[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/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);

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