2 * linux/arch/m68k/kernel/process.c
4 * Copyright (C) 1995 Hamish Macdonald
6 * 68060 fixes by Jesper Skov
10 * This file handles the architecture-dependent parts of process handling..
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
18 #include <linux/slab.h>
20 #include <linux/smp.h>
21 #include <linux/stddef.h>
22 #include <linux/unistd.h>
23 #include <linux/ptrace.h>
24 #include <linux/user.h>
25 #include <linux/reboot.h>
26 #include <linux/init_task.h>
27 #include <linux/mqueue.h>
29 #include <asm/uaccess.h>
30 #include <asm/traps.h>
31 #include <asm/machdep.h>
32 #include <asm/setup.h>
33 #include <asm/pgtable.h>
36 asmlinkage void ret_from_fork(void);
40 * Return saved PC from a blocked thread
42 unsigned long thread_saved_pc(struct task_struct *tsk)
44 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
45 /* Check whether the thread is blocked in resume() */
46 if (in_sched_functions(sw->retpc))
47 return ((unsigned long *)sw->a6)[1];
53 * The idle loop on an m68k..
55 static void default_idle(void)
58 #if defined(MACH_ATARI_ONLY)
59 /* block out HSYNC on the atari (falcon) */
60 __asm__("stop #0x2200" : : : "cc");
62 __asm__("stop #0x2000" : : : "cc");
66 void (*idle)(void) = default_idle;
69 * The idle thread. There's no useful work to be
70 * done, so just try to conserve power and have a
71 * low exit latency (ie sit in a loop waiting for
72 * somebody to say that they'd like to reschedule)
76 /* endless idle loop with no priority at all */
78 while (!need_resched())
80 schedule_preempt_disabled();
84 void machine_restart(char * __unused)
91 void machine_halt(void)
98 void machine_power_off(void)
105 void (*pm_power_off)(void) = machine_power_off;
106 EXPORT_SYMBOL(pm_power_off);
108 void show_regs(struct pt_regs * regs)
111 printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
112 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
113 printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
114 regs->orig_d0, regs->d0, regs->a2, regs->a1);
115 printk("A0: %08lx D5: %08lx D4: %08lx\n",
116 regs->a0, regs->d5, regs->d4);
117 printk("D3: %08lx D2: %08lx D1: %08lx\n",
118 regs->d3, regs->d2, regs->d1);
119 if (!(regs->sr & PS_S))
120 printk("USP: %08lx\n", rdusp());
124 * Create a kernel thread
126 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
135 register long retval __asm__ ("d0");
136 register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
141 "trap #0\n\t" /* Linux/m68k system call */
142 "tstl %0\n\t" /* child or parent */
143 "jne 1f\n\t" /* parent - jump */
145 "lea %%sp@(%c7),%6\n\t" /* reload current */
148 "movel %3,%%sp@-\n\t" /* push argument */
149 "jsr %4@\n\t" /* call fn */
150 "movel %0,%%d1\n\t" /* pass exit value */
151 "movel %2,%%d0\n\t" /* exit */
155 : "i" (__NR_clone), "i" (__NR_exit),
156 "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
166 EXPORT_SYMBOL(kernel_thread);
168 void flush_thread(void)
170 current->thread.fs = __USER_DS;
173 unsigned long zero = 0;
174 asm volatile("frestore %0": :"m" (zero));
180 * "m68k_fork()".. By the time we get here, the
181 * non-volatile registers have also been saved on the
182 * stack. We do some ugly pointer stuff here.. (see
186 asmlinkage int m68k_fork(struct pt_regs *regs)
189 return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
195 asmlinkage int m68k_vfork(struct pt_regs *regs)
197 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
201 asmlinkage int m68k_clone(struct pt_regs *regs)
203 unsigned long clone_flags;
205 int __user *parent_tidptr, *child_tidptr;
207 /* syscall2 puts clone_flags in d1 and usp in d2 */
208 clone_flags = regs->d1;
210 parent_tidptr = (int __user *)regs->d3;
211 child_tidptr = (int __user *)regs->d4;
214 return do_fork(clone_flags, newsp, regs, 0,
215 parent_tidptr, child_tidptr);
218 int copy_thread(unsigned long clone_flags, unsigned long usp,
219 unsigned long unused,
220 struct task_struct * p, struct pt_regs * regs)
222 struct pt_regs * childregs;
223 struct switch_stack * childstack, *stack;
226 childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
231 retp = ((unsigned long *) regs);
232 stack = ((struct switch_stack *) retp) - 1;
234 childstack = ((struct switch_stack *) childregs) - 1;
235 *childstack = *stack;
236 childstack->retpc = (unsigned long)ret_from_fork;
239 p->thread.ksp = (unsigned long)childstack;
241 if (clone_flags & CLONE_SETTLS)
242 task_thread_info(p)->tp_value = regs->d5;
245 * Must save the current SFC/DFC value, NOT the value when
246 * the parent was last descheduled - RGH 10-08-96
248 p->thread.fs = get_fs().seg;
252 /* Copy the current fpu state */
253 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
255 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
256 if (CPU_IS_COLDFIRE) {
257 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
258 "fmovel %/fpiar,%1\n\t"
259 "fmovel %/fpcr,%2\n\t"
262 : "m" (p->thread.fp[0]),
263 "m" (p->thread.fpcntl[0]),
264 "m" (p->thread.fpcntl[1]),
265 "m" (p->thread.fpcntl[2])
268 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
269 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
271 : "m" (p->thread.fp[0]),
272 "m" (p->thread.fpcntl[0])
277 /* Restore the state in case the fpu was busy */
278 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
280 #endif /* CONFIG_FPU */
285 /* Fill in the fpu structure for a core dump. */
287 int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
294 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
295 memcpy(fpu->fpregs, current->thread.fp, 96);
296 /* Convert internal fpu reg representation
297 * into long double format
299 for (i = 0; i < 24; i += 3)
300 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
301 ((fpu->fpregs[i] & 0x0000ffff) << 16);
305 /* First dump the fpu context to avoid protocol violation. */
306 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
307 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
310 if (CPU_IS_COLDFIRE) {
311 asm volatile ("fmovel %/fpiar,%0\n\t"
312 "fmovel %/fpcr,%1\n\t"
313 "fmovel %/fpsr,%2\n\t"
314 "fmovemd %/fp0-%/fp7,%3"
316 : "m" (fpu->fpcntl[0]),
317 "m" (fpu->fpcntl[1]),
318 "m" (fpu->fpcntl[2]),
322 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
324 : "m" (fpu->fpcntl[0])
326 asm volatile ("fmovemx %/fp0-%/fp7,%0"
328 : "m" (fpu->fpregs[0])
334 EXPORT_SYMBOL(dump_fpu);
335 #endif /* CONFIG_FPU */
338 * sys_execve() executes a new program.
340 asmlinkage int sys_execve(const char __user *name,
341 const char __user *const __user *argv,
342 const char __user *const __user *envp)
346 struct pt_regs *regs = (struct pt_regs *) &name;
348 filename = getname(name);
349 error = PTR_ERR(filename);
350 if (IS_ERR(filename))
352 error = do_execve(filename, argv, envp, regs);
357 unsigned long get_wchan(struct task_struct *p)
359 unsigned long fp, pc;
360 unsigned long stack_page;
362 if (!p || p == current || p->state == TASK_RUNNING)
365 stack_page = (unsigned long)task_stack_page(p);
366 fp = ((struct switch_stack *)p->thread.ksp)->a6;
368 if (fp < stack_page+sizeof(struct thread_info) ||
369 fp >= 8184+stack_page)
371 pc = ((unsigned long *)fp)[1];
372 if (!in_sched_functions(pc))
374 fp = *(unsigned long *) fp;
375 } while (count++ < 16);