2 * linux/arch/m32r/kernel/process.c
4 * Copyright (c) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata,
6 * Taken from sh version.
7 * Copyright (C) 1995 Linus Torvalds
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
13 #define DPRINTK(fmt, args...) printk("%s:%d:%s: " fmt, __FILE__, __LINE__, \
16 #define DPRINTK(fmt, args...)
20 * This file handles the architecture-dependent parts of process handling..
24 #include <linux/config.h>
25 #include <linux/module.h>
26 #include <linux/ptrace.h>
27 #include <linux/unistd.h>
28 #include <linux/slab.h>
29 #include <linux/hardirq.h>
32 #include <asm/uaccess.h>
33 #include <asm/mmu_context.h>
37 #include <linux/err.h>
39 static int hlt_counter=0;
42 * Return saved PC of a blocked thread.
44 unsigned long thread_saved_pc(struct task_struct *tsk)
46 return tsk->thread.lr;
50 * Powermanagement idle function, if any..
52 void (*pm_idle)(void) = NULL;
53 EXPORT_SYMBOL(pm_idle);
55 void (*pm_power_off)(void) = NULL;
56 EXPORT_SYMBOL(pm_power_off);
58 void disable_hlt(void)
63 EXPORT_SYMBOL(disable_hlt);
70 EXPORT_SYMBOL(enable_hlt);
73 * We use this is we don't have any better
76 void default_idle(void)
78 /* M32R_FIXME: Please use "cpu_sleep" mode. */
83 * On SMP it's slightly faster (but much more power-consuming!)
84 * to poll the ->work.need_resched flag instead of waiting for the
85 * cross-CPU IPI to arrive. Use this option with caution.
87 static void poll_idle (void)
94 * The idle thread. There's no useful work to be
95 * done, so just try to conserve power and have a
96 * low exit latency (ie sit in a loop waiting for
97 * somebody to say that they'd like to reschedule)
101 /* endless idle loop with no priority at all */
103 while (!need_resched()) {
104 void (*idle)(void) = pm_idle;
111 preempt_enable_no_resched();
117 void machine_restart(char *__unused)
119 printk("Please push reset button!\n");
124 void machine_halt(void)
126 printk("Please push reset button!\n");
131 void machine_power_off(void)
136 static int __init idle_setup (char *str)
138 if (!strncmp(str, "poll", 4)) {
139 printk("using poll in idle threads.\n");
141 } else if (!strncmp(str, "sleep", 4)) {
142 printk("using sleep in idle threads.\n");
143 pm_idle = default_idle;
149 __setup("idle=", idle_setup);
151 void show_regs(struct pt_regs * regs)
154 printk("BPC[%08lx]:PSW[%08lx]:LR [%08lx]:FP [%08lx]\n", \
155 regs->bpc, regs->psw, regs->lr, regs->fp);
156 printk("BBPC[%08lx]:BBPSW[%08lx]:SPU[%08lx]:SPI[%08lx]\n", \
157 regs->bbpc, regs->bbpsw, regs->spu, regs->spi);
158 printk("R0 [%08lx]:R1 [%08lx]:R2 [%08lx]:R3 [%08lx]\n", \
159 regs->r0, regs->r1, regs->r2, regs->r3);
160 printk("R4 [%08lx]:R5 [%08lx]:R6 [%08lx]:R7 [%08lx]\n", \
161 regs->r4, regs->r5, regs->r6, regs->r7);
162 printk("R8 [%08lx]:R9 [%08lx]:R10[%08lx]:R11[%08lx]\n", \
163 regs->r8, regs->r9, regs->r10, regs->r11);
164 printk("R12[%08lx]\n", \
167 #if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
168 printk("ACC0H[%08lx]:ACC0L[%08lx]\n", \
169 regs->acc0h, regs->acc0l);
170 printk("ACC1H[%08lx]:ACC1L[%08lx]\n", \
171 regs->acc1h, regs->acc1l);
172 #elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
173 printk("ACCH[%08lx]:ACCL[%08lx]\n", \
174 regs->acch, regs->accl);
176 #error unknown isa configuration
181 * Create a kernel thread
185 * This is the mechanism for creating a new kernel thread.
187 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
188 * who haven't done an "execve()") should use this: it will work within
189 * a system call from a "real" process, but the process memory space will
190 * not be free'd until both the parent and the child have exited.
192 static void kernel_thread_helper(void *nouse, int (*fn)(void *), void *arg)
198 int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
202 memset(®s, 0, sizeof (regs));
203 regs.r1 = (unsigned long)fn;
204 regs.r2 = (unsigned long)arg;
206 regs.bpc = (unsigned long)kernel_thread_helper;
208 regs.psw = M32R_PSW_BIE;
210 /* Ok, create the new process. */
211 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL,
216 * Free current thread data structures etc..
218 void exit_thread(void)
221 DPRINTK("pid = %d\n", current->pid);
224 void flush_thread(void)
226 DPRINTK("pid = %d\n", current->pid);
227 memset(¤t->thread.debug_trap, 0, sizeof(struct debug_trap));
230 void release_thread(struct task_struct *dead_task)
233 DPRINTK("pid = %d\n", dead_task->pid);
236 /* Fill in the fpu structure for a core dump.. */
237 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
239 return 0; /* Task didn't use the fpu at all. */
242 int copy_thread(int nr, unsigned long clone_flags, unsigned long spu,
243 unsigned long unused, struct task_struct *tsk, struct pt_regs *regs)
245 struct pt_regs *childregs = task_pt_regs(tsk);
246 extern void ret_from_fork(void);
251 childregs->spu = spu;
252 childregs->r0 = 0; /* Child gets zero as return value */
254 tsk->thread.sp = (unsigned long)childregs;
255 tsk->thread.lr = (unsigned long)ret_from_fork;
261 * Capture the user space registers if the task is not running (in user space)
263 int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
269 asmlinkage int sys_fork(unsigned long r0, unsigned long r1, unsigned long r2,
270 unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6,
274 return do_fork(SIGCHLD, regs.spu, ®s, 0, NULL, NULL);
277 #endif /* CONFIG_MMU */
280 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
281 unsigned long parent_tidptr,
282 unsigned long child_tidptr,
283 unsigned long r4, unsigned long r5, unsigned long r6,
289 return do_fork(clone_flags, newsp, ®s, 0,
290 (int __user *)parent_tidptr, (int __user *)child_tidptr);
294 * This is trivial, and on the face of it looks like it
295 * could equally well be done in user mode.
297 * Not so, for quite unobvious reasons - register pressure.
298 * In user mode vfork() cannot have a stack frame, and if
299 * done by calling the "clone()" system call directly, you
300 * do not have enough call-clobbered registers to hold all
301 * the information you need.
303 asmlinkage int sys_vfork(unsigned long r0, unsigned long r1, unsigned long r2,
304 unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6,
307 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.spu, ®s, 0,
312 * sys_execve() executes a new program.
314 asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv,
315 char __user * __user *uenvp,
316 unsigned long r3, unsigned long r4, unsigned long r5,
317 unsigned long r6, struct pt_regs regs)
322 filename = getname(ufilename);
323 error = PTR_ERR(filename);
324 if (IS_ERR(filename))
327 error = do_execve(filename, uargv, uenvp, ®s);
330 current->ptrace &= ~PT_DTRACE;
331 task_unlock(current);
339 * These bracket the sleeping functions..
341 #define first_sched ((unsigned long) scheduling_functions_start_here)
342 #define last_sched ((unsigned long) scheduling_functions_end_here)
344 unsigned long get_wchan(struct task_struct *p)