1 /* process.c: FRV specific parts of process handling
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
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.
13 #include <linux/module.h>
14 #include <linux/errno.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
18 #include <linux/smp.h>
19 #include <linux/stddef.h>
20 #include <linux/unistd.h>
21 #include <linux/ptrace.h>
22 #include <linux/slab.h>
23 #include <linux/user.h>
24 #include <linux/elf.h>
25 #include <linux/reboot.h>
26 #include <linux/interrupt.h>
27 #include <linux/pagemap.h>
28 #include <linux/rcupdate.h>
30 #include <asm/asm-offsets.h>
31 #include <asm/uaccess.h>
32 #include <asm/setup.h>
33 #include <asm/pgtable.h>
35 #include <asm/gdb-stub.h>
36 #include <asm/mb-regs.h>
40 asmlinkage void ret_from_fork(void);
41 asmlinkage void ret_from_kernel_thread(void);
43 #include <asm/pgalloc.h>
45 void (*pm_power_off)(void);
46 EXPORT_SYMBOL(pm_power_off);
48 static void core_sleep_idle(void)
50 #ifdef LED_DEBUG_SLEEP
51 /* Show that we're sleeping... */
55 #ifdef LED_DEBUG_SLEEP
56 /* ... and that we woke up */
62 void (*idle)(void) = core_sleep_idle;
65 * The idle thread. There's no useful work to be
66 * done, so just try to conserve power and have a
67 * low exit latency (ie sit in a loop waiting for
68 * somebody to say that they'd like to reschedule)
72 /* endless idle loop with no priority at all */
75 while (!need_resched()) {
78 if (!frv_dma_inprogress && idle)
83 schedule_preempt_disabled();
87 void machine_restart(char * __unused)
89 unsigned long reset_addr;
94 if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
95 reset_addr = 0xfefff500;
97 reset_addr = 0xfeff0500;
100 asm volatile(" dcef @(gr0,gr0),1 ! membar !"
102 " nop ! nop ! nop ! nop ! nop ! "
103 " nop ! nop ! nop ! nop ! nop ! "
104 " nop ! nop ! nop ! nop ! nop ! "
105 " nop ! nop ! nop ! nop ! nop ! "
106 : : "r" (reset_addr), "r" (1) );
112 void machine_halt(void)
114 #ifdef CONFIG_GDBSTUB
121 void machine_power_off(void)
123 #ifdef CONFIG_GDBSTUB
130 void flush_thread(void)
135 inline unsigned long user_stack(const struct pt_regs *regs)
137 while (regs->next_frame)
138 regs = regs->next_frame;
139 return user_mode(regs) ? regs->sp : 0;
142 asmlinkage int sys_fork(void)
145 /* fork almost works, enough to trick you into looking elsewhere:-( */
148 return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
152 asmlinkage int sys_vfork(void)
154 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
158 /*****************************************************************************/
161 * - tlsptr is retrieved by copy_thread()
163 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
164 int __user *parent_tidptr, int __user *child_tidptr,
168 newsp = user_stack(__frame);
169 return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
170 } /* end sys_clone() */
173 * set up the kernel stack and exception frames for a new process
175 int copy_thread(unsigned long clone_flags,
176 unsigned long usp, unsigned long arg,
177 struct task_struct *p, struct pt_regs *regs)
179 struct pt_regs *childregs;
181 childregs = (struct pt_regs *)
182 (task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
184 /* set up the userspace frame (the only place that the USP is stored) */
185 *childregs = *__kernel_frame0_ptr;
187 p->set_child_tid = p->clear_child_tid = NULL;
189 p->thread.frame = childregs;
191 p->thread.sp = (unsigned long) childregs;
194 p->thread.frame0 = childregs;
196 if (unlikely(!regs)) {
197 childregs->gr9 = usp; /* function */
198 childregs->gr8 = arg;
199 p->thread.pc = (unsigned long) ret_from_kernel_thread;
200 save_user_regs(p->thread.user);
204 /* set up the userspace frame (the only place that the USP is stored) */
208 childregs->next_frame = NULL;
210 p->thread.pc = (unsigned long) ret_from_fork;
212 /* the new TLS pointer is passed in as arg #5 to sys_clone() */
213 if (clone_flags & CLONE_SETTLS)
214 childregs->gr29 = childregs->gr12;
216 save_user_regs(p->thread.user);
219 } /* end copy_thread() */
221 unsigned long get_wchan(struct task_struct *p)
223 struct pt_regs *regs0;
224 unsigned long fp, pc;
225 unsigned long stack_limit;
227 if (!p || p == current || p->state == TASK_RUNNING)
230 stack_limit = (unsigned long) (p + 1);
232 regs0 = p->thread.frame0;
235 if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
238 pc = ((unsigned long *) fp)[2];
240 /* FIXME: This depends on the order of these functions. */
241 if (!in_sched_functions(pc))
244 fp = *(unsigned long *) fp;
245 } while (count++ < 16);
250 unsigned long thread_saved_pc(struct task_struct *tsk)
252 /* Check whether the thread is blocked in resume() */
253 if (in_sched_functions(tsk->thread.pc))
254 return ((unsigned long *)tsk->thread.fp)[2];
256 return tsk->thread.pc;
259 int elf_check_arch(const struct elf32_hdr *hdr)
261 unsigned long hsr0 = __get_HSR(0);
262 unsigned long psr = __get_PSR();
264 if (hdr->e_machine != EM_FRV)
267 switch (hdr->e_flags & EF_FRV_GPR_MASK) {
269 if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
278 switch (hdr->e_flags & EF_FRV_FPR_MASK) {
280 if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
283 case EF_FRV_FPR_NONE:
290 if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
291 if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
292 PSR_IMPLE(psr) != PSR_IMPLE_FR451)
295 switch (hdr->e_flags & EF_FRV_CPU_MASK) {
296 case EF_FRV_CPU_GENERIC:
298 case EF_FRV_CPU_FR300:
299 case EF_FRV_CPU_SIMPLE:
300 case EF_FRV_CPU_TOMCAT:
303 case EF_FRV_CPU_FR400:
304 if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
305 PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
306 PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
307 PSR_IMPLE(psr) != PSR_IMPLE_FR551)
310 case EF_FRV_CPU_FR450:
311 if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
314 case EF_FRV_CPU_FR500:
315 if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
318 case EF_FRV_CPU_FR550:
319 if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
327 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
330 ¤t->thread.user->f,
331 sizeof(current->thread.user->f));