/* $Id: process.c,v 1.28 2004/05/05 16:54:23 lethal Exp $ * * linux/arch/sh/kernel/process.c * * Copyright (C) 1995 Linus Torvalds * * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima */ /* * This file handles the architecture-dependent parts of process handling.. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(CONFIG_SH_HS7751RVOIP) #include #elif defined(CONFIG_SH_RTS7751R2D) #include #endif static int hlt_counter=0; int ubc_usercnt = 0; #define HARD_IDLE_TIMEOUT (HZ / 3) void disable_hlt(void) { hlt_counter++; } EXPORT_SYMBOL(disable_hlt); void enable_hlt(void) { hlt_counter--; } EXPORT_SYMBOL(enable_hlt); void default_idle(void) { /* endless idle loop with no priority at all */ while (1) { if (hlt_counter) { while (1) if (need_resched()) break; } else { while (!need_resched()) cpu_sleep(); } schedule(); } } void cpu_idle(void) { default_idle(); } void machine_restart(char * __unused) { /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */ asm volatile("ldc %0, sr\n\t" "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001)); } EXPORT_SYMBOL(machine_restart); void machine_halt(void) { #if defined(CONFIG_SH_HS7751RVOIP) unsigned short value; value = ctrl_inw(PA_OUTPORTR); ctrl_outw((value & 0xffdf), PA_OUTPORTR); #elif defined(CONFIG_SH_RTS7751R2D) ctrl_outw(0x0001, PA_POWOFF); #endif while (1) cpu_sleep(); } EXPORT_SYMBOL(machine_halt); void machine_power_off(void) { #if defined(CONFIG_SH_HS7751RVOIP) unsigned short value; value = ctrl_inw(PA_OUTPORTR); ctrl_outw((value & 0xffdf), PA_OUTPORTR); #elif defined(CONFIG_SH_RTS7751R2D) ctrl_outw(0x0001, PA_POWOFF); #endif } EXPORT_SYMBOL(machine_power_off); void show_regs(struct pt_regs * regs) { printk("\n"); printk("Pid : %d, Comm: %20s\n", current->pid, current->comm); print_symbol("PC is at %s\n", regs->pc); printk("PC : %08lx SP : %08lx SR : %08lx ", regs->pc, regs->regs[15], regs->sr); #ifdef CONFIG_MMU printk("TEA : %08x ", ctrl_inl(MMU_TEA)); #else printk(" "); #endif printk("%s\n", print_tainted()); printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n", regs->regs[0],regs->regs[1], regs->regs[2],regs->regs[3]); printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n", regs->regs[4],regs->regs[5], regs->regs[6],regs->regs[7]); printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n", regs->regs[8],regs->regs[9], regs->regs[10],regs->regs[11]); printk("R12 : %08lx R13 : %08lx R14 : %08lx\n", regs->regs[12],regs->regs[13], regs->regs[14]); printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n", regs->mach, regs->macl, regs->gbr, regs->pr); /* * If we're in kernel mode, dump the stack too.. */ if (!user_mode(regs)) { extern void show_task(unsigned long *sp); unsigned long sp = regs->regs[15]; show_task((unsigned long *)sp); } } /* * Create a kernel thread */ /* * This is the mechanism for creating a new kernel thread. * */ extern void kernel_thread_helper(void); __asm__(".align 5\n" "kernel_thread_helper:\n\t" "jsr @r5\n\t" " nop\n\t" "mov.l 1f, r1\n\t" "jsr @r1\n\t" " mov r0, r4\n\t" ".align 2\n\t" "1:.long do_exit"); int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) { /* Don't use this in BL=1(cli). Or else, CPU resets! */ struct pt_regs regs; memset(®s, 0, sizeof(regs)); regs.regs[4] = (unsigned long) arg; regs.regs[5] = (unsigned long) fn; regs.pc = (unsigned long) kernel_thread_helper; regs.sr = (1 << 30); /* Ok, create the new process.. */ return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); } /* * Free current thread data structures etc.. */ void exit_thread(void) { if (current->thread.ubc_pc) { current->thread.ubc_pc = 0; ubc_usercnt -= 1; } } void flush_thread(void) { #if defined(CONFIG_SH_FPU) struct task_struct *tsk = current; struct pt_regs *regs = (struct pt_regs *) ((unsigned long)tsk->thread_info + THREAD_SIZE - sizeof(struct pt_regs) - sizeof(unsigned long)); /* Forget lazy FPU state */ clear_fpu(tsk, regs); clear_used_math(); #endif } void release_thread(struct task_struct *dead_task) { /* do nothing */ } /* Fill in the fpu structure for a core dump.. */ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) { int fpvalid = 0; #if defined(CONFIG_SH_FPU) struct task_struct *tsk = current; fpvalid = !!tsk_used_math(tsk); if (fpvalid) { unlazy_fpu(tsk, regs); memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu)); } #endif return fpvalid; } /* * Capture the user space registers if the task is not running (in user space) */ int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) { struct pt_regs ptregs; ptregs = *(struct pt_regs *) ((unsigned long)tsk->thread_info + THREAD_SIZE - sizeof(struct pt_regs) #ifdef CONFIG_SH_DSP - sizeof(struct pt_dspregs) #endif - sizeof(unsigned long)); elf_core_copy_regs(regs, &ptregs); return 1; } int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *fpu) { int fpvalid = 0; #if defined(CONFIG_SH_FPU) fpvalid = !!tsk_used_math(tsk); if (fpvalid) { struct pt_regs *regs = (struct pt_regs *) ((unsigned long)tsk->thread_info + THREAD_SIZE - sizeof(struct pt_regs) - sizeof(unsigned long)); unlazy_fpu(tsk, regs); memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu)); } #endif return fpvalid; } asmlinkage void ret_from_fork(void); int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, unsigned long unused, struct task_struct *p, struct pt_regs *regs) { struct pt_regs *childregs; #if defined(CONFIG_SH_FPU) struct task_struct *tsk = current; unlazy_fpu(tsk, regs); p->thread.fpu = tsk->thread.fpu; copy_to_stopped_child_used_math(p); #endif childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info) #ifdef CONFIG_SH_DSP - sizeof(struct pt_dspregs) #endif - sizeof(unsigned long)) - 1; *childregs = *regs; if (user_mode(regs)) { childregs->regs[15] = usp; } else { childregs->regs[15] = (unsigned long)p->thread_info + THREAD_SIZE; } if (clone_flags & CLONE_SETTLS) { childregs->gbr = childregs->regs[0]; } childregs->regs[0] = 0; /* Set return value for child */ p->thread.sp = (unsigned long) childregs; p->thread.pc = (unsigned long) ret_from_fork; p->thread.ubc_pc = 0; return 0; } /* * fill in the user structure for a core dump.. */ void dump_thread(struct pt_regs * regs, struct user * dump) { dump->magic = CMAGIC; dump->start_code = current->mm->start_code; dump->start_data = current->mm->start_data; dump->start_stack = regs->regs[15] & ~(PAGE_SIZE - 1); dump->u_tsize = (current->mm->end_code - dump->start_code) >> PAGE_SHIFT; dump->u_dsize = (current->mm->brk + (PAGE_SIZE-1) - dump->start_data) >> PAGE_SHIFT; dump->u_ssize = (current->mm->start_stack - dump->start_stack + PAGE_SIZE - 1) >> PAGE_SHIFT; /* Debug registers will come here. */ dump->regs = *regs; dump->u_fpvalid = dump_fpu(regs, &dump->fpu); } /* Tracing by user break controller. */ static void ubc_set_tracing(int asid, unsigned long pc) { ctrl_outl(pc, UBC_BARA); /* We don't have any ASID settings for the SH-2! */ if (cpu_data->type != CPU_SH7604) ctrl_outb(asid, UBC_BASRA); ctrl_outl(0, UBC_BAMRA); if (cpu_data->type == CPU_SH7729) { ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA); ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR); } else { ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA); ctrl_outw(BRCR_PCBA, UBC_BRCR); } } /* * switch_to(x,y) should switch tasks from x to y. * */ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { #if defined(CONFIG_SH_FPU) struct pt_regs *regs = (struct pt_regs *) ((unsigned long)prev->thread_info + THREAD_SIZE - sizeof(struct pt_regs) - sizeof(unsigned long)); unlazy_fpu(prev, regs); #endif #ifdef CONFIG_PREEMPT { unsigned long flags; struct pt_regs *regs; local_irq_save(flags); regs = (struct pt_regs *) ((unsigned long)prev->thread_info + THREAD_SIZE - sizeof(struct pt_regs) #ifdef CONFIG_SH_DSP - sizeof(struct pt_dspregs) #endif - sizeof(unsigned long)); if (user_mode(regs) && regs->regs[15] >= 0xc0000000) { int offset = (int)regs->regs[15]; /* Reset stack pointer: clear critical region mark */ regs->regs[15] = regs->regs[1]; if (regs->pc < regs->regs[0]) /* Go to rewind point */ regs->pc = regs->regs[0] + offset; } local_irq_restore(flags); } #endif /* * Restore the kernel mode register * k7 (r7_bank1) */ asm volatile("ldc %0, r7_bank" : /* no output */ : "r" (next->thread_info)); #ifdef CONFIG_MMU /* If no tasks are using the UBC, we're done */ if (ubc_usercnt == 0) /* If no tasks are using the UBC, we're done */; else if (next->thread.ubc_pc && next->mm) { ubc_set_tracing(next->mm->context & MMU_CONTEXT_ASID_MASK, next->thread.ubc_pc); } else { ctrl_outw(0, UBC_BBRA); ctrl_outw(0, UBC_BBRB); } #endif return prev; } asmlinkage int sys_fork(unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7, struct pt_regs regs) { #ifdef CONFIG_MMU return do_fork(SIGCHLD, regs.regs[15], ®s, 0, NULL, NULL); #else /* fork almost works, enough to trick you into looking elsewhere :-( */ return -EINVAL; #endif } asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, unsigned long parent_tidptr, unsigned long child_tidptr, struct pt_regs regs) { if (!newsp) newsp = regs.regs[15]; return do_fork(clone_flags, newsp, ®s, 0, (int __user *)parent_tidptr, (int __user *)child_tidptr); } /* * This is trivial, and on the face of it looks like it * could equally well be done in user mode. * * Not so, for quite unobvious reasons - register pressure. * In user mode vfork() cannot have a stack frame, and if * done by calling the "clone()" system call directly, you * do not have enough call-clobbered registers to hold all * the information you need. */ asmlinkage int sys_vfork(unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7, struct pt_regs regs) { return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.regs[15], ®s, 0, NULL, NULL); } /* * sys_execve() executes a new program. */ asmlinkage int sys_execve(char *ufilename, char **uargv, char **uenvp, unsigned long r7, struct pt_regs regs) { int error; char *filename; filename = getname((char __user *)ufilename); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; error = do_execve(filename, (char __user * __user *)uargv, (char __user * __user *)uenvp, ®s); if (error == 0) { task_lock(current); current->ptrace &= ~PT_DTRACE; task_unlock(current); } putname(filename); out: return error; } unsigned long get_wchan(struct task_struct *p) { unsigned long schedule_frame; unsigned long pc; if (!p || p == current || p->state == TASK_RUNNING) return 0; /* * The same comment as on the Alpha applies here, too ... */ pc = thread_saved_pc(p); if (in_sched_functions(pc)) { schedule_frame = ((unsigned long *)(long)p->thread.sp)[1]; return (unsigned long)((unsigned long *)schedule_frame)[1]; } return pc; } asmlinkage void break_point_trap(unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7, struct pt_regs regs) { /* Clear tracing. */ ctrl_outw(0, UBC_BBRA); ctrl_outw(0, UBC_BBRB); current->thread.ubc_pc = 0; ubc_usercnt -= 1; force_sig(SIGTRAP, current); } asmlinkage void break_point_trap_software(unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7, struct pt_regs regs) { regs.pc -= 2; force_sig(SIGTRAP, current); }