/*
* linux/arch/m68knommu/kernel/process.c
*
* Copyright (C) 1995 Hamish Macdonald
*
* 68060 fixes by Jesper Skov
*
* uClinux changes
* Copyright (C) 2000-2002, David McCullough <davidm@snapgear.com>
*/
/*
* This file handles the architecture-dependent parts of process handling..
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/traps.h>
#include <asm/machdep.h>
#include <asm/setup.h>
#include <asm/pgtable.h>
asmlinkage void ret_from_fork(void);
/*
* The following aren't currently used.
*/
void (*pm_idle)(void);
EXPORT_SYMBOL(pm_idle);
void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);
/*
* The idle loop on an m68knommu..
*/
static void default_idle(void)
{
local_irq_disable();
while (!need_resched()) {
/* This stop will re-enable interrupts */
__asm__("stop #0x2000" : : : "cc");
local_irq_disable();
}
local_irq_enable();
}
void (*idle)(void) = default_idle;
/*
* 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) {
idle();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
void machine_restart(char * __unused)
{
if (mach_reset)
mach_reset();
for (;;);
}
void machine_halt(void)
{
if (mach_halt)
mach_halt();
for (;;);
}
void machine_power_off(void)
{
if (mach_power_off)
mach_power_off();
for (;;);
}
void show_regs(struct pt_regs * regs)
{
printk(KERN_NOTICE "\n");
printk(KERN_NOTICE "Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
printk(KERN_NOTICE "ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
regs->orig_d0, regs->d0, regs->a2, regs->a1);
printk(KERN_NOTICE "A0: %08lx D5: %08lx D4: %08lx\n",
regs->a0, regs->d5, regs->d4);
printk(KERN_NOTICE "D3: %08lx D2: %08lx D1: %08lx\n",
regs->d3, regs->d2, regs->d1);
if (!(regs->sr & PS_S))
printk(KERN_NOTICE "USP: %08lx\n", rdusp());
}
/*
* Create a kernel thread
*/
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
int retval;
long clone_arg = flags | CLONE_VM;
mm_segment_t fs;
fs = get_fs();
set_fs(KERNEL_DS);
__asm__ __volatile__ (
"movel %%sp, %%d2\n\t"
"movel %5, %%d1\n\t"
"movel %1, %%d0\n\t"
"trap #0\n\t"
"cmpl %%sp, %%d2\n\t"
"jeq 1f\n\t"
"movel %3, %%sp@-\n\t"
"jsr %4@\n\t"
"movel %2, %%d0\n\t"
"trap #0\n"
"1:\n\t"
"movel %%d0, %0\n"
: "=d" (retval)
: "i" (__NR_clone),
"i" (__NR_exit),
"a" (arg),
"a" (fn),
"a" (clone_arg)
: "cc", "%d0", "%d1", "%d2");
set_fs(fs);
return retval;
}
EXPORT_SYMBOL(kernel_thread);
void flush_thread(void)
{
#ifdef CONFIG_FPU
unsigned long zero = 0;
#endif
current->thread.fs = __USER_DS;
#ifdef CONFIG_FPU
if (!FPU_IS_EMU)
asm volatile (".chip 68k/68881\n\t"
"frestore %0\n\t"
".chip 68k" : : "m" (zero));
#endif
}
/*
* "m68k_fork()".. By the time we get here, the
* non-volatile registers have also been saved on the
* stack. We do some ugly pointer stuff here.. (see
* also copy_thread)
*/
asmlinkage int m68k_fork(struct pt_regs *regs)
{
/* fork almost works, enough to trick you into looking elsewhere :-( */
return(-EINVAL);
}
asmlinkage int m68k_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
}
asmlinkage int m68k_clone(struct pt_regs *regs)
{
unsigned long clone_flags;
unsigned long newsp;
/* syscall2 puts clone_flags in d1 and usp in d2 */
clone_flags = regs->d1;
newsp = regs->d2;
if (!newsp)
newsp = rdusp();
return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
}
int copy_thread(unsigned long clone_flags,
unsigned long usp, unsigned long topstk,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
struct switch_stack * childstack, *stack;
unsigned long *retp;
childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
*childregs = *regs;
childregs->d0 = 0;
retp = ((unsigned long *) regs);
stack = ((struct switch_stack *) retp) - 1;
childstack = ((struct switch_stack *) childregs) - 1;
*childstack = *stack;
childstack->retpc = (unsigned long)ret_from_fork;
p->thread.usp = usp;
p->thread.ksp = (unsigned long)childstack;
if (clone_flags & CLONE_SETTLS)
task_thread_info(p)->tp_value = regs->d5;
/*
* Must save the current SFC/DFC value, NOT the value when
* the parent was last descheduled - RGH 10-08-96
*/
p->thread.fs = get_fs().seg;
#ifdef CONFIG_FPU
if (!FPU_IS_EMU) {
/* Copy the current fpu state */
asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
if (p->thread.fpstate[0])
asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
"fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
: : "m" (p->thread.fp[0]), "m" (p->thread.fpcntl[0])
: "memory");
/* Restore the state in case the fpu was busy */
asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
}
#endif
return 0;
}
/* Fill in the fpu structure for a core dump. */
int dump_fpu(struct pt_regs *regs, struct user_m68kfp_struct *fpu)
{
#ifdef CONFIG_FPU
char fpustate[216];
if (FPU_IS_EMU) {
int i;
memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
memcpy(fpu->fpregs, current->thread.fp, 96);
/* Convert internal fpu reg representation
* into long double format
*/
for (i = 0; i < 24; i += 3)
fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
((fpu->fpregs[i] & 0x0000ffff) << 16);
return 1;
}
/* First dump the fpu context to avoid protocol violation. */
asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
if (!fpustate[0])
return 0;
asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
:: "m" (fpu->fpcntl[0])
: "memory");
asm volatile ("fmovemx %/fp0-%/fp7,%0"
:: "m" (fpu->fpregs[0])
: "memory");
#endif
return 1;
}
EXPORT_SYMBOL(dump_fpu);
/*
* Generic dumping code. Used for panic and debug.
*/
void dump(struct pt_regs *fp)
{
unsigned long *sp;
unsigned char *tp;
int i;
printk(KERN_EMERG "\nCURRENT PROCESS:\n\n");
printk(KERN_EMERG "COMM=%s PID=%d\n", current->comm, current->pid);
if (current->mm) {
printk(KERN_EMERG "TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
(int) current->mm->start_code,
(int) current->mm->end_code,
(int) current->mm->start_data,
(int) current->mm->end_data,
(int) current->mm->end_data,
(int) current->mm->brk);
printk(KERN_EMERG "USER-STACK=%08x KERNEL-STACK=%08x\n\n",
(int) current->mm->start_stack,
(int)(((unsigned long) current) + THREAD_SIZE));
}
printk(KERN_EMERG "PC: %08lx\n", fp->pc);
printk(KERN_EMERG "SR: %08lx SP: %08lx\n", (long) fp->sr, (long) fp);
printk(KERN_EMERG "d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
fp->d0, fp->d1, fp->d2, fp->d3);
printk(KERN_EMERG "d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n",
fp->d4, fp->d5, fp->a0, fp->a1);
printk(KERN_EMERG "\nUSP: %08x TRAPFRAME: %p\n",
(unsigned int) rdusp(), fp);
printk(KERN_EMERG "\nCODE:");
tp = ((unsigned char *) fp->pc) - 0x20;
for (sp = (unsigned long *) tp, i = 0; (i < 0x40); i += 4) {
if ((i % 0x10) == 0)
printk(KERN_EMERG "%p: ", tp + i);
printk("%08x ", (int) *sp++);
}
printk(KERN_EMERG "\n");
printk(KERN_EMERG "KERNEL STACK:");
tp = ((unsigned char *) fp) - 0x40;
for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
if ((i % 0x10) == 0)
printk(KERN_EMERG "%p: ", tp + i);
printk("%08x ", (int) *sp++);
}
printk(KERN_EMERG "\n");
printk(KERN_EMERG "USER STACK:");
tp = (unsigned char *) (rdusp() - 0x10);
for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
if ((i % 0x10) == 0)
printk(KERN_EMERG "%p: ", tp + i);
printk("%08x ", (int) *sp++);
}
printk(KERN_EMERG "\n");
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(const char *name,
const char *const *argv,
const char *const *envp)
{
int error;
char * filename;
struct pt_regs *regs = (struct pt_regs *) &name;
filename = getname(name);
error = PTR_ERR(filename);
if (IS_ERR(filename))
return error;
error = do_execve(filename, argv, envp, regs);
putname(filename);
return error;
}
unsigned long get_wchan(struct task_struct *p)
{
unsigned long fp, pc;
unsigned long stack_page;
int count = 0;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
stack_page = (unsigned long)p;
fp = ((struct switch_stack *)p->thread.ksp)->a6;
do {
if (fp < stack_page+sizeof(struct thread_info) ||
fp >= THREAD_SIZE-8+stack_page)
return 0;
pc = ((unsigned long *)fp)[1];
if (!in_sched_functions(pc))
return pc;
fp = *(unsigned long *) fp;
} while (count++ < 16);
return 0;
}
/*
* Return saved PC of a blocked thread.
*/
unsigned long thread_saved_pc(struct task_struct *tsk)
{
struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
/* Check whether the thread is blocked in resume() */
if (in_sched_functions(sw->retpc))
return ((unsigned long *)sw->a6)[1];
else
return sw->retpc;
}
