (CPU_FAMILY = ARM) /* force Thumb state */#endif /* CPU_FAMILY = AR
37、M */(absEntry) (startType);#if (CPU_FAMILY=ARM) /* pointer to source buffer */FAST UINT *destination; /* pointer to destination buffer */UINT nlongs; /* number of longs to copy */FAST UINT *dstend = destination + nlongs;FAST UINT nchunks;/* Hop by chunks of longs, for speed. */for (nchunks = nlongs
38、/ 8; nchunks; -nchunks)#if (CPU_FAMILY = MC680X0)*destination+ = *source+; /* 0 */*destination+ = *source+; /* 1 */*destination+ = *source+; /* 2 */*destination+ = *source+; /* 3 */*destination+ = *source+; /* 4 */*destination+ = *source+; /* 5 */*destination+ = *source+; /* 6 */*destination+ = *sou
39、rce+; /* 7 */#elsedestination0 = source0;destination1 = source1;destination2 = source2;destination3 = source3;destination4 = source4;destination5 = source5;destination6 = source6;destination7 = source7;destination += 8, source += 8;#endif /* CPU_FAMILY = MC680X0 */* Do the remainder one long at a ti
40、me. */while (destination longs of the buffer with .*/LOCAL void fillLongs (buf, nlongs, val)FAST UINT *buf; /* pointer to buffer */UINT nlongs; /* number of longs to fill */FAST UINT val; /* char with which to fill buffer */FAST UINT *bufend = buf + nlongs;FAST UINT nchunks;/* Hop by chunks of longs
41、, for speed. */for (nchunks = nlongs / 8; nchunks; -nchunks)#if (CPU_FAMILY = MC680X0)*buf+ = val; /* 0 */*buf+ = val; /* 1 */*buf+ = val; /* 2 */*buf+ = val; /* 3 */*buf+ = val; /* 4 */*buf+ = val; /* 5 */*buf+ = val; /* 6 */*buf+ = val; /* 7 */#elsebuf0 = val;buf1 = val;buf2 = val;buf3 = val;buf4
42、= val;buf5 = val;buf6 = val;buf7 = val;buf += 8;#endif /* CPU_FAMILY = MC680X0 */* Do the remainder one long at a time. */while (buf bufend)*buf+ = val;#endif /* BOOTCODE_IN_RAM */#if (CPU=XSCALE)int checkLongs (source, destination, nlongs)FAST UINT *source; /* pointer to source buffer */FAST UINT *destination; /* pointer to destination buffer */UINT nlongs; /* number of longs to copy */int fine = 1;FAST UINT *dstend = destination + nlongs;while (destination dstend)if (*destination+ != *source+)fine = 0;break;return fine;#endif
