diff options
Diffstat (limited to 'arch/m68k/kernel/process.c')
| -rw-r--r-- | arch/m68k/kernel/process.c | 377 | 
1 files changed, 375 insertions, 2 deletions
| diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c index 6cf4bd6e34f8..c54ef927e483 100644 --- a/arch/m68k/kernel/process.c +++ b/arch/m68k/kernel/process.c @@ -1,5 +1,378 @@ +/* + *  linux/arch/m68k/kernel/process.c + * + *  Copyright (C) 1995  Hamish Macdonald + * + *  68060 fixes by Jesper Skov + */ + +/* + * This file handles the architecture-dependent parts of process handling.. + */ + +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/smp.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/reboot.h> +#include <linux/init_task.h> +#include <linux/mqueue.h> + +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/traps.h> +#include <asm/machdep.h> +#include <asm/setup.h> +#include <asm/pgtable.h> + + +asmlinkage void ret_from_fork(void); + + +/* + * Return saved PC from a blocked thread + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ +	struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp; +	/* Check whether the thread is blocked in resume() */ +	if (in_sched_functions(sw->retpc)) +		return ((unsigned long *)sw->a6)[1]; +	else +		return sw->retpc; +} + +/* + * The idle loop on an m68k.. + */ +static void default_idle(void) +{ +	if (!need_resched()) +#if defined(MACH_ATARI_ONLY) +		/* block out HSYNC on the atari (falcon) */ +		__asm__("stop #0x2200" : : : "cc"); +#else +		__asm__("stop #0x2000" : : : "cc"); +#endif +} + +void (*idle)(void) = default_idle; + +/* + * The idle thread. There's no useful work to be + * done, so just try to conserve power and have a + * low exit latency (ie sit in a loop waiting for + * somebody to say that they'd like to reschedule) + */ +void cpu_idle(void) +{ +	/* endless idle loop with no priority at all */ +	while (1) { +		while (!need_resched()) +			idle(); +		schedule_preempt_disabled(); +	} +} + +void machine_restart(char * __unused) +{ +	if (mach_reset) +		mach_reset(); +	for (;;); +} + +void machine_halt(void) +{ +	if (mach_halt) +		mach_halt(); +	for (;;); +} + +void machine_power_off(void) +{ +	if (mach_power_off) +		mach_power_off(); +	for (;;); +} + +void (*pm_power_off)(void) = machine_power_off; +EXPORT_SYMBOL(pm_power_off); + +void show_regs(struct pt_regs * regs) +{ +	printk("\n"); +	printk("Format %02x  Vector: %04x  PC: %08lx  Status: %04x    %s\n", +	       regs->format, regs->vector, regs->pc, regs->sr, print_tainted()); +	printk("ORIG_D0: %08lx  D0: %08lx  A2: %08lx  A1: %08lx\n", +	       regs->orig_d0, regs->d0, regs->a2, regs->a1); +	printk("A0: %08lx  D5: %08lx  D4: %08lx\n", +	       regs->a0, regs->d5, regs->d4); +	printk("D3: %08lx  D2: %08lx  D1: %08lx\n", +	       regs->d3, regs->d2, regs->d1); +	if (!(regs->sr & PS_S)) +		printk("USP: %08lx\n", rdusp()); +} + +/* + * Create a kernel thread + */ +int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) +{ +	int pid; +	mm_segment_t fs; + +	fs = get_fs(); +	set_fs (KERNEL_DS); + +	{ +	register long retval __asm__ ("d0"); +	register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED; + +	retval = __NR_clone; +	__asm__ __volatile__ +	  ("clrl %%d2\n\t" +	   "trap #0\n\t"		/* Linux/m68k system call */ +	   "tstl %0\n\t"		/* child or parent */ +	   "jne 1f\n\t"			/* parent - jump */ +#ifdef CONFIG_MMU +	   "lea %%sp@(%c7),%6\n\t"	/* reload current */ +	   "movel %6@,%6\n\t" +#endif +	   "movel %3,%%sp@-\n\t"	/* push argument */ +	   "jsr %4@\n\t"		/* call fn */ +	   "movel %0,%%d1\n\t"		/* pass exit value */ +	   "movel %2,%%d0\n\t"		/* exit */ +	   "trap #0\n" +	   "1:" +	   : "+d" (retval) +	   : "i" (__NR_clone), "i" (__NR_exit), +	     "r" (arg), "a" (fn), "d" (clone_arg), "r" (current), +	     "i" (-THREAD_SIZE) +	   : "d2"); + +	pid = retval; +	} + +	set_fs (fs); +	return pid; +} +EXPORT_SYMBOL(kernel_thread); + +void flush_thread(void) +{ +	current->thread.fs = __USER_DS; +#ifdef CONFIG_FPU +	if (!FPU_IS_EMU) { +		unsigned long zero = 0; +		asm volatile("frestore %0": :"m" (zero)); +	} +#endif +} + +/* + * "m68k_fork()".. By the time we get here, the + * non-volatile registers have also been saved on the + * stack. We do some ugly pointer stuff here.. (see + * also copy_thread) + */ + +asmlinkage int m68k_fork(struct pt_regs *regs) +{  #ifdef CONFIG_MMU -#include "process_mm.c" +	return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);  #else -#include "process_no.c" +	return -EINVAL;  #endif +} + +asmlinkage int m68k_vfork(struct pt_regs *regs) +{ +	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, +		       NULL, NULL); +} + +asmlinkage int m68k_clone(struct pt_regs *regs) +{ +	unsigned long clone_flags; +	unsigned long newsp; +	int __user *parent_tidptr, *child_tidptr; + +	/* syscall2 puts clone_flags in d1 and usp in d2 */ +	clone_flags = regs->d1; +	newsp = regs->d2; +	parent_tidptr = (int __user *)regs->d3; +	child_tidptr = (int __user *)regs->d4; +	if (!newsp) +		newsp = rdusp(); +	return do_fork(clone_flags, newsp, regs, 0, +		       parent_tidptr, child_tidptr); +} + +int copy_thread(unsigned long clone_flags, unsigned long usp, +		 unsigned long unused, +		 struct task_struct * p, struct pt_regs * regs) +{ +	struct pt_regs * childregs; +	struct switch_stack * childstack, *stack; +	unsigned long *retp; + +	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1; + +	*childregs = *regs; +	childregs->d0 = 0; + +	retp = ((unsigned long *) regs); +	stack = ((struct switch_stack *) retp) - 1; + +	childstack = ((struct switch_stack *) childregs) - 1; +	*childstack = *stack; +	childstack->retpc = (unsigned long)ret_from_fork; + +	p->thread.usp = usp; +	p->thread.ksp = (unsigned long)childstack; + +	if (clone_flags & CLONE_SETTLS) +		task_thread_info(p)->tp_value = regs->d5; + +	/* +	 * Must save the current SFC/DFC value, NOT the value when +	 * the parent was last descheduled - RGH  10-08-96 +	 */ +	p->thread.fs = get_fs().seg; + +#ifdef CONFIG_FPU +	if (!FPU_IS_EMU) { +		/* Copy the current fpu state */ +		asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory"); + +		if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) { +			if (CPU_IS_COLDFIRE) { +				asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t" +					      "fmovel %/fpiar,%1\n\t" +					      "fmovel %/fpcr,%2\n\t" +					      "fmovel %/fpsr,%3" +					      : +					      : "m" (p->thread.fp[0]), +						"m" (p->thread.fpcntl[0]), +						"m" (p->thread.fpcntl[1]), +						"m" (p->thread.fpcntl[2]) +					      : "memory"); +			} else { +				asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t" +					      "fmoveml %/fpiar/%/fpcr/%/fpsr,%1" +					      : +					      : "m" (p->thread.fp[0]), +						"m" (p->thread.fpcntl[0]) +					      : "memory"); +			} +		} + +		/* Restore the state in case the fpu was busy */ +		asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0])); +	} +#endif /* CONFIG_FPU */ + +	return 0; +} + +/* Fill in the fpu structure for a core dump.  */ +#ifdef CONFIG_FPU +int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu) +{ +	char fpustate[216]; + +	if (FPU_IS_EMU) { +		int i; + +		memcpy(fpu->fpcntl, current->thread.fpcntl, 12); +		memcpy(fpu->fpregs, current->thread.fp, 96); +		/* Convert internal fpu reg representation +		 * into long double format +		 */ +		for (i = 0; i < 24; i += 3) +			fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) | +			                 ((fpu->fpregs[i] & 0x0000ffff) << 16); +		return 1; +	} + +	/* First dump the fpu context to avoid protocol violation.  */ +	asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory"); +	if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2]) +		return 0; + +	if (CPU_IS_COLDFIRE) { +		asm volatile ("fmovel %/fpiar,%0\n\t" +			      "fmovel %/fpcr,%1\n\t" +			      "fmovel %/fpsr,%2\n\t" +			      "fmovemd %/fp0-%/fp7,%3" +			      : +			      : "m" (fpu->fpcntl[0]), +				"m" (fpu->fpcntl[1]), +				"m" (fpu->fpcntl[2]), +				"m" (fpu->fpregs[0]) +			      : "memory"); +	} else { +		asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0" +			      : +			      : "m" (fpu->fpcntl[0]) +			      : "memory"); +		asm volatile ("fmovemx %/fp0-%/fp7,%0" +			      : +			      : "m" (fpu->fpregs[0]) +			      : "memory"); +	} + +	return 1; +} +EXPORT_SYMBOL(dump_fpu); +#endif /* CONFIG_FPU */ + +/* + * sys_execve() executes a new program. + */ +asmlinkage int sys_execve(const char __user *name, +			  const char __user *const __user *argv, +			  const char __user *const __user *envp) +{ +	int error; +	char * filename; +	struct pt_regs *regs = (struct pt_regs *) &name; + +	filename = getname(name); +	error = PTR_ERR(filename); +	if (IS_ERR(filename)) +		return error; +	error = do_execve(filename, argv, envp, regs); +	putname(filename); +	return error; +} + +unsigned long get_wchan(struct task_struct *p) +{ +	unsigned long fp, pc; +	unsigned long stack_page; +	int count = 0; +	if (!p || p == current || p->state == TASK_RUNNING) +		return 0; + +	stack_page = (unsigned long)task_stack_page(p); +	fp = ((struct switch_stack *)p->thread.ksp)->a6; +	do { +		if (fp < stack_page+sizeof(struct thread_info) || +		    fp >= 8184+stack_page) +			return 0; +		pc = ((unsigned long *)fp)[1]; +		if (!in_sched_functions(pc)) +			return pc; +		fp = *(unsigned long *) fp; +	} while (count++ < 16); +	return 0; +} | 
