2 * linux/arch/m68knommu/kernel/process.c
4 * Copyright (C) 1995 Hamish Macdonald
6 * 68060 fixes by Jesper Skov
9 * Copyright (C) 2000-2002, David McCullough <davidm@snapgear.com>
13 * This file handles the architecture-dependent parts of process handling..
16 #include <linux/config.h>
17 #include <linux/module.h>
18 #include <linux/errno.h>
19 #include <linux/sched.h>
20 #include <linux/kernel.h>
22 #include <linux/smp.h>
23 #include <linux/smp_lock.h>
24 #include <linux/stddef.h>
25 #include <linux/unistd.h>
26 #include <linux/ptrace.h>
27 #include <linux/slab.h>
28 #include <linux/user.h>
29 #include <linux/a.out.h>
30 #include <linux/interrupt.h>
31 #include <linux/reboot.h>
33 #include <asm/uaccess.h>
34 #include <asm/system.h>
35 #include <asm/traps.h>
36 #include <asm/machdep.h>
37 #include <asm/setup.h>
38 #include <asm/pgtable.h>
40 asmlinkage void ret_from_fork(void);
44 * The idle loop on an m68knommu..
46 void default_idle(void)
49 while (!need_resched()) {
50 /* This stop will re-enable interrupts */
51 __asm__("stop #0x2000" : : : "cc");
57 void (*idle)(void) = default_idle;
60 * The idle thread. There's no useful work to be
61 * done, so just try to conserve power and have a
62 * low exit latency (ie sit in a loop waiting for
63 * somebody to say that they'd like to reschedule)
67 /* endless idle loop with no priority at all */
70 preempt_enable_no_resched();
76 void machine_restart(char * __unused)
83 EXPORT_SYMBOL(machine_restart);
85 void machine_halt(void)
92 EXPORT_SYMBOL(machine_halt);
94 void machine_power_off(void)
101 EXPORT_SYMBOL(machine_power_off);
103 void show_regs(struct pt_regs * regs)
105 printk(KERN_NOTICE "\n");
106 printk(KERN_NOTICE "Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
107 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
108 printk(KERN_NOTICE "ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
109 regs->orig_d0, regs->d0, regs->a2, regs->a1);
110 printk(KERN_NOTICE "A0: %08lx D5: %08lx D4: %08lx\n",
111 regs->a0, regs->d5, regs->d4);
112 printk(KERN_NOTICE "D3: %08lx D2: %08lx D1: %08lx\n",
113 regs->d3, regs->d2, regs->d1);
114 if (!(regs->sr & PS_S))
115 printk(KERN_NOTICE "USP: %08lx\n", rdusp());
119 * Create a kernel thread
121 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
124 long clone_arg = flags | CLONE_VM;
130 __asm__ __volatile__ (
131 "movel %%sp, %%d2\n\t"
135 "cmpl %%sp, %%d2\n\t"
137 "movel %3, %%sp@-\n\t"
149 : "cc", "%d0", "%d1", "%d2");
155 void flush_thread(void)
158 unsigned long zero = 0;
161 current->thread.fs = __USER_DS;
164 asm volatile (".chip 68k/68881\n\t"
166 ".chip 68k" : : "a" (&zero));
171 * "m68k_fork()".. By the time we get here, the
172 * non-volatile registers have also been saved on the
173 * stack. We do some ugly pointer stuff here.. (see
177 asmlinkage int m68k_fork(struct pt_regs *regs)
179 /* fork almost works, enough to trick you into looking elsewhere :-( */
183 asmlinkage int m68k_vfork(struct pt_regs *regs)
185 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
188 asmlinkage int m68k_clone(struct pt_regs *regs)
190 unsigned long clone_flags;
193 /* syscall2 puts clone_flags in d1 and usp in d2 */
194 clone_flags = regs->d1;
198 return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
201 int copy_thread(int nr, unsigned long clone_flags,
202 unsigned long usp, unsigned long topstk,
203 struct task_struct * p, struct pt_regs * regs)
205 struct pt_regs * childregs;
206 struct switch_stack * childstack, *stack;
207 unsigned long stack_offset, *retp;
209 stack_offset = THREAD_SIZE - sizeof(struct pt_regs);
210 childregs = (struct pt_regs *) ((unsigned long) p->thread_info + stack_offset);
215 retp = ((unsigned long *) regs);
216 stack = ((struct switch_stack *) retp) - 1;
218 childstack = ((struct switch_stack *) childregs) - 1;
219 *childstack = *stack;
220 childstack->retpc = (unsigned long)ret_from_fork;
223 p->thread.ksp = (unsigned long)childstack;
225 * Must save the current SFC/DFC value, NOT the value when
226 * the parent was last descheduled - RGH 10-08-96
228 p->thread.fs = get_fs().seg;
232 /* Copy the current fpu state */
233 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
235 if (p->thread.fpstate[0])
236 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
237 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
238 : : "m" (p->thread.fp[0]), "m" (p->thread.fpcntl[0])
240 /* Restore the state in case the fpu was busy */
241 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
248 /* Fill in the fpu structure for a core dump. */
250 int dump_fpu(struct pt_regs *regs, struct user_m68kfp_struct *fpu)
258 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
259 memcpy(fpu->fpregs, current->thread.fp, 96);
260 /* Convert internal fpu reg representation
261 * into long double format
263 for (i = 0; i < 24; i += 3)
264 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
265 ((fpu->fpregs[i] & 0x0000ffff) << 16);
269 /* First dump the fpu context to avoid protocol violation. */
270 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
274 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
275 :: "m" (fpu->fpcntl[0])
277 asm volatile ("fmovemx %/fp0-%/fp7,%0"
278 :: "m" (fpu->fpregs[0])
285 * fill in the user structure for a core dump..
287 void dump_thread(struct pt_regs * regs, struct user * dump)
289 struct switch_stack *sw;
291 /* changed the size calculations - should hopefully work better. lbt */
292 dump->magic = CMAGIC;
293 dump->start_code = 0;
294 dump->start_stack = rdusp() & ~(PAGE_SIZE - 1);
295 dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
296 dump->u_dsize = ((unsigned long) (current->mm->brk +
297 (PAGE_SIZE-1))) >> PAGE_SHIFT;
298 dump->u_dsize -= dump->u_tsize;
301 if (dump->start_stack < TASK_SIZE)
302 dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
304 dump->u_ar0 = (struct user_regs_struct *)((int)&dump->regs - (int)dump);
305 sw = ((struct switch_stack *)regs) - 1;
306 dump->regs.d1 = regs->d1;
307 dump->regs.d2 = regs->d2;
308 dump->regs.d3 = regs->d3;
309 dump->regs.d4 = regs->d4;
310 dump->regs.d5 = regs->d5;
311 dump->regs.d6 = sw->d6;
312 dump->regs.d7 = sw->d7;
313 dump->regs.a0 = regs->a0;
314 dump->regs.a1 = regs->a1;
315 dump->regs.a2 = regs->a2;
316 dump->regs.a3 = sw->a3;
317 dump->regs.a4 = sw->a4;
318 dump->regs.a5 = sw->a5;
319 dump->regs.a6 = sw->a6;
320 dump->regs.d0 = regs->d0;
321 dump->regs.orig_d0 = regs->orig_d0;
322 dump->regs.stkadj = regs->stkadj;
323 dump->regs.sr = regs->sr;
324 dump->regs.pc = regs->pc;
325 dump->regs.fmtvec = (regs->format << 12) | regs->vector;
326 /* dump floating point stuff */
327 dump->u_fpvalid = dump_fpu (regs, &dump->m68kfp);
331 * Generic dumping code. Used for panic and debug.
333 void dump(struct pt_regs *fp)
339 printk(KERN_EMERG "\nCURRENT PROCESS:\n\n");
340 printk(KERN_EMERG "COMM=%s PID=%d\n", current->comm, current->pid);
343 printk(KERN_EMERG "TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
344 (int) current->mm->start_code,
345 (int) current->mm->end_code,
346 (int) current->mm->start_data,
347 (int) current->mm->end_data,
348 (int) current->mm->end_data,
349 (int) current->mm->brk);
350 printk(KERN_EMERG "USER-STACK=%08x KERNEL-STACK=%08x\n\n",
351 (int) current->mm->start_stack,
352 (int)(((unsigned long) current) + THREAD_SIZE));
355 printk(KERN_EMERG "PC: %08lx\n", fp->pc);
356 printk(KERN_EMERG "SR: %08lx SP: %08lx\n", (long) fp->sr, (long) fp);
357 printk(KERN_EMERG "d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
358 fp->d0, fp->d1, fp->d2, fp->d3);
359 printk(KERN_EMERG "d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n",
360 fp->d4, fp->d5, fp->a0, fp->a1);
361 printk(KERN_EMERG "\nUSP: %08x TRAPFRAME: %08x\n", (unsigned int) rdusp(),
364 printk(KERN_EMERG "\nCODE:");
365 tp = ((unsigned char *) fp->pc) - 0x20;
366 for (sp = (unsigned long *) tp, i = 0; (i < 0x40); i += 4) {
368 printk(KERN_EMERG "\n%08x: ", (int) (tp + i));
369 printk(KERN_EMERG "%08x ", (int) *sp++);
371 printk(KERN_EMERG "\n");
373 printk(KERN_EMERG "\nKERNEL STACK:");
374 tp = ((unsigned char *) fp) - 0x40;
375 for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
377 printk(KERN_EMERG "\n%08x: ", (int) (tp + i));
378 printk(KERN_EMERG "%08x ", (int) *sp++);
380 printk(KERN_EMERG "\n");
381 printk(KERN_EMERG "\n");
383 printk(KERN_EMERG "\nUSER STACK:");
384 tp = (unsigned char *) (rdusp() - 0x10);
385 for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
387 printk(KERN_EMERG "\n%08x: ", (int) (tp + i));
388 printk(KERN_EMERG "%08x ", (int) *sp++);
390 printk(KERN_EMERG "\n\n");
394 * sys_execve() executes a new program.
396 asmlinkage int sys_execve(char *name, char **argv, char **envp)
400 struct pt_regs *regs = (struct pt_regs *) &name;
403 filename = getname(name);
404 error = PTR_ERR(filename);
405 if (IS_ERR(filename))
407 error = do_execve(filename, argv, envp, regs);
414 unsigned long get_wchan(struct task_struct *p)
416 unsigned long fp, pc;
417 unsigned long stack_page;
419 if (!p || p == current || p->state == TASK_RUNNING)
422 stack_page = (unsigned long)p;
423 fp = ((struct switch_stack *)p->thread.ksp)->a6;
425 if (fp < stack_page+sizeof(struct thread_info) ||
426 fp >= 8184+stack_page)
428 pc = ((unsigned long *)fp)[1];
429 if (!in_sched_functions(pc))
431 fp = *(unsigned long *) fp;
432 } while (count++ < 16);
437 * Return saved PC of a blocked thread.
439 unsigned long thread_saved_pc(struct task_struct *tsk)
441 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
443 /* Check whether the thread is blocked in resume() */
444 if (in_sched_functions(sw->retpc))
445 return ((unsigned long *)sw->a6)[1];