summaryrefslogtreecommitdiff
path: root/arch/m32r/kernel/process.c
blob: ea13a8f4d8b05aadc691f010435b6fa6ef751a91 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
/*
 *  linux/arch/m32r/kernel/process.c
 *
 *  Copyright (c) 2001, 2002  Hiroyuki Kondo, Hirokazu Takata,
 *                            Hitoshi Yamamoto
 *  Taken from sh version.
 *    Copyright (C) 1995  Linus Torvalds
 *    SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 */

#undef DEBUG_PROCESS
#ifdef DEBUG_PROCESS
#define DPRINTK(fmt, args...)  printk("%s:%d:%s: " fmt, __FILE__, __LINE__, \
  __FUNCTION__, ##args)
#else
#define DPRINTK(fmt, args...)
#endif

/*
 * This file handles the architecture-dependent parts of process handling..
 */

#include <linux/fs.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/hardirq.h>

#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/elf.h>
#include <asm/m32r.h>

#include <linux/err.h>

static int hlt_counter=0;

/*
 * Return saved PC of a blocked thread.
 */
unsigned long thread_saved_pc(struct task_struct *tsk)
{
	return tsk->thread.lr;
}

/*
 * Powermanagement idle function, if any..
 */
void (*pm_idle)(void) = NULL;

void disable_hlt(void)
{
	hlt_counter++;
}

EXPORT_SYMBOL(disable_hlt);

void enable_hlt(void)
{
	hlt_counter--;
}

EXPORT_SYMBOL(enable_hlt);

/*
 * We use this is we don't have any better
 * idle routine..
 */
void default_idle(void)
{
	/* M32R_FIXME: Please use "cpu_sleep" mode.  */
	cpu_relax();
}

/*
 * On SMP it's slightly faster (but much more power-consuming!)
 * to poll the ->work.need_resched flag instead of waiting for the
 * cross-CPU IPI to arrive. Use this option with caution.
 */
static void poll_idle (void)
{
	/* M32R_FIXME */
	cpu_relax();
}

/*
 * The idle thread. There's no useful work to be
 * done, so just try to conserve power and have a
 * low exit latency (ie sit in a loop waiting for
 * somebody to say that they'd like to reschedule)
 */
void cpu_idle (void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		while (!need_resched()) {
			void (*idle)(void) = pm_idle;

			if (!idle)
				idle = default_idle;

			idle();
		}
		schedule();
	}
}

void machine_restart(char *__unused)
{
	printk("Please push reset button!\n");
	while (1)
		cpu_relax();
}

void machine_halt(void)
{
	printk("Please push reset button!\n");
	while (1)
		cpu_relax();
}

void machine_power_off(void)
{
	/* M32R_FIXME */
}

static int __init idle_setup (char *str)
{
	if (!strncmp(str, "poll", 4)) {
		printk("using poll in idle threads.\n");
		pm_idle = poll_idle;
	} else if (!strncmp(str, "sleep", 4)) {
		printk("using sleep in idle threads.\n");
		pm_idle = default_idle;
	}

	return 1;
}

__setup("idle=", idle_setup);

void show_regs(struct pt_regs * regs)
{
	printk("\n");
	printk("BPC[%08lx]:PSW[%08lx]:LR [%08lx]:FP [%08lx]\n", \
	  regs->bpc, regs->psw, regs->lr, regs->fp);
	printk("BBPC[%08lx]:BBPSW[%08lx]:SPU[%08lx]:SPI[%08lx]\n", \
	  regs->bbpc, regs->bbpsw, regs->spu, regs->spi);
	printk("R0 [%08lx]:R1 [%08lx]:R2 [%08lx]:R3 [%08lx]\n", \
	  regs->r0, regs->r1, regs->r2, regs->r3);
	printk("R4 [%08lx]:R5 [%08lx]:R6 [%08lx]:R7 [%08lx]\n", \
	  regs->r4, regs->r5, regs->r6, regs->r7);
	printk("R8 [%08lx]:R9 [%08lx]:R10[%08lx]:R11[%08lx]\n", \
	  regs->r8, regs->r9, regs->r10, regs->r11);
	printk("R12[%08lx]\n", \
	  regs->r12);

#if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
	printk("ACC0H[%08lx]:ACC0L[%08lx]\n", \
	  regs->acc0h, regs->acc0l);
	printk("ACC1H[%08lx]:ACC1L[%08lx]\n", \
	  regs->acc1h, regs->acc1l);
#elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
	printk("ACCH[%08lx]:ACCL[%08lx]\n", \
	  regs->acch, regs->accl);
#else
#error unknown isa configuration
#endif
}

/*
 * Create a kernel thread
 */

/*
 * This is the mechanism for creating a new kernel thread.
 *
 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 * who haven't done an "execve()") should use this: it will work within
 * a system call from a "real" process, but the process memory space will
 * not be free'd until both the parent and the child have exited.
 */
static void kernel_thread_helper(void *nouse, int (*fn)(void *), void *arg)
{
	fn(arg);
	do_exit(-1);
}

int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
	struct pt_regs regs;

	memset(&regs, 0, sizeof (regs));
	regs.r1 = (unsigned long)fn;
	regs.r2 = (unsigned long)arg;

	regs.bpc = (unsigned long)kernel_thread_helper;

	regs.psw = M32R_PSW_BIE;

	/* Ok, create the new process. */
	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL,
		NULL);
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
	/* Nothing to do. */
	DPRINTK("pid = %d\n", current->pid);
}

void flush_thread(void)
{
	DPRINTK("pid = %d\n", current->pid);
	memset(&current->thread.debug_trap, 0, sizeof(struct debug_trap));
}

void release_thread(struct task_struct *dead_task)
{
	/* do nothing */
	DPRINTK("pid = %d\n", dead_task->pid);
}

/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
	return 0; /* Task didn't use the fpu at all. */
}

int copy_thread(int nr, unsigned long clone_flags, unsigned long spu,
	unsigned long unused, struct task_struct *tsk, struct pt_regs *regs)
{
	struct pt_regs *childregs;
	unsigned long sp = (unsigned long)tsk->thread_info + THREAD_SIZE;
	extern void ret_from_fork(void);

	/* Copy registers */
	sp -= sizeof (struct pt_regs);
	childregs = (struct pt_regs *)sp;
	*childregs = *regs;

	childregs->spu = spu;
	childregs->r0 = 0;	/* Child gets zero as return value */
	regs->r0 = tsk->pid;
	tsk->thread.sp = (unsigned long)childregs;
	tsk->thread.lr = (unsigned long)ret_from_fork;

	return 0;
}

/*
 * fill in the user structure for a core dump..
 */
void dump_thread(struct pt_regs * regs, struct user * dump)
{
	/* M32R_FIXME */
}

/*
 * Capture the user space registers if the task is not running (in user space)
 */
int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
{
	/* M32R_FIXME */
	return 1;
}

asmlinkage int sys_fork(unsigned long r0, unsigned long r1, unsigned long r2,
	unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6,
	struct pt_regs regs)
{
#ifdef CONFIG_MMU
	return do_fork(SIGCHLD, regs.spu, &regs, 0, NULL, NULL);
#else
	return -EINVAL;
#endif /* CONFIG_MMU */
}

asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
			 unsigned long parent_tidptr,
			 unsigned long child_tidptr,
			 unsigned long r4, unsigned long r5, unsigned long r6,
			 struct pt_regs regs)
{
	if (!newsp)
		newsp = regs.spu;

	return do_fork(clone_flags, newsp, &regs, 0,
		       (int __user *)parent_tidptr, (int __user *)child_tidptr);
}

/*
 * This is trivial, and on the face of it looks like it
 * could equally well be done in user mode.
 *
 * Not so, for quite unobvious reasons - register pressure.
 * In user mode vfork() cannot have a stack frame, and if
 * done by calling the "clone()" system call directly, you
 * do not have enough call-clobbered registers to hold all
 * the information you need.
 */
asmlinkage int sys_vfork(unsigned long r0, unsigned long r1, unsigned long r2,
	unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6,
	struct pt_regs regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.spu, &regs, 0,
			NULL, NULL);
}

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv,
			  char __user * __user *uenvp,
			  unsigned long r3, unsigned long r4, unsigned long r5,
			  unsigned long r6, struct pt_regs regs)
{
	int error;
	char *filename;

	filename = getname(ufilename);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;

	error = do_execve(filename, uargv, uenvp, &regs);
	if (error == 0) {
		task_lock(current);
		current->ptrace &= ~PT_DTRACE;
		task_unlock(current);
	}
	putname(filename);
out:
	return error;
}

/*
 * These bracket the sleeping functions..
 */
#define first_sched	((unsigned long) scheduling_functions_start_here)
#define last_sched	((unsigned long) scheduling_functions_end_here)

unsigned long get_wchan(struct task_struct *p)
{
	/* M32R_FIXME */
	return (0);
}