1 /* $Id: process.c,v 1.28 2004/05/05 16:54:23 lethal Exp $
3 * linux/arch/sh/kernel/process.c
5 * Copyright (C) 1995 Linus Torvalds
7 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
11 * This file handles the architecture-dependent parts of process handling..
14 #include <linux/module.h>
15 #include <linux/unistd.h>
17 #include <linux/elfcore.h>
18 #include <linux/slab.h>
19 #include <linux/a.out.h>
20 #include <linux/ptrace.h>
21 #include <linux/platform.h>
22 #include <linux/kallsyms.h>
25 #include <asm/uaccess.h>
26 #include <asm/mmu_context.h>
28 #if defined(CONFIG_SH_HS7751RVOIP)
29 #include <asm/hs7751rvoip/hs7751rvoip.h>
30 #elif defined(CONFIG_SH_RTS7751R2D)
31 #include <asm/rts7751r2d/rts7751r2d.h>
34 static int hlt_counter=0;
38 #define HARD_IDLE_TIMEOUT (HZ / 3)
40 void disable_hlt(void)
45 EXPORT_SYMBOL(disable_hlt);
52 EXPORT_SYMBOL(enable_hlt);
56 /* endless idle loop with no priority at all */
59 while (!need_resched())
62 while (!need_resched())
66 preempt_enable_no_resched();
72 void machine_restart(char * __unused)
74 /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
75 asm volatile("ldc %0, sr\n\t"
76 "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
79 void machine_halt(void)
81 #if defined(CONFIG_SH_HS7751RVOIP)
84 value = ctrl_inw(PA_OUTPORTR);
85 ctrl_outw((value & 0xffdf), PA_OUTPORTR);
86 #elif defined(CONFIG_SH_RTS7751R2D)
87 ctrl_outw(0x0001, PA_POWOFF);
93 void machine_power_off(void)
95 #if defined(CONFIG_SH_HS7751RVOIP)
98 value = ctrl_inw(PA_OUTPORTR);
99 ctrl_outw((value & 0xffdf), PA_OUTPORTR);
100 #elif defined(CONFIG_SH_RTS7751R2D)
101 ctrl_outw(0x0001, PA_POWOFF);
105 void show_regs(struct pt_regs * regs)
108 printk("Pid : %d, Comm: %20s\n", current->pid, current->comm);
109 print_symbol("PC is at %s\n", regs->pc);
110 printk("PC : %08lx SP : %08lx SR : %08lx ",
111 regs->pc, regs->regs[15], regs->sr);
113 printk("TEA : %08x ", ctrl_inl(MMU_TEA));
117 printk("%s\n", print_tainted());
119 printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
120 regs->regs[0],regs->regs[1],
121 regs->regs[2],regs->regs[3]);
122 printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
123 regs->regs[4],regs->regs[5],
124 regs->regs[6],regs->regs[7]);
125 printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
126 regs->regs[8],regs->regs[9],
127 regs->regs[10],regs->regs[11]);
128 printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
129 regs->regs[12],regs->regs[13],
131 printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
132 regs->mach, regs->macl, regs->gbr, regs->pr);
135 * If we're in kernel mode, dump the stack too..
137 if (!user_mode(regs)) {
138 extern void show_task(unsigned long *sp);
139 unsigned long sp = regs->regs[15];
141 show_task((unsigned long *)sp);
146 * Create a kernel thread
150 * This is the mechanism for creating a new kernel thread.
153 extern void kernel_thread_helper(void);
155 "kernel_thread_helper:\n\t"
164 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
165 { /* Don't use this in BL=1(cli). Or else, CPU resets! */
168 memset(®s, 0, sizeof(regs));
169 regs.regs[4] = (unsigned long) arg;
170 regs.regs[5] = (unsigned long) fn;
172 regs.pc = (unsigned long) kernel_thread_helper;
175 /* Ok, create the new process.. */
176 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL);
180 * Free current thread data structures etc..
182 void exit_thread(void)
184 if (current->thread.ubc_pc) {
185 current->thread.ubc_pc = 0;
190 void flush_thread(void)
192 #if defined(CONFIG_SH_FPU)
193 struct task_struct *tsk = current;
194 /* Forget lazy FPU state */
195 clear_fpu(tsk, task_pt_regs(tsk));
200 void release_thread(struct task_struct *dead_task)
205 /* Fill in the fpu structure for a core dump.. */
206 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
210 #if defined(CONFIG_SH_FPU)
211 struct task_struct *tsk = current;
213 fpvalid = !!tsk_used_math(tsk);
215 unlazy_fpu(tsk, regs);
216 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
224 * Capture the user space registers if the task is not running (in user space)
226 int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
228 struct pt_regs ptregs;
230 ptregs = *task_pt_regs(tsk);
231 elf_core_copy_regs(regs, &ptregs);
237 dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *fpu)
241 #if defined(CONFIG_SH_FPU)
242 fpvalid = !!tsk_used_math(tsk);
244 unlazy_fpu(tsk, task_pt_regs(tsk));
245 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
252 asmlinkage void ret_from_fork(void);
254 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
255 unsigned long unused,
256 struct task_struct *p, struct pt_regs *regs)
258 struct pt_regs *childregs;
259 #if defined(CONFIG_SH_FPU)
260 struct task_struct *tsk = current;
262 unlazy_fpu(tsk, regs);
263 p->thread.fpu = tsk->thread.fpu;
264 copy_to_stopped_child_used_math(p);
267 childregs = task_pt_regs(p);
270 if (user_mode(regs)) {
271 childregs->regs[15] = usp;
273 childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
275 if (clone_flags & CLONE_SETTLS) {
276 childregs->gbr = childregs->regs[0];
278 childregs->regs[0] = 0; /* Set return value for child */
280 p->thread.sp = (unsigned long) childregs;
281 p->thread.pc = (unsigned long) ret_from_fork;
283 p->thread.ubc_pc = 0;
288 /* Tracing by user break controller. */
290 ubc_set_tracing(int asid, unsigned long pc)
292 ctrl_outl(pc, UBC_BARA);
294 /* We don't have any ASID settings for the SH-2! */
295 if (cpu_data->type != CPU_SH7604)
296 ctrl_outb(asid, UBC_BASRA);
298 ctrl_outl(0, UBC_BAMRA);
300 if (cpu_data->type == CPU_SH7729) {
301 ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
302 ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
304 ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
305 ctrl_outw(BRCR_PCBA, UBC_BRCR);
310 * switch_to(x,y) should switch tasks from x to y.
313 struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next)
315 #if defined(CONFIG_SH_FPU)
316 unlazy_fpu(prev, task_pt_regs(prev));
319 #ifdef CONFIG_PREEMPT
322 struct pt_regs *regs;
324 local_irq_save(flags);
325 regs = task_pt_regs(prev);
326 if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
327 int offset = (int)regs->regs[15];
329 /* Reset stack pointer: clear critical region mark */
330 regs->regs[15] = regs->regs[1];
331 if (regs->pc < regs->regs[0])
332 /* Go to rewind point */
333 regs->pc = regs->regs[0] + offset;
335 local_irq_restore(flags);
340 * Restore the kernel mode register
343 asm volatile("ldc %0, r7_bank"
345 : "r" (task_thread_info(next)));
348 /* If no tasks are using the UBC, we're done */
349 if (ubc_usercnt == 0)
350 /* If no tasks are using the UBC, we're done */;
351 else if (next->thread.ubc_pc && next->mm) {
352 ubc_set_tracing(next->mm->context & MMU_CONTEXT_ASID_MASK,
353 next->thread.ubc_pc);
355 ctrl_outw(0, UBC_BBRA);
356 ctrl_outw(0, UBC_BBRB);
363 asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
364 unsigned long r6, unsigned long r7,
368 return do_fork(SIGCHLD, regs.regs[15], ®s, 0, NULL, NULL);
370 /* fork almost works, enough to trick you into looking elsewhere :-( */
375 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
376 unsigned long parent_tidptr,
377 unsigned long child_tidptr,
381 newsp = regs.regs[15];
382 return do_fork(clone_flags, newsp, ®s, 0,
383 (int __user *)parent_tidptr, (int __user *)child_tidptr);
387 * This is trivial, and on the face of it looks like it
388 * could equally well be done in user mode.
390 * Not so, for quite unobvious reasons - register pressure.
391 * In user mode vfork() cannot have a stack frame, and if
392 * done by calling the "clone()" system call directly, you
393 * do not have enough call-clobbered registers to hold all
394 * the information you need.
396 asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
397 unsigned long r6, unsigned long r7,
400 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.regs[15], ®s,
405 * sys_execve() executes a new program.
407 asmlinkage int sys_execve(char *ufilename, char **uargv,
408 char **uenvp, unsigned long r7,
414 filename = getname((char __user *)ufilename);
415 error = PTR_ERR(filename);
416 if (IS_ERR(filename))
419 error = do_execve(filename,
420 (char __user * __user *)uargv,
421 (char __user * __user *)uenvp,
425 current->ptrace &= ~PT_DTRACE;
426 task_unlock(current);
433 unsigned long get_wchan(struct task_struct *p)
435 unsigned long schedule_frame;
438 if (!p || p == current || p->state == TASK_RUNNING)
442 * The same comment as on the Alpha applies here, too ...
444 pc = thread_saved_pc(p);
445 if (in_sched_functions(pc)) {
446 schedule_frame = ((unsigned long *)(long)p->thread.sp)[1];
447 return (unsigned long)((unsigned long *)schedule_frame)[1];
452 asmlinkage void break_point_trap(unsigned long r4, unsigned long r5,
453 unsigned long r6, unsigned long r7,
457 ctrl_outw(0, UBC_BBRA);
458 ctrl_outw(0, UBC_BBRB);
459 current->thread.ubc_pc = 0;
462 force_sig(SIGTRAP, current);
465 asmlinkage void break_point_trap_software(unsigned long r4, unsigned long r5,
466 unsigned long r6, unsigned long r7,
470 force_sig(SIGTRAP, current);