/*
* PARISC Architecture-dependent parts of process handling
* based on the work for i386
*
* Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
* Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
* Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
* Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
* Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
* Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
* Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
* Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
* Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
* Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
* Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
* Copyright (C) 2001-2007 Helge Deller <deller at parisc-linux.org>
* Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdarg.h>
#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <asm/io.h>
#include <asm/asm-offsets.h>
#include <asm/pdc.h>
#include <asm/pdc_chassis.h>
#include <asm/pgalloc.h>
#include <asm/unwind.h>
#include <asm/sections.h>
/*
* 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)
{
set_thread_flag(TIF_POLLING_NRFLAG);
/* endless idle loop with no priority at all */
while (1) {
while (!need_resched())
barrier();
preempt_enable_no_resched();
schedule();
preempt_disable();
check_pgt_cache();
}
}
#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
#define CMD_RESET 5 /* reset any module */
/*
** The Wright Brothers and Gecko systems have a H/W problem
** (Lasi...'nuf said) may cause a broadcast reset to lockup
** the system. An HVERSION dependent PDC call was developed
** to perform a "safe", platform specific broadcast reset instead
** of kludging up all the code.
**
** Older machines which do not implement PDC_BROADCAST_RESET will
** return (with an error) and the regular broadcast reset can be
** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
** the PDC call will not return (the system will be reset).
*/
void machine_restart(char *cmd)
{
#ifdef FASTBOOT_SELFTEST_SUPPORT
/*
** If user has modified the Firmware Selftest Bitmap,
** run the tests specified in the bitmap after the
** system is rebooted w/PDC_DO_RESET.
**
** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
**
** Using "directed resets" at each processor with the MEM_TOC
** vector cleared will also avoid running destructive
** memory self tests. (Not implemented yet)
*/
if (ftc_bitmap) {
pdc_do_firm_test_reset(ftc_bitmap);
}
#endif
/* set up a new led state on systems shipped with a LED State panel */
pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
/* "Normal" system reset */
pdc_do_reset();
/* Nope...box should reset with just CMD_RESET now */
gsc_writel(CMD_RESET, COMMAND_GLOBAL);
/* Wait for RESET to lay us to rest. */
while (1) ;
}
void machine_halt(void)
{
/*
** The LED/ChassisCodes are updated by the led_halt()
** function, called by the reboot notifier chain.
*/
}
void (*chassis_power_off)(void);
/*
* This routine is called from sys_reboot to actually turn off the
* machine
*/
void machine_power_off(void)
{
/* If there is a registered power off handler, call it. */
if (chassis_power_off)
chassis_power_off();
/* Put the soft power button back under hardware control.
* If the user had already pressed the power button, the
* following call will immediately power off. */
pdc_soft_power_button(0);
pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
/* It seems we have no way to power the system off via
* software. The user has to press the button himself. */
printk(KERN_EMERG "System shut down completed.\n"
"Please power this system off now.");
}
void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);
/*
* Create a kernel thread
*/
extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
/*
* FIXME: Once we are sure we don't need any debug here,
* kernel_thread can become a #define.
*/
return __kernel_thread(fn, arg, flags);
}
EXPORT_SYMBOL(kernel_thread);
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
}
void flush_thread(void)
{
/* Only needs to handle fpu stuff or perf monitors.
** REVISIT: several arches implement a "lazy fpu state".
*/
set_fs(USER_DS);
}
void release_thread(struct task_struct *dead_task)
{
}
/*
* Fill in the FPU structure for a core dump.
*/
int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
{
if (regs == NULL)
return 0;
memcpy(r, regs->fr, sizeof *r);
return 1;
}
int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
{
memcpy(r, tsk->thread.regs.fr, sizeof(*r));
return 1;
}
/* Note that "fork()" is implemented in terms of clone, with
parameters (SIGCHLD, regs->gr[30], regs). */
int
sys_clone(unsigned long clone_flags, unsigned long usp,
struct pt_regs *regs)
{
/* Arugments from userspace are:
r26 = Clone flags.
r25 = Child stack.
r24 = parent_tidptr.
r23 = Is the TLS storage descriptor
r22 = child_tidptr
However, these last 3 args are only examined
if the proper flags are set. */
int __user *parent_tidptr = (int __user *)regs->gr[24];
int __user *child_tidptr = (int __user *)regs->gr[22];
/* usp must be word aligned. This also prevents users from
* passing in the value 1 (which is the signal for a special
* return for a kernel thread) */
usp = ALIGN(usp, 4);
/* A zero value for usp means use the current stack */
if (usp == 0)
usp = regs->gr[30];
return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
}
int
sys_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
}
int
copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused, /* in ia64 this is "user_stack_size" */
struct task_struct * p, struct pt_regs * pregs)
{
struct pt_regs * cregs = &(p->thread.regs);
void *stack = task_stack_page(p);
/* We have to use void * instead of a function pointer, because
* function pointers aren't a pointer to the function on 64-bit.
* Make them const so the compiler knows they live in .text */
extern void * const ret_from_kernel_thread;
extern void * const child_return;
#ifdef CONFIG_HPUX
extern void * const hpux_child_return;
#endif
*cregs = *pregs;
/* Set the return value for the child. Note that this is not
actually restored by the syscall exit path, but we put it
here for consistency in case of signals. */
cregs->gr[28] = 0; /* child */
/*
* We need to differentiate between a user fork and a
* kernel fork. We can't use user_mode, because the
* the syscall path doesn't save iaoq. Right now
* We rely on the fact that kernel_thread passes
* in zero for usp.
*/
if (usp == 1) {
/* kernel thread */
cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
/* Must exit via ret_from_kernel_thread in order
* to call schedule_tail()
*/
cregs->kpc = (unsigned long) &ret_from_kernel_thread;
/*
* Copy function and argument to be called from
* ret_from_kernel_thread.
*/
#ifdef CONFIG_64BIT
cregs->gr[27] = pregs->gr[27];
#endif
cregs->gr[26] = pregs->gr[26];
cregs->gr[25] = pregs->gr[25];
} else {
/* user thread */
/*
* Note that the fork wrappers are responsible
* for setting gr[21].
*/
/* Use same stack depth as parent */
cregs->ksp = (unsigned long)stack
+ (pregs->gr[21] & (THREAD_SIZE - 1));
cregs->gr[30] = usp;
if (p->personality == PER_HPUX) {
#ifdef CONFIG_HPUX
cregs->kpc = (unsigned long) &hpux_child_return;
#else
BUG();
#endif
} else {
cregs->kpc = (unsigned long) &child_return;
}
/* Setup thread TLS area from the 4th parameter in clone */
if (clone_flags & CLONE_SETTLS)
cregs->cr27 = pregs->gr[23];
}
return 0;
}
unsigned long thread_saved_pc(struct task_struct *t)
{
return t->thread.regs.kpc;
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(struct pt_regs *regs)
{
int error;
char *filename;
filename = getname((const char __user *) regs->gr[26]);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename, (char __user * __user *) regs->gr[25],
(char __user * __user *) regs->gr[24], regs);
putname(filename);
out:
return error;
}
extern int __execve(const char *filename, char *const argv[],
char *const envp[], struct task_struct *task);
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
return __execve(filename, argv, envp, current);
}
unsigned long
get_wchan(struct task_struct *p)
{
struct unwind_frame_info info;
unsigned long ip;
int count = 0;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
/*
* These bracket the sleeping functions..
*/
unwind_frame_init_from_blocked_task(&info, p);
do {
if (unwind_once(&info) < 0)
return 0;
ip = info.ip;
if (!in_sched_functions(ip))
return ip;
} while (count++ < 16);
return 0;
}
#ifdef CONFIG_64BIT
void *dereference_function_descriptor(void *ptr)
{
Elf64_Fdesc *desc = ptr;
void *p;
if (!probe_kernel_address(&desc->addr, p))
ptr = p;
return ptr;
}
#endif
