[PATCH] h8300 sleep problem
[linux-3.10.git] / arch / h8300 / kernel / process.c
1 /*
2  *  linux/arch/h8300/kernel/process.c
3  *
4  * Yoshinori Sato <ysato@users.sourceforge.jp>
5  *
6  *  Based on:
7  *
8  *  linux/arch/m68knommu/kernel/process.c
9  *
10  *  Copyright (C) 1998  D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
11  *                      Kenneth Albanowski <kjahds@kjahds.com>,
12  *                      The Silver Hammer Group, Ltd.
13  *
14  *  linux/arch/m68k/kernel/process.c
15  *
16  *  Copyright (C) 1995  Hamish Macdonald
17  *
18  *  68060 fixes by Jesper Skov
19  */
20
21 /*
22  * This file handles the architecture-dependent parts of process handling..
23  */
24
25 #include <linux/config.h>
26 #include <linux/errno.h>
27 #include <linux/module.h>
28 #include <linux/sched.h>
29 #include <linux/kernel.h>
30 #include <linux/mm.h>
31 #include <linux/smp.h>
32 #include <linux/smp_lock.h>
33 #include <linux/stddef.h>
34 #include <linux/unistd.h>
35 #include <linux/ptrace.h>
36 #include <linux/slab.h>
37 #include <linux/user.h>
38 #include <linux/a.out.h>
39 #include <linux/interrupt.h>
40 #include <linux/reboot.h>
41
42 #include <asm/uaccess.h>
43 #include <asm/system.h>
44 #include <asm/traps.h>
45 #include <asm/setup.h>
46 #include <asm/pgtable.h>
47
48 asmlinkage void ret_from_fork(void);
49
50 /*
51  * The idle loop on an H8/300..
52  */
53 #if !defined(CONFIG_H8300H_SIM) && !defined(CONFIG_H8S_SIM)
54 void default_idle(void)
55 {
56         while(1) {
57                 if (!need_resched()) {
58                         local_irq_enable();
59                         __asm__("sleep");
60                         local_irq_disable();
61                 }
62                 schedule();
63         }
64 }
65 #else
66 void default_idle(void)
67 {
68         while(1) {
69                 if (need_resched())
70                         schedule();
71         }
72 }
73 #endif
74 void (*idle)(void) = default_idle;
75
76 /*
77  * The idle thread. There's no useful work to be
78  * done, so just try to conserve power and have a
79  * low exit latency (ie sit in a loop waiting for
80  * somebody to say that they'd like to reschedule)
81  */
82 void cpu_idle(void)
83 {
84         idle();
85 }
86
87 void machine_restart(char * __unused)
88 {
89         local_irq_disable();
90         __asm__("jmp @@0"); 
91 }
92
93 EXPORT_SYMBOL(machine_restart);
94
95 void machine_halt(void)
96 {
97         local_irq_disable();
98         __asm__("sleep");
99         for (;;);
100 }
101
102 EXPORT_SYMBOL(machine_halt);
103
104 void machine_power_off(void)
105 {
106         local_irq_disable();
107         __asm__("sleep");
108         for (;;);
109 }
110
111 EXPORT_SYMBOL(machine_power_off);
112
113 void show_regs(struct pt_regs * regs)
114 {
115         printk("\nPC: %08lx  Status: %02x",
116                regs->pc, regs->ccr);
117         printk("\nORIG_ER0: %08lx ER0: %08lx ER1: %08lx",
118                regs->orig_er0, regs->er0, regs->er1);
119         printk("\nER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx",
120                regs->er2, regs->er3, regs->er4, regs->er5);
121         printk("\nER6' %08lx ",regs->er6);
122         if (user_mode(regs))
123                 printk("USP: %08lx\n", rdusp());
124         else
125                 printk("\n");
126 }
127
128 /*
129  * Create a kernel thread
130  */
131 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
132 {
133         long retval;
134         long clone_arg;
135         mm_segment_t fs;
136
137         fs = get_fs();
138         set_fs (KERNEL_DS);
139         clone_arg = flags | CLONE_VM;
140         __asm__("mov.l sp,er3\n\t"
141                 "sub.l er2,er2\n\t"
142                 "mov.l %2,er1\n\t"
143                 "mov.l %1,er0\n\t"
144                 "trapa #0\n\t"
145                 "cmp.l sp,er3\n\t"
146                 "beq 1f\n\t"
147                 "mov.l %4,er0\n\t"
148                 "mov.l %3,er1\n\t"
149                 "jsr @er1\n\t"
150                 "mov.l %5,er0\n\t"
151                 "trapa #0\n"
152                 "1:\n\t"
153                 "mov.l er0,%0"
154                 :"=r"(retval)
155                 :"i"(__NR_clone),"g"(clone_arg),"g"(fn),"g"(arg),"i"(__NR_exit)
156                 :"er0","er1","er2","er3");
157         set_fs (fs);
158         return retval;
159 }
160
161 void flush_thread(void)
162 {
163 }
164
165 /*
166  * "h8300_fork()".. By the time we get here, the
167  * non-volatile registers have also been saved on the
168  * stack. We do some ugly pointer stuff here.. (see
169  * also copy_thread)
170  */
171
172 asmlinkage int h8300_fork(struct pt_regs *regs)
173 {
174         return -EINVAL;
175 }
176
177 asmlinkage int h8300_vfork(struct pt_regs *regs)
178 {
179         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
180 }
181
182 asmlinkage int h8300_clone(struct pt_regs *regs)
183 {
184         unsigned long clone_flags;
185         unsigned long newsp;
186
187         /* syscall2 puts clone_flags in er1 and usp in er2 */
188         clone_flags = regs->er1;
189         newsp = regs->er2;
190         if (!newsp)
191                 newsp  = rdusp();
192         return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
193
194 }
195
196 int copy_thread(int nr, unsigned long clone_flags,
197                 unsigned long usp, unsigned long topstk,
198                  struct task_struct * p, struct pt_regs * regs)
199 {
200         struct pt_regs * childregs;
201
202         childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
203
204         *childregs = *regs;
205         childregs->retpc = (unsigned long) ret_from_fork;
206         childregs->er0 = 0;
207
208         p->thread.usp = usp;
209         p->thread.ksp = (unsigned long)childregs;
210
211         return 0;
212 }
213
214 /*
215  * fill in the user structure for a core dump..
216  */
217 void dump_thread(struct pt_regs * regs, struct user * dump)
218 {
219 /* changed the size calculations - should hopefully work better. lbt */
220         dump->magic = CMAGIC;
221         dump->start_code = 0;
222         dump->start_stack = rdusp() & ~(PAGE_SIZE - 1);
223         dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
224         dump->u_dsize = ((unsigned long) (current->mm->brk +
225                                           (PAGE_SIZE-1))) >> PAGE_SHIFT;
226         dump->u_dsize -= dump->u_tsize;
227         dump->u_ssize = 0;
228
229         dump->u_ar0 = (struct user_regs_struct *)(((int)(&dump->regs)) -((int)(dump)));
230         dump->regs.er0 = regs->er0;
231         dump->regs.er1 = regs->er1;
232         dump->regs.er2 = regs->er2;
233         dump->regs.er3 = regs->er3;
234         dump->regs.er4 = regs->er4;
235         dump->regs.er5 = regs->er5;
236         dump->regs.er6 = regs->er6;
237         dump->regs.orig_er0 = regs->orig_er0;
238         dump->regs.ccr = regs->ccr;
239         dump->regs.pc  = regs->pc;
240 }
241
242 /*
243  * sys_execve() executes a new program.
244  */
245 asmlinkage int sys_execve(char *name, char **argv, char **envp,int dummy,...)
246 {
247         int error;
248         char * filename;
249         struct pt_regs *regs = (struct pt_regs *) ((unsigned char *)&dummy-4);
250
251         lock_kernel();
252         filename = getname(name);
253         error = PTR_ERR(filename);
254         if (IS_ERR(filename))
255                 goto out;
256         error = do_execve(filename, argv, envp, regs);
257         putname(filename);
258 out:
259         unlock_kernel();
260         return error;
261 }
262
263 unsigned long thread_saved_pc(struct task_struct *tsk)
264 {
265         return ((struct pt_regs *)tsk->thread.esp0)->pc;
266 }
267
268 unsigned long get_wchan(struct task_struct *p)
269 {
270         unsigned long fp, pc;
271         unsigned long stack_page;
272         int count = 0;
273         if (!p || p == current || p->state == TASK_RUNNING)
274                 return 0;
275
276         stack_page = (unsigned long)p;
277         fp = ((struct pt_regs *)p->thread.ksp)->er6;
278         do {
279                 if (fp < stack_page+sizeof(struct thread_info) ||
280                     fp >= 8184+stack_page)
281                         return 0;
282                 pc = ((unsigned long *)fp)[1];
283                 if (!in_sched_functions(pc))
284                         return pc;
285                 fp = *(unsigned long *) fp;
286         } while (count++ < 16);
287         return 0;
288 }