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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PARISC Architecture-dependent parts of process handling
4 * based on the work for i386
5 *
6 * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
7 * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
8 * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
9 * Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
10 * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
11 * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
12 * Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
13 * Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
14 * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
15 * Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
16 * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
17 * Copyright (C) 2001-2014 Helge Deller <deller@gmx.de>
18 * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
19 */
20
21#include <stdarg.h>
22
23#include <linux/elf.h>
24#include <linux/errno.h>
25#include <linux/kernel.h>
26#include <linux/mm.h>
27#include <linux/fs.h>
28#include <linux/cpu.h>
29#include <linux/module.h>
30#include <linux/personality.h>
31#include <linux/ptrace.h>
32#include <linux/sched.h>
33#include <linux/sched/debug.h>
34#include <linux/sched/task.h>
35#include <linux/sched/task_stack.h>
36#include <linux/slab.h>
37#include <linux/stddef.h>
38#include <linux/unistd.h>
39#include <linux/kallsyms.h>
40#include <linux/uaccess.h>
41#include <linux/rcupdate.h>
42#include <linux/random.h>
43#include <linux/nmi.h>
44
45#include <asm/io.h>
46#include <asm/asm-offsets.h>
47#include <asm/assembly.h>
48#include <asm/pdc.h>
49#include <asm/pdc_chassis.h>
50#include <asm/pgalloc.h>
51#include <asm/unwind.h>
52#include <asm/sections.h>
53
54#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
55#define CMD_RESET 5 /* reset any module */
56
57/*
58** The Wright Brothers and Gecko systems have a H/W problem
59** (Lasi...'nuf said) may cause a broadcast reset to lockup
60** the system. An HVERSION dependent PDC call was developed
61** to perform a "safe", platform specific broadcast reset instead
62** of kludging up all the code.
63**
64** Older machines which do not implement PDC_BROADCAST_RESET will
65** return (with an error) and the regular broadcast reset can be
66** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
67** the PDC call will not return (the system will be reset).
68*/
69void machine_restart(char *cmd)
70{
71#ifdef FASTBOOT_SELFTEST_SUPPORT
72 /*
73 ** If user has modified the Firmware Selftest Bitmap,
74 ** run the tests specified in the bitmap after the
75 ** system is rebooted w/PDC_DO_RESET.
76 **
77 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
78 **
79 ** Using "directed resets" at each processor with the MEM_TOC
80 ** vector cleared will also avoid running destructive
81 ** memory self tests. (Not implemented yet)
82 */
83 if (ftc_bitmap) {
84 pdc_do_firm_test_reset(ftc_bitmap);
85 }
86#endif
87 /* set up a new led state on systems shipped with a LED State panel */
88 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
89
90 /* "Normal" system reset */
91 pdc_do_reset();
92
93 /* Nope...box should reset with just CMD_RESET now */
94 gsc_writel(CMD_RESET, COMMAND_GLOBAL);
95
96 /* Wait for RESET to lay us to rest. */
97 while (1) ;
98
99}
100
101void (*chassis_power_off)(void);
102
103/*
104 * This routine is called from sys_reboot to actually turn off the
105 * machine
106 */
107void machine_power_off(void)
108{
109 /* If there is a registered power off handler, call it. */
110 if (chassis_power_off)
111 chassis_power_off();
112
113 /* Put the soft power button back under hardware control.
114 * If the user had already pressed the power button, the
115 * following call will immediately power off. */
116 pdc_soft_power_button(0);
117
118 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
119
120 /* ipmi_poweroff may have been installed. */
121 if (pm_power_off)
122 pm_power_off();
123
124 /* It seems we have no way to power the system off via
125 * software. The user has to press the button himself. */
126
127 printk(KERN_EMERG "System shut down completed.\n"
128 "Please power this system off now.");
129
130 /* prevent soft lockup/stalled CPU messages for endless loop. */
131 rcu_sysrq_start();
132 lockup_detector_soft_poweroff();
133 for (;;);
134}
135
136void (*pm_power_off)(void);
137EXPORT_SYMBOL(pm_power_off);
138
139void machine_halt(void)
140{
141 machine_power_off();
142}
143
144void flush_thread(void)
145{
146 /* Only needs to handle fpu stuff or perf monitors.
147 ** REVISIT: several arches implement a "lazy fpu state".
148 */
149}
150
151void release_thread(struct task_struct *dead_task)
152{
153}
154
155/*
156 * Fill in the FPU structure for a core dump.
157 */
158
159int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
160{
161 if (regs == NULL)
162 return 0;
163
164 memcpy(r, regs->fr, sizeof *r);
165 return 1;
166}
167
168int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
169{
170 memcpy(r, tsk->thread.regs.fr, sizeof(*r));
171 return 1;
172}
173
174/*
175 * Idle thread support
176 *
177 * Detect when running on QEMU with SeaBIOS PDC Firmware and let
178 * QEMU idle the host too.
179 */
180
181int running_on_qemu __ro_after_init;
182EXPORT_SYMBOL(running_on_qemu);
183
184void __cpuidle arch_cpu_idle_dead(void)
185{
186 /* nop on real hardware, qemu will offline CPU. */
187 asm volatile("or %%r31,%%r31,%%r31\n":::);
188}
189
190void __cpuidle arch_cpu_idle(void)
191{
192 local_irq_enable();
193
194 /* nop on real hardware, qemu will idle sleep. */
195 asm volatile("or %%r10,%%r10,%%r10\n":::);
196}
197
198static int __init parisc_idle_init(void)
199{
200 if (!running_on_qemu)
201 cpu_idle_poll_ctrl(1);
202
203 return 0;
204}
205arch_initcall(parisc_idle_init);
206
207/*
208 * Copy architecture-specific thread state
209 */
210int
211copy_thread(unsigned long clone_flags, unsigned long usp,
212 unsigned long kthread_arg, struct task_struct *p)
213{
214 struct pt_regs *cregs = &(p->thread.regs);
215 void *stack = task_stack_page(p);
216
217 /* We have to use void * instead of a function pointer, because
218 * function pointers aren't a pointer to the function on 64-bit.
219 * Make them const so the compiler knows they live in .text */
220 extern void * const ret_from_kernel_thread;
221 extern void * const child_return;
222
223 if (unlikely(p->flags & PF_KTHREAD)) {
224 /* kernel thread */
225 memset(cregs, 0, sizeof(struct pt_regs));
226 if (!usp) /* idle thread */
227 return 0;
228 /* Must exit via ret_from_kernel_thread in order
229 * to call schedule_tail()
230 */
231 cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
232 cregs->kpc = (unsigned long) &ret_from_kernel_thread;
233 /*
234 * Copy function and argument to be called from
235 * ret_from_kernel_thread.
236 */
237#ifdef CONFIG_64BIT
238 cregs->gr[27] = ((unsigned long *)usp)[3];
239 cregs->gr[26] = ((unsigned long *)usp)[2];
240#else
241 cregs->gr[26] = usp;
242#endif
243 cregs->gr[25] = kthread_arg;
244 } else {
245 /* user thread */
246 /* usp must be word aligned. This also prevents users from
247 * passing in the value 1 (which is the signal for a special
248 * return for a kernel thread) */
249 if (usp) {
250 usp = ALIGN(usp, 4);
251 if (likely(usp))
252 cregs->gr[30] = usp;
253 }
254 cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
255 cregs->kpc = (unsigned long) &child_return;
256
257 /* Setup thread TLS area from the 4th parameter in clone */
258 if (clone_flags & CLONE_SETTLS)
259 cregs->cr27 = cregs->gr[23];
260 }
261
262 return 0;
263}
264
265unsigned long
266get_wchan(struct task_struct *p)
267{
268 struct unwind_frame_info info;
269 unsigned long ip;
270 int count = 0;
271
272 if (!p || p == current || p->state == TASK_RUNNING)
273 return 0;
274
275 /*
276 * These bracket the sleeping functions..
277 */
278
279 unwind_frame_init_from_blocked_task(&info, p);
280 do {
281 if (unwind_once(&info) < 0)
282 return 0;
283 ip = info.ip;
284 if (!in_sched_functions(ip))
285 return ip;
286 } while (count++ < MAX_UNWIND_ENTRIES);
287 return 0;
288}
289
290#ifdef CONFIG_64BIT
291void *dereference_function_descriptor(void *ptr)
292{
293 Elf64_Fdesc *desc = ptr;
294 void *p;
295
296 if (!probe_kernel_address(&desc->addr, p))
297 ptr = p;
298 return ptr;
299}
300
301void *dereference_kernel_function_descriptor(void *ptr)
302{
303 if (ptr < (void *)__start_opd ||
304 ptr >= (void *)__end_opd)
305 return ptr;
306
307 return dereference_function_descriptor(ptr);
308}
309#endif
310
311static inline unsigned long brk_rnd(void)
312{
313 return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT;
314}
315
316unsigned long arch_randomize_brk(struct mm_struct *mm)
317{
318 unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
319
320 if (ret < mm->brk)
321 return mm->brk;
322 return ret;
323}
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-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>
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/fs.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>
51
52#include <asm/io.h>
53#include <asm/asm-offsets.h>
54#include <asm/pdc.h>
55#include <asm/pdc_chassis.h>
56#include <asm/pgalloc.h>
57#include <asm/unwind.h>
58#include <asm/sections.h>
59
60/*
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)
65 */
66void cpu_idle(void)
67{
68 set_thread_flag(TIF_POLLING_NRFLAG);
69
70 /* endless idle loop with no priority at all */
71 while (1) {
72 while (!need_resched())
73 barrier();
74 preempt_enable_no_resched();
75 schedule();
76 preempt_disable();
77 check_pgt_cache();
78 }
79}
80
81
82#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
83#define CMD_RESET 5 /* reset any module */
84
85/*
86** The Wright Brothers and Gecko systems have a H/W problem
87** (Lasi...'nuf said) may cause a broadcast reset to lockup
88** the system. An HVERSION dependent PDC call was developed
89** to perform a "safe", platform specific broadcast reset instead
90** of kludging up all the code.
91**
92** Older machines which do not implement PDC_BROADCAST_RESET will
93** return (with an error) and the regular broadcast reset can be
94** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
95** the PDC call will not return (the system will be reset).
96*/
97void machine_restart(char *cmd)
98{
99#ifdef FASTBOOT_SELFTEST_SUPPORT
100 /*
101 ** If user has modified the Firmware Selftest Bitmap,
102 ** run the tests specified in the bitmap after the
103 ** system is rebooted w/PDC_DO_RESET.
104 **
105 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
106 **
107 ** Using "directed resets" at each processor with the MEM_TOC
108 ** vector cleared will also avoid running destructive
109 ** memory self tests. (Not implemented yet)
110 */
111 if (ftc_bitmap) {
112 pdc_do_firm_test_reset(ftc_bitmap);
113 }
114#endif
115 /* set up a new led state on systems shipped with a LED State panel */
116 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
117
118 /* "Normal" system reset */
119 pdc_do_reset();
120
121 /* Nope...box should reset with just CMD_RESET now */
122 gsc_writel(CMD_RESET, COMMAND_GLOBAL);
123
124 /* Wait for RESET to lay us to rest. */
125 while (1) ;
126
127}
128
129void machine_halt(void)
130{
131 /*
132 ** The LED/ChassisCodes are updated by the led_halt()
133 ** function, called by the reboot notifier chain.
134 */
135}
136
137void (*chassis_power_off)(void);
138
139/*
140 * This routine is called from sys_reboot to actually turn off the
141 * machine
142 */
143void machine_power_off(void)
144{
145 /* If there is a registered power off handler, call it. */
146 if (chassis_power_off)
147 chassis_power_off();
148
149 /* Put the soft power button back under hardware control.
150 * If the user had already pressed the power button, the
151 * following call will immediately power off. */
152 pdc_soft_power_button(0);
153
154 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
155
156 /* It seems we have no way to power the system off via
157 * software. The user has to press the button himself. */
158
159 printk(KERN_EMERG "System shut down completed.\n"
160 "Please power this system off now.");
161}
162
163void (*pm_power_off)(void) = machine_power_off;
164EXPORT_SYMBOL(pm_power_off);
165
166/*
167 * Create a kernel thread
168 */
169
170extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
171pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
172{
173
174 /*
175 * FIXME: Once we are sure we don't need any debug here,
176 * kernel_thread can become a #define.
177 */
178
179 return __kernel_thread(fn, arg, flags);
180}
181EXPORT_SYMBOL(kernel_thread);
182
183/*
184 * Free current thread data structures etc..
185 */
186void exit_thread(void)
187{
188}
189
190void flush_thread(void)
191{
192 /* Only needs to handle fpu stuff or perf monitors.
193 ** REVISIT: several arches implement a "lazy fpu state".
194 */
195 set_fs(USER_DS);
196}
197
198void release_thread(struct task_struct *dead_task)
199{
200}
201
202/*
203 * Fill in the FPU structure for a core dump.
204 */
205
206int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
207{
208 if (regs == NULL)
209 return 0;
210
211 memcpy(r, regs->fr, sizeof *r);
212 return 1;
213}
214
215int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
216{
217 memcpy(r, tsk->thread.regs.fr, sizeof(*r));
218 return 1;
219}
220
221/* Note that "fork()" is implemented in terms of clone, with
222 parameters (SIGCHLD, regs->gr[30], regs). */
223int
224sys_clone(unsigned long clone_flags, unsigned long usp,
225 struct pt_regs *regs)
226{
227 /* Arugments from userspace are:
228 r26 = Clone flags.
229 r25 = Child stack.
230 r24 = parent_tidptr.
231 r23 = Is the TLS storage descriptor
232 r22 = child_tidptr
233
234 However, these last 3 args are only examined
235 if the proper flags are set. */
236 int __user *parent_tidptr = (int __user *)regs->gr[24];
237 int __user *child_tidptr = (int __user *)regs->gr[22];
238
239 /* usp must be word aligned. This also prevents users from
240 * passing in the value 1 (which is the signal for a special
241 * return for a kernel thread) */
242 usp = ALIGN(usp, 4);
243
244 /* A zero value for usp means use the current stack */
245 if (usp == 0)
246 usp = regs->gr[30];
247
248 return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
249}
250
251int
252sys_vfork(struct pt_regs *regs)
253{
254 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
255}
256
257int
258copy_thread(unsigned long clone_flags, unsigned long usp,
259 unsigned long unused, /* in ia64 this is "user_stack_size" */
260 struct task_struct * p, struct pt_regs * pregs)
261{
262 struct pt_regs * cregs = &(p->thread.regs);
263 void *stack = task_stack_page(p);
264
265 /* We have to use void * instead of a function pointer, because
266 * function pointers aren't a pointer to the function on 64-bit.
267 * Make them const so the compiler knows they live in .text */
268 extern void * const ret_from_kernel_thread;
269 extern void * const child_return;
270#ifdef CONFIG_HPUX
271 extern void * const hpux_child_return;
272#endif
273
274 *cregs = *pregs;
275
276 /* Set the return value for the child. Note that this is not
277 actually restored by the syscall exit path, but we put it
278 here for consistency in case of signals. */
279 cregs->gr[28] = 0; /* child */
280
281 /*
282 * We need to differentiate between a user fork and a
283 * kernel fork. We can't use user_mode, because the
284 * the syscall path doesn't save iaoq. Right now
285 * We rely on the fact that kernel_thread passes
286 * in zero for usp.
287 */
288 if (usp == 1) {
289 /* kernel thread */
290 cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
291 /* Must exit via ret_from_kernel_thread in order
292 * to call schedule_tail()
293 */
294 cregs->kpc = (unsigned long) &ret_from_kernel_thread;
295 /*
296 * Copy function and argument to be called from
297 * ret_from_kernel_thread.
298 */
299#ifdef CONFIG_64BIT
300 cregs->gr[27] = pregs->gr[27];
301#endif
302 cregs->gr[26] = pregs->gr[26];
303 cregs->gr[25] = pregs->gr[25];
304 } else {
305 /* user thread */
306 /*
307 * Note that the fork wrappers are responsible
308 * for setting gr[21].
309 */
310
311 /* Use same stack depth as parent */
312 cregs->ksp = (unsigned long)stack
313 + (pregs->gr[21] & (THREAD_SIZE - 1));
314 cregs->gr[30] = usp;
315 if (p->personality == PER_HPUX) {
316#ifdef CONFIG_HPUX
317 cregs->kpc = (unsigned long) &hpux_child_return;
318#else
319 BUG();
320#endif
321 } else {
322 cregs->kpc = (unsigned long) &child_return;
323 }
324 /* Setup thread TLS area from the 4th parameter in clone */
325 if (clone_flags & CLONE_SETTLS)
326 cregs->cr27 = pregs->gr[23];
327
328 }
329
330 return 0;
331}
332
333unsigned long thread_saved_pc(struct task_struct *t)
334{
335 return t->thread.regs.kpc;
336}
337
338/*
339 * sys_execve() executes a new program.
340 */
341
342asmlinkage int sys_execve(struct pt_regs *regs)
343{
344 int error;
345 char *filename;
346
347 filename = getname((const char __user *) regs->gr[26]);
348 error = PTR_ERR(filename);
349 if (IS_ERR(filename))
350 goto out;
351 error = do_execve(filename,
352 (const char __user *const __user *) regs->gr[25],
353 (const char __user *const __user *) regs->gr[24],
354 regs);
355 putname(filename);
356out:
357
358 return error;
359}
360
361extern int __execve(const char *filename,
362 const char *const argv[],
363 const char *const envp[], struct task_struct *task);
364int kernel_execve(const char *filename,
365 const char *const argv[],
366 const char *const envp[])
367{
368 return __execve(filename, argv, envp, current);
369}
370
371unsigned long
372get_wchan(struct task_struct *p)
373{
374 struct unwind_frame_info info;
375 unsigned long ip;
376 int count = 0;
377
378 if (!p || p == current || p->state == TASK_RUNNING)
379 return 0;
380
381 /*
382 * These bracket the sleeping functions..
383 */
384
385 unwind_frame_init_from_blocked_task(&info, p);
386 do {
387 if (unwind_once(&info) < 0)
388 return 0;
389 ip = info.ip;
390 if (!in_sched_functions(ip))
391 return ip;
392 } while (count++ < 16);
393 return 0;
394}
395
396#ifdef CONFIG_64BIT
397void *dereference_function_descriptor(void *ptr)
398{
399 Elf64_Fdesc *desc = ptr;
400 void *p;
401
402 if (!probe_kernel_address(&desc->addr, p))
403 ptr = p;
404 return ptr;
405}
406#endif