ref: 8a788aea84aad3bfbd5b39d78c1925654f3b9e14
dir: /os/boot/mpc/l.s/
#include "mem.h" /* special instruction definitions */ #define BDNE BC 0,2, #define BDNZ BC 16,0, #define NOOP OR R0,R0,R0 /* * common ppc special purpose registers */ #define DSISR 18 #define DAR 19 /* Data Address Register */ #define DEC 22 /* Decrementer */ #define SRR0 26 /* Saved Registers (exception) */ #define SRR1 27 #define SPRG0 272 /* Supervisor Private Registers */ #define SPRG1 273 #define SPRG2 274 #define SPRG3 275 #define TBRU 269 /* Time base Upper/Lower (Reading) */ #define TBRL 268 #define TBWU 285 /* Time base Upper/Lower (Writing) */ #define TBWL 284 #define PVR 287 /* Processor Version */ /* * mpc82x-specific special purpose registers of interest here */ #define EIE 80 #define EID 81 #define NRI 82 #define IMMR 638 #define IC_CST 560 #define IC_ADR 561 #define IC_DAT 562 #define DC_CST 568 #define DC_ADR 569 #define DC_DAT 570 #define MI_CTR 784 #define MI_AP 786 #define MI_EPN 787 #define MI_TWC 789 #define MI_RPN 790 #define MI_DBCAM 816 #define MI_DBRAM0 817 #define MI_DBRAM1 818 #define MD_CTR 792 #define M_CASID 793 #define MD_AP 794 #define MD_EPN 795 #define M_TWB 796 #define MD_TWC 797 #define MD_RPN 798 #define M_TW 799 #define MD_DBCAM 824 #define MD_DBRAM0 825 #define MD_DBRAM1 826 /* as on 603e, apparently mtmsr needs help in some chip revisions */ #define WAITMSR SYNC; ISYNC /* use of SPRG registers in save/restore */ #define SAVER0 SPRG0 #define SAVER1 SPRG1 #define SAVELR SPRG2 #define SAVECR SPRG3 #define UREGSIZE ((8+32)*4) #define UREGSPACE (UREGSIZE+8) /* allow for arg to trap, and align */ /* * This code is loaded by the ROM loader at location 0x3000, * or lives in flash memory at 0x2800100. * Move it to high memory so that it can load the kernel at 0x0000. */ #define LOADCODEBASE 0x3000 /* when downloaded in S records */ #define FLASHCODEBASE (FLASHMEM+0x100) /* when in flash */ TEXT start(SB), $-4 MOVW MSR, R3 MOVW $(EE|IP|RI), R4 ANDN R4, R3 OR $ME, R3 SYNC MOVW R3, MSR /* turn off interrupts but enable traps */ WAITMSR /* * reset the caches and disable them for now */ MOVW SPR(IC_CST), R4 /* read and clear */ MOVW $(5<<25), R4 MOVW R4, SPR(IC_CST) /* unlock all */ ISYNC MOVW $(6<<25), R4 MOVW R4, SPR(IC_CST) /* invalidate all */ ISYNC MOVW $(2<<25), R4 MOVW R4, SPR(IC_CST) /* disable i-cache */ ISYNC SYNC MOVW SPR(DC_CST), R4 /* read and clear */ MOVW $(10<<24), R4 MOVW R4, SPR(DC_CST) /* unlock all */ ISYNC MOVW $(12<<24), R4 MOVW R4, SPR(DC_CST) /* invalidate all */ ISYNC MOVW $(4<<24), R4 MOVW R4, SPR(DC_CST) /* disable i-cache */ ISYNC MOVW $7, R4 ANDN R4, R4, R4 MOVW R4, SPR(158) /* cancel `show cycle' for normal instruction execution */ /* * set other system configuration values */ MOVW SPR(IMMR), R5 /* save initial space pointer */ MOVW $INTMEM, R4 MOVW R4, SPR(IMMR) /* set internal memory base */ MOVW $0xFFFFFF88, R3 MOVW R3, 4(R4) /* disable watchdog in sypcr */ MOVW $0x01012440, R3 MOVW R3, 0(R4) /* siumcr */ /* * system initialisation (init and map DRAM) */ MOVW $0, R0 MOVW $setSB(SB), R2 MOVW $(0xF000<<16), R3 /*MOVW R0, R3*/ ANDCC R5, R3 /* initial space is high? */ BEQ notrom MOVW $FLASHCODEBASE, R5 /* where $start(SB) actually is now */ MOVW $start(SB), R4 /* logical start address */ SUB R4, R5, R6 /* text relocation value */ MOVW $etext(SB), R7 SUB R4, R7 ADD R5, R7 /* data address in ROM */ MOVW $bdata(SB), R8 SUB R8, R2 ADD R7, R2 /* relocate SB: SB' = romdata+(SB-bdata) */ MOVW $sysinit0(SB), R4 ADD R6, R4 /* relocate sysinit0's address */ MOVW R4, CTR MOVW $inmem(SB), R4 ADD R6, R4 MOVW R4, LR /* and the return address */ BR (CTR) /* call sysinit0 */ TEXT inmem(SB), $-4 MOVW $FLASHCODEBASE, R3 BR cpu0 notrom: MOVW $start(SB), R6 SUB R6, R2 ADD $LOADCODEBASE, R2 BL sysinit0(SB) MOVW $LOADCODEBASE, R3 /* * cpu 0 * relocate bootstrap to our link addresses for text and data * set new PC */ cpu0: MOVW $setSB(SB), R2 /* set correct static base register */ MOVW $start(SB), R4 MOVW $etext(SB), R5 SUB R4, R5 CMP R4, R3 /* already there? */ BNE copytext ADD R5, R3 /* start of data image */ BR copydata copytext: ADD $3, R5 SRAW $2, R5 MOVW R5, CTR SUB $4, R4 SUB $4, R3 copyt: /* copy text */ MOVWU 4(R3), R5 MOVWU R5, 4(R4) BDNZ copyt ADD $4, R3 copydata: /* copy data */ MOVW $bdata(SB), R4 CMP R4, R3 /* already there? */ BEQ loadkpc MOVW $edata(SB), R5 SUB R4, R5 ADD $3, R5 SRAW $2, R5 MOVW R5, CTR SUB $4, R4 SUB $4, R3 copyd: MOVWU 4(R3), R5 MOVWU R5, 4(R4) BDNZ copyd /* load correct PC */ loadkpc: MOVW $start1(SB), R3 MOVW R3, LR BR (LR) TEXT start1(SB), $-4 MOVW $edata(SB), R3 MOVW $end(SB), R4 SUBCC R3, R4 BLE skipz SRAW $2, R4 MOVW R4, CTR SUB $4, R3 MOVW $0, R0 zero: MOVWU R0, 4(R3) BDNZ zero skipz: MOVW $mach0(SB), R1 MOVW R1, m(SB) ADD $(MACHSIZE-8), R1 MOVW $0, R0 BL main(SB) BR 0(PC) TEXT getmsr(SB), $0 MOVW MSR, R3 RETURN TEXT putmsr(SB), $0 SYNC MOVW R3, MSR WAITMSR RETURN TEXT eieio(SB), $0 EIEIO RETURN TEXT idle(SB), $0 RETURN TEXT spllo(SB), $0 MOVW MSR, R3 OR $EE, R3, R4 SYNC MOVW R4, MSR WAITMSR RETURN TEXT splhi(SB), $0 MOVW MSR, R3 RLWNM $0, R3, $~EE, R4 SYNC MOVW R4, MSR WAITMSR RETURN TEXT splx(SB), $0 MOVW MSR, R4 RLWMI $0, R3, $EE, R4 SYNC MOVW R4, MSR WAITMSR RETURN TEXT gettbl(SB), $0 /* MOVW SPR(TBRL), R3 */ WORD $0x7c6c42e6 /* mftbl on 8xx series */ RETURN TEXT getpvr(SB), $0 MOVW SPR(PVR), R3 RETURN TEXT getimmr(SB), $0 MOVW SPR(IMMR), R3 RETURN TEXT getdec(SB), $0 MOVW SPR(DEC), R3 RETURN TEXT putdec(SB), $0 MOVW R3, SPR(DEC) RETURN /* * save state in Ureg on kernel stack. * enter with R0 giving the PC from the call to `exception' from the vector. * on return, SB (R2) has been set, and R3 has the Ureg* */ TEXT saveureg(SB), $-4 SUB $UREGSPACE, R1 MOVMW R2, 48(R1) /* r2:r31 */ MOVW $setSB(SB), R2 MOVW SPR(SAVER1), R4 MOVW R4, 44(R1) MOVW SPR(SAVER0), R5 MOVW R5, 40(R1) MOVW CTR, R6 MOVW R6, 36(R1) MOVW XER, R4 MOVW R4, 32(R1) MOVW SPR(SAVECR), R5 /* CR */ MOVW R5, 28(R1) MOVW SPR(SAVELR), R6 /* LR */ MOVW R6, 24(R1) /* pad at 20(R1) */ MOVW SPR(SRR0), R4 MOVW R4, 16(R1) /* old PC */ MOVW SPR(SRR1), R5 MOVW R5, 12(R1) MOVW R0, 8(R1) /* cause/vector, encoded in LR from vector */ ADD $8, R1, R3 /* Ureg* */ STWCCC R3, (R1) /* break any pending reservations */ MOVW $0, R0 /* R0ISZERO */ BR (LR) /* * restore state from Ureg * SB (R2) is unusable on return */ TEXT restoreureg(SB), $-4 MOVMW 48(R1), R2 /* r2:r31 */ /* defer R1 */ MOVW 40(R1), R0 MOVW R0, SPR(SAVER0) MOVW 36(R1), R0 MOVW R0, CTR MOVW 32(R1), R0 MOVW R0, XER MOVW 28(R1), R0 MOVW R0, CR /* CR */ MOVW 24(R1), R0 MOVW R0, SPR(SAVELR) /* LR */ /* pad, skip */ MOVW 16(R1), R0 MOVW R0, SPR(SRR0) /* old PC */ MOVW 12(R1), R0 MOVW R0, SPR(SRR1) /* old MSR */ /* cause, skip */ MOVW 44(R1), R1 /* old SP */ BR (LR) TEXT exception(SB), $-4 MOVW R1, SPR(SAVER1) MOVW CR, R0 MOVW R0, SPR(SAVECR) MOVW LR, R0 BL saveureg(SB) MOVW $0, R0 BL trap(SB) BL restoreureg(SB) MOVW SPR(SAVELR), R0 MOVW R0, LR MOVW SPR(SAVER0), R0 ISYNC RFI GLOBL mach0+0(SB), $MACHSIZE GLOBL m(SB), $4