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/stddef.h>
47 #include <linux/unistd.h>
48 #include <linux/kallsyms.h>
51 #include <asm/asm-offsets.h>
53 #include <asm/pdc_chassis.h>
54 #include <asm/pgalloc.h>
55 #include <asm/uaccess.h>
56 #include <asm/unwind.h>
59 * The idle thread. There's no useful work to be
60 * done, so just try to conserve power and have a
61 * low exit latency (ie sit in a loop waiting for
62 * somebody to say that they'd like to reschedule)
66 set_thread_flag(TIF_POLLING_NRFLAG);
68 /* endless idle loop with no priority at all */
70 while (!need_resched())
72 preempt_enable_no_resched();
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 KERN_EMERG "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".
196 void release_thread(struct task_struct *dead_task)
201 * Fill in the FPU structure for a core dump.
204 int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
209 memcpy(r, regs->fr, sizeof *r);
213 int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
215 memcpy(r, tsk->thread.regs.fr, sizeof(*r));
219 /* Note that "fork()" is implemented in terms of clone, with
220 parameters (SIGCHLD, regs->gr[30], regs). */
222 sys_clone(unsigned long clone_flags, unsigned long usp,
223 struct pt_regs *regs)
225 /* Arugments from userspace are:
229 r23 = Is the TLS storage descriptor
232 However, these last 3 args are only examined
233 if the proper flags are set. */
234 int __user *parent_tidptr = (int __user *)regs->gr[24];
235 int __user *child_tidptr = (int __user *)regs->gr[22];
237 /* usp must be word aligned. This also prevents users from
238 * passing in the value 1 (which is the signal for a special
239 * return for a kernel thread) */
242 /* A zero value for usp means use the current stack */
246 return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
250 sys_vfork(struct pt_regs *regs)
252 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
256 copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
257 unsigned long unused, /* in ia64 this is "user_stack_size" */
258 struct task_struct * p, struct pt_regs * pregs)
260 struct pt_regs * cregs = &(p->thread.regs);
261 void *stack = task_stack_page(p);
263 /* We have to use void * instead of a function pointer, because
264 * function pointers aren't a pointer to the function on 64-bit.
265 * Make them const so the compiler knows they live in .text */
266 extern void * const ret_from_kernel_thread;
267 extern void * const child_return;
269 extern void * const hpux_child_return;
274 /* Set the return value for the child. Note that this is not
275 actually restored by the syscall exit path, but we put it
276 here for consistency in case of signals. */
277 cregs->gr[28] = 0; /* child */
280 * We need to differentiate between a user fork and a
281 * kernel fork. We can't use user_mode, because the
282 * the syscall path doesn't save iaoq. Right now
283 * We rely on the fact that kernel_thread passes
288 cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
289 /* Must exit via ret_from_kernel_thread in order
290 * to call schedule_tail()
292 cregs->kpc = (unsigned long) &ret_from_kernel_thread;
294 * Copy function and argument to be called from
295 * ret_from_kernel_thread.
298 cregs->gr[27] = pregs->gr[27];
300 cregs->gr[26] = pregs->gr[26];
301 cregs->gr[25] = pregs->gr[25];
305 * Note that the fork wrappers are responsible
306 * for setting gr[21].
309 /* Use same stack depth as parent */
310 cregs->ksp = (unsigned long)stack
311 + (pregs->gr[21] & (THREAD_SIZE - 1));
313 if (p->personality == PER_HPUX) {
315 cregs->kpc = (unsigned long) &hpux_child_return;
320 cregs->kpc = (unsigned long) &child_return;
322 /* Setup thread TLS area from the 4th parameter in clone */
323 if (clone_flags & CLONE_SETTLS)
324 cregs->cr27 = pregs->gr[23];
331 unsigned long thread_saved_pc(struct task_struct *t)
333 return t->thread.regs.kpc;
337 * sys_execve() executes a new program.
340 asmlinkage int sys_execve(struct pt_regs *regs)
345 filename = getname((const char __user *) regs->gr[26]);
346 error = PTR_ERR(filename);
347 if (IS_ERR(filename))
349 error = do_execve(filename, (char __user * __user *) regs->gr[25],
350 (char __user * __user *) regs->gr[24], regs);
353 current->ptrace &= ~PT_DTRACE;
354 task_unlock(current);
362 extern int __execve(const char *filename, char *const argv[],
363 char *const envp[], struct task_struct *task);
364 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
366 return __execve(filename, argv, envp, current);
370 get_wchan(struct task_struct *p)
372 struct unwind_frame_info info;
376 if (!p || p == current || p->state == TASK_RUNNING)
380 * These bracket the sleeping functions..
383 unwind_frame_init_from_blocked_task(&info, p);
385 if (unwind_once(&info) < 0)
388 if (!in_sched_functions(ip))
390 } while (count++ < 16);