[linux-2.6-block.git] / arch / parisc / kernel / process.c

/*
 *    PARISC Architecture-dependent parts of process handling
 *    based on the work for i386
 *
 *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
 *    Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
 *    Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
 *    Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
 *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
 *    Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
 *    Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
 *    Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
 *    Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
 *    Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
 *    Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
 *    Copyright (C) 2001-2014 Helge Deller <deller@gmx.de>
 *    Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
 *
 *
 *    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.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <stdarg.h>

#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/rcupdate.h>
#include <linux/random.h>

#include <asm/io.h>
#include <asm/asm-offsets.h>
#include <asm/assembly.h>
#include <asm/pdc.h>
#include <asm/pdc_chassis.h>
#include <asm/pgalloc.h>
#include <asm/unwind.h>
#include <asm/sections.h>

#define COMMAND_GLOBAL  F_EXTEND(0xfffe0030)
#define CMD_RESET       5       /* reset any module */

/*
** The Wright Brothers and Gecko systems have a H/W problem
** (Lasi...'nuf said) may cause a broadcast reset to lockup
** the system. An HVERSION dependent PDC call was developed
** to perform a "safe", platform specific broadcast reset instead
** of kludging up all the code.
**
** Older machines which do not implement PDC_BROADCAST_RESET will
** return (with an error) and the regular broadcast reset can be
** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
** the PDC call will not return (the system will be reset).
*/
void machine_restart(char *cmd)
{
#ifdef FASTBOOT_SELFTEST_SUPPORT
	/*
	 ** If user has modified the Firmware Selftest Bitmap,
	 ** run the tests specified in the bitmap after the
	 ** system is rebooted w/PDC_DO_RESET.
	 **
	 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	 **
	 ** Using "directed resets" at each processor with the MEM_TOC
	 ** vector cleared will also avoid running destructive
	 ** memory self tests. (Not implemented yet)
	 */
	if (ftc_bitmap) {
		pdc_do_firm_test_reset(ftc_bitmap);
	}
#endif
	/* set up a new led state on systems shipped with a LED State panel */
	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	
	/* "Normal" system reset */
	pdc_do_reset();

	/* Nope...box should reset with just CMD_RESET now */
	gsc_writel(CMD_RESET, COMMAND_GLOBAL);

	/* Wait for RESET to lay us to rest. */
	while (1) ;

}

void machine_halt(void)
{
	/*
	** The LED/ChassisCodes are updated by the led_halt()
	** function, called by the reboot notifier chain.
	*/
}

void (*chassis_power_off)(void);

/*
 * This routine is called from sys_reboot to actually turn off the
 * machine 
 */
void machine_power_off(void)
{
	/* If there is a registered power off handler, call it. */
	if (chassis_power_off)
		chassis_power_off();

	/* Put the soft power button back under hardware control.
	 * If the user had already pressed the power button, the
	 * following call will immediately power off. */
	pdc_soft_power_button(0);
	
	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
		
	/* It seems we have no way to power the system off via
	 * software. The user has to press the button himself. */

	printk(KERN_EMERG "System shut down completed.\n"
	       "Please power this system off now.");
}

void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);

void flush_thread(void)
{
	/* Only needs to handle fpu stuff or perf monitors.
	** REVISIT: several arches implement a "lazy fpu state".
	*/
}

void release_thread(struct task_struct *dead_task)
{
}

/*
 * Fill in the FPU structure for a core dump.
 */

int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
{
	if (regs == NULL)
		return 0;

	memcpy(r, regs->fr, sizeof *r);
	return 1;
}

int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
{
	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	return 1;
}

/*
 * Copy architecture-specific thread state
 */
int
copy_thread(unsigned long clone_flags, unsigned long usp,
	    unsigned long kthread_arg, struct task_struct *p)
{
	struct pt_regs *cregs = &(p->thread.regs);
	void *stack = task_stack_page(p);
	
	/* We have to use void * instead of a function pointer, because
	 * function pointers aren't a pointer to the function on 64-bit.
	 * Make them const so the compiler knows they live in .text */
	extern void * const ret_from_kernel_thread;
	extern void * const child_return;

	if (unlikely(p->flags & PF_KTHREAD)) {
		/* kernel thread */
		memset(cregs, 0, sizeof(struct pt_regs));
		if (!usp) /* idle thread */
			return 0;
		/* Must exit via ret_from_kernel_thread in order
		 * to call schedule_tail()
		 */
		cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
		cregs->kpc = (unsigned long) &ret_from_kernel_thread;
		/*
		 * Copy function and argument to be called from
		 * ret_from_kernel_thread.
		 */
#ifdef CONFIG_64BIT
		cregs->gr[27] = ((unsigned long *)usp)[3];
		cregs->gr[26] = ((unsigned long *)usp)[2];
#else
		cregs->gr[26] = usp;
#endif
		cregs->gr[25] = kthread_arg;
	} else {
		/* user thread */
		/* usp must be word aligned.  This also prevents users from
		 * passing in the value 1 (which is the signal for a special
		 * return for a kernel thread) */
		if (usp) {
			usp = ALIGN(usp, 4);
			if (likely(usp))
				cregs->gr[30] = usp;
		}
		cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
		cregs->kpc = (unsigned long) &child_return;

		/* Setup thread TLS area from the 4th parameter in clone */
		if (clone_flags & CLONE_SETTLS)
			cregs->cr27 = cregs->gr[23];
	}

	return 0;
}

unsigned long thread_saved_pc(struct task_struct *t)
{
	return t->thread.regs.kpc;
}

unsigned long
get_wchan(struct task_struct *p)
{
	struct unwind_frame_info info;
	unsigned long ip;
	int count = 0;

	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	/*
	 * These bracket the sleeping functions..
	 */

	unwind_frame_init_from_blocked_task(&info, p);
	do {
		if (unwind_once(&info) < 0)
			return 0;
		ip = info.ip;
		if (!in_sched_functions(ip))
			return ip;
	} while (count++ < 16);
	return 0;
}

#ifdef CONFIG_64BIT
void *dereference_function_descriptor(void *ptr)
{
	Elf64_Fdesc *desc = ptr;
	void *p;

	if (!probe_kernel_address(&desc->addr, p))
		ptr = p;
	return ptr;
}
#endif

static inline unsigned long brk_rnd(void)
{
	return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT;
}

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());

	if (ret < mm->brk)
		return mm->brk;
	return ret;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* PARISC Architecture-dependent parts of process handling
	3	* based on the work for i386
	4	*
	5	* Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
	6	* Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
	7	* Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
	8	* Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
	9	* Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
	10	* Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
	11	* Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
b2450cc1	12	* Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
1da177e4 LT	13	* Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
	14	* Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
	15	* Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
9dabf60d	16	* Copyright (C) 2001-2014 Helge Deller <deller@gmx.de>
1da177e4 LT	17	* Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
	18	*
	19	*
	20	* This program is free software; you can redistribute it and/or modify
	21	* it under the terms of the GNU General Public License as published by
	22	* the Free Software Foundation; either version 2 of the License, or
	23	* (at your option) any later version.
	24	*
	25	* This program is distributed in the hope that it will be useful,
	26	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	27	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	28	* GNU General Public License for more details.
	29	*
	30	* You should have received a copy of the GNU General Public License
	31	* along with this program; if not, write to the Free Software
	32	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	33	*/
	34
	35	#include <stdarg.h>
	36
	37	#include <linux/elf.h>
	38	#include <linux/errno.h>
	39	#include <linux/kernel.h>
	40	#include <linux/mm.h>
4e950f6f	41	#include <linux/fs.h>
1da177e4 LT	42	#include <linux/module.h>
	43	#include <linux/personality.h>
	44	#include <linux/ptrace.h>
	45	#include <linux/sched.h>
5a0e3ad6	46	#include <linux/slab.h>
1da177e4 LT	47	#include <linux/stddef.h>
	48	#include <linux/unistd.h>
	49	#include <linux/kallsyms.h>
b609308e	50	#include <linux/uaccess.h>
fbe75218	51	#include <linux/rcupdate.h>
9dabf60d	52	#include <linux/random.h>
1da177e4 LT	53
1da177e4 LT	54	#include <asm/io.h>
0013a854	55	#include <asm/asm-offsets.h>
ff0ab8af	56	#include <asm/assembly.h>
1da177e4 LT	57	#include <asm/pdc.h>
	58	#include <asm/pdc_chassis.h>
	59	#include <asm/pgalloc.h>
1da177e4	60	#include <asm/unwind.h>
b609308e	61	#include <asm/sections.h>
1da177e4	62
10992092	63	#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
1da177e4 LT	64	#define CMD_RESET 5 /* reset any module */
	65
	66	/*
	67	** The Wright Brothers and Gecko systems have a H/W problem
	68	** (Lasi...'nuf said) may cause a broadcast reset to lockup
	69	** the system. An HVERSION dependent PDC call was developed
	70	** to perform a "safe", platform specific broadcast reset instead
	71	** of kludging up all the code.
	72	**
	73	** Older machines which do not implement PDC_BROADCAST_RESET will
	74	** return (with an error) and the regular broadcast reset can be
	75	** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
	76	** the PDC call will not return (the system will be reset).
	77	*/
	78	void machine_restart(char *cmd)
	79	{
	80	#ifdef FASTBOOT_SELFTEST_SUPPORT
	81	/*
	82	** If user has modified the Firmware Selftest Bitmap,
	83	** run the tests specified in the bitmap after the
	84	** system is rebooted w/PDC_DO_RESET.
	85	**
	86	** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	87	**
	88	** Using "directed resets" at each processor with the MEM_TOC
	89	** vector cleared will also avoid running destructive
	90	** memory self tests. (Not implemented yet)
	91	*/
	92	if (ftc_bitmap) {
	93	pdc_do_firm_test_reset(ftc_bitmap);
	94	}
	95	#endif
	96	/* set up a new led state on systems shipped with a LED State panel */
	97	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	98
	99	/* "Normal" system reset */
	100	pdc_do_reset();
	101
	102	/* Nope...box should reset with just CMD_RESET now */
	103	gsc_writel(CMD_RESET, COMMAND_GLOBAL);
	104
	105	/* Wait for RESET to lay us to rest. */
	106	while (1) ;
	107
	108	}
	109
1da177e4 LT	110	void machine_halt(void)
	111	{
	112	/*
	113	** The LED/ChassisCodes are updated by the led_halt()
	114	** function, called by the reboot notifier chain.
	115	*/
	116	}
	117
85509c00	118	void (*chassis_power_off)(void);
1da177e4 LT	119
	120	/*
	121	* This routine is called from sys_reboot to actually turn off the
	122	* machine
	123	*/
	124	void machine_power_off(void)
	125	{
	126	/* If there is a registered power off handler, call it. */
85509c00 KM	127	if (chassis_power_off)
85509c00 KM	128	chassis_power_off();
1da177e4 LT	129
	130	/* Put the soft power button back under hardware control.
	131	* If the user had already pressed the power button, the
	132	* following call will immediately power off. */
	133	pdc_soft_power_button(0);
	134
	135	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	136
	137	/* It seems we have no way to power the system off via
	138	* software. The user has to press the button himself. */
	139
	140	printk(KERN_EMERG "System shut down completed.\n"
ad361c98	141	"Please power this system off now.");
1da177e4 LT	142	}
1da177e4 LT	143
85509c00 KM	144	void (*pm_power_off)(void) = machine_power_off;
85509c00 KM	145	EXPORT_SYMBOL(pm_power_off);
1da177e4	146
1da177e4 LT	147	void flush_thread(void)
	148	{
	149	/* Only needs to handle fpu stuff or perf monitors.
	150	** REVISIT: several arches implement a "lazy fpu state".
	151	*/
1da177e4 LT	152	}
	153
	154	void release_thread(struct task_struct *dead_task)
	155	{
	156	}
	157
	158	/*
	159	* Fill in the FPU structure for a core dump.
	160	*/
	161
	162	int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
	163	{
	164	if (regs == NULL)
	165	return 0;
	166
	167	memcpy(r, regs->fr, sizeof *r);
	168	return 1;
	169	}
	170
	171	int dump_task_fpu (struct task_struct tsk, elf_fpregset_t r)
	172	{
	173	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	174	return 1;
	175	}
	176
5fec97d0 AD	177	/*
	178	* Copy architecture-specific thread state
	179	*/
1da177e4	180	int
6f2c55b8	181	copy_thread(unsigned long clone_flags, unsigned long usp,
5fec97d0	182	unsigned long kthread_arg, struct task_struct *p)
1da177e4	183	{
afa86fc4	184	struct pt_regs *cregs = &(p->thread.regs);
40f1f0de	185	void *stack = task_stack_page(p);
1da177e4 LT	186
	187	/* We have to use void * instead of a function pointer, because
	188	* function pointers aren't a pointer to the function on 64-bit.
	189	* Make them const so the compiler knows they live in .text */
	190	extern void * const ret_from_kernel_thread;
	191	extern void * const child_return;
c78c2b7e	192
ff0ab8af	193	if (unlikely(p->flags & PF_KTHREAD)) {
5fec97d0	194	/* kernel thread */
a44e060f	195	memset(cregs, 0, sizeof(struct pt_regs));
ff0ab8af AV	196	if (!usp) /* idle thread */
ff0ab8af AV	197	return 0;
1da177e4 LT	198	/* Must exit via ret_from_kernel_thread in order
	199	* to call schedule_tail()
	200	*/
ff0ab8af	201	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
1da177e4 LT	202	cregs->kpc = (unsigned long) &ret_from_kernel_thread;
	203	/*
	204	* Copy function and argument to be called from
	205	* ret_from_kernel_thread.
	206	*/
a8f44e38	207	#ifdef CONFIG_64BIT
a44e060f AV	208	cregs->gr[27] = ((unsigned long *)usp)[3];
	209	cregs->gr[26] = ((unsigned long *)usp)[2];
	210	#else
	211	cregs->gr[26] = usp;
1da177e4	212	#endif
5fec97d0	213	cregs->gr[25] = kthread_arg;
1da177e4 LT	214	} else {
1da177e4 LT	215	/* user thread */
415bfae9 AV	216	/* usp must be word aligned. This also prevents users from
	217	* passing in the value 1 (which is the signal for a special
	218	* return for a kernel thread) */
	219	if (usp) {
	220	usp = ALIGN(usp, 4);
	221	if (likely(usp))
	222	cregs->gr[30] = usp;
	223	}
ff0ab8af	224	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
c78c2b7e HD	225	cregs->kpc = (unsigned long) &child_return;
c78c2b7e HD	226
b2450cc1 CD	227	/* Setup thread TLS area from the 4th parameter in clone */
b2450cc1 CD	228	if (clone_flags & CLONE_SETTLS)
415bfae9	229	cregs->cr27 = cregs->gr[23];
1da177e4 LT	230	}
	231
	232	return 0;
	233	}
	234
	235	unsigned long thread_saved_pc(struct task_struct *t)
	236	{
	237	return t->thread.regs.kpc;
	238	}
	239
3db03b4a	240	unsigned long
1da177e4 LT	241	get_wchan(struct task_struct *p)
	242	{
	243	struct unwind_frame_info info;
	244	unsigned long ip;
	245	int count = 0;
cc650a7a KM	246
	247	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	248	return 0;
	249
1da177e4 LT	250	/*
	251	* These bracket the sleeping functions..
	252	*/
	253
	254	unwind_frame_init_from_blocked_task(&info, p);
	255	do {
	256	if (unwind_once(&info) < 0)
	257	return 0;
	258	ip = info.ip;
	259	if (!in_sched_functions(ip))
	260	return ip;
	261	} while (count++ < 16);
	262	return 0;
	263	}
b609308e KM	264
	265	#ifdef CONFIG_64BIT
	266	void dereference_function_descriptor(void ptr)
	267	{
	268	Elf64_Fdesc *desc = ptr;
	269	void *p;
	270
	271	if (!probe_kernel_address(&desc->addr, p))
	272	ptr = p;
	273	return ptr;
	274	}
	275	#endif
9dabf60d HD	276
	277	static inline unsigned long brk_rnd(void)
	278	{
18d98a79	279	return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT;
9dabf60d HD	280	}
	281
	282	unsigned long arch_randomize_brk(struct mm_struct *mm)
	283	{
	284	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
	285
	286	if (ret < mm->brk)
	287	return mm->brk;
	288	return ret;
	289	}