383 lines
8.4 KiB
C
383 lines
8.4 KiB
C
/* process.c: FRV specific parts of process handling
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*
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* Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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* - Derived from arch/m68k/kernel/process.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/stddef.h>
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#include <linux/unistd.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/user.h>
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#include <linux/elf.h>
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#include <linux/reboot.h>
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#include <linux/interrupt.h>
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#include <asm/asm-offsets.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <asm/setup.h>
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#include <asm/pgtable.h>
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#include <asm/gdb-stub.h>
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#include <asm/mb-regs.h>
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#include "local.h"
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asmlinkage void ret_from_fork(void);
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#include <asm/pgalloc.h>
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void (*pm_power_off)(void);
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EXPORT_SYMBOL(pm_power_off);
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struct task_struct *alloc_task_struct(void)
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{
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struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
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if (p)
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atomic_set((atomic_t *)(p+1), 1);
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return p;
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}
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void free_task_struct(struct task_struct *p)
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{
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if (atomic_dec_and_test((atomic_t *)(p+1)))
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kfree(p);
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}
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static void core_sleep_idle(void)
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{
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#ifdef LED_DEBUG_SLEEP
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/* Show that we're sleeping... */
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__set_LEDS(0x55aa);
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#endif
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frv_cpu_core_sleep();
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#ifdef LED_DEBUG_SLEEP
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/* ... and that we woke up */
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__set_LEDS(0);
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#endif
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mb();
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}
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void (*idle)(void) = core_sleep_idle;
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/*
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* The idle thread. There's no useful work to be
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* done, so just try to conserve power and have a
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* low exit latency (ie sit in a loop waiting for
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* somebody to say that they'd like to reschedule)
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*/
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void cpu_idle(void)
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{
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int cpu = smp_processor_id();
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/* endless idle loop with no priority at all */
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while (1) {
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while (!need_resched()) {
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irq_stat[cpu].idle_timestamp = jiffies;
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if (!frv_dma_inprogress && idle)
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idle();
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}
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preempt_enable_no_resched();
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schedule();
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preempt_disable();
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}
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}
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void machine_restart(char * __unused)
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{
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unsigned long reset_addr;
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#ifdef CONFIG_GDBSTUB
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gdbstub_exit(0);
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#endif
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if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
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reset_addr = 0xfefff500;
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else
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reset_addr = 0xfeff0500;
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/* Software reset. */
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asm volatile(" dcef @(gr0,gr0),1 ! membar !"
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" sti %1,@(%0,0) !"
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" nop ! nop ! nop ! nop ! nop ! "
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" nop ! nop ! nop ! nop ! nop ! "
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" nop ! nop ! nop ! nop ! nop ! "
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" nop ! nop ! nop ! nop ! nop ! "
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: : "r" (reset_addr), "r" (1) );
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for (;;)
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;
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}
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void machine_halt(void)
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{
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#ifdef CONFIG_GDBSTUB
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gdbstub_exit(0);
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#endif
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for (;;);
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}
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void machine_power_off(void)
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{
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#ifdef CONFIG_GDBSTUB
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gdbstub_exit(0);
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#endif
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for (;;);
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}
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void flush_thread(void)
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{
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#if 0 //ndef NO_FPU
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unsigned long zero = 0;
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#endif
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set_fs(USER_DS);
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}
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inline unsigned long user_stack(const struct pt_regs *regs)
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{
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while (regs->next_frame)
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regs = regs->next_frame;
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return user_mode(regs) ? regs->sp : 0;
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}
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asmlinkage int sys_fork(void)
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{
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#ifndef CONFIG_MMU
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/* fork almost works, enough to trick you into looking elsewhere:-( */
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return -EINVAL;
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#else
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return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
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#endif
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}
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asmlinkage int sys_vfork(void)
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{
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return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
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NULL, NULL);
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}
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/*****************************************************************************/
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/*
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* clone a process
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* - tlsptr is retrieved by copy_thread()
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*/
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asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
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int __user *parent_tidptr, int __user *child_tidptr,
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int __user *tlsptr)
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{
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if (!newsp)
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newsp = user_stack(__frame);
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return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
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} /* end sys_clone() */
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/*****************************************************************************/
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/*
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* This gets called before we allocate a new thread and copy
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* the current task into it.
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*/
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void prepare_to_copy(struct task_struct *tsk)
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{
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//unlazy_fpu(tsk);
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} /* end prepare_to_copy() */
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/*****************************************************************************/
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/*
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* set up the kernel stack and exception frames for a new process
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*/
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int copy_thread(int nr, unsigned long clone_flags,
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unsigned long usp, unsigned long topstk,
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struct task_struct *p, struct pt_regs *regs)
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{
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struct pt_regs *childregs0, *childregs, *regs0;
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regs0 = __kernel_frame0_ptr;
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childregs0 = (struct pt_regs *)
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(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
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childregs = childregs0;
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/* set up the userspace frame (the only place that the USP is stored) */
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*childregs0 = *regs0;
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childregs0->gr8 = 0;
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childregs0->sp = usp;
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childregs0->next_frame = NULL;
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/* set up the return kernel frame if called from kernel_thread() */
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if (regs != regs0) {
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childregs--;
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*childregs = *regs;
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childregs->sp = (unsigned long) childregs0;
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childregs->next_frame = childregs0;
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childregs->gr15 = (unsigned long) task_thread_info(p);
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childregs->gr29 = (unsigned long) p;
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}
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p->set_child_tid = p->clear_child_tid = NULL;
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p->thread.frame = childregs;
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p->thread.curr = p;
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p->thread.sp = (unsigned long) childregs;
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p->thread.fp = 0;
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p->thread.lr = 0;
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p->thread.pc = (unsigned long) ret_from_fork;
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p->thread.frame0 = childregs0;
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/* the new TLS pointer is passed in as arg #5 to sys_clone() */
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if (clone_flags & CLONE_SETTLS)
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childregs->gr29 = childregs->gr12;
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save_user_regs(p->thread.user);
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return 0;
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} /* end copy_thread() */
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/*
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* sys_execve() executes a new program.
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*/
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asmlinkage int sys_execve(char __user *name, char __user * __user *argv, char __user * __user *envp)
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{
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int error;
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char * filename;
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lock_kernel();
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filename = getname(name);
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error = PTR_ERR(filename);
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if (IS_ERR(filename))
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goto out;
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error = do_execve(filename, argv, envp, __frame);
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putname(filename);
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out:
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unlock_kernel();
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return error;
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}
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unsigned long get_wchan(struct task_struct *p)
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{
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struct pt_regs *regs0;
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unsigned long fp, pc;
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unsigned long stack_limit;
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int count = 0;
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if (!p || p == current || p->state == TASK_RUNNING)
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return 0;
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stack_limit = (unsigned long) (p + 1);
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fp = p->thread.fp;
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regs0 = p->thread.frame0;
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do {
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if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
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return 0;
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pc = ((unsigned long *) fp)[2];
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/* FIXME: This depends on the order of these functions. */
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if (!in_sched_functions(pc))
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return pc;
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fp = *(unsigned long *) fp;
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} while (count++ < 16);
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return 0;
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}
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unsigned long thread_saved_pc(struct task_struct *tsk)
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{
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/* Check whether the thread is blocked in resume() */
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if (in_sched_functions(tsk->thread.pc))
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return ((unsigned long *)tsk->thread.fp)[2];
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else
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return tsk->thread.pc;
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}
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int elf_check_arch(const struct elf32_hdr *hdr)
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{
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unsigned long hsr0 = __get_HSR(0);
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unsigned long psr = __get_PSR();
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if (hdr->e_machine != EM_FRV)
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return 0;
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switch (hdr->e_flags & EF_FRV_GPR_MASK) {
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case EF_FRV_GPR64:
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if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
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return 0;
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case EF_FRV_GPR32:
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case 0:
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break;
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default:
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return 0;
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}
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switch (hdr->e_flags & EF_FRV_FPR_MASK) {
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case EF_FRV_FPR64:
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if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
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return 0;
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case EF_FRV_FPR32:
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case EF_FRV_FPR_NONE:
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case 0:
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break;
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default:
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return 0;
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}
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if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
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if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
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PSR_IMPLE(psr) != PSR_IMPLE_FR451)
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return 0;
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switch (hdr->e_flags & EF_FRV_CPU_MASK) {
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case EF_FRV_CPU_GENERIC:
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break;
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case EF_FRV_CPU_FR300:
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case EF_FRV_CPU_SIMPLE:
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case EF_FRV_CPU_TOMCAT:
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default:
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return 0;
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case EF_FRV_CPU_FR400:
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if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
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PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
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PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
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PSR_IMPLE(psr) != PSR_IMPLE_FR551)
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return 0;
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break;
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case EF_FRV_CPU_FR450:
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if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
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return 0;
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break;
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case EF_FRV_CPU_FR500:
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if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
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return 0;
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break;
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case EF_FRV_CPU_FR550:
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if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
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return 0;
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break;
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}
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return 1;
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}
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int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
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{
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memcpy(fpregs,
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¤t->thread.user->f,
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sizeof(current->thread.user->f));
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return 1;
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}
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