[thirdparty/kernel/stable.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-lixux.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) 2001-2002 Helge Deller <deller at parisc-linux.org>
 *    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/module.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/kallsyms.h>

#include <asm/io.h>
#include <asm/offsets.h>
#include <asm/pdc.h>
#include <asm/pdc_chassis.h>
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm/unwind.h>

static int hlt_counter;

/*
 * Power off function, if any
 */ 
void (*pm_power_off)(void);

void disable_hlt(void)
{
	hlt_counter++;
}

EXPORT_SYMBOL(disable_hlt);

void enable_hlt(void)
{
	hlt_counter--;
}

EXPORT_SYMBOL(enable_hlt);

void default_idle(void)
{
	barrier();
}

/*
 * 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())
			barrier();
		schedule();
		check_pgt_cache();
	}
}


#ifdef __LP64__
#define COMMAND_GLOBAL  0xfffffffffffe0030UL
#else
#define COMMAND_GLOBAL  0xfffe0030
#endif

#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.
	*/
}


/*
 * 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(pm_power_off)
		pm_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"
	       KERN_EMERG "Please power this system off now.");
}


/*
 * Create a kernel thread
 */

extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{

	/*
	 * FIXME: Once we are sure we don't need any debug here,
	 *	  kernel_thread can become a #define.
	 */

	return __kernel_thread(fn, arg, flags);
}
EXPORT_SYMBOL(kernel_thread);

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
}

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

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;
}

/* Note that "fork()" is implemented in terms of clone, with
   parameters (SIGCHLD, regs->gr[30], regs). */
int
sys_clone(unsigned long clone_flags, unsigned long usp,
	  struct pt_regs *regs)
{
	int __user *user_tid = (int __user *)regs->gr[26];

	/* 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) */
	usp = ALIGN(usp, 4);

	/* A zero value for usp means use the current stack */
	if(usp == 0)
		usp = regs->gr[30];

	return do_fork(clone_flags, usp, regs, 0, user_tid, NULL);
}

int
sys_vfork(struct pt_regs *regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
}

int
copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	    unsigned long unused,	/* in ia64 this is "user_stack_size" */
	    struct task_struct * p, struct pt_regs * pregs)
{
	struct pt_regs * cregs = &(p->thread.regs);
	struct thread_info *ti = p->thread_info;
	
	/* 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;
#ifdef CONFIG_HPUX
	extern void * const hpux_child_return;
#endif

	*cregs = *pregs;

	/* Set the return value for the child.  Note that this is not
           actually restored by the syscall exit path, but we put it
           here for consistency in case of signals. */
	cregs->gr[28] = 0; /* child */

	/*
	 * We need to differentiate between a user fork and a
	 * kernel fork. We can't use user_mode, because the
	 * the syscall path doesn't save iaoq. Right now
	 * We rely on the fact that kernel_thread passes
	 * in zero for usp.
	 */
	if (usp == 1) {
		/* kernel thread */
		cregs->ksp = (((unsigned long)(ti)) + THREAD_SZ_ALGN);
		/* Must exit via ret_from_kernel_thread in order
		 * to call schedule_tail()
		 */
		cregs->kpc = (unsigned long) &ret_from_kernel_thread;
		/*
		 * Copy function and argument to be called from
		 * ret_from_kernel_thread.
		 */
#ifdef __LP64__
		cregs->gr[27] = pregs->gr[27];
#endif
		cregs->gr[26] = pregs->gr[26];
		cregs->gr[25] = pregs->gr[25];
	} else {
		/* user thread */
		/*
		 * Note that the fork wrappers are responsible
		 * for setting gr[21].
		 */

		/* Use same stack depth as parent */
		cregs->ksp = ((unsigned long)(ti))
			+ (pregs->gr[21] & (THREAD_SIZE - 1));
		cregs->gr[30] = usp;
		if (p->personality == PER_HPUX) {
#ifdef CONFIG_HPUX
			cregs->kpc = (unsigned long) &hpux_child_return;
#else
			BUG();
#endif
		} else {
			cregs->kpc = (unsigned long) &child_return;
		}
	}

	return 0;
}

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

/*
 * sys_execve() executes a new program.
 */

asmlinkage int sys_execve(struct pt_regs *regs)
{
	int error;
	char *filename;

	filename = getname((const char __user *) regs->gr[26]);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;
	error = do_execve(filename, (char __user **) regs->gr[25],
		(char __user **) regs->gr[24], regs);
	if (error == 0) {
		task_lock(current);
		current->ptrace &= ~PT_DTRACE;
		task_unlock(current);
	}
	putname(filename);
out:

	return error;
}

unsigned long 
get_wchan(struct task_struct *p)
{
	struct unwind_frame_info info;
	unsigned long ip;
	int count = 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;
}
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>
	12	* Copyright (C) 2000 Richard Hirst <rhirst with parisc-lixux.org>
	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>
	16	* Copyright (C) 2001-2002 Helge Deller <deller at parisc-linux.org>
	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>
	41	#include <linux/module.h>
	42	#include <linux/personality.h>
	43	#include <linux/ptrace.h>
	44	#include <linux/sched.h>
	45	#include <linux/stddef.h>
	46	#include <linux/unistd.h>
	47	#include <linux/kallsyms.h>
	48
	49	#include <asm/io.h>
	50	#include <asm/offsets.h>
	51	#include <asm/pdc.h>
	52	#include <asm/pdc_chassis.h>
	53	#include <asm/pgalloc.h>
	54	#include <asm/uaccess.h>
	55	#include <asm/unwind.h>
	56
	57	static int hlt_counter;
	58
	59	/*
	60	* Power off function, if any
	61	*/
	62	void (*pm_power_off)(void);
	63
	64	void disable_hlt(void)
65	{
66	hlt_counter++;
67	}
68
69	EXPORT_SYMBOL(disable_hlt);
70
71	void enable_hlt(void)
72	{
73	hlt_counter--;
74	}
75
76	EXPORT_SYMBOL(enable_hlt);
77
78	void default_idle(void)
79	{
80	barrier();
81	}
82
83	/*
84	* The idle thread. There's no useful work to be
85	* done, so just try to conserve power and have a
86	* low exit latency (ie sit in a loop waiting for
87	* somebody to say that they'd like to reschedule)
88	*/
89	void cpu_idle(void)
90	{
91	/* endless idle loop with no priority at all */
92	while (1) {
93	while (!need_resched())
94	barrier();
95	schedule();
96	check_pgt_cache();
97	}
98	}
99
100
101	#ifdef __LP64__
102	#define COMMAND_GLOBAL 0xfffffffffffe0030UL
103	#else
104	#define COMMAND_GLOBAL 0xfffe0030
105	#endif
106
107	#define CMD_RESET 5 /* reset any module */
108
109	/*
110	** The Wright Brothers and Gecko systems have a H/W problem
111	** (Lasi...'nuf said) may cause a broadcast reset to lockup
112	** the system. An HVERSION dependent PDC call was developed
113	** to perform a "safe", platform specific broadcast reset instead
114	** of kludging up all the code.
115	**
116	** Older machines which do not implement PDC_BROADCAST_RESET will
117	** return (with an error) and the regular broadcast reset can be
118	** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
119	** the PDC call will not return (the system will be reset).
120	*/
121	void machine_restart(char *cmd)
122	{
123	#ifdef FASTBOOT_SELFTEST_SUPPORT
124	/*
125	** If user has modified the Firmware Selftest Bitmap,
126	** run the tests specified in the bitmap after the
127	** system is rebooted w/PDC_DO_RESET.
128	**
129	** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
130	**
131	** Using "directed resets" at each processor with the MEM_TOC
132	** vector cleared will also avoid running destructive
133	** memory self tests. (Not implemented yet)
134	*/
135	if (ftc_bitmap) {
136	pdc_do_firm_test_reset(ftc_bitmap);
137	}
138	#endif
139	/* set up a new led state on systems shipped with a LED State panel */
140	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
141
142	/* "Normal" system reset */
143	pdc_do_reset();
144
145	/* Nope...box should reset with just CMD_RESET now */
146	gsc_writel(CMD_RESET, COMMAND_GLOBAL);
147
148	/* Wait for RESET to lay us to rest. */
149	while (1) ;
150
151	}
152
1da177e4 LT	153	void machine_halt(void)
	154	{
	155	/*
	156	** The LED/ChassisCodes are updated by the led_halt()
	157	** function, called by the reboot notifier chain.
	158	*/
	159	}
	160
1da177e4 LT	161
	162	/*
	163	* This routine is called from sys_reboot to actually turn off the
	164	* machine
	165	*/
	166	void machine_power_off(void)
	167	{
	168	/* If there is a registered power off handler, call it. */
	169	if(pm_power_off)
	170	pm_power_off();
	171
	172	/* Put the soft power button back under hardware control.
	173	* If the user had already pressed the power button, the
	174	* following call will immediately power off. */
	175	pdc_soft_power_button(0);
	176
	177	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	178
	179	/* It seems we have no way to power the system off via
	180	* software. The user has to press the button himself. */
	181
	182	printk(KERN_EMERG "System shut down completed.\n"
	183	KERN_EMERG "Please power this system off now.");
	184	}
	185
1da177e4 LT	186
	187	/*
	188	* Create a kernel thread
	189	*/
	190
	191	extern pid_t __kernel_thread(int (fn)(void ), void *arg, unsigned long flags);
	192	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	193	{
	194
	195	/*
	196	* FIXME: Once we are sure we don't need any debug here,
	197	* kernel_thread can become a #define.
	198	*/
	199
	200	return __kernel_thread(fn, arg, flags);
	201	}
	202	EXPORT_SYMBOL(kernel_thread);
	203
	204	/*
	205	* Free current thread data structures etc..
	206	*/
	207	void exit_thread(void)
	208	{
	209	}
	210
	211	void flush_thread(void)
	212	{
	213	/* Only needs to handle fpu stuff or perf monitors.
	214	** REVISIT: several arches implement a "lazy fpu state".
	215	*/
	216	set_fs(USER_DS);
	217	}
	218
	219	void release_thread(struct task_struct *dead_task)
	220	{
	221	}
	222
	223	/*
	224	* Fill in the FPU structure for a core dump.
	225	*/
	226
	227	int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
	228	{
	229	if (regs == NULL)
	230	return 0;
	231
	232	memcpy(r, regs->fr, sizeof *r);
	233	return 1;
	234	}
	235
	236	int dump_task_fpu (struct task_struct tsk, elf_fpregset_t r)
	237	{
	238	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	239	return 1;
	240	}
	241
	242	/* Note that "fork()" is implemented in terms of clone, with
	243	parameters (SIGCHLD, regs->gr[30], regs). */
	244	int
	245	sys_clone(unsigned long clone_flags, unsigned long usp,
	246	struct pt_regs *regs)
	247	{
	248	int __user user_tid = (int __user )regs->gr[26];
	249
250	/* usp must be word aligned. This also prevents users from
251	* passing in the value 1 (which is the signal for a special
252	* return for a kernel thread) */
253	usp = ALIGN(usp, 4);
254
255	/* A zero value for usp means use the current stack */
256	if(usp == 0)
257	usp = regs->gr[30];
258
259	return do_fork(clone_flags, usp, regs, 0, user_tid, NULL);
260	}
261
262	int
263	sys_vfork(struct pt_regs *regs)
264	{
265	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
266	}
267
268	int
269	copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
270	unsigned long unused, /* in ia64 this is "user_stack_size" */
271	struct task_struct * p, struct pt_regs * pregs)
272	{
273	struct pt_regs * cregs = &(p->thread.regs);
274	struct thread_info *ti = p->thread_info;
275
276	/* We have to use void * instead of a function pointer, because
277	* function pointers aren't a pointer to the function on 64-bit.
278	* Make them const so the compiler knows they live in .text */
279	extern void * const ret_from_kernel_thread;
280	extern void * const child_return;
281	#ifdef CONFIG_HPUX
282	extern void * const hpux_child_return;
283	#endif
284
285	cregs = pregs;
286
287	/* Set the return value for the child. Note that this is not
288	actually restored by the syscall exit path, but we put it
289	here for consistency in case of signals. */
290	cregs->gr[28] = 0; /* child */
291
292	/*
293	* We need to differentiate between a user fork and a
294	* kernel fork. We can't use user_mode, because the
295	* the syscall path doesn't save iaoq. Right now
296	* We rely on the fact that kernel_thread passes
297	* in zero for usp.
298	*/
299	if (usp == 1) {
300	/* kernel thread */
301	cregs->ksp = (((unsigned long)(ti)) + THREAD_SZ_ALGN);
302	/* Must exit via ret_from_kernel_thread in order
303	* to call schedule_tail()
304	*/
305	cregs->kpc = (unsigned long) &ret_from_kernel_thread;
306	/*
307	* Copy function and argument to be called from
308	* ret_from_kernel_thread.
309	*/
310	#ifdef __LP64__
311	cregs->gr[27] = pregs->gr[27];
312	#endif
313	cregs->gr[26] = pregs->gr[26];
314	cregs->gr[25] = pregs->gr[25];
315	} else {
316	/* user thread */
317	/*
318	* Note that the fork wrappers are responsible
319	* for setting gr[21].
320	*/
321
322	/* Use same stack depth as parent */
323	cregs->ksp = ((unsigned long)(ti))
324	+ (pregs->gr[21] & (THREAD_SIZE - 1));
325	cregs->gr[30] = usp;
326	if (p->personality == PER_HPUX) {
327	#ifdef CONFIG_HPUX
328	cregs->kpc = (unsigned long) &hpux_child_return;
329	#else
330	BUG();
331	#endif
332	} else {
333	cregs->kpc = (unsigned long) &child_return;
334	}
335	}
336
337	return 0;
338	}
339
340	unsigned long thread_saved_pc(struct task_struct *t)
341	{
342	return t->thread.regs.kpc;
343	}
344
345	/*
346	* sys_execve() executes a new program.
347	*/
348
349	asmlinkage int sys_execve(struct pt_regs *regs)
350	{
351	int error;
352	char *filename;
353
354	filename = getname((const char __user *) regs->gr[26]);
355	error = PTR_ERR(filename);
356	if (IS_ERR(filename))
357	goto out;
358	error = do_execve(filename, (char __user **) regs->gr[25],
359	(char __user **) regs->gr[24], regs);
360	if (error == 0) {
361	task_lock(current);
362	current->ptrace &= ~PT_DTRACE;
363	task_unlock(current);
364	}
365	putname(filename);
366	out:
367
368	return error;
369	}
370
371	unsigned long
372	get_wchan(struct task_struct *p)
373	{
374	struct unwind_frame_info info;
375	unsigned long ip;
376	int count = 0;
377	/*
378	* These bracket the sleeping functions..
379	*/
380
381	unwind_frame_init_from_blocked_task(&info, p);
382	do {
383	if (unwind_once(&info) < 0)
384	return 0;
385	ip = info.ip;
386	if (!in_sched_functions(ip))
387	return ip;
388	} while (count++ < 16);
389	return 0;
390	}