/* $NetBSD: locore.s,v 1.83 2024/01/19 18:18:54 thorpej Exp $ */ /* * Copyright (c) 1988 University of Utah. * Copyright (c) 1980, 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: Utah $Hdr: locore.s 1.66 92/12/22$ * * @(#)locore.s 8.6 (Berkeley) 5/27/94 */ #include "opt_compat_netbsd.h" #include "opt_compat_sunos.h" #include "opt_ddb.h" #include "opt_fpsp.h" #include "opt_kgdb.h" #include "opt_lockdebug.h" #include "opt_fpu_emulate.h" #include "opt_m68k_arch.h" #include "assym.h" #include #include #include #include "ksyms.h" #define PRINT(msg) \ pea 9f ; \ jbsr _C_LABEL(printf); \ addl #4,%sp ; \ .data ; \ 9: .asciz msg ; \ .text #undef PRINT /* * Temporary stack for a variety of purposes. * Try and make this the first thing is the data segment so it * is page aligned. Note that if we overflow here, we run into * our text segment. */ .data .space PAGE_SIZE ASLOCAL(tmpstk) /* * Macro to relocate a symbol, used before MMU is enabled. */ #define _RELOC(var,ar) \ lea var,ar; \ addl %a5,ar #define RELOC(var,ar) _RELOC(_C_LABEL(var), ar) #define ASRELOC(var,ar) _RELOC(_ASM_LABEL(var), ar) BSS(lowram,4) BSS(esym,4) /* * This is for kvm_mkdb, and should be the address of the beginning * of the kernel text segment (not necessarily the same as kernbase). */ .text GLOBAL(kernel_text) /* * start of kernel and .text! */ ASENTRY_NOPROFILE(start) movw #PSL_HIGHIPL,%sr | no interrupts movl #0,%a5 | RAM starts at 0 ASRELOC(tmpstk,%a0) movl %a0,%sp | give ourselves a temporary stack RELOC(edata,%a0) | clear out BSS movl #_C_LABEL(end)-4,%d0 | (must be <= 256 kB) subl #_C_LABEL(edata),%d0 lsrl #2,%d0 1: clrl %a0@+ dbra %d0,1b RELOC(boothowto,%a0) movl %d7,%a0@ | save boothowto RELOC(bootdev,%a0) movl %d6,%a0@ | save bootdev RELOC(lowram,%a0) movl %a5,%a0@ | store start of physical memory movl #PROM_ADDR,%a0 | available memory in bytes movl %a0@(12),%a0 | (int *)base[3]) movl %a0@,%d5 RELOC(memavail,%a0) movl %d5,%a0@ | save memavail movl #PROM_ADDR,%a0 | planemask; 0x0f or 0xff movl %a0@(184),%a0 | (int *)base[46] movl %a0@,%d5 RELOC(hwplanemask,%a0) movl %d5,%a0@ | save hwplanemask movl #CACHE_OFF,%d0 movc %d0,%cacr | clear and disable on-chip cache(s) /* determine our CPU/MMU combo - check for all regardless of kernel config */ movl #DC_FREEZE,%d0 | data freeze bit movc %d0,%cacr | only exists on 68030 movc %cacr,%d0 | read it back tstl %d0 | zero? jeq Lnot68030 | yes, we have 68040 movl #CPU_68030,%d0 movl #MMU_68030,%d1 movl #FPU_68881,%d2 jra Lstart0 Lnot68030: movl #CPU_68040,%d0 movl #MMU_68040,%d1 movl #FPU_68040,%d2 Lstart0: RELOC(cputype,%a0) movl %d0,%a0@ RELOC(mmutype,%a0) movl %d1,%a0@ RELOC(fputype,%a0) movl %d2,%a0@ /* * save argument of 'x' command on boot per machine type * XXX: assume CPU_68040 is LUNA-II */ movl #PROM_ADDR,%a0 cmpl #CPU_68040,%d0 | 68040? jne 1f | no, assume 68030 LUNA movl %a0@(8),%a0 | arg at (char *)base[2] on LUNA-II jra Lstart1 1: movl %a0@(212),%a0 | arg at (char *)base[53] on LUNA Lstart1: RELOC(bootarg,%a1) movl #63,%d0 1: movb %a0@+,%a1@+ | copy to bootarg dbra %d0,1b | upto 63 characters /* initialize source/destination control registers for movs */ moveq #FC_USERD,%d0 | user space movc %d0,%sfc | as source movc %d0,%dfc | and destination of transfers /* initialize memory sizes (for pmap_bootstrap) */ RELOC(memavail,%a0) movl %a0@,%d1 moveq #PGSHIFT,%d2 lsrl %d2,%d1 | convert to page (click) number RELOC(maxmem,%a0) movl %d1,%a0@ | save as maxmem RELOC(physmem,%a0) movl %d1,%a0@ | and physmem /* check if symbol table is loaded and set esym address */ #if NKSYMS || defined(DDB) || defined(MODULAR) RELOC(end,%a0) pea %a0@ RELOC(_C_LABEL(symtab_size),%a0) jbsr %a0@ | symtab_size(end) addql #4,%sp tstl %d0 | check if valid symtab is loaded jeq 1f | no, skip lea _C_LABEL(end),%a0 | calculate end of symtab address addl %a0,%d0 #else clrl %d0 | no symbol table #endif 1: RELOC(esym,%a0) movl %d0,%a0@ /* configure kernel and lwp0 VA space so we can get going */ #if NKSYMS || defined(DDB) || defined(MODULAR) RELOC(esym,%a0) | end of static kernel test/data/syms movl %a0@,%d2 jne Lstart3 #endif RELOC(end,%a0) movl %a0,%d2 | end of static kernel text/data Lstart3: addl #PAGE_SIZE-1,%d2 andl #PG_FRAME,%d2 | round to a page movl %d2,%a4 addl %a5,%a4 | convert to PA pea %a5@ | firstpa pea %a4@ | nextpa RELOC(pmap_bootstrap,%a0) jbsr %a0@ | pmap_bootstrap(firstpa, nextpa) addql #8,%sp /* * Enable the MMU. * Since the kernel is mapped logical == physical, we just turn it on. */ RELOC(Sysseg_pa,%a0) | system segment table addr movl %a0@,%d1 | read value (a PA) #if defined(M68040) RELOC(mmutype,%a0) cmpl #MMU_68040,%a0@ | 68040? jne Lmotommu1 | no, skip Lmotommu0: .long 0x4e7b1807 | movc %d1,%srp RELOC(proto040tt0,%a0) movl %a0@,%d0 | tt0 range 4000.0000-7fff.ffff .long 0x4e7b0004 | movc %d0,%itt0 .long 0x4e7b0006 | movc %d0,%dtt0 RELOC(proto040tt1,%a0) movl %a0@,%d0 | tt1 range 8000.0000-ffff.ffff .long 0x4e7b0005 | movc %d0,%itt1 .long 0x4e7b0007 | movc %d0,%dtt1 .word 0xf4d8 | cinva bc .word 0xf518 | pflusha RELOC(proto040tc,%a0) movl %a0@,%d0 .long 0x4e7b0003 | movc %d0,%tc movl #CACHE40_ON,%d0 movc %d0,%cacr | turn on both caches jmp Lenab1 Lmotommu1: #endif RELOC(protorp,%a0) movl %d1,%a0@(4) | segtable address pmove %a0@,%srp | load the supervisor root pointer RELOC(protott0,%a0) | tt0 range 4000.0000-7fff.ffff .long 0xf0100800 | pmove %a0@,mmutt0 RELOC(protott1,%a0) | tt1 range 8000.0000-ffff.ffff .long 0xf0100c00 | pmove %a0@,mmutt1 pflusha RELOC(prototc,%a0) | %tc: SRP,CRP,4KB or 8KB page pmove %a0@,%tc /* * Should be running mapped from this point on */ Lenab1: lea _ASM_LABEL(tmpstk),%sp | re-load temporary stack jbsr _C_LABEL(vec_init) | initialize vector table /* call final pmap setup */ jbsr _C_LABEL(pmap_bootstrap_finalize) /* set kernel stack, user SP */ movl _C_LABEL(lwp0uarea),%a1 | get lwp0 uarea lea %a1@(USPACE-4),%sp | set kernel stack to end of area movl #USRSTACK-4,%a2 movl %a2,%usp | init user SP /* detect FPU type */ jbsr _C_LABEL(fpu_probe) movl %d0,_C_LABEL(fputype) tstl _C_LABEL(fputype) | Have an FPU? jeq Lenab2 | No, skip. clrl %a1@(PCB_FPCTX) | ensure null FP context movl %a1,%sp@- jbsr _C_LABEL(m68881_restore) | restore it (does not kill %a1) addql #4,%sp Lenab2: jbsr _C_LABEL(_TBIA) | invalidate TLB cmpl #MMU_68040,_C_LABEL(mmutype) | 68040? jeq Lenab3 | yes, cache already on tstl _C_LABEL(mmutype) jpl Lenab3 | 68851 implies no d-cache movl #CACHE_ON,%d0 movc %d0,%cacr | clear cache(s) Lenab3: /* final setup for C code */ jbsr _C_LABEL(luna68k_init) | additional pre-main initialization /* * Create a fake exception frame that returns to user mode, * and save its address in p->p_md.md_regs for cpu_lwp_fork(). * The new frames for process 1 and 2 will be adjusted by * cpu_set_kpc() to arrange for a call to a kernel function * before the new process does its rte out to user mode. */ clrw %sp@- | vector offset/frame type clrl %sp@- | PC - filled in by "execve" movw #PSL_USER,%sp@- | in user mode clrl %sp@- | stack adjust count and padding lea %sp@(-64),%sp | construct space for D0-D7/A0-A7 lea _C_LABEL(lwp0),%a0 | save pointer to frame movl %sp,%a0@(L_MD_REGS) | in lwp0.l_md.md_regs jra _C_LABEL(main) | main() PANIC("main() returned") /* NOTREACHED */ /* * Trap/interrupt vector routines */ #include /* * Use common m68k bus error and address error handlers. */ #include /* * FP exceptions. */ ENTRY_NOPROFILE(fpfline) #if defined(M68040) cmpl #FPU_68040,_C_LABEL(fputype) | 68040 FPU? jne Lfp_unimp | no, skip FPSP cmpw #0x202c,%sp@(6) | format type 2? jne _C_LABEL(illinst) | no, not an FP emulation Ldofp_unimp: #ifdef FPSP jmp _ASM_LABEL(fpsp_unimp) | yes, go handle it #endif Lfp_unimp: #endif /* M68040 */ #ifdef FPU_EMULATE clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- | save registers moveq #T_FPEMULI,%d0 | denote as FP emulation trap jra _ASM_LABEL(fault) | do it #else jra _C_LABEL(illinst) #endif ENTRY_NOPROFILE(fpunsupp) #if defined(M68040) cmpl #FPU_68040,_C_LABEL(fputype) | 68040 FPU? jne _C_LABEL(illinst) | no, treat as illinst #ifdef FPSP jmp _ASM_LABEL(fpsp_unsupp) | yes, go handle it #endif Lfp_unsupp: #endif /* M68040 */ #ifdef FPU_EMULATE clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- | save registers moveq #T_FPEMULD,%d0 | denote as FP emulation trap jra _ASM_LABEL(fault) | do it #else jra _C_LABEL(illinst) #endif /* * Handles all other FP coprocessor exceptions. * Note that since some FP exceptions generate mid-instruction frames * and may cause signal delivery, we need to test for stack adjustment * after the trap call. */ ENTRY_NOPROFILE(fpfault) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- | save user registers movl %usp,%a0 | and save movl %a0,%sp@(FR_SP) | the user stack pointer clrl %sp@- | no VA arg movl _C_LABEL(curpcb),%a0 | current pcb lea %a0@(PCB_FPCTX),%a0 | address of FP savearea fsave %a0@ | save state #if defined(M68040) || defined(M68060) /* always null state frame on 68040, 68060 */ cmpl #FPU_68040,_C_LABEL(fputype) jge Lfptnull #endif tstb %a0@ | null state frame? jeq Lfptnull | yes, safe clrw %d0 | no, need to tweak BIU movb %a0@(1),%d0 | get frame size bset #3,%a0@(0,%d0:w) | set exc_pend bit of BIU Lfptnull: fmovem %fpsr,%sp@- | push %fpsr as code argument frestore %a0@ | restore state movl #T_FPERR,%sp@- | push type arg jra _ASM_LABEL(faultstkadj) | call trap and deal with stack cleanup /* * Other exceptions only cause four and six word stack frame and require * no post-trap stack adjustment. */ ENTRY_NOPROFILE(badtrap) moveml #0xC0C0,%sp@- | save scratch regs movw %sp@(22),%sp@- | push exception vector info clrw %sp@- movl %sp@(22),%sp@- | and PC jbsr _C_LABEL(straytrap) | report addql #8,%sp | pop args moveml %sp@+,#0x0303 | restore regs jra _ASM_LABEL(rei) | all done ENTRY_NOPROFILE(trap0) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- | save user registers movl %usp,%a0 | save the user SP movl %a0,%sp@(FR_SP) | in the savearea movl %d0,%sp@- | push syscall number jbsr _C_LABEL(syscall) | handle it addql #4,%sp | pop syscall arg tstl _C_LABEL(astpending) | AST pending? jne Lrei | yes, handle it via trap movl %sp@(FR_SP),%a0 | grab and restore movl %a0,%usp | user SP moveml %sp@+,#0x7FFF | restore most registers addql #8,%sp | pop SP and stack adjust rte /* * Trap 12 is the entry point for the cachectl "syscall" (both HPUX & BSD) * cachectl(command, addr, length) * command in %d0, addr in %a1, length in %d1 */ ENTRY_NOPROFILE(trap12) movl _C_LABEL(curlwp),%a0 movl %a0@(L_PROC),%sp@- | push current proc pointer movl %d1,%sp@- | push length movl %a1,%sp@- | push addr movl %d0,%sp@- | push command jbsr _C_LABEL(cachectl1) | do it lea %sp@(16),%sp | pop args jra _ASM_LABEL(rei) | all done /* * Trace (single-step) trap. Kernel-mode is special. * User mode traps are simply passed on to trap(). */ ENTRY_NOPROFILE(trace) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- moveq #T_TRACE,%d0 | Check PSW and see what happen. | T=0 S=0 (should not happen) | T=1 S=0 trace trap from user mode | T=0 S=1 trace trap on a trap instruction | T=1 S=1 trace trap from system mode (kernel breakpoint) movw %sp@(FR_HW),%d1 | get PSW notw %d1 | XXX no support for T0 on 680[234]0 andw #PSL_TS,%d1 | from system mode (T=1, S=1)? jeq Lkbrkpt | yes, kernel breakpoint jra _ASM_LABEL(fault) | no, user-mode fault /* * Trap 15 is used for: * - GDB breakpoints (in user programs) * - KGDB breakpoints (in the kernel) * - trace traps for SUN binaries (not fully supported yet) * User mode traps are simply passed to trap(). */ ENTRY_NOPROFILE(trap15) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- moveq #T_TRAP15,%d0 movw %sp@(FR_HW),%d1 | get PSW andw #PSL_S,%d1 | from system mode? jne Lkbrkpt | yes, kernel breakpoint jra _ASM_LABEL(fault) | no, user-mode fault Lkbrkpt: | Kernel-mode breakpoint or trace trap. (%d0=trap_type) | Save the system sp rather than the user sp. movw #PSL_HIGHIPL,%sr | lock out interrupts lea %sp@(FR_SIZE),%a6 | Save stack pointer movl %a6,%sp@(FR_SP) | from before trap | If were are not on tmpstk switch to it. | (so debugger can change the stack pointer) movl %a6,%d1 cmpl #_ASM_LABEL(tmpstk),%d1 jls Lbrkpt2 | already on tmpstk | Copy frame to the temporary stack movl %sp,%a0 | %a0=src lea _ASM_LABEL(tmpstk)-96,%a1 | %a1=dst movl %a1,%sp | %sp=new frame moveq #FR_SIZE,%d1 Lbrkpt1: movl %a0@+,%a1@+ subql #4,%d1 jgt Lbrkpt1 Lbrkpt2: | Call the trap handler for the kernel debugger. | Do not call trap() to do it, so that we can | set breakpoints in trap() if we want. We know | the trap type is either T_TRACE or T_BREAKPOINT. | If we have both DDB and KGDB, let KGDB see it first, | because KGDB will just return 0 if not connected. | Save args in %d2, %a2 movl %d0,%d2 | trap type movl %sp,%a2 | frame ptr #ifdef KGDB | Let KGDB handle it (if connected) movl %a2,%sp@- | push frame ptr movl %d2,%sp@- | push trap type jbsr _C_LABEL(kgdb_trap) | handle the trap addql #8,%sp | pop args cmpl #0,%d0 | did kgdb handle it? jne Lbrkpt3 | yes, done #endif #ifdef DDB | Let DDB handle it movl %a2,%sp@- | push frame ptr movl %d2,%sp@- | push trap type jbsr _C_LABEL(kdb_trap) | handle the trap addql #8,%sp | pop args #if 0 /* not needed on hp300 */ cmpl #0,%d0 | did ddb handle it? jne Lbrkpt3 | yes, done #endif #endif /* Sun 3 drops into PROM here. */ Lbrkpt3: | The stack pointer may have been modified, or | data below it modified (by kgdb push call), | so push the hardware frame at the current sp | before restoring registers and returning. movl %sp@(FR_SP),%a0 | modified %sp lea %sp@(FR_SIZE),%a1 | end of our frame movl %a1@-,%a0@- | copy 2 longs with movl %a1@-,%a0@- | ... predecrement movl %a0,%sp@(FR_SP) | %sp = h/w frame moveml %sp@+,#0x7FFF | restore all but %sp movl %sp@,%sp | ... and %sp rte | all done /* * Interrupt handlers. */ ENTRY_NOPROFILE(lev7intr) /* Level 7: NMI */ addql #1,_C_LABEL(m68k_intr_evcnt)+NMI_INTRCNT clrl %sp@- moveml #0xFFFF,%sp@- | save registers movl %usp,%a0 | and save movl %a0,%sp@(FR_SP) | the user stack pointer jbsr _C_LABEL(nmihand) | call handler movl %sp@(FR_SP),%a0 | restore movl %a0,%usp | user SP moveml %sp@+,#0x7FFF | and remaining registers addql #8,%sp | pop SP and stack adjust jra _ASM_LABEL(rei) | all done #if 1 /* XXX wild timer -- how can I disable/enable the interrupt? */ ENTRY_NOPROFILE(lev5intr) addql #1,_C_LABEL(intr_depth) btst #7,OBIO_CLOCK | check whether system clock beq 2f movb #1,OBIO_CLOCK | clear the interrupt tstl _C_LABEL(clock_enable) | is hardclock() available? jeq 1f INTERRUPT_SAVEREG lea %sp@(0),%a1 | %a1 = &clockframe movl %a1,%sp@- jbsr _C_LABEL(hardclock) | hardclock(&frame) addql #4,%sp addql #1,_C_LABEL(m68k_intr_evcnt)+CLOCK_INTRCNT INTERRUPT_RESTOREREG 1: subql #1,_C_LABEL(intr_depth) jra _ASM_LABEL(rei) | all done 2: | XP device has also lev5 intr, | routing to autovec subql #1,_C_LABEL(intr_depth) jbra _C_LABEL(intrstub_autovec) #endif /* * Emulation of VAX REI instruction. * * This code deals with checking for and servicing ASTs * (profiling, scheduling) and software interrupts (network, softclock). * We check for ASTs first, just like the VAX. To avoid excess overhead * the T_ASTFLT handling code will also check for software interrupts so we * do not have to do it here. After identifying that we need an AST we * drop the IPL to allow device interrupts. * * This code is complicated by the fact that sendsig may have been called * necessitating a stack cleanup. */ ASENTRY_NOPROFILE(rei) tstl _C_LABEL(astpending) | AST pending? jne 1f | no, done rte 1: btst #5,%sp@ | yes, are we returning to user mode? jeq 2f | no, done rte 2: movw #PSL_LOWIPL,%sr | lower SPL clrl %sp@- | stack adjust moveml #0xFFFF,%sp@- | save all registers movl %usp,%a1 | including movl %a1,%sp@(FR_SP) | the users SP Lrei: clrl %sp@- | VA == none clrl %sp@- | code == none movl #T_ASTFLT,%sp@- | type == async system trap pea %sp@(12) | fp == address of trap frame jbsr _C_LABEL(trap) | go handle it lea %sp@(16),%sp | pop value args movl %sp@(FR_SP),%a0 | restore user SP movl %a0,%usp | from save area movw %sp@(FR_ADJ),%d0 | need to adjust stack? jne Laststkadj | yes, go to it moveml %sp@+,#0x7FFF | no, restore most user regs addql #8,%sp | toss SP and stack adjust rte | and do real RTE Laststkadj: lea %sp@(FR_HW),%a1 | pointer to HW frame addql #8,%a1 | source pointer movl %a1,%a0 | source addw %d0,%a0 | + hole size = dest pointer movl %a1@-,%a0@- | copy movl %a1@-,%a0@- | 8 bytes movl %a0,%sp@(FR_SP) | new SSP moveml %sp@+,#0x7FFF | restore user registers movl %sp@,%sp | and our SP rte | and do real RTE /* * Primitives */ /* * Use common m68k process/lwp switch and context save subroutines. */ #define FPCOPROC /* XXX: Temp. reqd. */ #include #if defined(M68040) ENTRY(suline) movl %sp@(4),%a0 | address to write movl _C_LABEL(curpcb),%a1 | current pcb movl #Lslerr,%a1@(PCB_ONFAULT) | where to return to on a fault movl %sp@(8),%a1 | address of line movl %a1@+,%d0 | get lword movsl %d0,%a0@+ | put lword nop | sync movl %a1@+,%d0 | get lword movsl %d0,%a0@+ | put lword nop | sync movl %a1@+,%d0 | get lword movsl %d0,%a0@+ | put lword nop | sync movl %a1@+,%d0 | get lword movsl %d0,%a0@+ | put lword nop | sync moveq #0,%d0 | indicate no fault jra Lsldone Lslerr: moveq #-1,%d0 Lsldone: movl _C_LABEL(curpcb),%a1 | current pcb clrl %a1@(PCB_ONFAULT) | clear fault address rts #endif ENTRY(ecacheon) rts ENTRY(ecacheoff) rts /* * _delay(u_int N) * * Delay for at least (N/256) microseconds. * This routine depends on the variable: delay_divisor * which should be set based on the CPU clock rate. */ ENTRY_NOPROFILE(_delay) | %d0 = arg = (usecs << 8) movl %sp@(4),%d0 | %d1 = delay_divisor movl _C_LABEL(delay_divisor),%d1 jra L_delay /* Jump into the loop! */ /* * Align the branch target of the loop to a half-line (8-byte) * boundary to minimize cache effects. This guarantees both * that there will be no prefetch stalls due to cache line burst * operations and that the loop will run from a single cache * half-line. */ .align 8 L_delay: subl %d1,%d0 jgt L_delay rts /* * Do a dump. * Called by auto-restart. */ GLOBAL(doadump) jbsr _C_LABEL(dumpsys) jbsr _C_LABEL(doboot) /*NOTREACHED*/ /* * Handle the nitty-gritty of rebooting the machine. * Basically we just turn off the MMU, restore the initial %vbr * and return to monitor. */ ENTRY_NOPROFILE(doboot) movw #PSL_HIGHIPL,%sr | no interrupts movl _C_LABEL(boothowto),%d7 | load howto movl %sp@(4),%d2 | arg #if defined(M68040) cmpl #MMU_68040,_C_LABEL(mmutype) | 68040? jeq Lnocache5 | yes, skip #endif movl #CACHE_OFF,%d0 movc %d0,%cacr | disable on-chip cache(s) movl #0,%a7@ | value for pmove to %tc pmove %a7@,%tc | disable MMU lea _ASM_LABEL(nullrp),%a0 pmove %a0@,%crp | Invalidate CPU root pointer pmove %a0@,%srp | and the Supervisor root pointer jra Lbootcommon #if defined(M68040) Lnocache5: .word 0xf4f8 | cpusha bc movql #0,%d0 movc %d0,%cacr .long 0x4e7b0003 | movc %d0,%tc (disable MMU) .long 0x4e7b0806 | movc %d0,%urp .long 0x4e7b0807 | movc %d0,%srp #endif /* M68040 */ Lbootcommon: lea _ASM_LABEL(tmpstk),%sp | physical SP in case of NMI movl #0,%d3 movc %d3,%vbr | monitor %vbr movl #PROM_ADDR,%a0 | base = (int **)0x4100.0000 movl %a0@,%d0 | *((int *)base[0]) movc %d0,%isp | set initial stack pointer movc %d0,%msp | set initial stack pointer movl %a0@(4),%a0 | *((int (*)(void))base[1]) jmp %a0@ | go cold boot! .data GLOBAL(cputype) .long CPU_68030 | default to 68030 GLOBAL(mmutype) .long MMU_68030 | default to 68030 GLOBAL(fputype) .long FPU_68881 | default to 68881 GLOBAL(prototc) .long MMU51_TCR_BITS | %tc -- see pmap.h GLOBAL(protott0) .long LUNA68K_TT30_IO0 | prototype transparent translation register 0 GLOBAL(protott1) .long LUNA68K_TT30_IO1 | prototype transparent translation register 1 GLOBAL(proto040tc) .long MMU40_TCR_BITS | %tc -- see pmap.h GLOBAL(proto040tt0) .long LUNA68K_TT40_IO0 | prototype transparent translation register 0 GLOBAL(proto040tt1) .long LUNA68K_TT40_IO1 | prototype transparent translation register 1 nullrp: .long 0x7fff0001 | do-nothing MMU root pointer GLOBAL(memavail) .long 0 GLOBAL(bootdev) .long 0 GLOBAL(hwplanemask) .long 0 GLOBAL(bootarg) .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 #ifdef DEBUG ASGLOBAL(fulltflush) .long 0 ASGLOBAL(fullcflush) .long 0 #endif GLOBAL(intiobase) .long 0 | KVA of base of internal IO space GLOBAL(intiolimit) .long 0 | KVA of end of internal IO space GLOBAL(intiobase_phys) .long 0 | PA of board's I/O registers GLOBAL(intiotop_phys) .long 0 | PA of top of board's I/O registers