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

/* process.c: FRV specific parts of process handling
 *
 * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 * - Derived from arch/m68k/kernel/process.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/errno.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/slab.h>
#include <linux/user.h>
#include <linux/elf.h>
#include <linux/reboot.h>
#include <linux/interrupt.h>
#include <linux/pagemap.h>

#include <asm/asm-offsets.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/setup.h>
#include <asm/pgtable.h>
#include <asm/tlb.h>
#include <asm/gdb-stub.h>
#include <asm/mb-regs.h>

#include "local.h"

asmlinkage void ret_from_fork(void);

#include <asm/pgalloc.h>

void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);

struct task_struct *alloc_task_struct(void)
{
	struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
	if (p)
		atomic_set((atomic_t *)(p+1), 1);
	return p;
}

void free_task_struct(struct task_struct *p)
{
	if (atomic_dec_and_test((atomic_t *)(p+1)))
		kfree(p);
}

static void core_sleep_idle(void)
{
#ifdef LED_DEBUG_SLEEP
	/* Show that we're sleeping... */
	__set_LEDS(0x55aa);
#endif
	frv_cpu_core_sleep();
#ifdef LED_DEBUG_SLEEP
	/* ... and that we woke up */
	__set_LEDS(0);
#endif
	mb();
}

void (*idle)(void) = core_sleep_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()) {
			check_pgt_cache();

			if (!frv_dma_inprogress && idle)
				idle();
		}

		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

void machine_restart(char * __unused)
{
	unsigned long reset_addr;
#ifdef CONFIG_GDBSTUB
	gdbstub_exit(0);
#endif

	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
		reset_addr = 0xfefff500;
	else
		reset_addr = 0xfeff0500;

	/* Software reset. */
	asm volatile("      dcef @(gr0,gr0),1 ! membar !"
		     "      sti     %1,@(%0,0) !"
		     "      nop ! nop ! nop ! nop ! nop ! "
		     "      nop ! nop ! nop ! nop ! nop ! "
		     "      nop ! nop ! nop ! nop ! nop ! "
		     "      nop ! nop ! nop ! nop ! nop ! "
		     : : "r" (reset_addr), "r" (1) );

	for (;;)
		;
}

void machine_halt(void)
{
#ifdef CONFIG_GDBSTUB
	gdbstub_exit(0);
#endif

	for (;;);
}

void machine_power_off(void)
{
#ifdef CONFIG_GDBSTUB
	gdbstub_exit(0);
#endif

	for (;;);
}

void flush_thread(void)
{
#if 0 //ndef NO_FPU
	unsigned long zero = 0;
#endif
	set_fs(USER_DS);
}

inline unsigned long user_stack(const struct pt_regs *regs)
{
	while (regs->next_frame)
		regs = regs->next_frame;
	return user_mode(regs) ? regs->sp : 0;
}

asmlinkage int sys_fork(void)
{
#ifndef CONFIG_MMU
	/* fork almost works, enough to trick you into looking elsewhere:-( */
	return -EINVAL;
#else
	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
#endif
}

asmlinkage int sys_vfork(void)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
		       NULL, NULL);
}

/*****************************************************************************/
/*
 * clone a process
 * - tlsptr is retrieved by copy_thread()
 */
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
			 int __user *parent_tidptr, int __user *child_tidptr,
			 int __user *tlsptr)
{
	if (!newsp)
		newsp = user_stack(__frame);
	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
} /* end sys_clone() */

/*****************************************************************************/
/*
 * This gets called before we allocate a new thread and copy
 * the current task into it.
 */
void prepare_to_copy(struct task_struct *tsk)
{
	//unlazy_fpu(tsk);
} /* end prepare_to_copy() */

/*****************************************************************************/
/*
 * set up the kernel stack and exception frames for a new process
 */
int copy_thread(unsigned long clone_flags,
		unsigned long usp, unsigned long topstk,
		struct task_struct *p, struct pt_regs *regs)
{
	struct pt_regs *childregs0, *childregs, *regs0;

	regs0 = __kernel_frame0_ptr;
	childregs0 = (struct pt_regs *)
		(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
	childregs = childregs0;

	/* set up the userspace frame (the only place that the USP is stored) */
	*childregs0 = *regs0;

	childregs0->gr8		= 0;
	childregs0->sp		= usp;
	childregs0->next_frame	= NULL;

	/* set up the return kernel frame if called from kernel_thread() */
	if (regs != regs0) {
		childregs--;
		*childregs = *regs;
		childregs->sp = (unsigned long) childregs0;
		childregs->next_frame = childregs0;
		childregs->gr15 = (unsigned long) task_thread_info(p);
		childregs->gr29 = (unsigned long) p;
	}

	p->set_child_tid = p->clear_child_tid = NULL;

	p->thread.frame	 = childregs;
	p->thread.curr	 = p;
	p->thread.sp	 = (unsigned long) childregs;
	p->thread.fp	 = 0;
	p->thread.lr	 = 0;
	p->thread.pc	 = (unsigned long) ret_from_fork;
	p->thread.frame0 = childregs0;

	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
	if (clone_flags & CLONE_SETTLS)
		childregs->gr29 = childregs->gr12;

	save_user_regs(p->thread.user);

	return 0;
} /* end copy_thread() */

/*
 * 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;

	filename = getname(name);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		return error;
	error = do_execve(filename, argv, envp, __frame);
	putname(filename);
	return error;
}

unsigned long get_wchan(struct task_struct *p)
{
	struct pt_regs *regs0;
	unsigned long fp, pc;
	unsigned long stack_limit;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	stack_limit = (unsigned long) (p + 1);
	fp = p->thread.fp;
	regs0 = p->thread.frame0;

	do {
		if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
			return 0;

		pc = ((unsigned long *) fp)[2];

		/* FIXME: This depends on the order of these functions. */
		if (!in_sched_functions(pc))
			return pc;

		fp = *(unsigned long *) fp;
	} while (count++ < 16);

	return 0;
}

unsigned long thread_saved_pc(struct task_struct *tsk)
{
	/* Check whether the thread is blocked in resume() */
	if (in_sched_functions(tsk->thread.pc))
		return ((unsigned long *)tsk->thread.fp)[2];
	else
		return tsk->thread.pc;
}

int elf_check_arch(const struct elf32_hdr *hdr)
{
	unsigned long hsr0 = __get_HSR(0);
	unsigned long psr = __get_PSR();

	if (hdr->e_machine != EM_FRV)
		return 0;

	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
	case EF_FRV_GPR64:
		if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
			return 0;
	case EF_FRV_GPR32:
	case 0:
		break;
	default:
		return 0;
	}

	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
	case EF_FRV_FPR64:
		if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
			return 0;
	case EF_FRV_FPR32:
	case EF_FRV_FPR_NONE:
	case 0:
		break;
	default:
		return 0;
	}

	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
		if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
		    PSR_IMPLE(psr) != PSR_IMPLE_FR451)
			return 0;

	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
	case EF_FRV_CPU_GENERIC:
		break;
	case EF_FRV_CPU_FR300:
	case EF_FRV_CPU_SIMPLE:
	case EF_FRV_CPU_TOMCAT:
	default:
		return 0;
	case EF_FRV_CPU_FR400:
		if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
		    PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
		    PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
		    PSR_IMPLE(psr) != PSR_IMPLE_FR551)
			return 0;
		break;
	case EF_FRV_CPU_FR450:
		if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
			return 0;
		break;
	case EF_FRV_CPU_FR500:
		if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
			return 0;
		break;
	case EF_FRV_CPU_FR550:
		if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
			return 0;
		break;
	}

	return 1;
}

int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
{
	memcpy(fpregs,
	       &current->thread.user->f,
	       sizeof(current->thread.user->f));
	return 1;
}
Commit	Line	Data
1da177e4 LT	1	/* process.c: FRV specific parts of process handling
	2	*
	3	* Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	* - Derived from arch/m68k/kernel/process.c
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*/
	12
9dec17eb	13	#include <linux/module.h>
1da177e4 LT	14	#include <linux/errno.h>
	15	#include <linux/sched.h>
	16	#include <linux/kernel.h>
	17	#include <linux/mm.h>
	18	#include <linux/smp.h>
	19	#include <linux/smp_lock.h>
	20	#include <linux/stddef.h>
	21	#include <linux/unistd.h>
	22	#include <linux/ptrace.h>
	23	#include <linux/slab.h>
	24	#include <linux/user.h>
	25	#include <linux/elf.h>
	26	#include <linux/reboot.h>
	27	#include <linux/interrupt.h>
8defab33	28	#include <linux/pagemap.h>
1da177e4	29
84e8cd6d	30	#include <asm/asm-offsets.h>
1da177e4 LT	31	#include <asm/uaccess.h>
	32	#include <asm/system.h>
	33	#include <asm/setup.h>
	34	#include <asm/pgtable.h>
8defab33	35	#include <asm/tlb.h>
1da177e4 LT	36	#include <asm/gdb-stub.h>
	37	#include <asm/mb-regs.h>
	38
	39	#include "local.h"
	40
	41	asmlinkage void ret_from_fork(void);
	42
	43	#include <asm/pgalloc.h>
	44
9dec17eb DH	45	void (*pm_power_off)(void);
	46	EXPORT_SYMBOL(pm_power_off);
	47
1da177e4 LT	48	struct task_struct *alloc_task_struct(void)
	49	{
	50	struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
	51	if (p)
	52	atomic_set((atomic_t *)(p+1), 1);
	53	return p;
	54	}
	55
	56	void free_task_struct(struct task_struct *p)
	57	{
	58	if (atomic_dec_and_test((atomic_t *)(p+1)))
	59	kfree(p);
	60	}
	61
	62	static void core_sleep_idle(void)
	63	{
	64	#ifdef LED_DEBUG_SLEEP
	65	/* Show that we're sleeping... */
	66	__set_LEDS(0x55aa);
	67	#endif
	68	frv_cpu_core_sleep();
	69	#ifdef LED_DEBUG_SLEEP
	70	/* ... and that we woke up */
	71	__set_LEDS(0);
	72	#endif
	73	mb();
	74	}
	75
	76	void (*idle)(void) = core_sleep_idle;
	77
	78	/*
	79	* The idle thread. There's no useful work to be
	80	* done, so just try to conserve power and have a
	81	* low exit latency (ie sit in a loop waiting for
	82	* somebody to say that they'd like to reschedule)
	83	*/
	84	void cpu_idle(void)
	85	{
	86	/* endless idle loop with no priority at all */
	87	while (1) {
	88	while (!need_resched()) {
8defab33 CL	89	check_pgt_cache();
8defab33 CL	90
1da177e4 LT	91	if (!frv_dma_inprogress && idle)
	92	idle();
	93	}
	94
5bfb5d69	95	preempt_enable_no_resched();
1da177e4	96	schedule();
5bfb5d69	97	preempt_disable();
1da177e4 LT	98	}
	99	}
	100
	101	void machine_restart(char * __unused)
	102	{
	103	unsigned long reset_addr;
	104	#ifdef CONFIG_GDBSTUB
	105	gdbstub_exit(0);
	106	#endif
	107
	108	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
	109	reset_addr = 0xfefff500;
	110	else
	111	reset_addr = 0xfeff0500;
	112
	113	/* Software reset. */
	114	asm volatile(" dcef @(gr0,gr0),1 ! membar !"
	115	" sti %1,@(%0,0) !"
	116	" nop ! nop ! nop ! nop ! nop ! "
	117	" nop ! nop ! nop ! nop ! nop ! "
	118	" nop ! nop ! nop ! nop ! nop ! "
	119	" nop ! nop ! nop ! nop ! nop ! "
	120	: : "r" (reset_addr), "r" (1) );
	121
	122	for (;;)
	123	;
	124	}
	125
	126	void machine_halt(void)
	127	{
	128	#ifdef CONFIG_GDBSTUB
	129	gdbstub_exit(0);
	130	#endif
	131
	132	for (;;);
	133	}
	134
	135	void machine_power_off(void)
	136	{
	137	#ifdef CONFIG_GDBSTUB
	138	gdbstub_exit(0);
	139	#endif
	140
	141	for (;;);
	142	}
	143
	144	void flush_thread(void)
	145	{
	146	#if 0 //ndef NO_FPU
	147	unsigned long zero = 0;
	148	#endif
	149	set_fs(USER_DS);
	150	}
	151
	152	inline unsigned long user_stack(const struct pt_regs *regs)
	153	{
	154	while (regs->next_frame)
	155	regs = regs->next_frame;
	156	return user_mode(regs) ? regs->sp : 0;
	157	}
	158
	159	asmlinkage int sys_fork(void)
	160	{
	161	#ifndef CONFIG_MMU
162	/* fork almost works, enough to trick you into looking elsewhere:-( */
163	return -EINVAL;
164	#else
165	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
166	#endif
167	}
168
169	asmlinkage int sys_vfork(void)
170	{
171	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, user_stack(__frame), __frame, 0,
172	NULL, NULL);
173	}
174
175	/*****************************************************************************/
176	/*
177	* clone a process
178	* - tlsptr is retrieved by copy_thread()
179	*/
180	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
181	int __user parent_tidptr, int __user child_tidptr,
182	int __user *tlsptr)
183	{
184	if (!newsp)
185	newsp = user_stack(__frame);
186	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
187	} /* end sys_clone() */
188
189	/*****************************************************************************/
190	/*
191	* This gets called before we allocate a new thread and copy
192	* the current task into it.
193	*/
194	void prepare_to_copy(struct task_struct *tsk)
195	{
196	//unlazy_fpu(tsk);
197	} /* end prepare_to_copy() */
198
199	/*****************************************************************************/
200	/*
201	* set up the kernel stack and exception frames for a new process
202	*/
6f2c55b8	203	int copy_thread(unsigned long clone_flags,
1da177e4 LT	204	unsigned long usp, unsigned long topstk,
	205	struct task_struct p, struct pt_regs regs)
	206	{
	207	struct pt_regs childregs0, childregs, *regs0;
	208
	209	regs0 = __kernel_frame0_ptr;
	210	childregs0 = (struct pt_regs *)
84e8cd6d	211	(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
1da177e4 LT	212	childregs = childregs0;
	213
	214	/* set up the userspace frame (the only place that the USP is stored) */
	215	childregs0 = regs0;
	216
	217	childregs0->gr8 = 0;
	218	childregs0->sp = usp;
	219	childregs0->next_frame = NULL;
	220
	221	/* set up the return kernel frame if called from kernel_thread() */
	222	if (regs != regs0) {
	223	childregs--;
	224	childregs = regs;
	225	childregs->sp = (unsigned long) childregs0;
	226	childregs->next_frame = childregs0;
097cb338	227	childregs->gr15 = (unsigned long) task_thread_info(p);
1da177e4 LT	228	childregs->gr29 = (unsigned long) p;
	229	}
	230
	231	p->set_child_tid = p->clear_child_tid = NULL;
	232
	233	p->thread.frame = childregs;
	234	p->thread.curr = p;
	235	p->thread.sp = (unsigned long) childregs;
	236	p->thread.fp = 0;
	237	p->thread.lr = 0;
	238	p->thread.pc = (unsigned long) ret_from_fork;
	239	p->thread.frame0 = childregs0;
	240
	241	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
	242	if (clone_flags & CLONE_SETTLS)
	243	childregs->gr29 = childregs->gr12;
	244
	245	save_user_regs(p->thread.user);
	246
	247	return 0;
	248	} /* end copy_thread() */
	249
1da177e4 LT	250	/*
	251	* sys_execve() executes a new program.
	252	*/
d7627467 DH	253	asmlinkage int sys_execve(const char __user *name,
	254	const char __user const __user argv,
	255	const char __user const __user envp)
1da177e4 LT	256	{
	257	int error;
	258	char * filename;
	259
1da177e4 LT	260	filename = getname(name);
	261	error = PTR_ERR(filename);
	262	if (IS_ERR(filename))
b69975a3	263	return error;
1da177e4 LT	264	error = do_execve(filename, argv, envp, __frame);
1da177e4 LT	265	putname(filename);
1da177e4 LT	266	return error;
	267	}
	268
	269	unsigned long get_wchan(struct task_struct *p)
	270	{
	271	struct pt_regs *regs0;
	272	unsigned long fp, pc;
	273	unsigned long stack_limit;
	274	int count = 0;
	275	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	276	return 0;
	277
	278	stack_limit = (unsigned long) (p + 1);
	279	fp = p->thread.fp;
	280	regs0 = p->thread.frame0;
	281
	282	do {
	283	if (fp < stack_limit \|\| fp >= (unsigned long) regs0 \|\| fp & 3)
	284	return 0;
	285
	286	pc = ((unsigned long *) fp)[2];
	287
	288	/* FIXME: This depends on the order of these functions. */
	289	if (!in_sched_functions(pc))
	290	return pc;
	291
	292	fp = (unsigned long ) fp;
	293	} while (count++ < 16);
	294
	295	return 0;
	296	}
	297
	298	unsigned long thread_saved_pc(struct task_struct *tsk)
	299	{
	300	/* Check whether the thread is blocked in resume() */
	301	if (in_sched_functions(tsk->thread.pc))
	302	return ((unsigned long *)tsk->thread.fp)[2];
	303	else
	304	return tsk->thread.pc;
	305	}
	306
	307	int elf_check_arch(const struct elf32_hdr *hdr)
	308	{
	309	unsigned long hsr0 = __get_HSR(0);
	310	unsigned long psr = __get_PSR();
	311
	312	if (hdr->e_machine != EM_FRV)
	313	return 0;
	314
	315	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
	316	case EF_FRV_GPR64:
	317	if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
	318	return 0;
	319	case EF_FRV_GPR32:
	320	case 0:
	321	break;
	322	default:
	323	return 0;
	324	}
	325
	326	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
	327	case EF_FRV_FPR64:
	328	if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
	329	return 0;
330	case EF_FRV_FPR32:
331	case EF_FRV_FPR_NONE:
332	case 0:
333	break;
334	default:
335	return 0;
336	}
337
338	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
339	if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
340	PSR_IMPLE(psr) != PSR_IMPLE_FR451)
341	return 0;
342
343	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
344	case EF_FRV_CPU_GENERIC:
345	break;
346	case EF_FRV_CPU_FR300:
347	case EF_FRV_CPU_SIMPLE:
348	case EF_FRV_CPU_TOMCAT:
349	default:
350	return 0;
351	case EF_FRV_CPU_FR400:
352	if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
353	PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
354	PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
355	PSR_IMPLE(psr) != PSR_IMPLE_FR551)
356	return 0;
357	break;
358	case EF_FRV_CPU_FR450:
359	if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
360	return 0;
361	break;
362	case EF_FRV_CPU_FR500:
363	if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
364	return 0;
365	break;
366	case EF_FRV_CPU_FR550:
367	if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
368	return 0;
369	break;
370	}
371
372	return 1;
373	}
6d8c4e3b DH	374
	375	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpregs)
	376	{
	377	memcpy(fpregs,
	378	&current->thread.user->f,
	379	sizeof(current->thread.user->f));
	380	return 1;
	381	}