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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/m68k/kernel/process.c
4 *
5 * Copyright (C) 1995 Hamish Macdonald
6 *
7 * 68060 fixes by Jesper Skov
8 */
9
10/*
11 * This file handles the architecture-dependent parts of process handling..
12 */
13
14#include <linux/errno.h>
15#include <linux/module.h>
16#include <linux/sched.h>
17#include <linux/sched/debug.h>
18#include <linux/sched/task.h>
19#include <linux/sched/task_stack.h>
20#include <linux/kernel.h>
21#include <linux/mm.h>
22#include <linux/slab.h>
23#include <linux/fs.h>
24#include <linux/smp.h>
25#include <linux/stddef.h>
26#include <linux/unistd.h>
27#include <linux/ptrace.h>
28#include <linux/user.h>
29#include <linux/reboot.h>
30#include <linux/init_task.h>
31#include <linux/mqueue.h>
32#include <linux/rcupdate.h>
33#include <linux/syscalls.h>
34#include <linux/uaccess.h>
35
36#include <asm/traps.h>
37#include <asm/machdep.h>
38#include <asm/setup.h>
39
40
41asmlinkage void ret_from_fork(void);
42asmlinkage void ret_from_kernel_thread(void);
43
44void arch_cpu_idle(void)
45{
46#if defined(MACH_ATARI_ONLY)
47 /* block out HSYNC on the atari (falcon) */
48 __asm__("stop #0x2200" : : : "cc");
49#else
50 __asm__("stop #0x2000" : : : "cc");
51#endif
52}
53
54void machine_restart(char * __unused)
55{
56 if (mach_reset)
57 mach_reset();
58 for (;;);
59}
60
61void machine_halt(void)
62{
63 if (mach_halt)
64 mach_halt();
65 for (;;);
66}
67
68void machine_power_off(void)
69{
70 if (mach_power_off)
71 mach_power_off();
72 for (;;);
73}
74
75void (*pm_power_off)(void) = machine_power_off;
76EXPORT_SYMBOL(pm_power_off);
77
78void show_regs(struct pt_regs * regs)
79{
80 pr_info("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
81 regs->format, regs->vector, regs->pc, regs->sr,
82 print_tainted());
83 pr_info("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
84 regs->orig_d0, regs->d0, regs->a2, regs->a1);
85 pr_info("A0: %08lx D5: %08lx D4: %08lx\n", regs->a0, regs->d5,
86 regs->d4);
87 pr_info("D3: %08lx D2: %08lx D1: %08lx\n", regs->d3, regs->d2,
88 regs->d1);
89 if (!(regs->sr & PS_S))
90 pr_info("USP: %08lx\n", rdusp());
91}
92
93void flush_thread(void)
94{
95 current->thread.fs = __USER_DS;
96#ifdef CONFIG_FPU
97 if (!FPU_IS_EMU) {
98 unsigned long zero = 0;
99 asm volatile("frestore %0": :"m" (zero));
100 }
101#endif
102}
103
104/*
105 * Why not generic sys_clone, you ask? m68k passes all arguments on stack.
106 * And we need all registers saved, which means a bunch of stuff pushed
107 * on top of pt_regs, which means that sys_clone() arguments would be
108 * buried. We could, of course, copy them, but it's too costly for no
109 * good reason - generic clone() would have to copy them *again* for
110 * _do_fork() anyway. So in this case it's actually better to pass pt_regs *
111 * and extract arguments for _do_fork() from there. Eventually we might
112 * go for calling _do_fork() directly from the wrapper, but only after we
113 * are finished with _do_fork() prototype conversion.
114 */
115asmlinkage int m68k_clone(struct pt_regs *regs)
116{
117 /* regs will be equal to current_pt_regs() */
118 struct kernel_clone_args args = {
119 .flags = regs->d1 & ~CSIGNAL,
120 .pidfd = (int __user *)regs->d3,
121 .child_tid = (int __user *)regs->d4,
122 .parent_tid = (int __user *)regs->d3,
123 .exit_signal = regs->d1 & CSIGNAL,
124 .stack = regs->d2,
125 .tls = regs->d5,
126 };
127
128 return _do_fork(&args);
129}
130
131/*
132 * Because extra registers are saved on the stack after the sys_clone3()
133 * arguments, this C wrapper extracts them from pt_regs * and then calls the
134 * generic sys_clone3() implementation.
135 */
136asmlinkage int m68k_clone3(struct pt_regs *regs)
137{
138 return sys_clone3((struct clone_args __user *)regs->d1, regs->d2);
139}
140
141int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
142 struct task_struct *p, unsigned long tls)
143{
144 struct fork_frame {
145 struct switch_stack sw;
146 struct pt_regs regs;
147 } *frame;
148
149 frame = (struct fork_frame *) (task_stack_page(p) + THREAD_SIZE) - 1;
150
151 p->thread.ksp = (unsigned long)frame;
152 p->thread.esp0 = (unsigned long)&frame->regs;
153
154 /*
155 * Must save the current SFC/DFC value, NOT the value when
156 * the parent was last descheduled - RGH 10-08-96
157 */
158 p->thread.fs = get_fs().seg;
159
160 if (unlikely(p->flags & PF_KTHREAD)) {
161 /* kernel thread */
162 memset(frame, 0, sizeof(struct fork_frame));
163 frame->regs.sr = PS_S;
164 frame->sw.a3 = usp; /* function */
165 frame->sw.d7 = arg;
166 frame->sw.retpc = (unsigned long)ret_from_kernel_thread;
167 p->thread.usp = 0;
168 return 0;
169 }
170 memcpy(frame, container_of(current_pt_regs(), struct fork_frame, regs),
171 sizeof(struct fork_frame));
172 frame->regs.d0 = 0;
173 frame->sw.retpc = (unsigned long)ret_from_fork;
174 p->thread.usp = usp ?: rdusp();
175
176 if (clone_flags & CLONE_SETTLS)
177 task_thread_info(p)->tp_value = tls;
178
179#ifdef CONFIG_FPU
180 if (!FPU_IS_EMU) {
181 /* Copy the current fpu state */
182 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
183
184 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
185 if (CPU_IS_COLDFIRE) {
186 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
187 "fmovel %/fpiar,%1\n\t"
188 "fmovel %/fpcr,%2\n\t"
189 "fmovel %/fpsr,%3"
190 :
191 : "m" (p->thread.fp[0]),
192 "m" (p->thread.fpcntl[0]),
193 "m" (p->thread.fpcntl[1]),
194 "m" (p->thread.fpcntl[2])
195 : "memory");
196 } else {
197 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
198 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
199 :
200 : "m" (p->thread.fp[0]),
201 "m" (p->thread.fpcntl[0])
202 : "memory");
203 }
204 }
205
206 /* Restore the state in case the fpu was busy */
207 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
208 }
209#endif /* CONFIG_FPU */
210
211 return 0;
212}
213
214/* Fill in the fpu structure for a core dump. */
215int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
216{
217 if (FPU_IS_EMU) {
218 int i;
219
220 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
221 memcpy(fpu->fpregs, current->thread.fp, 96);
222 /* Convert internal fpu reg representation
223 * into long double format
224 */
225 for (i = 0; i < 24; i += 3)
226 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
227 ((fpu->fpregs[i] & 0x0000ffff) << 16);
228 return 1;
229 }
230
231 if (IS_ENABLED(CONFIG_FPU)) {
232 char fpustate[216];
233
234 /* First dump the fpu context to avoid protocol violation. */
235 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
236 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
237 return 0;
238
239 if (CPU_IS_COLDFIRE) {
240 asm volatile ("fmovel %/fpiar,%0\n\t"
241 "fmovel %/fpcr,%1\n\t"
242 "fmovel %/fpsr,%2\n\t"
243 "fmovemd %/fp0-%/fp7,%3"
244 :
245 : "m" (fpu->fpcntl[0]),
246 "m" (fpu->fpcntl[1]),
247 "m" (fpu->fpcntl[2]),
248 "m" (fpu->fpregs[0])
249 : "memory");
250 } else {
251 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
252 :
253 : "m" (fpu->fpcntl[0])
254 : "memory");
255 asm volatile ("fmovemx %/fp0-%/fp7,%0"
256 :
257 : "m" (fpu->fpregs[0])
258 : "memory");
259 }
260 }
261
262 return 1;
263}
264EXPORT_SYMBOL(dump_fpu);
265
266unsigned long get_wchan(struct task_struct *p)
267{
268 unsigned long fp, pc;
269 unsigned long stack_page;
270 int count = 0;
271 if (!p || p == current || p->state == TASK_RUNNING)
272 return 0;
273
274 stack_page = (unsigned long)task_stack_page(p);
275 fp = ((struct switch_stack *)p->thread.ksp)->a6;
276 do {
277 if (fp < stack_page+sizeof(struct thread_info) ||
278 fp >= 8184+stack_page)
279 return 0;
280 pc = ((unsigned long *)fp)[1];
281 if (!in_sched_functions(pc))
282 return pc;
283 fp = *(unsigned long *) fp;
284 } while (count++ < 16);
285 return 0;
286}
1/*
2 * linux/arch/m68k/kernel/process.c
3 *
4 * Copyright (C) 1995 Hamish Macdonald
5 *
6 * 68060 fixes by Jesper Skov
7 */
8
9/*
10 * This file handles the architecture-dependent parts of process handling..
11 */
12
13#include <linux/errno.h>
14#include <linux/module.h>
15#include <linux/sched.h>
16#include <linux/kernel.h>
17#include <linux/mm.h>
18#include <linux/slab.h>
19#include <linux/fs.h>
20#include <linux/smp.h>
21#include <linux/stddef.h>
22#include <linux/unistd.h>
23#include <linux/ptrace.h>
24#include <linux/user.h>
25#include <linux/reboot.h>
26#include <linux/init_task.h>
27#include <linux/mqueue.h>
28#include <linux/rcupdate.h>
29
30#include <asm/uaccess.h>
31#include <asm/traps.h>
32#include <asm/machdep.h>
33#include <asm/setup.h>
34#include <asm/pgtable.h>
35
36
37asmlinkage void ret_from_fork(void);
38asmlinkage void ret_from_kernel_thread(void);
39
40
41/*
42 * Return saved PC from a blocked thread
43 */
44unsigned long thread_saved_pc(struct task_struct *tsk)
45{
46 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
47 /* Check whether the thread is blocked in resume() */
48 if (in_sched_functions(sw->retpc))
49 return ((unsigned long *)sw->a6)[1];
50 else
51 return sw->retpc;
52}
53
54void arch_cpu_idle(void)
55{
56#if defined(MACH_ATARI_ONLY)
57 /* block out HSYNC on the atari (falcon) */
58 __asm__("stop #0x2200" : : : "cc");
59#else
60 __asm__("stop #0x2000" : : : "cc");
61#endif
62}
63
64void machine_restart(char * __unused)
65{
66 if (mach_reset)
67 mach_reset();
68 for (;;);
69}
70
71void machine_halt(void)
72{
73 if (mach_halt)
74 mach_halt();
75 for (;;);
76}
77
78void machine_power_off(void)
79{
80 if (mach_power_off)
81 mach_power_off();
82 for (;;);
83}
84
85void (*pm_power_off)(void) = machine_power_off;
86EXPORT_SYMBOL(pm_power_off);
87
88void show_regs(struct pt_regs * regs)
89{
90 printk("\n");
91 printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
92 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
93 printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
94 regs->orig_d0, regs->d0, regs->a2, regs->a1);
95 printk("A0: %08lx D5: %08lx D4: %08lx\n",
96 regs->a0, regs->d5, regs->d4);
97 printk("D3: %08lx D2: %08lx D1: %08lx\n",
98 regs->d3, regs->d2, regs->d1);
99 if (!(regs->sr & PS_S))
100 printk("USP: %08lx\n", rdusp());
101}
102
103void flush_thread(void)
104{
105 current->thread.fs = __USER_DS;
106#ifdef CONFIG_FPU
107 if (!FPU_IS_EMU) {
108 unsigned long zero = 0;
109 asm volatile("frestore %0": :"m" (zero));
110 }
111#endif
112}
113
114/*
115 * Why not generic sys_clone, you ask? m68k passes all arguments on stack.
116 * And we need all registers saved, which means a bunch of stuff pushed
117 * on top of pt_regs, which means that sys_clone() arguments would be
118 * buried. We could, of course, copy them, but it's too costly for no
119 * good reason - generic clone() would have to copy them *again* for
120 * do_fork() anyway. So in this case it's actually better to pass pt_regs *
121 * and extract arguments for do_fork() from there. Eventually we might
122 * go for calling do_fork() directly from the wrapper, but only after we
123 * are finished with do_fork() prototype conversion.
124 */
125asmlinkage int m68k_clone(struct pt_regs *regs)
126{
127 /* regs will be equal to current_pt_regs() */
128 return do_fork(regs->d1, regs->d2, 0,
129 (int __user *)regs->d3, (int __user *)regs->d4);
130}
131
132int copy_thread(unsigned long clone_flags, unsigned long usp,
133 unsigned long arg, struct task_struct *p)
134{
135 struct fork_frame {
136 struct switch_stack sw;
137 struct pt_regs regs;
138 } *frame;
139
140 frame = (struct fork_frame *) (task_stack_page(p) + THREAD_SIZE) - 1;
141
142 p->thread.ksp = (unsigned long)frame;
143 p->thread.esp0 = (unsigned long)&frame->regs;
144
145 /*
146 * Must save the current SFC/DFC value, NOT the value when
147 * the parent was last descheduled - RGH 10-08-96
148 */
149 p->thread.fs = get_fs().seg;
150
151 if (unlikely(p->flags & PF_KTHREAD)) {
152 /* kernel thread */
153 memset(frame, 0, sizeof(struct fork_frame));
154 frame->regs.sr = PS_S;
155 frame->sw.a3 = usp; /* function */
156 frame->sw.d7 = arg;
157 frame->sw.retpc = (unsigned long)ret_from_kernel_thread;
158 p->thread.usp = 0;
159 return 0;
160 }
161 memcpy(frame, container_of(current_pt_regs(), struct fork_frame, regs),
162 sizeof(struct fork_frame));
163 frame->regs.d0 = 0;
164 frame->sw.retpc = (unsigned long)ret_from_fork;
165 p->thread.usp = usp ?: rdusp();
166
167 if (clone_flags & CLONE_SETTLS)
168 task_thread_info(p)->tp_value = frame->regs.d5;
169
170#ifdef CONFIG_FPU
171 if (!FPU_IS_EMU) {
172 /* Copy the current fpu state */
173 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
174
175 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
176 if (CPU_IS_COLDFIRE) {
177 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
178 "fmovel %/fpiar,%1\n\t"
179 "fmovel %/fpcr,%2\n\t"
180 "fmovel %/fpsr,%3"
181 :
182 : "m" (p->thread.fp[0]),
183 "m" (p->thread.fpcntl[0]),
184 "m" (p->thread.fpcntl[1]),
185 "m" (p->thread.fpcntl[2])
186 : "memory");
187 } else {
188 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
189 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
190 :
191 : "m" (p->thread.fp[0]),
192 "m" (p->thread.fpcntl[0])
193 : "memory");
194 }
195 }
196
197 /* Restore the state in case the fpu was busy */
198 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
199 }
200#endif /* CONFIG_FPU */
201
202 return 0;
203}
204
205/* Fill in the fpu structure for a core dump. */
206#ifdef CONFIG_FPU
207int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
208{
209 char fpustate[216];
210
211 if (FPU_IS_EMU) {
212 int i;
213
214 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
215 memcpy(fpu->fpregs, current->thread.fp, 96);
216 /* Convert internal fpu reg representation
217 * into long double format
218 */
219 for (i = 0; i < 24; i += 3)
220 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
221 ((fpu->fpregs[i] & 0x0000ffff) << 16);
222 return 1;
223 }
224
225 /* First dump the fpu context to avoid protocol violation. */
226 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
227 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
228 return 0;
229
230 if (CPU_IS_COLDFIRE) {
231 asm volatile ("fmovel %/fpiar,%0\n\t"
232 "fmovel %/fpcr,%1\n\t"
233 "fmovel %/fpsr,%2\n\t"
234 "fmovemd %/fp0-%/fp7,%3"
235 :
236 : "m" (fpu->fpcntl[0]),
237 "m" (fpu->fpcntl[1]),
238 "m" (fpu->fpcntl[2]),
239 "m" (fpu->fpregs[0])
240 : "memory");
241 } else {
242 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
243 :
244 : "m" (fpu->fpcntl[0])
245 : "memory");
246 asm volatile ("fmovemx %/fp0-%/fp7,%0"
247 :
248 : "m" (fpu->fpregs[0])
249 : "memory");
250 }
251
252 return 1;
253}
254EXPORT_SYMBOL(dump_fpu);
255#endif /* CONFIG_FPU */
256
257unsigned long get_wchan(struct task_struct *p)
258{
259 unsigned long fp, pc;
260 unsigned long stack_page;
261 int count = 0;
262 if (!p || p == current || p->state == TASK_RUNNING)
263 return 0;
264
265 stack_page = (unsigned long)task_stack_page(p);
266 fp = ((struct switch_stack *)p->thread.ksp)->a6;
267 do {
268 if (fp < stack_page+sizeof(struct thread_info) ||
269 fp >= 8184+stack_page)
270 return 0;
271 pc = ((unsigned long *)fp)[1];
272 if (!in_sched_functions(pc))
273 return pc;
274 fp = *(unsigned long *) fp;
275 } while (count++ < 16);
276 return 0;
277}