[mirror_ubuntu-zesty-kernel.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(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>
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
1da177e4 LT	47	struct task_struct *alloc_task_struct(void)
	48	{
	49	struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
	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
5bfb5d69	94	preempt_enable_no_resched();
1da177e4	95	schedule();
5bfb5d69	96	preempt_disable();
1da177e4 LT	97	}
	98	}
	99
	100	void machine_restart(char * __unused)
	101	{
	102	unsigned long reset_addr;
	103	#ifdef CONFIG_GDBSTUB
	104	gdbstub_exit(0);
	105	#endif
	106
	107	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
	108	reset_addr = 0xfefff500;
	109	else
	110	reset_addr = 0xfeff0500;
	111
	112	/* Software reset. */
	113	asm volatile(" dcef @(gr0,gr0),1 ! membar !"
	114	" sti %1,@(%0,0) !"
	115	" nop ! nop ! nop ! nop ! nop ! "
	116	" nop ! nop ! nop ! nop ! nop ! "
	117	" nop ! nop ! nop ! nop ! nop ! "
	118	" nop ! nop ! nop ! nop ! nop ! "
	119	: : "r" (reset_addr), "r" (1) );
	120
	121	for (;;)
	122	;
	123	}
	124
	125	void machine_halt(void)
	126	{
	127	#ifdef CONFIG_GDBSTUB
	128	gdbstub_exit(0);
	129	#endif
	130
	131	for (;;);
	132	}
	133
	134	void machine_power_off(void)
	135	{
	136	#ifdef CONFIG_GDBSTUB
	137	gdbstub_exit(0);
	138	#endif
	139
	140	for (;;);
	141	}
	142
	143	void flush_thread(void)
	144	{
	145	#if 0 //ndef NO_FPU
	146	unsigned long zero = 0;
	147	#endif
	148	set_fs(USER_DS);
	149	}
	150
	151	inline unsigned long user_stack(const struct pt_regs *regs)
	152	{
	153	while (regs->next_frame)
	154	regs = regs->next_frame;
	155	return user_mode(regs) ? regs->sp : 0;
	156	}
	157
	158	asmlinkage int sys_fork(void)
	159	{
	160	#ifndef CONFIG_MMU
161	/* fork almost works, enough to trick you into looking elsewhere:-( */
162	return -EINVAL;
163	#else
164	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
165	#endif
166	}
167
168	asmlinkage int sys_vfork(void)
169	{
170	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, user_stack(__frame), __frame, 0,
171	NULL, NULL);
172	}
173
174	/*****************************************************************************/
175	/*
176	* clone a process
177	* - tlsptr is retrieved by copy_thread()
178	*/
179	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
180	int __user parent_tidptr, int __user child_tidptr,
181	int __user *tlsptr)
182	{
183	if (!newsp)
184	newsp = user_stack(__frame);
185	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
186	} /* end sys_clone() */
187
188	/*****************************************************************************/
189	/*
190	* This gets called before we allocate a new thread and copy
191	* the current task into it.
192	*/
193	void prepare_to_copy(struct task_struct *tsk)
194	{
195	//unlazy_fpu(tsk);
196	} /* end prepare_to_copy() */
197
198	/*****************************************************************************/
199	/*
200	* set up the kernel stack and exception frames for a new process
201	*/
6f2c55b8	202	int copy_thread(unsigned long clone_flags,
1da177e4 LT	203	unsigned long usp, unsigned long topstk,
	204	struct task_struct p, struct pt_regs regs)
	205	{
	206	struct pt_regs childregs0, childregs, *regs0;
	207
	208	regs0 = __kernel_frame0_ptr;
	209	childregs0 = (struct pt_regs *)
84e8cd6d	210	(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
1da177e4 LT	211	childregs = childregs0;
	212
	213	/* set up the userspace frame (the only place that the USP is stored) */
	214	childregs0 = regs0;
	215
	216	childregs0->gr8 = 0;
	217	childregs0->sp = usp;
	218	childregs0->next_frame = NULL;
	219
	220	/* set up the return kernel frame if called from kernel_thread() */
	221	if (regs != regs0) {
	222	childregs--;
	223	childregs = regs;
	224	childregs->sp = (unsigned long) childregs0;
	225	childregs->next_frame = childregs0;
097cb338	226	childregs->gr15 = (unsigned long) task_thread_info(p);
1da177e4 LT	227	childregs->gr29 = (unsigned long) p;
	228	}
	229
	230	p->set_child_tid = p->clear_child_tid = NULL;
	231
	232	p->thread.frame = childregs;
	233	p->thread.curr = p;
	234	p->thread.sp = (unsigned long) childregs;
	235	p->thread.fp = 0;
	236	p->thread.lr = 0;
	237	p->thread.pc = (unsigned long) ret_from_fork;
	238	p->thread.frame0 = childregs0;
	239
	240	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
	241	if (clone_flags & CLONE_SETTLS)
	242	childregs->gr29 = childregs->gr12;
	243
	244	save_user_regs(p->thread.user);
	245
	246	return 0;
	247	} /* end copy_thread() */
	248
1da177e4 LT	249	/*
	250	* sys_execve() executes a new program.
	251	*/
d7627467 DH	252	asmlinkage int sys_execve(const char __user *name,
	253	const char __user const __user argv,
	254	const char __user const __user envp)
1da177e4 LT	255	{
	256	int error;
	257	char * filename;
	258
1da177e4 LT	259	filename = getname(name);
	260	error = PTR_ERR(filename);
	261	if (IS_ERR(filename))
b69975a3	262	return error;
1da177e4 LT	263	error = do_execve(filename, argv, envp, __frame);
1da177e4 LT	264	putname(filename);
1da177e4 LT	265	return error;
	266	}
	267
	268	unsigned long get_wchan(struct task_struct *p)
	269	{
	270	struct pt_regs *regs0;
	271	unsigned long fp, pc;
	272	unsigned long stack_limit;
	273	int count = 0;
	274	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	275	return 0;
	276
	277	stack_limit = (unsigned long) (p + 1);
	278	fp = p->thread.fp;
	279	regs0 = p->thread.frame0;
	280
	281	do {
	282	if (fp < stack_limit \|\| fp >= (unsigned long) regs0 \|\| fp & 3)
	283	return 0;
	284
	285	pc = ((unsigned long *) fp)[2];
	286
	287	/* FIXME: This depends on the order of these functions. */
	288	if (!in_sched_functions(pc))
	289	return pc;
	290
	291	fp = (unsigned long ) fp;
	292	} while (count++ < 16);
	293
	294	return 0;
	295	}
	296
	297	unsigned long thread_saved_pc(struct task_struct *tsk)
	298	{
	299	/* Check whether the thread is blocked in resume() */
	300	if (in_sched_functions(tsk->thread.pc))
	301	return ((unsigned long *)tsk->thread.fp)[2];
	302	else
	303	return tsk->thread.pc;
	304	}
	305
	306	int elf_check_arch(const struct elf32_hdr *hdr)
	307	{
	308	unsigned long hsr0 = __get_HSR(0);
	309	unsigned long psr = __get_PSR();
	310
	311	if (hdr->e_machine != EM_FRV)
	312	return 0;
	313
	314	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
	315	case EF_FRV_GPR64:
	316	if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
	317	return 0;
	318	case EF_FRV_GPR32:
	319	case 0:
	320	break;
	321	default:
	322	return 0;
	323	}
	324
	325	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
	326	case EF_FRV_FPR64:
	327	if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
	328	return 0;
329	case EF_FRV_FPR32:
330	case EF_FRV_FPR_NONE:
331	case 0:
332	break;
333	default:
334	return 0;
335	}
336
337	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
338	if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
339	PSR_IMPLE(psr) != PSR_IMPLE_FR451)
340	return 0;
341
342	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
343	case EF_FRV_CPU_GENERIC:
344	break;
345	case EF_FRV_CPU_FR300:
346	case EF_FRV_CPU_SIMPLE:
347	case EF_FRV_CPU_TOMCAT:
348	default:
349	return 0;
350	case EF_FRV_CPU_FR400:
351	if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
352	PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
353	PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
354	PSR_IMPLE(psr) != PSR_IMPLE_FR551)
355	return 0;
356	break;
357	case EF_FRV_CPU_FR450:
358	if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
359	return 0;
360	break;
361	case EF_FRV_CPU_FR500:
362	if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
363	return 0;
364	break;
365	case EF_FRV_CPU_FR550:
366	if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
367	return 0;
368	break;
369	}
370
371	return 1;
372	}
6d8c4e3b DH	373
	374	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpregs)
	375	{
	376	memcpy(fpregs,
	377	&current->thread.user->f,
	378	sizeof(current->thread.user->f));
	379	return 1;
	380	}