/* $NetBSD: locore.s,v 1.41 2000/05/31 05:06:57 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. 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 */ #include "opt_compat_netbsd.h" #include "opt_compat_svr4.h" #include "opt_compat_sunos.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 #KERNBASE, 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. movl _C_LABEL(proc0paddr),a1 | get proc0 pcb addr lea a1@(USPACE-4),sp | set SSP to last word movl #USRSTACK-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. /* * Final preparation for calling main. * * Create a fake exception frame that returns to user mode, * and save its address in p->p_md.md_regs for cpu_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@- | 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 sp,a1 | a1=trapframe lea _C_LABEL(proc0),a0 | proc0.p_md.md_regs = movl a1,a0@(P_MDREGS) | trapframe movl a2,a1@(FR_SP) | a2 == usp (from above) pea a1@ | push &trapframe jbsr _C_LABEL(main) | main(&trapframe) addql #4,sp | help DDB backtrace trap #15 | should not get here | This is used by cpu_fork() to return to user mode. | It is called with SP pointing to a struct trapframe. GLOBAL(proc_do_uret) movl sp@(FR_SP),a0 | grab and load movl a0,usp | user SP moveml sp@+,#0x7FFF | load most registers (all but SSP) addql #8,sp | pop SSP and stack adjust count rte /* * proc_trampoline: * This is used by cpu_set_kpc() to "push" a function call onto the * kernel stack of some process, very much like a signal delivery. * When we get here, the stack has: * * SP+8: switchframe from before cpu_set_kpc * SP+4: void *arg; * SP: u_long func; * * On entry, the switchframe pushed by cpu_set_kpc has already been * popped off the stack, so all this needs to do is pop the function * pointer into a register, call it, then pop the arg, and finally * return using the switchframe that remains on the stack. */ GLOBAL(proc_trampoline) movl sp@+,a0 | function pointer jbsr a0@ | (*func)(arg) addql #4,sp | toss the arg rts | as cpu_switch would do | 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(curproc),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 /* Use common m68k sigreturn */ #include /* * 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 */ #define INTERRUPT_SAVEREG \ moveml #0xC0C0,sp@- #define INTERRUPT_RESTORE \ moveml sp@+,#0x0303 /* * 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. */ .align 2 GLOBAL(_isr_autovec) INTERRUPT_SAVEREG jbsr _C_LABEL(isr_autovec) INTERRUPT_RESTORE jra _ASM_LABEL(rei) /* clock: see clock.c */ .align 2 GLOBAL(_isr_clock) INTERRUPT_SAVEREG jbsr _C_LABEL(clock_intr) INTERRUPT_RESTORE jra _ASM_LABEL(rei) | Handler for all vectored interrupts (i.e. VME interrupts) .align 2 GLOBAL(_isr_vectored) INTERRUPT_SAVEREG jbsr _C_LABEL(isr_vectored) INTERRUPT_RESTORE jra _ASM_LABEL(rei) #undef INTERRUPT_SAVEREG #undef INTERRUPT_RESTORE /* 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 0,0,0,0,0,0,0,0,0,0 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 paniced? 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 jbsr _C_LABEL(trap) | go handle it lea sp@(12),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 .text /* * Primitives */ /* * Use common m68k support routines. */ #include BSS(want_resched,4) /* * Use common m68k process manipulation routines. */ #include | Message for Lbadsw panic Lsw0: .asciz "cpu_switch" .even .data GLOBAL(masterpaddr) | XXX compatibility (debuggers) GLOBAL(curpcb) .long 0 ASBSS(nullpcb,SIZEOF_PCB) .text /* * At exit of a process, do a cpu_switch for the last time. * Switch to a safe stack and PCB, and select a new process to run. The * old stack and u-area will be freed by the reaper. */ ENTRY(switch_exit) movl sp@(4),a0 | struct proc *p | save state into garbage pcb movl #_ASM_LABEL(nullpcb),_C_LABEL(curpcb) lea _ASM_LABEL(tmpstk),sp | goto a tmp stack /* Schedule the vmspace and stack to be freed. */ movl a0,sp@- | exit2(p) jbsr _C_LABEL(exit2) /* Don't pop the proc; pass it to cpu_switch(). */ jra _C_LABEL(cpu_switch) /* * When no processes are on the runq, cpu_switch() branches to idle * to wait for something to come ready. */ .data GLOBAL(Idle_count) .long 0 .text Lidle: stop #PSL_LOWIPL GLOBAL(_Idle) | See clock.c movw #PSL_HIGHIPL,sr addql #1, _C_LABEL(Idle_count) tstl _C_LABEL(sched_whichqs) jeq Lidle movw #PSL_LOWIPL,sr jra Lsw1 Lbadsw: movl #Lsw0,sp@- jbsr _C_LABEL(panic) /*NOTREACHED*/ /* * cpu_switch() * Hacked for sun3 * XXX - Arg 1 is a proc pointer (curproc) but this doesn't use it. * XXX - Sould we use p->p_addr instead of curpcb? -gwr */ ENTRY(cpu_switch) movl _C_LABEL(curpcb),a1 | current pcb movw sr,a1@(PCB_PS) | save sr before changing ipl #ifdef notyet movl _C_LABEL(curproc),sp@- | remember last proc running #endif clrl _C_LABEL(curproc) Lsw1: /* * Find the highest-priority queue that isn't empty, * then take the first proc from that queue. */ clrl d0 lea _C_LABEL(sched_whichqs),a0 movl a0@,d1 Lswchk: btst d0,d1 jne Lswfnd addqb #1,d0 cmpb #32,d0 jne Lswchk jra _C_LABEL(_Idle) Lswfnd: movw #PSL_HIGHIPL,sr | lock out interrupts movl a0@,d1 | and check again... bclr d0,d1 jeq Lsw1 | proc moved, rescan movl d1,a0@ | update whichqs moveq #1,d1 | double check for higher priority lsll d0,d1 | process (which may have snuck in subql #1,d1 | while we were finding this one) andl a0@,d1 jeq Lswok | no one got in, continue movl a0@,d1 bset d0,d1 | otherwise put this one back movl d1,a0@ jra Lsw1 | and rescan Lswok: movl d0,d1 lslb #3,d1 | convert queue number to index addl #_C_LABEL(sched_qs),d1 | locate queue (q) movl d1,a1 cmpl a1@(P_FORW),a1 | anyone on queue? jeq Lbadsw | no, panic movl a1@(P_FORW),a0 | p = q->p_forw #ifdef DIAGNOSTIC tstl a0@(P_WCHAN) jne Lbadsw cmpb #SRUN,a0@(P_STAT) jne Lbadsw #endif movl a0@(P_FORW),a1@(P_FORW) | q->p_forw = p->p_forw movl a0@(P_FORW),a1 | q = p->p_forw movl a0@(P_BACK),a1@(P_BACK) | q->p_back = p->p_back cmpl a0@(P_FORW),d1 | anyone left on queue? jeq Lsw2 | no, skip movl _C_LABEL(sched_whichqs),d1 bset d0,d1 | yes, reset bit movl d1,_C_LABEL(sched_whichqs) Lsw2: /* p->p_cpu initialized in fork1() for single-processor */ movb #SONPROC,a0@(P_STAT) | p->p_stat = SONPROC movl a0,_C_LABEL(curproc) clrl _C_LABEL(want_resched) #ifdef notyet movl sp@+,a1 | XXX - Make this work! cmpl a0,a1 | switching to same proc? jeq Lswdone | yes, skip save and restore #endif /* * Save state of previous process in its pcb. */ movl _C_LABEL(curpcb),a1 moveml #0xFCFC,a1@(PCB_REGS) | save non-scratch registers movl usp,a2 | grab USP (a2 has been saved) movl a2,a1@(PCB_USP) | and save it tstl _C_LABEL(fputype) | Do we have an fpu? jeq Lswnofpsave | No? Then don't try save. lea a1@(PCB_FPCTX),a2 | pointer to FP save area fsave a2@ | save FP state tstb a2@ | null state frame? jeq Lswnofpsave | yes, all done fmovem fp0-fp7,a2@(FPF_REGS) | save FP general regs fmovem fpcr/fpsr/fpi,a2@(FPF_FPCR) | save FP control regs Lswnofpsave: /* * Now that we have saved all the registers that must be * preserved, we are free to use those registers until * we load the registers for the switched-to process. * In this section, keep: a0=curproc, a1=curpcb */ clrl a0@(P_BACK) | clear back link movl a0@(P_ADDR),a1 | get p_addr movl a1,_C_LABEL(curpcb) /* * Load the new VM context (new MMU root pointer) */ movl a0@(P_VMSPACE),a2 | vm = p->p_vmspace #ifdef DIAGNOSTIC tstl a2 | vm == VM_MAP_NULL? jeq Lbadsw | panic #endif #ifdef PMAP_DEBUG /* When debugging just call _pmap_switch(). */ movl a2@(VM_PMAP),a2 | pmap = vm->vm_map.pmap pea a2@ | push pmap jbsr _C_LABEL(_pmap_switch) | _pmap_switch(pmap) addql #4,sp movl _C_LABEL(curpcb),a1 | restore p_addr #else /* Otherwise, use this inline version. */ lea _C_LABEL(kernel_crp), a3 | our CPU Root Ptr. (CRP) movl a2@(VM_PMAP),a2 | pmap = vm->vm_map.pmap movl a2@(PM_A_PHYS),d0 | phys = pmap->pm_a_phys cmpl a3@(4),d0 | == kernel_crp.rp_addr ? jeq Lsame_mmuctx | skip loadcrp/flush /* OK, it is a new MMU context. Load it up. */ movl d0,a3@(4) movl #CACHE_CLR,d0 movc d0,cacr | invalidate cache(s) pflusha | flush entire TLB pmove a3@,crp | load new user root pointer Lsame_mmuctx: #endif /* * Reload the registers for the new process. * After this point we can only use d0,d1,a0,a1 */ moveml a1@(PCB_REGS),#0xFCFC | reload registers movl a1@(PCB_USP),a0 movl a0,usp | and USP tstl _C_LABEL(fputype) | If we don't have an fpu, jeq Lres_skip | don't try to restore it. lea a1@(PCB_FPCTX),a0 | pointer to FP save area tstb a0@ | null state frame? jeq Lresfprest | yes, easy fmovem a0@(FPF_FPCR),fpcr/fpsr/fpi | restore FP control regs fmovem a0@(FPF_REGS),fp0-fp7 | restore FP general regs Lresfprest: frestore a0@ | restore state Lres_skip: movw a1@(PCB_PS),d0 | no, restore PS #ifdef DIAGNOSTIC btst #13,d0 | supervisor mode? jeq Lbadsw | no? panic! #endif movw d0,sr | OK, restore PS moveq #1,d0 | return 1 (for alternate returns) rts /* * savectx(pcb) * Update pcb, saving current processor state. */ ENTRY(savectx) movl sp@(4),a1 movw sr,a1@(PCB_PS) movl usp,a0 | grab USP movl a0,a1@(PCB_USP) | and save it moveml #0xFCFC,a1@(PCB_REGS) | save non-scratch registers tstl _C_LABEL(fputype) | Do we have FPU? jeq Lsavedone | No? Then don't save state. lea a1@(PCB_FPCTX),a0 | pointer to FP save area fsave a0@ | save FP state tstb a0@ | null state frame? jeq Lsavedone | yes, all done fmovem fp0-fp7,a0@(FPF_REGS) | save FP general regs fmovem fpcr/fpsr/fpi,a0@(FPF_FPCR) | save FP control regs Lsavedone: moveq #0,d0 | return 0 rts /* suline() */ #ifdef DEBUG .data ASGLOBAL(fulltflush) .long 0 ASGLOBAL(fullcflush) .long 0 .text #endif /* * Invalidate entire TLB. */ ENTRY(TBIA) _C_LABEL(_TBIA): pflusha movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip d-cache rts /* * Invalidate any TLB entry for given VA (TB Invalidate Single) */ ENTRY(TBIS) #ifdef DEBUG tstl _ASM_LABEL(fulltflush) | being conservative? jne _C_LABEL(_TBIA) | yes, flush entire TLB #endif movl sp@(4),a0 pflush #0,#0,a0@ | flush address from both sides movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip data cache rts /* * Invalidate supervisor side of TLB */ ENTRY(TBIAS) #ifdef DEBUG tstl _ASM_LABEL(fulltflush) | being conservative? jne _C_LABEL(_TBIA) | yes, flush everything #endif pflush #4,#4 | flush supervisor TLB entries movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip d-cache rts /* * Invalidate user side of TLB */ ENTRY(TBIAU) #ifdef DEBUG tstl _ASM_LABEL(fulltflush) | being conservative? jne _C_LABEL(_TBIA) | yes, flush everything #endif pflush #0,#4 | flush user TLB entries movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip d-cache rts /* * Invalidate instruction cache */ ENTRY(ICIA) movl #IC_CLEAR,d0 movc d0,cacr | invalidate i-cache rts /* * Invalidate data cache. * NOTE: we do not flush 68030 on-chip cache as there are no aliasing * problems with DC_WA. The only cases we have to worry about are context * switch and TLB changes, both of which are handled "in-line" in resume * and TBI*. */ ENTRY(DCIA) __DCIA: rts ENTRY(DCIS) __DCIS: rts /* * Invalidate data cache. */ ENTRY(DCIU) movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip d-cache rts /* ICPL, ICPP, DCPL, DCPP, DCPA, DCFL, DCFP */ ENTRY(PCIA) movl #DC_CLEAR,d0 movc d0,cacr | invalidate on-chip d-cache rts 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 rts ENTRY(getsfc) movc sfc,d0 rts ENTRY(getdfc) movc dfc,d0 rts ENTRY(getvbr) movc vbr, d0 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 /* * Get the physical address of the PTE for a given VA. */ ENTRY(ptest_addr) movl sp@(4),a0 | VA ptestr #5,a0@,#7,a1 | a1 = addr of PTE movl a1,d0 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 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 /* * Save and restore 68881 state. */ ENTRY(m68881_save) movl sp@(4),a0 | save area pointer fsave a0@ | save state tstb a0@ | null state frame? jeq Lm68881sdone | yes, all done fmovem fp0-fp7,a0@(FPF_REGS) | save FP general regs fmovem fpcr/fpsr/fpi,a0@(FPF_FPCR) | save FP control regs Lm68881sdone: rts ENTRY(m68881_restore) movl sp@(4),a0 | save area pointer tstb a0@ | null state frame? jeq Lm68881rdone | yes, easy fmovem a0@(FPF_FPCR),fpcr/fpsr/fpi | restore FP control regs fmovem a0@(FPF_REGS),fp0-fp7 | restore FP general regs Lm68881rdone: frestore a0@ | restore state 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. */ .align 8 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 _KERNBASE,KERNBASE .set _MONSTART,SUN3X_MONSTART .set _PROM_BASE,SUN3X_PROM_BASE .set _MONEND,SUN3X_MONEND |The end!