[net-next-2.6.git] / arch / h8300 / kernel / process.c

/*
 *  linux/arch/h8300/kernel/process.c
 *
 * Yoshinori Sato <ysato@users.sourceforge.jp>
 *
 *  Based on:
 *
 *  linux/arch/m68knommu/kernel/process.c
 *
 *  Copyright (C) 1998  D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
 *                      Kenneth Albanowski <kjahds@kjahds.com>,
 *                      The Silver Hammer Group, Ltd.
 *
 *  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/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/fs.h>
#include <linux/slab.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/traps.h>
#include <asm/setup.h>
#include <asm/pgtable.h>

void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);

asmlinkage void ret_from_fork(void);

/*
 * The idle loop on an H8/300..
 */
#if !defined(CONFIG_H8300H_SIM) && !defined(CONFIG_H8S_SIM)
static void default_idle(void)
{
	local_irq_disable();
	if (!need_resched()) {
		local_irq_enable();
		/* XXX: race here! What if need_resched() gets set now? */
		__asm__("sleep");
	} else
		local_irq_enable();
}
#else
static void default_idle(void)
{
	cpu_relax();
}
#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)
{
	while (1) {
		while (!need_resched())
			idle();
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

void machine_restart(char * __unused)
{
	local_irq_disable();
	__asm__("jmp @@0"); 
}

void machine_halt(void)
{
	local_irq_disable();
	__asm__("sleep");
	for (;;);
}

void machine_power_off(void)
{
	local_irq_disable();
	__asm__("sleep");
	for (;;);
}

void show_regs(struct pt_regs * regs)
{
	printk("\nPC: %08lx  Status: %02x",
	       regs->pc, regs->ccr);
	printk("\nORIG_ER0: %08lx ER0: %08lx ER1: %08lx",
	       regs->orig_er0, regs->er0, regs->er1);
	printk("\nER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx",
	       regs->er2, regs->er3, regs->er4, regs->er5);
	printk("\nER6' %08lx ",regs->er6);
	if (user_mode(regs))
		printk("USP: %08lx\n", rdusp());
	else
		printk("\n");
}

/*
 * Create a kernel thread
 */
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
	long retval;
	long clone_arg;
	mm_segment_t fs;

	fs = get_fs();
	set_fs (KERNEL_DS);
	clone_arg = flags | CLONE_VM;
	__asm__("mov.l sp,er3\n\t"
		"sub.l er2,er2\n\t"
		"mov.l %2,er1\n\t"
		"mov.l %1,er0\n\t"
		"trapa #0\n\t"
		"cmp.l sp,er3\n\t"
		"beq 1f\n\t"
		"mov.l %4,er0\n\t"
		"mov.l %3,er1\n\t"
		"jsr @er1\n\t"
		"mov.l %5,er0\n\t"
		"trapa #0\n"
		"1:\n\t"
		"mov.l er0,%0"
		:"=r"(retval)
		:"i"(__NR_clone),"g"(clone_arg),"g"(fn),"g"(arg),"i"(__NR_exit)
		:"er0","er1","er2","er3");
	set_fs (fs);
	return retval;
}

void flush_thread(void)
{
}

/*
 * "h8300_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 h8300_fork(struct pt_regs *regs)
{
	return -EINVAL;
}

asmlinkage int h8300_vfork(struct pt_regs *regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
}

asmlinkage int h8300_clone(struct pt_regs *regs)
{
	unsigned long clone_flags;
	unsigned long newsp;

	/* syscall2 puts clone_flags in er1 and usp in er2 */
	clone_flags = regs->er1;
	newsp = regs->er2;
	if (!newsp)
		newsp  = rdusp();
	return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);

}

int copy_thread(unsigned long clone_flags,
                unsigned long usp, unsigned long topstk,
		 struct task_struct * p, struct pt_regs * regs)
{
	struct pt_regs * childregs;

	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;

	*childregs = *regs;
	childregs->retpc = (unsigned long) ret_from_fork;
	childregs->er0 = 0;

	p->thread.usp = usp;
	p->thread.ksp = (unsigned long)childregs;

	return 0;
}

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys_execve(const char *name, char **argv, char **envp,int dummy,...)
{
	int error;
	char * filename;
	struct pt_regs *regs = (struct pt_regs *) ((unsigned char *)&dummy-4);

	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 thread_saved_pc(struct task_struct *tsk)
{
	return ((struct pt_regs *)tsk->thread.esp0)->pc;
}

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)p;
	fp = ((struct pt_regs *)p->thread.ksp)->er6;
	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;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/h8300/kernel/process.c
	3	*
	4	* Yoshinori Sato <ysato@users.sourceforge.jp>
	5	*
	6	* Based on:
	7	*
	8	* linux/arch/m68knommu/kernel/process.c
	9	*
	10	* Copyright (C) 1998 D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
	11	* Kenneth Albanowski <kjahds@kjahds.com>,
	12	* The Silver Hammer Group, Ltd.
	13	*
	14	* linux/arch/m68k/kernel/process.c
	15	*
	16	* Copyright (C) 1995 Hamish Macdonald
	17	*
	18	* 68060 fixes by Jesper Skov
	19	*/
	20
	21	/*
	22	* This file handles the architecture-dependent parts of process handling..
	23	*/
	24
1da177e4 LT	25	#include <linux/errno.h>
	26	#include <linux/module.h>
	27	#include <linux/sched.h>
	28	#include <linux/kernel.h>
	29	#include <linux/mm.h>
	30	#include <linux/smp.h>
	31	#include <linux/smp_lock.h>
	32	#include <linux/stddef.h>
	33	#include <linux/unistd.h>
	34	#include <linux/ptrace.h>
1da177e4	35	#include <linux/user.h>
1da177e4 LT	36	#include <linux/interrupt.h>
1da177e4 LT	37	#include <linux/reboot.h>
0cd82ef1	38	#include <linux/fs.h>
5a0e3ad6	39	#include <linux/slab.h>
1da177e4 LT	40
	41	#include <asm/uaccess.h>
	42	#include <asm/system.h>
	43	#include <asm/traps.h>
	44	#include <asm/setup.h>
	45	#include <asm/pgtable.h>
	46
47f3fc94 AB	47	void (*pm_power_off)(void) = NULL;
	48	EXPORT_SYMBOL(pm_power_off);
	49
1da177e4 LT	50	asmlinkage void ret_from_fork(void);
	51
	52	/*
	53	* The idle loop on an H8/300..
	54	*/
	55	#if !defined(CONFIG_H8300H_SIM) && !defined(CONFIG_H8S_SIM)
cdb04527	56	static void default_idle(void)
1da177e4	57	{
5bfb5d69 NP	58	local_irq_disable();
	59	if (!need_resched()) {
	60	local_irq_enable();
	61	/* XXX: race here! What if need_resched() gets set now? */
	62	__asm__("sleep");
	63	} else
	64	local_irq_enable();
1da177e4 LT	65	}
1da177e4 LT	66	#else
cdb04527	67	static void default_idle(void)
1da177e4	68	{
5bfb5d69	69	cpu_relax();
1da177e4 LT	70	}
	71	#endif
	72	void (*idle)(void) = default_idle;
	73
	74	/*
	75	* The idle thread. There's no useful work to be
	76	* done, so just try to conserve power and have a
	77	* low exit latency (ie sit in a loop waiting for
	78	* somebody to say that they'd like to reschedule)
	79	*/
	80	void cpu_idle(void)
	81	{
5bfb5d69 NP	82	while (1) {
	83	while (!need_resched())
	84	idle();
	85	preempt_enable_no_resched();
	86	schedule();
	87	preempt_disable();
	88	}
1da177e4 LT	89	}
	90
	91	void machine_restart(char * __unused)
	92	{
	93	local_irq_disable();
	94	__asm__("jmp @@0");
	95	}
	96
1da177e4 LT	97	void machine_halt(void)
	98	{
	99	local_irq_disable();
	100	__asm__("sleep");
	101	for (;;);
	102	}
	103
1da177e4 LT	104	void machine_power_off(void)
	105	{
	106	local_irq_disable();
	107	__asm__("sleep");
	108	for (;;);
	109	}
	110
1da177e4 LT	111	void show_regs(struct pt_regs * regs)
	112	{
	113	printk("\nPC: %08lx Status: %02x",
	114	regs->pc, regs->ccr);
	115	printk("\nORIG_ER0: %08lx ER0: %08lx ER1: %08lx",
	116	regs->orig_er0, regs->er0, regs->er1);
	117	printk("\nER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx",
	118	regs->er2, regs->er3, regs->er4, regs->er5);
	119	printk("\nER6' %08lx ",regs->er6);
	120	if (user_mode(regs))
	121	printk("USP: %08lx\n", rdusp());
	122	else
	123	printk("\n");
	124	}
	125
	126	/*
	127	* Create a kernel thread
	128	*/
	129	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	130	{
	131	long retval;
	132	long clone_arg;
	133	mm_segment_t fs;
	134
	135	fs = get_fs();
	136	set_fs (KERNEL_DS);
	137	clone_arg = flags \| CLONE_VM;
	138	__asm__("mov.l sp,er3\n\t"
	139	"sub.l er2,er2\n\t"
	140	"mov.l %2,er1\n\t"
	141	"mov.l %1,er0\n\t"
	142	"trapa #0\n\t"
	143	"cmp.l sp,er3\n\t"
	144	"beq 1f\n\t"
	145	"mov.l %4,er0\n\t"
	146	"mov.l %3,er1\n\t"
	147	"jsr @er1\n\t"
	148	"mov.l %5,er0\n\t"
	149	"trapa #0\n"
	150	"1:\n\t"
	151	"mov.l er0,%0"
	152	:"=r"(retval)
	153	:"i"(__NR_clone),"g"(clone_arg),"g"(fn),"g"(arg),"i"(__NR_exit)
	154	:"er0","er1","er2","er3");
	155	set_fs (fs);
	156	return retval;
	157	}
	158
	159	void flush_thread(void)
	160	{
	161	}
	162
	163	/*
	164	* "h8300_fork()".. By the time we get here, the
	165	* non-volatile registers have also been saved on the
	166	* stack. We do some ugly pointer stuff here.. (see
	167	* also copy_thread)
	168	*/
	169
	170	asmlinkage int h8300_fork(struct pt_regs *regs)
	171	{
	172	return -EINVAL;
	173	}
	174
175	asmlinkage int h8300_vfork(struct pt_regs *regs)
176	{
177	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, rdusp(), regs, 0, NULL, NULL);
178	}
179
180	asmlinkage int h8300_clone(struct pt_regs *regs)
181	{
182	unsigned long clone_flags;
183	unsigned long newsp;
184
185	/* syscall2 puts clone_flags in er1 and usp in er2 */
186	clone_flags = regs->er1;
187	newsp = regs->er2;
188	if (!newsp)
189	newsp = rdusp();
190	return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
191
192	}
193
6f2c55b8	194	int copy_thread(unsigned long clone_flags,
1da177e4 LT	195	unsigned long usp, unsigned long topstk,
	196	struct task_struct * p, struct pt_regs * regs)
	197	{
	198	struct pt_regs * childregs;
	199
68f8b1f8	200	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
1da177e4 LT	201
	202	childregs = regs;
	203	childregs->retpc = (unsigned long) ret_from_fork;
	204	childregs->er0 = 0;
	205
	206	p->thread.usp = usp;
	207	p->thread.ksp = (unsigned long)childregs;
	208
	209	return 0;
	210	}
	211
1da177e4 LT	212	/*
	213	* sys_execve() executes a new program.
	214	*/
c7887325	215	asmlinkage int sys_execve(const char name, char argv, char *envp,int dummy,...)
1da177e4 LT	216	{
	217	int error;
	218	char * filename;
	219	struct pt_regs regs = (struct pt_regs ) ((unsigned char *)&dummy-4);
	220
1da177e4 LT	221	filename = getname(name);
	222	error = PTR_ERR(filename);
	223	if (IS_ERR(filename))
e3c1a6b3	224	return error;
1da177e4 LT	225	error = do_execve(filename, argv, envp, regs);
1da177e4 LT	226	putname(filename);
1da177e4 LT	227	return error;
	228	}
	229
	230	unsigned long thread_saved_pc(struct task_struct *tsk)
	231	{
	232	return ((struct pt_regs *)tsk->thread.esp0)->pc;
	233	}
	234
	235	unsigned long get_wchan(struct task_struct *p)
	236	{
	237	unsigned long fp, pc;
	238	unsigned long stack_page;
	239	int count = 0;
	240	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	241	return 0;
	242
	243	stack_page = (unsigned long)p;
	244	fp = ((struct pt_regs *)p->thread.ksp)->er6;
	245	do {
	246	if (fp < stack_page+sizeof(struct thread_info) \|\|
	247	fp >= 8184+stack_page)
	248	return 0;
	249	pc = ((unsigned long *)fp)[1];
	250	if (!in_sched_functions(pc))
	251	return pc;
	252	fp = (unsigned long ) fp;
	253	} while (count++ < 16);
	254	return 0;
	255	}