/* $NetBSD: locore.s,v 1.85 2024/01/17 12:33:50 thorpej Exp $ */ /* * Copyright (c) 1998 Darrin B. Jewell * 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 */ /* * Copyright (c) 1994, 1995 Gordon W. Ross * Copyright (c) 1988 University of Utah. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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 */ /* This is currently amid development by * Darrin Jewell Fri Jan 2 14:36:47 1998 * for the next68k port */ #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_useleds.h" #include "opt_m68k_arch.h" #include "assym.h" #include #include #if (!defined(M68040)) #error "M68040 is not defined! (check that the generated assym.h is not empty)" #endif #include "ksyms.h" /* * 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) /* * Leave page zero empty so it can be unmapped */ .space PAGE_SIZE /* * Temporary stack for a variety of purposes. */ .data GLOBAL(endstack) .space PAGE_SIZE GLOBAL(bgnstack) ASLOCAL(tmpstk) /* * Macro to relocate a symbol, used before MMU is enabled. * On the NeXT, memory is laid out as in the mach header * so therefore we need to relocate symbols until the MMU * is turned on. */ #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) /* * Initialization info as per grossman's boot loader: * * We are called from the boot prom, not the boot loader. We have the * prom's stack initialized for us and we were called like this: * start(mg, mg->mg_console_i, mg->mg_console_o, * mg->mg_boot_dev, mg->mg_boot_arg, mg->mg_boot_info, * mg->mg_sid, mg->mg_pagesize, 4, mg->mg_region, * etheraddr, mg->mg_boot_file); * so we actually only really need the first parameter from the stack. * Exceptions will be handled by the prom until we feel ready to handle * them ourselves. * By the way, we get loaded at our final address i.e. PA==VA for the kernel. */ /* I think the PA==VA comment to be a lie, but I have yet to verify it. * Darrin B Jewell Sun Jan 11 01:05:54 1998 */ BSS(lowram,4) BSS(esym,4) ASENTRY_NOPROFILE(start) movw #PSL_HIGHIPL,%sr | no interrupts movl #CACHE_OFF,%d0 movc %d0,%cacr | clear and disable on-chip cache(s) moveal #NEXT_RAMBASE,%a5 | amount to RELOC by. RELOC(lowram,%a0) | store base of memory. movl %a5,%a0@ | Create a new stack at address tmpstk, and push | The existing sp onto it as an arg for next68k_bootargs. ASRELOC(tmpstk, %a0) movel %sp,%a0@- moveal %a0,%sp moveal #0,%a6 /* Read the header to get our segment list */ RELOC(next68k_bootargs,%a0) jbsr %a0@ | next68k_bootargs(args) addqw #4,%sp | clear arg from stack. /* * All data registers are now free. All address registers * except %a5 are free. %a5 is used by the RELOC() macro on hp300 * and cannot be used until after the MMU is enabled. */ /* determine our CPU/MMU combo - check for all regardless of kernel config */ movl #0x200,%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 68020/68040 /* * 68030 models */ RELOC(mmutype, %a0) | no, we have 68030 movl #MMU_68030,%a0@ | set to reflect 68030 PMMU RELOC(cputype, %a0) movl #CPU_68030,%a0@ | and 68030 CPU RELOC(machineid, %a0) movl #30,%a0@ | @@@ useless jra Lstart1 /* * End of 68030 section */ Lnot68030: bset #31,%d0 | data cache enable bit movc %d0,%cacr | only exists on 68040 movc %cacr,%d0 | read it back tstl %d0 | zero? beq Lis68020 | yes, we have 68020 moveq #0,%d0 | now turn it back off movec %d0,%cacr | before we access any data /* * 68040 models */ RELOC(mmutype, %a0) movl #MMU_68040,%a0@ | with a 68040 MMU RELOC(cputype, %a0) movl #CPU_68040,%a0@ | and a 68040 CPU RELOC(fputype, %a0) movl #FPU_68040,%a0@ | ...and FPU RELOC(machineid, %a0) movl #40,%a0@ | @@@ useless jra Lstart1 /* * End of 68040 section */ /* * 68020 models * (There are no 68020 models of NeXT, but we'll pretend) */ Lis68020: RELOC(mmutype, %a0) movl #MMU_68851,%a0@ | no, we have PMMU RELOC(fputype, %a0) | all of the 68020 systems movl #FPU_68881,%a0@ | have a 68881 FPU RELOC(cputype, %a0) movl #CPU_68020,%a0@ | and a 68020 CPU RELOC(machineid, %a0) movl #20,%a0@ | @@@ useless jra Lstart1 /* * End of 68020 section */ Lstart1: /* 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 /* 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@,%d5 jne Lstart3 #endif movl #_C_LABEL(end),%d5 | end of static kernel text/data Lstart3: addl #PAGE_SIZE-1,%d5 andl #PG_FRAME,%d5 | round to a page movl %d5,%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 /* * Prepare to enable MMU. * Since the kernel is not mapped logical == physical we must insure * that when the MMU is turned on, all prefetched addresses (including * the PC) are valid. In order guarantee that, we use the transparent * translation registers (which provide PA == VA mappings) and just * turns on the MMU, then jump from the VA == PA address (at 0x40XXXXXX) * to the actual kernel virtual address (at 0x00XXXXXX) code via a far * jump instruction so that we can defeat the prefetch. */ RELOC(Sysseg_pa, %a0) | system segment table addr movl %a0@,%d1 | read value (a PA) RELOC(mmutype, %a0) cmpl #MMU_68040,%a0@ | 68040? jne Lmotommu1 | no, skip .long 0x4e7b1807 | movc %d1,%srp jra Lstploaddone Lmotommu1: #ifdef M68030 RELOC(protorp, %a0) movl %d1,%a0@(4) | segtable address pmove %a0@,%srp | load the supervisor root pointer #endif /* M68030 */ Lstploaddone: RELOC(mmutype, %a0) cmpl #MMU_68040,%a0@ | 68040? jne Lmotommu2 | no, skip | This is a hack to get PA=KVA when turning on MMU as mentioned above. | Currently this will only work on 68040's. We should also provide | %tt0 and %tt1 settings to boot 68030's later. movel #NEXT68K_TT40_IO,%d0 | see pmap.h .long 0x4e7b0004 | movc %d0,%itt0 .long 0x4e7b0006 | movc %d0,%dtt0 movel #NEXT68K_TT40_KERN,%d0 | see pmap.h .long 0x4e7b0005 | movc %d0,%itt1 .long 0x4e7b0007 | movc %d0,%dtt1 .word 0xf4d8 | cinva bc .word 0xf518 | pflusha movl #MMU40_TCR_BITS,%d0 .long 0x4e7b0003 | movc %d0,%tc movl #0x80008000,%d0 movc %d0,%cacr | turn on both caches jmp Lturnoffttr:l | global jump into mapped memory. Lturnoffttr: moveq #0,%d0 | ensure TT regs are disabled .long 0x4e7b0004 | movc %d0,%itt0 .long 0x4e7b0006 | movc %d0,%dtt0 .long 0x4e7b0005 | movc %d0,%itt1 .long 0x4e7b0007 | movc %d0,%dtt1 jmp Lenab1 Lmotommu2: pflusha RELOC(prototc, %a2) movl #MMU51_TCR_BITS,%a2@ | value to load TC with pmove %a2@,%tc | load it jmp Lenab1:l | force absolute (not pc-relative) jmp /* * 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 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: cmpl #MMU_68040,_C_LABEL(mmutype) | 68040? jeq Ltbia040 | yes, cache already on pflusha movl #CACHE_ON,%d0 movc %d0,%cacr | clear cache(s) jra Lenab3 Ltbia040: .word 0xf518 | pflusha Lenab3: jbsr _C_LABEL(next68k_init) /* Final setup for call to main(). */ /* * Create a fake exception frame so that cpu_lwp_fork() can copy it. * main() nevers returns; we exit to user mode from a forked process * later on. */ 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.p_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) jne Lrei 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 curproc 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 bgt 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. * * For auto-vectored interrupts, the CPU provides the * vector 0x18+level. Note we count spurious interrupts, * but don't do anything else with them. * * intrhand_autovec is the entry point for auto-vectored * interrupts. * * For vectored interrupts, we pull the pc, evec, and exception frame * and pass them to the vectored interrupt dispatcher. The vectored * interrupt dispatcher will deal with strays. */ ENTRY_NOPROFILE(lev7intr) /* level 7: parity errors, reset key */ 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 /* * 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 /* * _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 /* * Handle the nitty-gritty of rebooting the machine. * Basically we just turn off the MMU and jump to the appropriate ROM routine. * Note that we must be running in an address range that is mapped one-to-one * logical to physical so that the PC is still valid immediately after the MMU * is turned off. We have conveniently mapped the last page of physical * memory this way. */ ENTRY_NOPROFILE(doboot) movw #PSL_HIGHIPL,%sr | no interrupts movl #CACHE_OFF,%d0 movc %d0,%cacr | clear and disable on-chip cache(s) | Turn on physical memory mapping. | @@@ This is also 68040 specific and needs fixing. movel #0x0200c040,%d0 | intio devices are at 0x02000000 .long 0x4e7b0004 | movc %d0,%itt0 .long 0x4e7b0006 | movc %d0,%dtt0 movel #0x0403c000,%d0 | kernel text and data at 0x04000000 .long 0x4e7b0005 | movc %d0,%itt1 .long 0x4e7b0007 | movc %d0,%dtt1 moveal #NEXT_RAMBASE,%a5 | amount to RELOC by. | Create a new stack at address tmpstk, and push | The existing sp onto it for kicks. ASRELOC(tmpstk, %a0) movel %sp,%a0@- moveal %a0,%sp moveal #0,%a6 ASRELOC(Ldoboot1, %a0) jmp %a0@ | jump into physical address space. Ldoboot1: RELOC(saved_vbr, %a0) movl %a0@,%d0 movc %d0,%vbr | reset the registers as the boot rom likes them: movel #0x0200c040,%d0 | .long 0x4e7b0004 | movc %d0,%itt0 .long 0x4e7b0006 | movc %d0,%dtt0 movel #0x00ffc000,%d0 | .long 0x4e7b0005 | movc %d0,%itt1 .long 0x4e7b0007 | movc %d0,%dtt1 RELOC(monbootflag, %a0) movel %a0,%d0 | "-h" halts instead of reboot. trap #13 hloop: bra hloop | This shouldn't be reached. /* * Misc. global variables. */ .data GLOBAL(machineid) .long 0xdeadbeef | default to @@@ GLOBAL(mmuid) .long 0 | default to nothing GLOBAL(mmutype) .long 0xdeadbeef | default to 68040 mmu GLOBAL(cputype) .long 0xdeadbeef | default to 68020 CPU GLOBAL(fputype) .long 0xdeadbeef | default to 68882 FPU GLOBAL(prototc) .long 0 | prototype translation control GLOBAL(intiobase) .long INTIOBASE | KVA of base of internal IO space GLOBAL(intiolimit) .long INTIOTOP | KVA of end of internal IO space GLOBAL(fbbase) .long 0 | KVA of base of framebuffer GLOBAL(fblimit) .long 0 | KVA of end of framebuffer GLOBAL(fbbasepa) .long MONOBASE | PA of base of framebuffer GLOBAL(fblimitpa) .long MONOTOP | PA of end of framebuffer GLOBAL(monbootflag) .long 0 #ifdef USELEDS ASLOCAL(heartbeat) .long 0 | clock ticks since last pulse of heartbeat ASLOCAL(beatstatus) .long 0 | for determining a fast or slow throb #endif #ifdef DEBUG ASGLOBAL(fulltflush) .long 0 ASGLOBAL(fullcflush) .long 0 #endif