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) 2001-2002 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>
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>
50 #include <asm/asm-offsets.h>
52 #include <asm/pdc_chassis.h>
53 #include <asm/pgalloc.h>
54 #include <asm/uaccess.h>
55 #include <asm/unwind.h>
57 static int hlt_counter __read_mostly;
60 * Power off function, if any
62 void (*pm_power_off)(void);
64 void disable_hlt(void)
69 EXPORT_SYMBOL(disable_hlt);
76 EXPORT_SYMBOL(enable_hlt);
78 void default_idle(void)
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)
91 set_thread_flag(TIF_POLLING_NRFLAG);
93 /* endless idle loop with no priority at all */
95 while (!need_resched())
97 preempt_enable_no_resched();
105 #define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
106 #define CMD_RESET 5 /* reset any module */
109 ** The Wright Brothers and Gecko systems have a H/W problem
110 ** (Lasi...'nuf said) may cause a broadcast reset to lockup
111 ** the system. An HVERSION dependent PDC call was developed
112 ** to perform a "safe", platform specific broadcast reset instead
113 ** of kludging up all the code.
115 ** Older machines which do not implement PDC_BROADCAST_RESET will
116 ** return (with an error) and the regular broadcast reset can be
117 ** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
118 ** the PDC call will not return (the system will be reset).
120 void machine_restart(char *cmd)
122 #ifdef FASTBOOT_SELFTEST_SUPPORT
124 ** If user has modified the Firmware Selftest Bitmap,
125 ** run the tests specified in the bitmap after the
126 ** system is rebooted w/PDC_DO_RESET.
128 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
130 ** Using "directed resets" at each processor with the MEM_TOC
131 ** vector cleared will also avoid running destructive
132 ** memory self tests. (Not implemented yet)
135 pdc_do_firm_test_reset(ftc_bitmap);
138 /* set up a new led state on systems shipped with a LED State panel */
139 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
141 /* "Normal" system reset */
144 /* Nope...box should reset with just CMD_RESET now */
145 gsc_writel(CMD_RESET, COMMAND_GLOBAL);
147 /* Wait for RESET to lay us to rest. */
152 void machine_halt(void)
155 ** The LED/ChassisCodes are updated by the led_halt()
156 ** function, called by the reboot notifier chain.
162 * This routine is called from sys_reboot to actually turn off the
165 void machine_power_off(void)
167 /* If there is a registered power off handler, call it. */
171 /* Put the soft power button back under hardware control.
172 * If the user had already pressed the power button, the
173 * following call will immediately power off. */
174 pdc_soft_power_button(0);
176 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
178 /* It seems we have no way to power the system off via
179 * software. The user has to press the button himself. */
181 printk(KERN_EMERG "System shut down completed.\n"
182 KERN_EMERG "Please power this system off now.");
187 * Create a kernel thread
190 extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
191 pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
195 * FIXME: Once we are sure we don't need any debug here,
196 * kernel_thread can become a #define.
199 return __kernel_thread(fn, arg, flags);
201 EXPORT_SYMBOL(kernel_thread);
204 * Free current thread data structures etc..
206 void exit_thread(void)
210 void flush_thread(void)
212 /* Only needs to handle fpu stuff or perf monitors.
213 ** REVISIT: several arches implement a "lazy fpu state".
218 void release_thread(struct task_struct *dead_task)
223 * Fill in the FPU structure for a core dump.
226 int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
231 memcpy(r, regs->fr, sizeof *r);
235 int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
237 memcpy(r, tsk->thread.regs.fr, sizeof(*r));
241 /* Note that "fork()" is implemented in terms of clone, with
242 parameters (SIGCHLD, regs->gr[30], regs). */
244 sys_clone(unsigned long clone_flags, unsigned long usp,
245 struct pt_regs *regs)
247 /* Arugments from userspace are:
251 r23 = Is the TLS storage descriptor
254 However, these last 3 args are only examined
255 if the proper flags are set. */
256 int __user *child_tidptr;
257 int __user *parent_tidptr;
259 /* usp must be word aligned. This also prevents users from
260 * passing in the value 1 (which is the signal for a special
261 * return for a kernel thread) */
264 /* A zero value for usp means use the current stack */
268 if (clone_flags & CLONE_PARENT_SETTID)
269 parent_tidptr = (int __user *)regs->gr[24];
271 parent_tidptr = NULL;
273 if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID))
274 child_tidptr = (int __user *)regs->gr[22];
278 return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
282 sys_vfork(struct pt_regs *regs)
284 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
288 copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
289 unsigned long unused, /* in ia64 this is "user_stack_size" */
290 struct task_struct * p, struct pt_regs * pregs)
292 struct pt_regs * cregs = &(p->thread.regs);
293 void *stack = task_stack_page(p);
295 /* We have to use void * instead of a function pointer, because
296 * function pointers aren't a pointer to the function on 64-bit.
297 * Make them const so the compiler knows they live in .text */
298 extern void * const ret_from_kernel_thread;
299 extern void * const child_return;
301 extern void * const hpux_child_return;
306 /* Set the return value for the child. Note that this is not
307 actually restored by the syscall exit path, but we put it
308 here for consistency in case of signals. */
309 cregs->gr[28] = 0; /* child */
312 * We need to differentiate between a user fork and a
313 * kernel fork. We can't use user_mode, because the
314 * the syscall path doesn't save iaoq. Right now
315 * We rely on the fact that kernel_thread passes
320 cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
321 /* Must exit via ret_from_kernel_thread in order
322 * to call schedule_tail()
324 cregs->kpc = (unsigned long) &ret_from_kernel_thread;
326 * Copy function and argument to be called from
327 * ret_from_kernel_thread.
330 cregs->gr[27] = pregs->gr[27];
332 cregs->gr[26] = pregs->gr[26];
333 cregs->gr[25] = pregs->gr[25];
337 * Note that the fork wrappers are responsible
338 * for setting gr[21].
341 /* Use same stack depth as parent */
342 cregs->ksp = (unsigned long)stack
343 + (pregs->gr[21] & (THREAD_SIZE - 1));
345 if (p->personality == PER_HPUX) {
347 cregs->kpc = (unsigned long) &hpux_child_return;
352 cregs->kpc = (unsigned long) &child_return;
354 /* Setup thread TLS area from the 4th parameter in clone */
355 if (clone_flags & CLONE_SETTLS)
356 cregs->cr27 = pregs->gr[23];
363 unsigned long thread_saved_pc(struct task_struct *t)
365 return t->thread.regs.kpc;
369 * sys_execve() executes a new program.
372 asmlinkage int sys_execve(struct pt_regs *regs)
377 filename = getname((const char __user *) regs->gr[26]);
378 error = PTR_ERR(filename);
379 if (IS_ERR(filename))
381 error = do_execve(filename, (char __user **) regs->gr[25],
382 (char __user **) regs->gr[24], regs);
385 current->ptrace &= ~PT_DTRACE;
386 task_unlock(current);
395 get_wchan(struct task_struct *p)
397 struct unwind_frame_info info;
401 * These bracket the sleeping functions..
404 unwind_frame_init_from_blocked_task(&info, p);
406 if (unwind_once(&info) < 0)
409 if (!in_sched_functions(ip))
411 } while (count++ < 16);