2 * PARISC Architecture-dependent parts of process handling
3 * based on the work for i386
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-linux.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) 2001-2007 Helge Deller <deller at parisc-linux.org>
17 * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
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.
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.
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
37 #include <linux/elf.h>
38 #include <linux/errno.h>
39 #include <linux/kernel.h>
42 #include <linux/module.h>
43 #include <linux/personality.h>
44 #include <linux/ptrace.h>
45 #include <linux/sched.h>
46 #include <linux/slab.h>
47 #include <linux/stddef.h>
48 #include <linux/unistd.h>
49 #include <linux/kallsyms.h>
50 #include <linux/uaccess.h>
53 #include <asm/asm-offsets.h>
55 #include <asm/pdc_chassis.h>
56 #include <asm/pgalloc.h>
57 #include <asm/unwind.h>
58 #include <asm/sections.h>
61 * The idle thread. There's no useful work to be
62 * done, so just try to conserve power and have a
63 * low exit latency (ie sit in a loop waiting for
64 * somebody to say that they'd like to reschedule)
68 set_thread_flag(TIF_POLLING_NRFLAG
);
70 /* endless idle loop with no priority at all */
72 while (!need_resched())
74 schedule_preempt_disabled();
80 #define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
81 #define CMD_RESET 5 /* reset any module */
84 ** The Wright Brothers and Gecko systems have a H/W problem
85 ** (Lasi...'nuf said) may cause a broadcast reset to lockup
86 ** the system. An HVERSION dependent PDC call was developed
87 ** to perform a "safe", platform specific broadcast reset instead
88 ** of kludging up all the code.
90 ** Older machines which do not implement PDC_BROADCAST_RESET will
91 ** return (with an error) and the regular broadcast reset can be
92 ** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
93 ** the PDC call will not return (the system will be reset).
95 void machine_restart(char *cmd
)
97 #ifdef FASTBOOT_SELFTEST_SUPPORT
99 ** If user has modified the Firmware Selftest Bitmap,
100 ** run the tests specified in the bitmap after the
101 ** system is rebooted w/PDC_DO_RESET.
103 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
105 ** Using "directed resets" at each processor with the MEM_TOC
106 ** vector cleared will also avoid running destructive
107 ** memory self tests. (Not implemented yet)
110 pdc_do_firm_test_reset(ftc_bitmap
);
113 /* set up a new led state on systems shipped with a LED State panel */
114 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN
);
116 /* "Normal" system reset */
119 /* Nope...box should reset with just CMD_RESET now */
120 gsc_writel(CMD_RESET
, COMMAND_GLOBAL
);
122 /* Wait for RESET to lay us to rest. */
127 void machine_halt(void)
130 ** The LED/ChassisCodes are updated by the led_halt()
131 ** function, called by the reboot notifier chain.
135 void (*chassis_power_off
)(void);
138 * This routine is called from sys_reboot to actually turn off the
141 void machine_power_off(void)
143 /* If there is a registered power off handler, call it. */
144 if (chassis_power_off
)
147 /* Put the soft power button back under hardware control.
148 * If the user had already pressed the power button, the
149 * following call will immediately power off. */
150 pdc_soft_power_button(0);
152 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN
);
154 /* It seems we have no way to power the system off via
155 * software. The user has to press the button himself. */
157 printk(KERN_EMERG
"System shut down completed.\n"
158 "Please power this system off now.");
161 void (*pm_power_off
)(void) = machine_power_off
;
162 EXPORT_SYMBOL(pm_power_off
);
165 * Create a kernel thread
168 extern pid_t
__kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
);
169 pid_t
kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
)
173 * FIXME: Once we are sure we don't need any debug here,
174 * kernel_thread can become a #define.
177 return __kernel_thread(fn
, arg
, flags
);
179 EXPORT_SYMBOL(kernel_thread
);
182 * Free current thread data structures etc..
184 void exit_thread(void)
188 void flush_thread(void)
190 /* Only needs to handle fpu stuff or perf monitors.
191 ** REVISIT: several arches implement a "lazy fpu state".
195 void release_thread(struct task_struct
*dead_task
)
200 * Fill in the FPU structure for a core dump.
203 int dump_fpu (struct pt_regs
* regs
, elf_fpregset_t
*r
)
208 memcpy(r
, regs
->fr
, sizeof *r
);
212 int dump_task_fpu (struct task_struct
*tsk
, elf_fpregset_t
*r
)
214 memcpy(r
, tsk
->thread
.regs
.fr
, sizeof(*r
));
218 /* Note that "fork()" is implemented in terms of clone, with
219 parameters (SIGCHLD, regs->gr[30], regs). */
221 sys_clone(unsigned long clone_flags
, unsigned long usp
,
222 struct pt_regs
*regs
)
224 /* Arugments from userspace are:
228 r23 = Is the TLS storage descriptor
231 However, these last 3 args are only examined
232 if the proper flags are set. */
233 int __user
*parent_tidptr
= (int __user
*)regs
->gr
[24];
234 int __user
*child_tidptr
= (int __user
*)regs
->gr
[22];
236 /* usp must be word aligned. This also prevents users from
237 * passing in the value 1 (which is the signal for a special
238 * return for a kernel thread) */
241 /* A zero value for usp means use the current stack */
245 return do_fork(clone_flags
, usp
, regs
, 0, parent_tidptr
, child_tidptr
);
249 sys_vfork(struct pt_regs
*regs
)
251 return do_fork(CLONE_VFORK
| CLONE_VM
| SIGCHLD
, regs
->gr
[30], regs
, 0, NULL
, NULL
);
255 copy_thread(unsigned long clone_flags
, unsigned long usp
,
256 unsigned long unused
, /* in ia64 this is "user_stack_size" */
257 struct task_struct
* p
, struct pt_regs
* pregs
)
259 struct pt_regs
* cregs
= &(p
->thread
.regs
);
260 void *stack
= task_stack_page(p
);
262 /* We have to use void * instead of a function pointer, because
263 * function pointers aren't a pointer to the function on 64-bit.
264 * Make them const so the compiler knows they live in .text */
265 extern void * const ret_from_kernel_thread
;
266 extern void * const child_return
;
268 extern void * const hpux_child_return
;
273 /* Set the return value for the child. Note that this is not
274 actually restored by the syscall exit path, but we put it
275 here for consistency in case of signals. */
276 cregs
->gr
[28] = 0; /* child */
279 * We need to differentiate between a user fork and a
280 * kernel fork. We can't use user_mode, because the
281 * the syscall path doesn't save iaoq. Right now
282 * We rely on the fact that kernel_thread passes
287 cregs
->ksp
= (unsigned long)stack
+ THREAD_SZ_ALGN
;
288 /* Must exit via ret_from_kernel_thread in order
289 * to call schedule_tail()
291 cregs
->kpc
= (unsigned long) &ret_from_kernel_thread
;
293 * Copy function and argument to be called from
294 * ret_from_kernel_thread.
297 cregs
->gr
[27] = pregs
->gr
[27];
299 cregs
->gr
[26] = pregs
->gr
[26];
300 cregs
->gr
[25] = pregs
->gr
[25];
304 * Note that the fork wrappers are responsible
305 * for setting gr[21].
308 /* Use same stack depth as parent */
309 cregs
->ksp
= (unsigned long)stack
310 + (pregs
->gr
[21] & (THREAD_SIZE
- 1));
312 if (p
->personality
== PER_HPUX
) {
314 cregs
->kpc
= (unsigned long) &hpux_child_return
;
319 cregs
->kpc
= (unsigned long) &child_return
;
321 /* Setup thread TLS area from the 4th parameter in clone */
322 if (clone_flags
& CLONE_SETTLS
)
323 cregs
->cr27
= pregs
->gr
[23];
330 unsigned long thread_saved_pc(struct task_struct
*t
)
332 return t
->thread
.regs
.kpc
;
336 * sys_execve() executes a new program.
339 asmlinkage
int sys_execve(struct pt_regs
*regs
)
344 filename
= getname((const char __user
*) regs
->gr
[26]);
345 error
= PTR_ERR(filename
);
346 if (IS_ERR(filename
))
348 error
= do_execve(filename
,
349 (const char __user
*const __user
*) regs
->gr
[25],
350 (const char __user
*const __user
*) regs
->gr
[24],
358 extern int __execve(const char *filename
,
359 const char *const argv
[],
360 const char *const envp
[], struct task_struct
*task
);
361 int kernel_execve(const char *filename
,
362 const char *const argv
[],
363 const char *const envp
[])
365 return __execve(filename
, argv
, envp
, current
);
369 get_wchan(struct task_struct
*p
)
371 struct unwind_frame_info info
;
375 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
379 * These bracket the sleeping functions..
382 unwind_frame_init_from_blocked_task(&info
, p
);
384 if (unwind_once(&info
) < 0)
387 if (!in_sched_functions(ip
))
389 } while (count
++ < 16);
394 void *dereference_function_descriptor(void *ptr
)
396 Elf64_Fdesc
*desc
= ptr
;
399 if (!probe_kernel_address(&desc
->addr
, p
))