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-rw-r--r--arch/frv/kernel/process.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/arch/frv/kernel/process.c b/arch/frv/kernel/process.c
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1/* process.c: FRV specific parts of process handling
2 *
3 * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * - Derived from arch/m68k/kernel/process.c
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#include <linux/config.h>
14#include <linux/errno.h>
15#include <linux/sched.h>
16#include <linux/kernel.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/smp_lock.h>
20#include <linux/stddef.h>
21#include <linux/unistd.h>
22#include <linux/ptrace.h>
23#include <linux/slab.h>
24#include <linux/user.h>
25#include <linux/elf.h>
26#include <linux/reboot.h>
27#include <linux/interrupt.h>
28
29#include <asm/uaccess.h>
30#include <asm/system.h>
31#include <asm/setup.h>
32#include <asm/pgtable.h>
33#include <asm/gdb-stub.h>
34#include <asm/mb-regs.h>
35
36#include "local.h"
37
38asmlinkage void ret_from_fork(void);
39
40#include <asm/pgalloc.h>
41
42struct task_struct *alloc_task_struct(void)
43{
44 struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
45 if (p)
46 atomic_set((atomic_t *)(p+1), 1);
47 return p;
48}
49
50void free_task_struct(struct task_struct *p)
51{
52 if (atomic_dec_and_test((atomic_t *)(p+1)))
53 kfree(p);
54}
55
56static void core_sleep_idle(void)
57{
58#ifdef LED_DEBUG_SLEEP
59 /* Show that we're sleeping... */
60 __set_LEDS(0x55aa);
61#endif
62 frv_cpu_core_sleep();
63#ifdef LED_DEBUG_SLEEP
64 /* ... and that we woke up */
65 __set_LEDS(0);
66#endif
67 mb();
68}
69
70void (*idle)(void) = core_sleep_idle;
71
72/*
73 * The idle thread. There's no useful work to be
74 * done, so just try to conserve power and have a
75 * low exit latency (ie sit in a loop waiting for
76 * somebody to say that they'd like to reschedule)
77 */
78void cpu_idle(void)
79{
80 /* endless idle loop with no priority at all */
81 while (1) {
82 while (!need_resched()) {
83 irq_stat[smp_processor_id()].idle_timestamp = jiffies;
84
85 if (!frv_dma_inprogress && idle)
86 idle();
87 }
88
89 schedule();
90 }
91}
92
93void machine_restart(char * __unused)
94{
95 unsigned long reset_addr;
96#ifdef CONFIG_GDBSTUB
97 gdbstub_exit(0);
98#endif
99
100 if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
101 reset_addr = 0xfefff500;
102 else
103 reset_addr = 0xfeff0500;
104
105 /* Software reset. */
106 asm volatile(" dcef @(gr0,gr0),1 ! membar !"
107 " sti %1,@(%0,0) !"
108 " nop ! nop ! nop ! nop ! nop ! "
109 " nop ! nop ! nop ! nop ! nop ! "
110 " nop ! nop ! nop ! nop ! nop ! "
111 " nop ! nop ! nop ! nop ! nop ! "
112 : : "r" (reset_addr), "r" (1) );
113
114 for (;;)
115 ;
116}
117
118void machine_halt(void)
119{
120#ifdef CONFIG_GDBSTUB
121 gdbstub_exit(0);
122#endif
123
124 for (;;);
125}
126
127void machine_power_off(void)
128{
129#ifdef CONFIG_GDBSTUB
130 gdbstub_exit(0);
131#endif
132
133 for (;;);
134}
135
136void flush_thread(void)
137{
138#if 0 //ndef NO_FPU
139 unsigned long zero = 0;
140#endif
141 set_fs(USER_DS);
142}
143
144inline unsigned long user_stack(const struct pt_regs *regs)
145{
146 while (regs->next_frame)
147 regs = regs->next_frame;
148 return user_mode(regs) ? regs->sp : 0;
149}
150
151asmlinkage int sys_fork(void)
152{
153#ifndef CONFIG_MMU
154 /* fork almost works, enough to trick you into looking elsewhere:-( */
155 return -EINVAL;
156#else
157 return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
158#endif
159}
160
161asmlinkage int sys_vfork(void)
162{
163 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
164 NULL, NULL);
165}
166
167/*****************************************************************************/
168/*
169 * clone a process
170 * - tlsptr is retrieved by copy_thread()
171 */
172asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
173 int __user *parent_tidptr, int __user *child_tidptr,
174 int __user *tlsptr)
175{
176 if (!newsp)
177 newsp = user_stack(__frame);
178 return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
179} /* end sys_clone() */
180
181/*****************************************************************************/
182/*
183 * This gets called before we allocate a new thread and copy
184 * the current task into it.
185 */
186void prepare_to_copy(struct task_struct *tsk)
187{
188 //unlazy_fpu(tsk);
189} /* end prepare_to_copy() */
190
191/*****************************************************************************/
192/*
193 * set up the kernel stack and exception frames for a new process
194 */
195int copy_thread(int nr, unsigned long clone_flags,
196 unsigned long usp, unsigned long topstk,
197 struct task_struct *p, struct pt_regs *regs)
198{
199 struct pt_regs *childregs0, *childregs, *regs0;
200
201 regs0 = __kernel_frame0_ptr;
202 childregs0 = (struct pt_regs *)
203 ((unsigned long) p->thread_info + THREAD_SIZE - USER_CONTEXT_SIZE);
204 childregs = childregs0;
205
206 /* set up the userspace frame (the only place that the USP is stored) */
207 *childregs0 = *regs0;
208
209 childregs0->gr8 = 0;
210 childregs0->sp = usp;
211 childregs0->next_frame = NULL;
212
213 /* set up the return kernel frame if called from kernel_thread() */
214 if (regs != regs0) {
215 childregs--;
216 *childregs = *regs;
217 childregs->sp = (unsigned long) childregs0;
218 childregs->next_frame = childregs0;
219 childregs->gr15 = (unsigned long) p->thread_info;
220 childregs->gr29 = (unsigned long) p;
221 }
222
223 p->set_child_tid = p->clear_child_tid = NULL;
224
225 p->thread.frame = childregs;
226 p->thread.curr = p;
227 p->thread.sp = (unsigned long) childregs;
228 p->thread.fp = 0;
229 p->thread.lr = 0;
230 p->thread.pc = (unsigned long) ret_from_fork;
231 p->thread.frame0 = childregs0;
232
233 /* the new TLS pointer is passed in as arg #5 to sys_clone() */
234 if (clone_flags & CLONE_SETTLS)
235 childregs->gr29 = childregs->gr12;
236
237 save_user_regs(p->thread.user);
238
239 return 0;
240} /* end copy_thread() */
241
242/*
243 * fill in the user structure for a core dump..
244 */
245void dump_thread(struct pt_regs *regs, struct user *dump)
246{
247#if 0
248 /* changed the size calculations - should hopefully work better. lbt */
249 dump->magic = CMAGIC;
250 dump->start_code = 0;
251 dump->start_stack = user_stack(regs) & ~(PAGE_SIZE - 1);
252 dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
253 dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
254 dump->u_dsize -= dump->u_tsize;
255 dump->u_ssize = 0;
256
257 if (dump->start_stack < TASK_SIZE)
258 dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
259
260 dump->regs = *(struct user_context *) regs;
261#endif
262}
263
264/*
265 * sys_execve() executes a new program.
266 */
267asmlinkage int sys_execve(char *name, char **argv, char **envp)
268{
269 int error;
270 char * filename;
271
272 lock_kernel();
273 filename = getname(name);
274 error = PTR_ERR(filename);
275 if (IS_ERR(filename))
276 goto out;
277 error = do_execve(filename, argv, envp, __frame);
278 putname(filename);
279 out:
280 unlock_kernel();
281 return error;
282}
283
284unsigned long get_wchan(struct task_struct *p)
285{
286 struct pt_regs *regs0;
287 unsigned long fp, pc;
288 unsigned long stack_limit;
289 int count = 0;
290 if (!p || p == current || p->state == TASK_RUNNING)
291 return 0;
292
293 stack_limit = (unsigned long) (p + 1);
294 fp = p->thread.fp;
295 regs0 = p->thread.frame0;
296
297 do {
298 if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
299 return 0;
300
301 pc = ((unsigned long *) fp)[2];
302
303 /* FIXME: This depends on the order of these functions. */
304 if (!in_sched_functions(pc))
305 return pc;
306
307 fp = *(unsigned long *) fp;
308 } while (count++ < 16);
309
310 return 0;
311}
312
313unsigned long thread_saved_pc(struct task_struct *tsk)
314{
315 /* Check whether the thread is blocked in resume() */
316 if (in_sched_functions(tsk->thread.pc))
317 return ((unsigned long *)tsk->thread.fp)[2];
318 else
319 return tsk->thread.pc;
320}
321
322int elf_check_arch(const struct elf32_hdr *hdr)
323{
324 unsigned long hsr0 = __get_HSR(0);
325 unsigned long psr = __get_PSR();
326
327 if (hdr->e_machine != EM_FRV)
328 return 0;
329
330 switch (hdr->e_flags & EF_FRV_GPR_MASK) {
331 case EF_FRV_GPR64:
332 if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
333 return 0;
334 case EF_FRV_GPR32:
335 case 0:
336 break;
337 default:
338 return 0;
339 }
340
341 switch (hdr->e_flags & EF_FRV_FPR_MASK) {
342 case EF_FRV_FPR64:
343 if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
344 return 0;
345 case EF_FRV_FPR32:
346 case EF_FRV_FPR_NONE:
347 case 0:
348 break;
349 default:
350 return 0;
351 }
352
353 if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
354 if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
355 PSR_IMPLE(psr) != PSR_IMPLE_FR451)
356 return 0;
357
358 switch (hdr->e_flags & EF_FRV_CPU_MASK) {
359 case EF_FRV_CPU_GENERIC:
360 break;
361 case EF_FRV_CPU_FR300:
362 case EF_FRV_CPU_SIMPLE:
363 case EF_FRV_CPU_TOMCAT:
364 default:
365 return 0;
366 case EF_FRV_CPU_FR400:
367 if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
368 PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
369 PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
370 PSR_IMPLE(psr) != PSR_IMPLE_FR551)
371 return 0;
372 break;
373 case EF_FRV_CPU_FR450:
374 if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
375 return 0;
376 break;
377 case EF_FRV_CPU_FR500:
378 if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
379 return 0;
380 break;
381 case EF_FRV_CPU_FR550:
382 if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
383 return 0;
384 break;
385 }
386
387 return 1;
388}