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>
29 #include <asm/asm-offsets.h>
30 #include <asm/uaccess.h>
31 #include <asm/setup.h>
32 #include <asm/pgtable.h>
34 #include <asm/gdb-stub.h>
35 #include <asm/mb-regs.h>
39 asmlinkage void ret_from_fork(void);
41 #include <asm/pgalloc.h>
43 void (*pm_power_off)(void);
44 EXPORT_SYMBOL(pm_power_off);
46 static void core_sleep_idle(void)
48 #ifdef LED_DEBUG_SLEEP
49 /* Show that we're sleeping... */
53 #ifdef LED_DEBUG_SLEEP
54 /* ... and that we woke up */
60 void (*idle)(void) = core_sleep_idle;
63 * The idle thread. There's no useful work to be
64 * done, so just try to conserve power and have a
65 * low exit latency (ie sit in a loop waiting for
66 * somebody to say that they'd like to reschedule)
70 /* endless idle loop with no priority at all */
72 while (!need_resched()) {
75 if (!frv_dma_inprogress && idle)
79 schedule_preempt_disabled();
83 void machine_restart(char * __unused)
85 unsigned long reset_addr;
90 if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
91 reset_addr = 0xfefff500;
93 reset_addr = 0xfeff0500;
96 asm volatile(" dcef @(gr0,gr0),1 ! membar !"
98 " nop ! nop ! nop ! nop ! nop ! "
99 " nop ! nop ! nop ! nop ! nop ! "
100 " nop ! nop ! nop ! nop ! nop ! "
101 " nop ! nop ! nop ! nop ! nop ! "
102 : : "r" (reset_addr), "r" (1) );
108 void machine_halt(void)
110 #ifdef CONFIG_GDBSTUB
117 void machine_power_off(void)
119 #ifdef CONFIG_GDBSTUB
126 void flush_thread(void)
131 inline unsigned long user_stack(const struct pt_regs *regs)
133 while (regs->next_frame)
134 regs = regs->next_frame;
135 return user_mode(regs) ? regs->sp : 0;
138 asmlinkage int sys_fork(void)
141 /* fork almost works, enough to trick you into looking elsewhere:-( */
144 return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
148 asmlinkage int sys_vfork(void)
150 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
154 /*****************************************************************************/
157 * - tlsptr is retrieved by copy_thread()
159 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
160 int __user *parent_tidptr, int __user *child_tidptr,
164 newsp = user_stack(__frame);
165 return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
166 } /* end sys_clone() */
169 * set up the kernel stack and exception frames for a new process
171 int copy_thread(unsigned long clone_flags,
172 unsigned long usp, unsigned long topstk,
173 struct task_struct *p, struct pt_regs *regs)
175 struct pt_regs *childregs0, *childregs, *regs0;
177 regs0 = __kernel_frame0_ptr;
178 childregs0 = (struct pt_regs *)
179 (task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
180 childregs = childregs0;
182 /* set up the userspace frame (the only place that the USP is stored) */
183 *childregs0 = *regs0;
186 childregs0->sp = usp;
187 childregs0->next_frame = NULL;
189 /* set up the return kernel frame if called from kernel_thread() */
193 childregs->sp = (unsigned long) childregs0;
194 childregs->next_frame = childregs0;
195 childregs->gr15 = (unsigned long) task_thread_info(p);
196 childregs->gr29 = (unsigned long) p;
199 p->set_child_tid = p->clear_child_tid = NULL;
201 p->thread.frame = childregs;
203 p->thread.sp = (unsigned long) childregs;
206 p->thread.pc = (unsigned long) ret_from_fork;
207 p->thread.frame0 = childregs0;
209 /* the new TLS pointer is passed in as arg #5 to sys_clone() */
210 if (clone_flags & CLONE_SETTLS)
211 childregs->gr29 = childregs->gr12;
213 save_user_regs(p->thread.user);
216 } /* end copy_thread() */
219 * sys_execve() executes a new program.
221 asmlinkage int sys_execve(const char __user *name,
222 const char __user *const __user *argv,
223 const char __user *const __user *envp)
228 filename = getname(name);
229 error = PTR_ERR(filename);
230 if (IS_ERR(filename))
232 error = do_execve(filename, argv, envp, __frame);
237 unsigned long get_wchan(struct task_struct *p)
239 struct pt_regs *regs0;
240 unsigned long fp, pc;
241 unsigned long stack_limit;
243 if (!p || p == current || p->state == TASK_RUNNING)
246 stack_limit = (unsigned long) (p + 1);
248 regs0 = p->thread.frame0;
251 if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
254 pc = ((unsigned long *) fp)[2];
256 /* FIXME: This depends on the order of these functions. */
257 if (!in_sched_functions(pc))
260 fp = *(unsigned long *) fp;
261 } while (count++ < 16);
266 unsigned long thread_saved_pc(struct task_struct *tsk)
268 /* Check whether the thread is blocked in resume() */
269 if (in_sched_functions(tsk->thread.pc))
270 return ((unsigned long *)tsk->thread.fp)[2];
272 return tsk->thread.pc;
275 int elf_check_arch(const struct elf32_hdr *hdr)
277 unsigned long hsr0 = __get_HSR(0);
278 unsigned long psr = __get_PSR();
280 if (hdr->e_machine != EM_FRV)
283 switch (hdr->e_flags & EF_FRV_GPR_MASK) {
285 if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
294 switch (hdr->e_flags & EF_FRV_FPR_MASK) {
296 if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
299 case EF_FRV_FPR_NONE:
306 if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
307 if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
308 PSR_IMPLE(psr) != PSR_IMPLE_FR451)
311 switch (hdr->e_flags & EF_FRV_CPU_MASK) {
312 case EF_FRV_CPU_GENERIC:
314 case EF_FRV_CPU_FR300:
315 case EF_FRV_CPU_SIMPLE:
316 case EF_FRV_CPU_TOMCAT:
319 case EF_FRV_CPU_FR400:
320 if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
321 PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
322 PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
323 PSR_IMPLE(psr) != PSR_IMPLE_FR551)
326 case EF_FRV_CPU_FR450:
327 if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
330 case EF_FRV_CPU_FR500:
331 if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
334 case EF_FRV_CPU_FR550:
335 if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
343 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
346 ¤t->thread.user->f,
347 sizeof(current->thread.user->f));