ref: ada1920a0e4787d46402dcdc3e9f3ad3ddae7f0e
dir: /sys/src/9/mtx/l.s/
#include "mem.h" /* use of SPRG registers in save/restore */ #define SAVER0 SPRG0 #define SAVER1 SPRG1 #define SAVELR SPRG2 #define SAVEXX SPRG3 /* special instruction definitions */ #define BDNZ BC 16,0, #define BDNE BC 0,2, #define TLBIA WORD $((31<<26)|(307<<1)) #define TLBSYNC WORD $((31<<26)|(566<<1)) /* on some models mtmsr doesn't synchronise enough (eg, 603e) */ #define MSRSYNC SYNC; ISYNC #define UREGSPACE (UREGSIZE+8) TEXT start(SB), $-4 /* * setup MSR * turn off interrupts * use 0x000 as exception prefix * enable machine check */ MOVW MSR, R3 MOVW $(MSR_EE|MSR_IP), R4 ANDN R4, R3 OR $(MSR_ME), R3 ISYNC MOVW R3, MSR MSRSYNC /* except during trap handling, R0 is zero from now on */ MOVW $0, R0 /* setup SB for pre mmu */ MOVW $setSB(SB), R2 MOVW $KZERO, R3 ANDN R3, R2 BL mmuinit0(SB) /* running with MMU on!! */ /* set R2 to correct value */ MOVW $setSB(SB), R2 /* debugger sets R1 to top of usable memory +1 */ MOVW R1, memsize(SB) BL kfpinit(SB) /* set up Mach */ MOVW $mach0(SB), R(MACH) ADD $(MACHSIZE-8), R(MACH), R1 /* set stack */ MOVW R0, R(USER) MOVW R0, 0(R(MACH)) BL main(SB) RETURN /* not reached */ GLOBL mach0(SB), $(MAXMACH*BY2PG) GLOBL memsize(SB), $4 /* * on return from this function we will be running in virtual mode. * We set up the Block Address Translation (BAT) registers thus: * 1) first 3 BATs are 256M blocks, starting from KZERO->0 * 2) remaining BAT maps last 256M directly */ TEXT mmuinit0(SB), $0 /* reset all the tlbs */ MOVW $64, R3 MOVW R3, CTR MOVW $0, R4 tlbloop: TLBIE R4 ADD $BIT(19), R4 BDNZ tlbloop TLBSYNC /* KZERO -> 0 */ MOVW $(KZERO|(0x7ff<<2)|2), R3 MOVW $(PTEVALID|PTEWRITE), R4 MOVW R3, SPR(IBATU(0)) MOVW R4, SPR(IBATL(0)) MOVW R3, SPR(DBATU(0)) MOVW R4, SPR(DBATL(0)) /* KZERO+256M -> 256M */ ADD $(1<<28), R3 ADD $(1<<28), R4 MOVW R3, SPR(IBATU(1)) MOVW R4, SPR(IBATL(1)) MOVW R3, SPR(DBATU(1)) MOVW R4, SPR(DBATL(1)) /* KZERO+512M -> 512M */ ADD $(1<<28), R3 ADD $(1<<28), R4 MOVW R3, SPR(IBATU(2)) MOVW R4, SPR(IBATL(2)) MOVW R3, SPR(DBATU(2)) MOVW R4, SPR(DBATL(2)) /* direct map last block, uncached, (?guarded) */ MOVW $((0xf<<28)|(0x7ff<<2)|2), R3 MOVW $((0xf<<28)|PTE1_I|PTE1_G|PTE1_RW), R4 MOVW R3, SPR(DBATU(3)) MOVW R4, SPR(DBATL(3)) /* IBAT 3 unused */ MOVW R0, SPR(IBATU(3)) MOVW R0, SPR(IBATL(3)) /* enable MMU */ MOVW LR, R3 OR $KZERO, R3 MOVW R3, SPR(SRR0) MOVW MSR, R4 OR $(MSR_IR|MSR_DR), R4 MOVW R4, SPR(SRR1) RFI /* resume in kernel mode in caller */ RETURN TEXT kfpinit(SB), $0 MOVFL $0,FPSCR(7) MOVFL $0xD,FPSCR(6) /* VE, OE, ZE */ MOVFL $0, FPSCR(5) MOVFL $0, FPSCR(3) MOVFL $0, FPSCR(2) MOVFL $0, FPSCR(1) MOVFL $0, FPSCR(0) FMOVD $4503601774854144.0, F27 FMOVD $0.5, F29 FSUB F29, F29, F28 FADD F29, F29, F30 FADD F30, F30, F31 FMOVD F28, F0 FMOVD F28, F1 FMOVD F28, F2 FMOVD F28, F3 FMOVD F28, F4 FMOVD F28, F5 FMOVD F28, F6 FMOVD F28, F7 FMOVD F28, F8 FMOVD F28, F9 FMOVD F28, F10 FMOVD F28, F11 FMOVD F28, F12 FMOVD F28, F13 FMOVD F28, F14 FMOVD F28, F15 FMOVD F28, F16 FMOVD F28, F17 FMOVD F28, F18 FMOVD F28, F19 FMOVD F28, F20 FMOVD F28, F21 FMOVD F28, F22 FMOVD F28, F23 FMOVD F28, F24 FMOVD F28, F25 FMOVD F28, F26 RETURN TEXT splhi(SB), $0 MOVW LR, R31 MOVW R31, 4(R(MACH)) /* save PC in m->splpc */ MOVW MSR, R3 RLWNM $0, R3, $~MSR_EE, R4 SYNC MOVW R4, MSR MSRSYNC RETURN TEXT splx(SB), $0 /* fall though */ TEXT splxpc(SB), $0 MOVW LR, R31 MOVW R31, 4(R(MACH)) /* save PC in m->splpc */ MOVW MSR, R4 RLWMI $0, R3, $MSR_EE, R4 SYNC MOVW R4, MSR MSRSYNC RETURN TEXT spllo(SB), $0 MOVW MSR, R3 OR $MSR_EE, R3, R4 SYNC MOVW R4, MSR MSRSYNC RETURN TEXT spldone(SB), $0 RETURN TEXT islo(SB), $0 MOVW MSR, R3 RLWNM $0, R3, $MSR_EE, R3 RETURN TEXT setlabel(SB), $-4 MOVW LR, R31 MOVW R1, 0(R3) MOVW R31, 4(R3) MOVW $0, R3 RETURN TEXT gotolabel(SB), $-4 MOVW 4(R3), R31 MOVW R31, LR MOVW 0(R3), R1 MOVW $1, R3 RETURN TEXT touser(SB), $-4 MOVW $(UTZERO+32), R5 /* header appears in text */ MOVW $(MSR_EE|MSR_PR|MSR_ME|MSR_IR|MSR_DR|MSR_RI), R4 MOVW R4, SPR(SRR1) MOVW R3, R1 MOVW R5, SPR(SRR0) RFI TEXT icflush(SB), $-4 /* icflush(virtaddr, count) */ MOVW n+4(FP), R4 RLWNM $0, R3, $~(CACHELINESZ-1), R5 SUB R5, R3 ADD R3, R4 ADD $(CACHELINESZ-1), R4 SRAW $CACHELINELOG, R4 MOVW R4, CTR icf0: ICBI (R5) ADD $CACHELINESZ, R5 BDNZ icf0 ISYNC RETURN TEXT dcflush(SB), $-4 /* dcflush(virtaddr, count) */ MOVW n+4(FP), R4 RLWNM $0, R3, $~(CACHELINESZ-1), R5 CMP R4, $0 BLE dcf1 SUB R5, R3 ADD R3, R4 ADD $(CACHELINESZ-1), R4 SRAW $CACHELINELOG, R4 MOVW R4, CTR dcf0: DCBF (R5) ADD $CACHELINESZ, R5 BDNZ dcf0 dcf1: SYNC RETURN TEXT tas(SB), $0 TEXT _tas(SB), $0 SYNC MOVW R3, R4 MOVW $0xdead,R5 tas1: DCBF (R4) /* fix for 603x bug */ LWAR (R4), R3 CMP R3, $0 BNE tas0 STWCCC R5, (R4) BNE tas1 tas0: SYNC ISYNC RETURN TEXT cmpswap(SB),$0 /* int cmpswap(long*, long, long) */ MOVW R3, R4 /* addr */ MOVW old+4(FP), R5 MOVW new+8(FP), R6 DCBF (R4) /* fix for 603x bug? */ LWAR (R4), R3 CMP R3, R5 BNE fail STWCCC R6, (R4) BNE fail MOVW $1, R3 RETURN fail: MOVW $0, R3 RETURN TEXT getpvr(SB), $0 MOVW SPR(PVR), R3 RETURN TEXT getdec(SB), $0 MOVW SPR(DEC), R3 RETURN TEXT putdec(SB), $0 MOVW R3, SPR(DEC) RETURN TEXT getdar(SB), $0 MOVW SPR(DAR), R3 RETURN TEXT getdsisr(SB), $0 MOVW SPR(DSISR), R3 RETURN TEXT getmsr(SB), $0 MOVW MSR, R3 RETURN TEXT putmsr(SB), $0 SYNC MOVW R3, MSR MSRSYNC RETURN TEXT putsdr1(SB), $0 MOVW R3, SPR(SDR1) RETURN TEXT putsr(SB), $0 MOVW 4(FP), R4 MOVW R4, SEG(R3) RETURN TEXT gethid0(SB), $0 MOVW SPR(HID0), R3 RETURN TEXT gethid1(SB), $0 MOVW SPR(HID1), R3 RETURN TEXT puthid0(SB), $0 MOVW R3, SPR(HID0) RETURN TEXT puthid1(SB), $0 MOVW R3, SPR(HID1) RETURN TEXT eieio(SB), $0 EIEIO RETURN TEXT sync(SB), $0 SYNC RETURN TEXT tlbflushall(SB), $0 MOVW $64, R3 MOVW R3, CTR MOVW $0, R4 tlbflushall0: TLBIE R4 ADD $BIT(19), R4 BDNZ tlbflushall0 EIEIO TLBSYNC SYNC RETURN TEXT tlbflush(SB), $0 TLBIE R3 RETURN TEXT gotopc(SB), $0 MOVW R3, CTR MOVW LR, R31 /* for trace back */ BR (CTR) /* * traps force memory mapping off. * the following code has been executed at the exception * vector location * MOVW R0, SPR(SAVER0) * MOVW LR, R0 * MOVW R0, SPR(SAVELR) * bl trapvec(SB) */ TEXT trapvec(SB), $-4 MOVW LR, R0 MOVW R1, SPR(SAVER1) MOVW R0, SPR(SAVEXX) /* vector */ /* did we come from user space */ MOVW SPR(SRR1), R0 MOVW CR, R1 MOVW R0, CR BC 4,17,ktrap /* switch to kernel stack */ MOVW R1, CR MOVW R2, R0 MOVW $setSB(SB), R2 RLWNM $0, R2, $~KZERO, R2 /* PADDR(setSB) */ MOVW $mach0(SB), R1 /* m-> */ RLWNM $0, R1, $~KZERO, R1 /* PADDR(m->) */ MOVW 8(R1), R1 /* m->proc */ RLWNM $0, R1, $~KZERO, R1 /* PADDR(m->proc) */ SUB $UREGSIZE, R1 /* make room on stack */ MOVW R0, R2 BL saveureg(SB) BL trap(SB) BR restoreureg ktrap: MOVW R1, CR MOVW SPR(SAVER1), R1 RLWNM $0, R1, $~KZERO, R1 /* PADDR(R1) */ SUB $UREGSPACE, R1 BL saveureg(SB) BL trap(SB) BR restoreureg /* * enter with stack set and mapped. * on return, SB (R2) has been set, and R3 has the Ureg*, * the MMU has been re-enabled, kernel text and PC are in KSEG, * R(MACH) has been set, and R0 contains 0. * */ TEXT saveureg(SB), $-4 /* * save state */ MOVMW R2, 48(R1) /* r2:r31 */ MOVW $setSB(SB), R2 RLWNM $0, R2, $~KZERO, R2 /* PADDR(setSB) */ MOVW $mach0(SB), R(MACH) RLWNM $0, R(MACH), $~KZERO, R(MACH) /* PADDR(m->) */ MOVW 8(R(MACH)), R(USER) MOVW $mach0(SB), R(MACH) 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 CR, R5 MOVW R5, 28(R1) MOVW SPR(SAVELR), R6 /* LR */ MOVW R6, 24(R1) /* pad at 20(R1) */ MOVW SPR(SRR0), R0 MOVW R0, 16(R1) /* old PC */ MOVW SPR(SRR1), R0 MOVW R0, 12(R1) /* old status */ MOVW SPR(SAVEXX), R0 MOVW R0, 8(R1) /* cause/vector */ ADD $8, R1, R3 /* Ureg* */ OR $KZERO, R3 /* fix ureg */ STWCCC R3, (R1) /* break any pending reservations */ MOVW $0, R0 /* compiler/linker expect R0 to be zero */ MOVW MSR, R5 OR $(MSR_IR|MSR_DR|MSR_FP|MSR_RI), R5 /* enable MMU */ MOVW R5, SPR(SRR1) MOVW LR, R31 OR $KZERO, R31 /* return PC in KSEG0 */ MOVW R31, SPR(SRR0) OR $KZERO, R1 /* fix stack pointer */ RFI /* returns to trap handler */ /* * restore state from Ureg and return from trap/interrupt */ TEXT forkret(SB), $0 BR restoreureg restoreureg: 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, 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 */ MOVW SPR(SAVER0), R0 RFI TEXT fpsave(SB), $0 FMOVD F0, (0*8)(R3) FMOVD F1, (1*8)(R3) FMOVD F2, (2*8)(R3) FMOVD F3, (3*8)(R3) FMOVD F4, (4*8)(R3) FMOVD F5, (5*8)(R3) FMOVD F6, (6*8)(R3) FMOVD F7, (7*8)(R3) FMOVD F8, (8*8)(R3) FMOVD F9, (9*8)(R3) FMOVD F10, (10*8)(R3) FMOVD F11, (11*8)(R3) FMOVD F12, (12*8)(R3) FMOVD F13, (13*8)(R3) FMOVD F14, (14*8)(R3) FMOVD F15, (15*8)(R3) FMOVD F16, (16*8)(R3) FMOVD F17, (17*8)(R3) FMOVD F18, (18*8)(R3) FMOVD F19, (19*8)(R3) FMOVD F20, (20*8)(R3) FMOVD F21, (21*8)(R3) FMOVD F22, (22*8)(R3) FMOVD F23, (23*8)(R3) FMOVD F24, (24*8)(R3) FMOVD F25, (25*8)(R3) FMOVD F26, (26*8)(R3) FMOVD F27, (27*8)(R3) FMOVD F28, (28*8)(R3) FMOVD F29, (29*8)(R3) FMOVD F30, (30*8)(R3) FMOVD F31, (31*8)(R3) MOVFL FPSCR, F0 FMOVD F0, (32*8)(R3) RETURN TEXT fprestore(SB), $0 FMOVD (32*8)(R3), F0 MOVFL F0, FPSCR FMOVD (0*8)(R3), F0 FMOVD (1*8)(R3), F1 FMOVD (2*8)(R3), F2 FMOVD (3*8)(R3), F3 FMOVD (4*8)(R3), F4 FMOVD (5*8)(R3), F5 FMOVD (6*8)(R3), F6 FMOVD (7*8)(R3), F7 FMOVD (8*8)(R3), F8 FMOVD (9*8)(R3), F9 FMOVD (10*8)(R3), F10 FMOVD (11*8)(R3), F11 FMOVD (12*8)(R3), F12 FMOVD (13*8)(R3), F13 FMOVD (14*8)(R3), F14 FMOVD (15*8)(R3), F15 FMOVD (16*8)(R3), F16 FMOVD (17*8)(R3), F17 FMOVD (18*8)(R3), F18 FMOVD (19*8)(R3), F19 FMOVD (20*8)(R3), F20 FMOVD (21*8)(R3), F21 FMOVD (22*8)(R3), F22 FMOVD (23*8)(R3), F23 FMOVD (24*8)(R3), F24 FMOVD (25*8)(R3), F25 FMOVD (26*8)(R3), F26 FMOVD (27*8)(R3), F27 FMOVD (28*8)(R3), F28 FMOVD (29*8)(R3), F29 FMOVD (30*8)(R3), F30 FMOVD (31*8)(R3), F31 RETURN