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/system.h>
31 #include <asm/traps.h>
32 #include <asm/machdep.h>
33 #include <asm/setup.h>
34 #include <asm/pgtable.h>
37 asmlinkage void ret_from_fork(void);
41 * Return saved PC from a blocked thread
43 unsigned long thread_saved_pc(struct task_struct *tsk)
45 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
46 /* Check whether the thread is blocked in resume() */
47 if (in_sched_functions(sw->retpc))
48 return ((unsigned long *)sw->a6)[1];
54 * The idle loop on an m68k..
56 static void default_idle(void)
59 #if defined(MACH_ATARI_ONLY)
60 /* block out HSYNC on the atari (falcon) */
61 __asm__("stop #0x2200" : : : "cc");
63 __asm__("stop #0x2000" : : : "cc");
67 void (*idle)(void) = default_idle;
70 * The idle thread. There's no useful work to be
71 * done, so just try to conserve power and have a
72 * low exit latency (ie sit in a loop waiting for
73 * somebody to say that they'd like to reschedule)
77 /* endless idle loop with no priority at all */
79 while (!need_resched())
81 preempt_enable_no_resched();
87 void machine_restart(char * __unused)
94 void machine_halt(void)
101 void machine_power_off(void)
108 void (*pm_power_off)(void) = machine_power_off;
109 EXPORT_SYMBOL(pm_power_off);
111 void show_regs(struct pt_regs * regs)
114 printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
115 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
116 printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
117 regs->orig_d0, regs->d0, regs->a2, regs->a1);
118 printk("A0: %08lx D5: %08lx D4: %08lx\n",
119 regs->a0, regs->d5, regs->d4);
120 printk("D3: %08lx D2: %08lx D1: %08lx\n",
121 regs->d3, regs->d2, regs->d1);
122 if (!(regs->sr & PS_S))
123 printk("USP: %08lx\n", rdusp());
127 * Create a kernel thread
129 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
138 register long retval __asm__ ("d0");
139 register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
144 "trap #0\n\t" /* Linux/m68k system call */
145 "tstl %0\n\t" /* child or parent */
146 "jne 1f\n\t" /* parent - jump */
147 "lea %%sp@(%c7),%6\n\t" /* reload current */
149 "movel %3,%%sp@-\n\t" /* push argument */
150 "jsr %4@\n\t" /* call fn */
151 "movel %0,%%d1\n\t" /* pass exit value */
152 "movel %2,%%d0\n\t" /* exit */
156 : "i" (__NR_clone), "i" (__NR_exit),
157 "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
167 EXPORT_SYMBOL(kernel_thread);
169 void flush_thread(void)
171 unsigned long zero = 0;
173 current->thread.fs = __USER_DS;
175 asm volatile("frestore %0": :"m" (zero));
179 * "m68k_fork()".. By the time we get here, the
180 * non-volatile registers have also been saved on the
181 * stack. We do some ugly pointer stuff here.. (see
185 asmlinkage int m68k_fork(struct pt_regs *regs)
187 return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
190 asmlinkage int m68k_vfork(struct pt_regs *regs)
192 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
196 asmlinkage int m68k_clone(struct pt_regs *regs)
198 unsigned long clone_flags;
200 int __user *parent_tidptr, *child_tidptr;
202 /* syscall2 puts clone_flags in d1 and usp in d2 */
203 clone_flags = regs->d1;
205 parent_tidptr = (int __user *)regs->d3;
206 child_tidptr = (int __user *)regs->d4;
209 return do_fork(clone_flags, newsp, regs, 0,
210 parent_tidptr, child_tidptr);
213 int copy_thread(unsigned long clone_flags, unsigned long usp,
214 unsigned long unused,
215 struct task_struct * p, struct pt_regs * regs)
217 struct pt_regs * childregs;
218 struct switch_stack * childstack, *stack;
221 childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
226 retp = ((unsigned long *) regs);
227 stack = ((struct switch_stack *) retp) - 1;
229 childstack = ((struct switch_stack *) childregs) - 1;
230 *childstack = *stack;
231 childstack->retpc = (unsigned long)ret_from_fork;
234 p->thread.ksp = (unsigned long)childstack;
236 if (clone_flags & CLONE_SETTLS)
237 task_thread_info(p)->tp_value = regs->d5;
240 * Must save the current SFC/DFC value, NOT the value when
241 * the parent was last descheduled - RGH 10-08-96
243 p->thread.fs = get_fs().seg;
246 /* Copy the current fpu state */
247 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
249 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
250 if (CPU_IS_COLDFIRE) {
251 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
252 "fmovel %/fpiar,%1\n\t"
253 "fmovel %/fpcr,%2\n\t"
256 : "m" (p->thread.fp[0]),
257 "m" (p->thread.fpcntl[0]),
258 "m" (p->thread.fpcntl[1]),
259 "m" (p->thread.fpcntl[2])
262 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
263 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
265 : "m" (p->thread.fp[0]),
266 "m" (p->thread.fpcntl[0])
271 /* Restore the state in case the fpu was busy */
272 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
278 /* Fill in the fpu structure for a core dump. */
280 int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
287 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
288 memcpy(fpu->fpregs, current->thread.fp, 96);
289 /* Convert internal fpu reg representation
290 * into long double format
292 for (i = 0; i < 24; i += 3)
293 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
294 ((fpu->fpregs[i] & 0x0000ffff) << 16);
298 /* First dump the fpu context to avoid protocol violation. */
299 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
300 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
303 if (CPU_IS_COLDFIRE) {
304 asm volatile ("fmovel %/fpiar,%0\n\t"
305 "fmovel %/fpcr,%1\n\t"
306 "fmovel %/fpsr,%2\n\t"
307 "fmovemd %/fp0-%/fp7,%3"
309 : "m" (fpu->fpcntl[0]),
310 "m" (fpu->fpcntl[1]),
311 "m" (fpu->fpcntl[2]),
315 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
317 : "m" (fpu->fpcntl[0])
319 asm volatile ("fmovemx %/fp0-%/fp7,%0"
321 : "m" (fpu->fpregs[0])
327 EXPORT_SYMBOL(dump_fpu);
330 * sys_execve() executes a new program.
332 asmlinkage int sys_execve(const char __user *name,
333 const char __user *const __user *argv,
334 const char __user *const __user *envp)
338 struct pt_regs *regs = (struct pt_regs *) &name;
340 filename = getname(name);
341 error = PTR_ERR(filename);
342 if (IS_ERR(filename))
344 error = do_execve(filename, argv, envp, regs);
349 unsigned long get_wchan(struct task_struct *p)
351 unsigned long fp, pc;
352 unsigned long stack_page;
354 if (!p || p == current || p->state == TASK_RUNNING)
357 stack_page = (unsigned long)task_stack_page(p);
358 fp = ((struct switch_stack *)p->thread.ksp)->a6;
360 if (fp < stack_page+sizeof(struct thread_info) ||
361 fp >= 8184+stack_page)
363 pc = ((unsigned long *)fp)[1];
364 if (!in_sched_functions(pc))
366 fp = *(unsigned long *) fp;
367 } while (count++ < 16);