/* * arch/sh/kernel/process.c * * This file handles the architecture-dependent parts of process handling.. * *  Copyright (C) 1995  Linus Torvalds * *  SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima *		     Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC *		     Copyright (C) 2002 - 2006  Paul Mundt */#include <linux/module.h>#include <linux/mm.h>#include <linux/elfcore.h>#include <linux/pm.h>#include <linux/kallsyms.h>#include <linux/kexec.h>#include <asm/uaccess.h>#include <asm/mmu_context.h>#include <asm/ubc.h> static int hlt_counter;int ubc_usercnt = 0; #define HARD_IDLE_TIMEOUT (HZ / 3) void (*pm_idle)(void);void (*pm_power_off)(void);EXPORT_SYMBOL(pm_power_off); void disable_hlt(void){	hlt_counter++;}EXPORT_SYMBOL(disable_hlt); void enable_hlt(void){	hlt_counter--;}EXPORT_SYMBOL(enable_hlt); void default_idle(void){	if (!hlt_counter)		cpu_sleep();	else		cpu_relax();} void cpu_idle(void){	/* endless idle loop with no priority at all */	while (1) {		void (*idle)(void) = pm_idle; 		if (!idle)			idle = default_idle; 		while (!need_resched())			idle(); 		preempt_enable_no_resched();		schedule();		preempt_disable();	}} 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));} void machine_halt(void){	local_irq_disable(); 	while (1)		cpu_sleep();} void machine_power_off(void){	if (pm_power_off)		pm_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", instruction_pointer(regs));	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); 	show_trace(NULL, (unsigned long *)regs->regs[15], regs);} /* * 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"); /* Don't use this in BL=1(cli).  Or else, CPU resets! */int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags){	struct pt_regs regs; 	memset(&regs, 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,		       &regs, 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;	/* Forget lazy FPU state */	clear_fpu(tsk, task_pt_regs(tsk));	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 = *task_pt_regs(tsk);	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) {		unlazy_fpu(tsk, task_pt_regs(tsk));		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 thread_info *ti = task_thread_info(p);	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 = task_pt_regs(p);	*childregs = *regs; 	if (user_mode(regs)) {		childregs->regs[15] = usp;		ti->addr_limit = USER_DS;	} else {		childregs->regs[15] = (unsigned long)childregs;		ti->addr_limit = KERNEL_DS;	} 	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;} /* Tracing by user break controller.  */static void ubc_set_tracing(int asid, unsigned long pc){#if defined(CONFIG_CPU_SH4A)	unsigned long val; 	val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);	val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid)); 	ctrl_outl(val, UBC_CBR0);	ctrl_outl(pc,  UBC_CAR0);	ctrl_outl(0x0, UBC_CAMR0);	ctrl_outl(0x0, UBC_CBCR); 	val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);	ctrl_outl(val, UBC_CRR0); 	/* Read UBC register that we wrote last, for checking update */	val = ctrl_inl(UBC_CRR0); #else	/* CONFIG_CPU_SH4A */	ctrl_outl(pc, UBC_BARA); #ifdef CONFIG_MMU	/* We don't have any ASID settings for the SH-2! */	if (current_cpu_data.type != CPU_SH7604)		ctrl_outb(asid, UBC_BASRA);#endif 	ctrl_outl(0, UBC_BAMRA); 	if (current_cpu_data.type == CPU_SH7729 ||	    current_cpu_data.type == CPU_SH7710) {		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);	}#endif	/* CONFIG_CPU_SH4A */} /* *	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)	unlazy_fpu(prev, task_pt_regs(prev));#endif #ifdef CONFIG_PREEMPT	{		unsigned long flags;		struct pt_regs *regs; 		local_irq_save(flags);		regs = task_pt_regs(prev);		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 #ifdef CONFIG_MMU	/*	 * Restore the kernel mode register	 *	k7 (r7_bank1)	 */	asm volatile("ldc	%0, r7_bank"		     : /* no output */		     : "r" (task_thread_info(next)));#endif 	/* 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) {		int asid = 0;#ifdef CONFIG_MMU		asid |= cpu_asid(smp_processor_id(), next->mm);#endif		ubc_set_tracing(asid, next->thread.ubc_pc);	} else {#if defined(CONFIG_CPU_SH4A)		ctrl_outl(UBC_CBR_INIT, UBC_CBR0);		ctrl_outl(UBC_CRR_INIT, UBC_CRR0);#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){	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);#ifdef CONFIG_MMU	return do_fork(SIGCHLD, regs->regs[15], regs, 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){	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);	if (!newsp)		newsp = regs->regs[15];	return do_fork(clone_flags, newsp, regs, 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){	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,		       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){	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);	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,			  regs);	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)p->thread.sp;		return ((unsigned long *)schedule_frame)[21];	} 	return pc;} asmlinkage void break_point_trap(void){	/* Clear tracing.  */#if defined(CONFIG_CPU_SH4A)	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);#else	ctrl_outw(0, UBC_BBRA);	ctrl_outw(0, UBC_BBRB);#endif	current->thread.ubc_pc = 0;	ubc_usercnt -= 1; 	force_sig(SIGTRAP, current);} /* * Generic trap handler. */asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5,				   unsigned long r6, unsigned long r7,				   struct pt_regs __regs){	struct pt_regs *regs = RELOC_HIDE(&__regs, 0); 	/* Rewind */	regs->pc -= 2; 	force_sig(SIGTRAP, current);} 

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