/* $NetBSD: locore.s,v 1.69.4.1 2024/06/27 19:27:28 martin 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_kgdb.h" #include "opt_lockdebug.h" #include "assym.h" #include #include | Remember this is a fun project! .data GLOBAL(mon_crp) .long 0,0 | 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) | This is the entry point, as well as the end of the temporary stack | used during process switch (one 8K page ending at start) ASGLOBAL(tmpstk) ASGLOBAL(start) | The first step, after disabling interrupts, is to map enough of the kernel | into high virtual address space so that we can use position dependent code. | This is a tricky task on the sun3x because the MMU is already enabled and | the ROM monitor provides no indication of where the root MMU table is mapped. | Therefore we must use one of the 68030's 'transparent translation' registers | to define a range in the address space where the MMU translation is | turned off. Once this is complete we can modify the MMU table directly | without the need for it to be mapped into virtual memory. | All code must be position independent until otherwise noted, as the | boot loader has loaded us into low memory but all the symbols in this | code have been linked high. movw #PSL_HIGHIPL,%sr | no interrupts movl #KERNBASE3X,%a5 | for vtop conversion lea _C_LABEL(mon_crp),%a0 | where to store the CRP subl %a5,%a0 | Note: borrowing mon_crp for tt0 setup... movl #0x3F8107,%a0@ | map the low 1GB v=p with the .long 0xf0100800 | transparent translation reg0 | [ pmove a0@, tt0 ] | In order to map the kernel into high memory we will copy the root table | entry which maps the 16 megabytes of memory starting at 0x0 into the | entry which maps the 16 megabytes starting at KERNBASE. pmove %crp,%a0@ | Get monitor CPU root pointer movl %a0@(4),%a1 | 2nd word is PA of level A table movl %a1,%a0 | compute the descriptor address addl #0x3e0,%a1 | for VA starting at KERNBASE movl %a0@,%a1@ | copy descriptor type movl %a0@(4),%a1@(4) | copy physical address | Kernel is now double mapped at zero and KERNBASE. | Force a long jump to the relocated code (high VA). movl #IC_CLEAR,%d0 | Flush the I-cache movc %d0,%cacr jmp L_high_code:l | long jump L_high_code: | We are now running in the correctly relocated kernel, so | we are no longer restricted to position-independent code. | It is handy to leave transparent translation enabled while | for the low 1GB while _bootstrap() is doing its thing. | Do bootstrap stuff needed before main() gets called. | Our boot loader leaves a copy of the kernel's exec header | just before the start of the kernel text segment, so the | kernel can sanity-check the DDB symbols at [end...esym]. | Pass the struct exec at tmpstk-32 to _bootstrap(). | Also, make sure the initial frame pointer is zero so that | the backtrace algorithm used by KGDB terminates nicely. lea _ASM_LABEL(tmpstk)-32,%sp movl #0,%a6 jsr _C_LABEL(_bootstrap) | See locore2.c | Now turn off the transparent translation of the low 1GB. | (this also flushes the ATC) clrl %sp@- .long 0xf0170800 | pmove sp@,tt0 addql #4,%sp | Now that _bootstrap() is done using the PROM functions, | we can safely set the sfc/dfc to something != FC_CONTROL moveq #FC_USERD,%d0 | make movs access "user data" movc %d0,%sfc | space for copyin/copyout movc %d0,%dfc | Setup process zero user/kernel stacks. lea _C_LABEL(lwp0),%a0 | get lwp0 movl %a0@(L_PCB),%a1 | XXXuvm_lwp_getuarea lea %a1@(USPACE-4),%sp | set SSP to last word movl #USRSTACK3X-4,%a2 movl %a2,%usp | init user SP | Note curpcb was already set in _bootstrap(). | Will do fpu initialization during autoconfig (see fpu.c) | The interrupt vector table and stack are now ready. | Interrupts will be enabled later, AFTER autoconfiguration | is finished, to avoid spurrious interrupts. /* * 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@- | tf_format,tf_vector clrl %sp@- | tf_pc (filled in later) movw #PSL_USER,%sp@- | tf_sr for user mode clrl %sp@- | tf_stackadj lea %sp@(-64),%sp | tf_regs[16] movl %a1,%a0@(L_MD_REGS) | lwp0.l_md.md_regs = trapframe jbsr _C_LABEL(main) | main(&trapframe) PANIC("main() returned") | That is all the assembly startup code we need on the sun3x! | The rest of this is like the hp300/locore.s where possible. /* * Trap/interrupt vector routines */ #include GLOBAL(buserr) tstl _C_LABEL(nofault) | device probe? jeq _C_LABEL(addrerr) | no, handle as usual movl _C_LABEL(nofault),%sp@- | yes, jbsr _C_LABEL(longjmp) | longjmp(nofault) GLOBAL(addrerr) 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 lea %sp@(FR_HW),%a1 | grab base of HW berr frame moveq #0,%d0 movw %a1@(10),%d0 | grab SSW for fault processing btst #12,%d0 | RB set? jeq LbeX0 | no, test RC bset #14,%d0 | yes, must set FB movw %d0,%a1@(10) | for hardware too LbeX0: btst #13,%d0 | RC set? jeq LbeX1 | no, skip bset #15,%d0 | yes, must set FC movw %d0,%a1@(10) | for hardware too LbeX1: btst #8,%d0 | data fault? jeq Lbe0 | no, check for hard cases movl %a1@(16),%d1 | fault address is as given in frame jra Lbe10 | thats it Lbe0: btst #4,%a1@(6) | long (type B) stack frame? jne Lbe4 | yes, go handle movl %a1@(2),%d1 | no, can use save PC btst #14,%d0 | FB set? jeq Lbe3 | no, try FC addql #4,%d1 | yes, adjust address jra Lbe10 | done Lbe3: btst #15,%d0 | FC set? jeq Lbe10 | no, done addql #2,%d1 | yes, adjust address jra Lbe10 | done Lbe4: movl %a1@(36),%d1 | long format, use stage B address btst #15,%d0 | FC set? jeq Lbe10 | no, all done subql #2,%d1 | yes, adjust address Lbe10: movl %d1,%sp@- | push fault VA movl %d0,%sp@- | and padded SSW movw %a1@(6),%d0 | get frame format/vector offset andw #0x0FFF,%d0 | clear out frame format cmpw #12,%d0 | address error vector? jeq Lisaerr | yes, go to it /* MMU-specific code to determine reason for bus error. */ movl %d1,%a0 | fault address movl %sp@,%d0 | function code from ssw btst #8,%d0 | data fault? jne Lbe10a movql #1,%d0 | user program access FC | (we dont separate data/program) btst #5,%a1@ | supervisor mode? jeq Lbe10a | if no, done movql #5,%d0 | else supervisor program access Lbe10a: ptestr %d0,%a0@,#7 | do a table search pmove %psr,%sp@ | save result movb %sp@,%d1 btst #2,%d1 | invalid? (incl. limit viol and berr) jeq Lmightnotbemerr | no -> wp check btst #7,%d1 | is it MMU table berr? jeq Lismerr | no, must be fast jra Lisberr1 | real bus err needs not be fast Lmightnotbemerr: btst #3,%d1 | write protect bit set? jeq Lisberr1 | no, must be bus error movl %sp@,%d0 | ssw into low word of d0 andw #0xc0,%d0 | write protect is set on page: cmpw #0x40,%d0 | was it read cycle? jeq Lisberr1 | yes, was not WPE, must be bus err /* End of MMU-specific bus error code. */ Lismerr: movl #T_MMUFLT,%sp@- | show that we are an MMU fault jra _ASM_LABEL(faultstkadj) | and deal with it Lisaerr: movl #T_ADDRERR,%sp@- | mark address error jra _ASM_LABEL(faultstkadj) | and deal with it Lisberr1: clrw %sp@ | re-clear pad word Lisberr: movl #T_BUSERR,%sp@- | mark bus error jra _ASM_LABEL(faultstkadj) | and deal with it /* * FP exceptions. */ GLOBAL(fpfline) 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 GLOBAL(fpunsupp) 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 /* * 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. */ GLOBAL(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 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. */ GLOBAL(badtrap) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- | save std frame regs jbsr _C_LABEL(straytrap) | report moveml %sp@+,#0xFFFF | restore regs addql #4,%sp | stack adjust count jra _ASM_LABEL(rei) | all done /* * Trap 0 is for system calls */ GLOBAL(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 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 jra _ASM_LABEL(rei) | all done /* * Trap 12 is the entry point for the cachectl "syscall" * cachectl(command, addr, length) * command in d0, addr in a1, length in d1 */ GLOBAL(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(). */ GLOBAL(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 _ASM_LABEL(kbrkpt) | yes, kernel brkpt 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(). */ GLOBAL(trap15) clrl %sp@- | stack adjust count moveml #0xFFFF,%sp@- moveq #T_TRAP15,%d0 btst #5,%sp@(FR_HW) | was supervisor mode? jne _ASM_LABEL(kbrkpt) | yes, kernel brkpt jra _ASM_LABEL(fault) | no, user-mode fault ASLOCAL(kbrkpt) | 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 we 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 handle it, so that we can | set breakpoints in trap() if we want. We know | the trap type is either T_TRACE or T_BREAKPOINT. movl %d0,%sp@- | push trap type jbsr _C_LABEL(trap_kdebug) addql #4,%sp | pop args | 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. Most are auto-vectored, * and hard-wired the same way on all sun3 models. * Format in the stack is: * %d0,%d1,%a0,%a1, sr, pc, vo */ /* * This is the common auto-vector interrupt handler, * for which the CPU provides the vector=0x18+level. * These are installed in the interrupt vector table. */ #ifdef __ELF__ .align 4 #else .align 2 #endif GLOBAL(_isr_autovec) INTERRUPT_SAVEREG jbsr _C_LABEL(isr_autovec) INTERRUPT_RESTOREREG jra _ASM_LABEL(rei) /* clock: see clock.c */ #ifdef __ELF__ .align 4 #else .align 2 #endif GLOBAL(_isr_clock) INTERRUPT_SAVEREG jbsr _C_LABEL(clock_intr) INTERRUPT_RESTOREREG jra _ASM_LABEL(rei) | Handler for all vectored interrupts (i.e. VME interrupts) #ifdef __ELF__ .align 4 #else .align 2 #endif GLOBAL(_isr_vectored) INTERRUPT_SAVEREG jbsr _C_LABEL(isr_vectored) INTERRUPT_RESTOREREG jra _ASM_LABEL(rei) /* interrupt counters (needed by vmstat) */ GLOBAL(intrnames) .asciz "spur" | 0 .asciz "lev1" | 1 .asciz "lev2" | 2 .asciz "lev3" | 3 .asciz "lev4" | 4 .asciz "clock" | 5 .asciz "lev6" | 6 .asciz "nmi" | 7 GLOBAL(eintrnames) .data .even GLOBAL(intrcnt) .long 0,0,0,0,0,0,0,0 GLOBAL(eintrcnt) .text /* * Emulation of VAX REI instruction. * * This code is (mostly) un-altered from the hp300 code, * except that sun machines do not need a simulated SIR * because they have a real software interrupt register. * * 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. */ ASGLOBAL(rei) #ifdef DIAGNOSTIC tstl _C_LABEL(panicstr) | have we panicked? jne Ldorte | yes, do not make matters worse #endif tstl _C_LABEL(astpending) | AST pending? jeq Ldorte | no, done Lrei1: btst #5,%sp@ | yes, are we returning to user mode? jne Ldorte | no, done 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 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 Ldorte: rte | real return /* * Initialization is at the beginning of this file, because the * kernel entry point needs to be at zero for compatibility with * the Sun boot loader. This works on Sun machines because the * interrupt vector table for reset is NOT at address zero. * (The MMU has a "boot" bit that forces access to the PROM) */ /* * Use common m68k sigcode. */ #include #ifdef COMPAT_SUNOS #include #endif .text /* * Primitives */ /* * Use common m68k support routines. */ #include /* * Use common m68k process/lwp switch and context save subroutines. */ #define FPCOPROC /* XXX: Temp. Reqd. */ #include /* suline() */ #ifdef DEBUG .data ASGLOBAL(fulltflush) .long 0 ASGLOBAL(fullcflush) .long 0 .text #endif ENTRY(ecacheon) rts ENTRY(ecacheoff) rts /* * Get callers current SP value. * Note that simply taking the address of a local variable in a C function * doesn't work because callee saved registers may be outside the stack frame * defined by A6 (e.g. GCC generated code). * * [I don't think the ENTRY() macro will do the right thing with this -- glass] */ GLOBAL(getsp) movl %sp,%d0 | get current SP addql #4,%d0 | compensate for return address movl %d0,%a0 rts ENTRY(getvbr) movc %vbr,%d0 movl %d0,%a0 rts ENTRY(setvbr) movl %sp@(4),%d0 movc %d0,%vbr rts /* * Load a new CPU Root Pointer (CRP) into the MMU. * void loadcrp(struct mmu_rootptr *); */ ENTRY(loadcrp) movl %sp@(4),%a0 | arg1: &CRP movl #CACHE_CLR,%d0 movc %d0,%cacr | invalidate cache(s) pflusha | flush entire TLB pmove %a0@,%crp | load new user root pointer rts ENTRY(getcrp) movl %sp@(4),%a0 | arg1: &crp pmove %crp,%a0@ | *crpp = %crp rts /* * Get the physical address of the PTE for a given VA. */ ENTRY(ptest_addr) movl %sp@(4),%a1 | VA ptestr #5,%a1@,#7,%a0 | %a0 = addr of PTE movl %a0,%d0 | Result in %d0 (not a pointer return) rts /* * Set processor priority level calls. Most are implemented with * inline asm expansions. However, we need one instantiation here * in case some non-optimized code makes external references. * Most places will use the inlined functions param.h supplies. */ ENTRY(_getsr) clrl %d0 movw %sr,%d0 movl %a1,%d0 rts ENTRY(_spl) clrl %d0 movw %sr,%d0 movl %sp@(4),%d1 movw %d1,%sr rts ENTRY(_splraise) clrl %d0 movw %sr,%d0 movl %d0,%d1 andl #PSL_HIGHIPL,%d1 | old &= PSL_HIGHIPL cmpl %sp@(4),%d1 | (old - new) bge Lsplr movl %sp@(4),%d1 movw %d1,%sr Lsplr: rts /* * _delay(unsigned 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. * XXX: Currently this is set based on the CPU model, * XXX: but this should be determined at run time... */ GLOBAL(_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. */ #ifdef __ELF__ .align 8 #else .align 3 #endif L_delay: subl %d1,%d0 jgt L_delay rts | Define some addresses, mostly so DDB can print useful info. | Not using _C_LABEL() here because these symbols are never | referenced by any C code, and if the leading underscore | ever goes away, these lines turn into syntax errors... .set _KERNBASE3X,KERNBASE3X .set _MONSTART,SUN3X_MONSTART .set _PROM_BASE,SUN3X_PROM_BASE .set _MONEND,SUN3X_MONEND |The end!