[deliverable/linux.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/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_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() */

/*****************************************************************************/
/*
 * 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>
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 LT	30	#include <asm/uaccess.h>
	31	#include <asm/system.h>
	32	#include <asm/setup.h>
	33	#include <asm/pgtable.h>
8defab33	34	#include <asm/tlb.h>
1da177e4 LT	35	#include <asm/gdb-stub.h>
	36	#include <asm/mb-regs.h>
	37
	38	#include "local.h"
	39
	40	asmlinkage void ret_from_fork(void);
	41
	42	#include <asm/pgalloc.h>
	43
9dec17eb DH	44	void (*pm_power_off)(void);
	45	EXPORT_SYMBOL(pm_power_off);
	46
504f52b5	47	struct task_struct *alloc_task_struct_node(int node)
1da177e4	48	{
504f52b5 ED	49	struct task_struct *p = kmalloc_node(THREAD_SIZE, GFP_KERNEL, node);
504f52b5 ED	50
1da177e4 LT	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
bd2f5536	95	schedule_preempt_disabled();
1da177e4 LT	96	}
	97	}
	98
	99	void machine_restart(char * __unused)
	100	{
	101	unsigned long reset_addr;
	102	#ifdef CONFIG_GDBSTUB
	103	gdbstub_exit(0);
	104	#endif
	105
	106	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
	107	reset_addr = 0xfefff500;
	108	else
	109	reset_addr = 0xfeff0500;
	110
	111	/* Software reset. */
	112	asm volatile(" dcef @(gr0,gr0),1 ! membar !"
	113	" sti %1,@(%0,0) !"
	114	" nop ! nop ! nop ! nop ! nop ! "
	115	" nop ! nop ! nop ! nop ! nop ! "
	116	" nop ! nop ! nop ! nop ! nop ! "
	117	" nop ! nop ! nop ! nop ! nop ! "
	118	: : "r" (reset_addr), "r" (1) );
	119
	120	for (;;)
	121	;
	122	}
	123
	124	void machine_halt(void)
	125	{
	126	#ifdef CONFIG_GDBSTUB
	127	gdbstub_exit(0);
	128	#endif
	129
	130	for (;;);
	131	}
	132
	133	void machine_power_off(void)
	134	{
	135	#ifdef CONFIG_GDBSTUB
	136	gdbstub_exit(0);
	137	#endif
	138
	139	for (;;);
	140	}
	141
	142	void flush_thread(void)
	143	{
adc400f6	144	/* nothing */
1da177e4 LT	145	}
	146
	147	inline unsigned long user_stack(const struct pt_regs *regs)
	148	{
	149	while (regs->next_frame)
	150	regs = regs->next_frame;
	151	return user_mode(regs) ? regs->sp : 0;
	152	}
	153
	154	asmlinkage int sys_fork(void)
	155	{
	156	#ifndef CONFIG_MMU
	157	/* fork almost works, enough to trick you into looking elsewhere:-( */
	158	return -EINVAL;
	159	#else
	160	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
	161	#endif
	162	}
	163
	164	asmlinkage int sys_vfork(void)
	165	{
	166	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, user_stack(__frame), __frame, 0,
	167	NULL, NULL);
	168	}
	169
	170	/*****************************************************************************/
	171	/*
	172	* clone a process
	173	* - tlsptr is retrieved by copy_thread()
	174	*/
	175	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	176	int __user parent_tidptr, int __user child_tidptr,
	177	int __user *tlsptr)
	178	{
	179	if (!newsp)
	180	newsp = user_stack(__frame);
	181	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
	182	} /* end sys_clone() */
	183
	184	/*****************************************************************************/
	185	/*
	186	* This gets called before we allocate a new thread and copy
	187	* the current task into it.
	188	*/
	189	void prepare_to_copy(struct task_struct *tsk)
	190	{
	191	//unlazy_fpu(tsk);
	192	} /* end prepare_to_copy() */
	193
	194	/*****************************************************************************/
	195	/*
	196	* set up the kernel stack and exception frames for a new process
	197	*/
6f2c55b8	198	int copy_thread(unsigned long clone_flags,
1da177e4 LT	199	unsigned long usp, unsigned long topstk,
	200	struct task_struct p, struct pt_regs regs)
	201	{
	202	struct pt_regs childregs0, childregs, *regs0;
	203
	204	regs0 = __kernel_frame0_ptr;
	205	childregs0 = (struct pt_regs *)
84e8cd6d	206	(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
1da177e4 LT	207	childregs = childregs0;
	208
	209	/* set up the userspace frame (the only place that the USP is stored) */
	210	childregs0 = regs0;
	211
	212	childregs0->gr8 = 0;
	213	childregs0->sp = usp;
	214	childregs0->next_frame = NULL;
	215
	216	/* set up the return kernel frame if called from kernel_thread() */
	217	if (regs != regs0) {
	218	childregs--;
	219	childregs = regs;
	220	childregs->sp = (unsigned long) childregs0;
	221	childregs->next_frame = childregs0;
097cb338	222	childregs->gr15 = (unsigned long) task_thread_info(p);
1da177e4 LT	223	childregs->gr29 = (unsigned long) p;
	224	}
	225
	226	p->set_child_tid = p->clear_child_tid = NULL;
	227
	228	p->thread.frame = childregs;
	229	p->thread.curr = p;
	230	p->thread.sp = (unsigned long) childregs;
	231	p->thread.fp = 0;
	232	p->thread.lr = 0;
	233	p->thread.pc = (unsigned long) ret_from_fork;
	234	p->thread.frame0 = childregs0;
	235
	236	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
	237	if (clone_flags & CLONE_SETTLS)
	238	childregs->gr29 = childregs->gr12;
	239
	240	save_user_regs(p->thread.user);
	241
	242	return 0;
	243	} /* end copy_thread() */
	244
1da177e4 LT	245	/*
	246	* sys_execve() executes a new program.
	247	*/
d7627467 DH	248	asmlinkage int sys_execve(const char __user *name,
	249	const char __user const __user argv,
	250	const char __user const __user envp)
1da177e4 LT	251	{
	252	int error;
	253	char * filename;
	254
1da177e4 LT	255	filename = getname(name);
	256	error = PTR_ERR(filename);
	257	if (IS_ERR(filename))
b69975a3	258	return error;
1da177e4 LT	259	error = do_execve(filename, argv, envp, __frame);
1da177e4 LT	260	putname(filename);
1da177e4 LT	261	return error;
	262	}
	263
	264	unsigned long get_wchan(struct task_struct *p)
	265	{
	266	struct pt_regs *regs0;
	267	unsigned long fp, pc;
	268	unsigned long stack_limit;
	269	int count = 0;
	270	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	271	return 0;
	272
	273	stack_limit = (unsigned long) (p + 1);
	274	fp = p->thread.fp;
	275	regs0 = p->thread.frame0;
	276
	277	do {
	278	if (fp < stack_limit \|\| fp >= (unsigned long) regs0 \|\| fp & 3)
	279	return 0;
	280
	281	pc = ((unsigned long *) fp)[2];
	282
	283	/* FIXME: This depends on the order of these functions. */
	284	if (!in_sched_functions(pc))
	285	return pc;
	286
	287	fp = (unsigned long ) fp;
	288	} while (count++ < 16);
	289
	290	return 0;
	291	}
	292
	293	unsigned long thread_saved_pc(struct task_struct *tsk)
	294	{
	295	/* Check whether the thread is blocked in resume() */
	296	if (in_sched_functions(tsk->thread.pc))
	297	return ((unsigned long *)tsk->thread.fp)[2];
	298	else
	299	return tsk->thread.pc;
	300	}
	301
	302	int elf_check_arch(const struct elf32_hdr *hdr)
	303	{
	304	unsigned long hsr0 = __get_HSR(0);
	305	unsigned long psr = __get_PSR();
	306
	307	if (hdr->e_machine != EM_FRV)
	308	return 0;
	309
	310	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
	311	case EF_FRV_GPR64:
	312	if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
	313	return 0;
	314	case EF_FRV_GPR32:
	315	case 0:
	316	break;
	317	default:
	318	return 0;
	319	}
	320
	321	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
	322	case EF_FRV_FPR64:
	323	if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
	324	return 0;
325	case EF_FRV_FPR32:
326	case EF_FRV_FPR_NONE:
327	case 0:
328	break;
329	default:
330	return 0;
331	}
332
333	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
334	if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
335	PSR_IMPLE(psr) != PSR_IMPLE_FR451)
336	return 0;
337
338	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
339	case EF_FRV_CPU_GENERIC:
340	break;
341	case EF_FRV_CPU_FR300:
342	case EF_FRV_CPU_SIMPLE:
343	case EF_FRV_CPU_TOMCAT:
344	default:
345	return 0;
346	case EF_FRV_CPU_FR400:
347	if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
348	PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
349	PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
350	PSR_IMPLE(psr) != PSR_IMPLE_FR551)
351	return 0;
352	break;
353	case EF_FRV_CPU_FR450:
354	if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
355	return 0;
356	break;
357	case EF_FRV_CPU_FR500:
358	if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
359	return 0;
360	break;
361	case EF_FRV_CPU_FR550:
362	if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
363	return 0;
364	break;
365	}
366
367	return 1;
368	}
6d8c4e3b DH	369
	370	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpregs)
	371	{
	372	memcpy(fpregs,
	373	&current->thread.user->f,
	374	sizeof(current->thread.user->f));
	375	return 1;
	376	}