[linux-2.6-block.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/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/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_node(int node)
{
	struct task_struct *p = kmalloc_node(THREAD_SIZE, GFP_KERNEL, node);

	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();
		}

		schedule_preempt_disabled();
	}
}

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)
{
	/* nothing */
}

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() */

/*
 * 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>
1da177e4 LT	19	#include <linux/stddef.h>
	20	#include <linux/unistd.h>
	21	#include <linux/ptrace.h>
	22	#include <linux/slab.h>
	23	#include <linux/user.h>
	24	#include <linux/elf.h>
	25	#include <linux/reboot.h>
	26	#include <linux/interrupt.h>
8defab33	27	#include <linux/pagemap.h>
1da177e4	28
84e8cd6d	29	#include <asm/asm-offsets.h>
1da177e4	30	#include <asm/uaccess.h>
1da177e4 LT	31	#include <asm/setup.h>
1da177e4 LT	32	#include <asm/pgtable.h>
8defab33	33	#include <asm/tlb.h>
1da177e4 LT	34	#include <asm/gdb-stub.h>
	35	#include <asm/mb-regs.h>
	36
	37	#include "local.h"
	38
	39	asmlinkage void ret_from_fork(void);
	40
	41	#include <asm/pgalloc.h>
	42
9dec17eb DH	43	void (*pm_power_off)(void);
	44	EXPORT_SYMBOL(pm_power_off);
	45
504f52b5	46	struct task_struct *alloc_task_struct_node(int node)
1da177e4	47	{
504f52b5 ED	48	struct task_struct *p = kmalloc_node(THREAD_SIZE, GFP_KERNEL, node);
504f52b5 ED	49
1da177e4 LT	50	if (p)
	51	atomic_set((atomic_t *)(p+1), 1);
	52	return p;
	53	}
	54
	55	void free_task_struct(struct task_struct *p)
	56	{
	57	if (atomic_dec_and_test((atomic_t *)(p+1)))
	58	kfree(p);
	59	}
	60
	61	static void core_sleep_idle(void)
	62	{
	63	#ifdef LED_DEBUG_SLEEP
	64	/* Show that we're sleeping... */
	65	__set_LEDS(0x55aa);
	66	#endif
	67	frv_cpu_core_sleep();
	68	#ifdef LED_DEBUG_SLEEP
	69	/* ... and that we woke up */
	70	__set_LEDS(0);
	71	#endif
	72	mb();
	73	}
	74
	75	void (*idle)(void) = core_sleep_idle;
	76
	77	/*
	78	* The idle thread. There's no useful work to be
	79	* done, so just try to conserve power and have a
	80	* low exit latency (ie sit in a loop waiting for
	81	* somebody to say that they'd like to reschedule)
	82	*/
	83	void cpu_idle(void)
	84	{
	85	/* endless idle loop with no priority at all */
	86	while (1) {
	87	while (!need_resched()) {
8defab33 CL	88	check_pgt_cache();
8defab33 CL	89
1da177e4 LT	90	if (!frv_dma_inprogress && idle)
	91	idle();
	92	}
	93
bd2f5536	94	schedule_preempt_disabled();
1da177e4 LT	95	}
	96	}
	97
	98	void machine_restart(char * __unused)
	99	{
	100	unsigned long reset_addr;
	101	#ifdef CONFIG_GDBSTUB
	102	gdbstub_exit(0);
	103	#endif
	104
	105	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
	106	reset_addr = 0xfefff500;
	107	else
	108	reset_addr = 0xfeff0500;
	109
	110	/* Software reset. */
	111	asm volatile(" dcef @(gr0,gr0),1 ! membar !"
	112	" sti %1,@(%0,0) !"
	113	" nop ! nop ! nop ! nop ! nop ! "
	114	" nop ! nop ! nop ! nop ! nop ! "
	115	" nop ! nop ! nop ! nop ! nop ! "
	116	" nop ! nop ! nop ! nop ! nop ! "
	117	: : "r" (reset_addr), "r" (1) );
	118
	119	for (;;)
	120	;
	121	}
	122
	123	void machine_halt(void)
	124	{
	125	#ifdef CONFIG_GDBSTUB
	126	gdbstub_exit(0);
	127	#endif
	128
	129	for (;;);
	130	}
	131
	132	void machine_power_off(void)
	133	{
	134	#ifdef CONFIG_GDBSTUB
	135	gdbstub_exit(0);
	136	#endif
	137
	138	for (;;);
	139	}
	140
	141	void flush_thread(void)
	142	{
adc400f6	143	/* nothing */
1da177e4 LT	144	}
	145
	146	inline unsigned long user_stack(const struct pt_regs *regs)
	147	{
	148	while (regs->next_frame)
	149	regs = regs->next_frame;
	150	return user_mode(regs) ? regs->sp : 0;
	151	}
	152
	153	asmlinkage int sys_fork(void)
	154	{
	155	#ifndef CONFIG_MMU
	156	/* fork almost works, enough to trick you into looking elsewhere:-( */
	157	return -EINVAL;
	158	#else
	159	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
	160	#endif
	161	}
	162
	163	asmlinkage int sys_vfork(void)
	164	{
	165	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, user_stack(__frame), __frame, 0,
	166	NULL, NULL);
	167	}
	168
	169	/*****************************************************************************/
	170	/*
	171	* clone a process
	172	* - tlsptr is retrieved by copy_thread()
	173	*/
	174	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	175	int __user parent_tidptr, int __user child_tidptr,
	176	int __user *tlsptr)
	177	{
	178	if (!newsp)
	179	newsp = user_stack(__frame);
	180	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
	181	} /* end sys_clone() */
	182
1da177e4 LT	183	/*
	184	* set up the kernel stack and exception frames for a new process
	185	*/
6f2c55b8	186	int copy_thread(unsigned long clone_flags,
1da177e4 LT	187	unsigned long usp, unsigned long topstk,
	188	struct task_struct p, struct pt_regs regs)
	189	{
	190	struct pt_regs childregs0, childregs, *regs0;
	191
	192	regs0 = __kernel_frame0_ptr;
	193	childregs0 = (struct pt_regs *)
84e8cd6d	194	(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
1da177e4 LT	195	childregs = childregs0;
	196
	197	/* set up the userspace frame (the only place that the USP is stored) */
	198	childregs0 = regs0;
	199
	200	childregs0->gr8 = 0;
	201	childregs0->sp = usp;
	202	childregs0->next_frame = NULL;
	203
	204	/* set up the return kernel frame if called from kernel_thread() */
	205	if (regs != regs0) {
	206	childregs--;
	207	childregs = regs;
	208	childregs->sp = (unsigned long) childregs0;
	209	childregs->next_frame = childregs0;
097cb338	210	childregs->gr15 = (unsigned long) task_thread_info(p);
1da177e4 LT	211	childregs->gr29 = (unsigned long) p;
	212	}
	213
	214	p->set_child_tid = p->clear_child_tid = NULL;
	215
	216	p->thread.frame = childregs;
	217	p->thread.curr = p;
	218	p->thread.sp = (unsigned long) childregs;
	219	p->thread.fp = 0;
	220	p->thread.lr = 0;
	221	p->thread.pc = (unsigned long) ret_from_fork;
	222	p->thread.frame0 = childregs0;
	223
	224	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
	225	if (clone_flags & CLONE_SETTLS)
	226	childregs->gr29 = childregs->gr12;
	227
	228	save_user_regs(p->thread.user);
	229
	230	return 0;
	231	} /* end copy_thread() */
	232
1da177e4 LT	233	/*
	234	* sys_execve() executes a new program.
	235	*/
d7627467 DH	236	asmlinkage int sys_execve(const char __user *name,
	237	const char __user const __user argv,
	238	const char __user const __user envp)
1da177e4 LT	239	{
	240	int error;
	241	char * filename;
	242
1da177e4 LT	243	filename = getname(name);
	244	error = PTR_ERR(filename);
	245	if (IS_ERR(filename))
b69975a3	246	return error;
1da177e4 LT	247	error = do_execve(filename, argv, envp, __frame);
1da177e4 LT	248	putname(filename);
1da177e4 LT	249	return error;
	250	}
	251
	252	unsigned long get_wchan(struct task_struct *p)
	253	{
	254	struct pt_regs *regs0;
	255	unsigned long fp, pc;
	256	unsigned long stack_limit;
	257	int count = 0;
	258	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	259	return 0;
	260
	261	stack_limit = (unsigned long) (p + 1);
	262	fp = p->thread.fp;
	263	regs0 = p->thread.frame0;
	264
	265	do {
	266	if (fp < stack_limit \|\| fp >= (unsigned long) regs0 \|\| fp & 3)
	267	return 0;
	268
	269	pc = ((unsigned long *) fp)[2];
	270
	271	/* FIXME: This depends on the order of these functions. */
	272	if (!in_sched_functions(pc))
	273	return pc;
	274
	275	fp = (unsigned long ) fp;
	276	} while (count++ < 16);
	277
	278	return 0;
	279	}
	280
	281	unsigned long thread_saved_pc(struct task_struct *tsk)
	282	{
	283	/* Check whether the thread is blocked in resume() */
	284	if (in_sched_functions(tsk->thread.pc))
	285	return ((unsigned long *)tsk->thread.fp)[2];
	286	else
	287	return tsk->thread.pc;
	288	}
	289
	290	int elf_check_arch(const struct elf32_hdr *hdr)
	291	{
	292	unsigned long hsr0 = __get_HSR(0);
	293	unsigned long psr = __get_PSR();
	294
	295	if (hdr->e_machine != EM_FRV)
	296	return 0;
	297
	298	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
	299	case EF_FRV_GPR64:
	300	if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
	301	return 0;
	302	case EF_FRV_GPR32:
	303	case 0:
	304	break;
	305	default:
	306	return 0;
	307	}
	308
	309	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
	310	case EF_FRV_FPR64:
	311	if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
	312	return 0;
313	case EF_FRV_FPR32:
314	case EF_FRV_FPR_NONE:
315	case 0:
316	break;
317	default:
318	return 0;
319	}
320
321	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
322	if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
323	PSR_IMPLE(psr) != PSR_IMPLE_FR451)
324	return 0;
325
326	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
327	case EF_FRV_CPU_GENERIC:
328	break;
329	case EF_FRV_CPU_FR300:
330	case EF_FRV_CPU_SIMPLE:
331	case EF_FRV_CPU_TOMCAT:
332	default:
333	return 0;
334	case EF_FRV_CPU_FR400:
335	if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
336	PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
337	PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
338	PSR_IMPLE(psr) != PSR_IMPLE_FR551)
339	return 0;
340	break;
341	case EF_FRV_CPU_FR450:
342	if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
343	return 0;
344	break;
345	case EF_FRV_CPU_FR500:
346	if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
347	return 0;
348	break;
349	case EF_FRV_CPU_FR550:
350	if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
351	return 0;
352	break;
353	}
354
355	return 1;
356	}
6d8c4e3b DH	357
	358	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpregs)
	359	{
	360	memcpy(fpregs,
	361	&current->thread.user->f,
	362	sizeof(current->thread.user->f));
	363	return 1;
	364	}