process.c

linux-2.6.15.6

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * arch/sh64/kernel/process.c
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003  Paul Mundt
 * Copyright (C) 2003, 2004 Richard Curnow
 *
 * Started from SH3/4 version:
 *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *
 *   In turn started from i386 version:
 *     Copyright (C) 1995  Linus Torvalds
 *
 */

/*
 * This file handles the architecture-dependent parts of process handling..
 */

/* Temporary flags/tests. All to be removed/undefined. BEGIN */
#define IDLE_TRACE
#define VM_SHOW_TABLES
#define VM_TEST_FAULT
#define VM_TEST_RTLBMISS
#define VM_TEST_WTLBMISS

#undef VM_SHOW_TABLES
#undef IDLE_TRACE
/* Temporary flags/tests. All to be removed/undefined. END */

#define __KERNEL_SYSCALLS__
#include <stdarg.h>

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/rwsem.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
#include <linux/unistd.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/init.h>

#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/processor.h>		/* includes also <asm/registers.h> */
#include <asm/mmu_context.h>
#include <asm/elf.h>
#include <asm/page.h>

#include <linux/irq.h>

struct task_struct *last_task_used_math = NULL;

#ifdef IDLE_TRACE
#ifdef VM_SHOW_TABLES
/* For testing */
static void print_PTE(long base)
{
	int i, skip=0;
	long long x, y, *p = (long long *) base;

	for (i=0; i< 512; i++, p++){
		if (*p == 0) {
			if (!skip) {
				skip++;
				printk("(0s) ");
			}
		} else {
			skip=0;
			x = (*p) >> 32;
			y = (*p) & 0xffffffff;
			printk("%08Lx%08Lx ", x, y);
			if (!((i+1)&0x3)) printk("\n");
		}
	}
}

/* For testing */
static void print_DIR(long base)
{
	int i, skip=0;
	long *p = (long *) base;

	for (i=0; i< 512; i++, p++){
		if (*p == 0) {
			if (!skip) {
				skip++;
				printk("(0s) ");
			}
		} else {
			skip=0;
			printk("%08lx ", *p);
			if (!((i+1)&0x7)) printk("\n");
		}
	}
}

/* For testing */
static void print_vmalloc_first_tables(void)
{

#define PRESENT	0x800	/* Bit 11 */

	/*
	 * Do it really dirty by looking at raw addresses,
         * raw offsets, no types. If we used pgtable/pgalloc
	 * macros/definitions we could hide potential bugs.
	 *
	 * Note that pointers are 32-bit for CDC.
	 */
	long pgdt, pmdt, ptet;

	pgdt = (long) &swapper_pg_dir;
	printk("-->PGD (0x%08lx):\n", pgdt);
	print_DIR(pgdt);
	printk("\n");

	/* VMALLOC pool is mapped at 0xc0000000, second (pointer) entry in PGD */
	pgdt += 4;
	pmdt = (long) (* (long *) pgdt);
	if (!(pmdt & PRESENT)) {
		printk("No PMD\n");
		return;
	} else pmdt &= 0xfffff000;

	printk("-->PMD (0x%08lx):\n", pmdt);
	print_DIR(pmdt);
	printk("\n");

	/* Get the pmdt displacement for 0xc0000000 */
	pmdt += 2048;

	/* just look at first two address ranges ... */
        /* ... 0xc0000000 ... */
	ptet = (long) (* (long *) pmdt);
	if (!(ptet & PRESENT)) {
		printk("No PTE0\n");
		return;
	} else ptet &= 0xfffff000;

	printk("-->PTE0 (0x%08lx):\n", ptet);
	print_PTE(ptet);
	printk("\n");

        /* ... 0xc0001000 ... */
	ptet += 4;
	if (!(ptet & PRESENT)) {
		printk("No PTE1\n");
		return;
	} else ptet &= 0xfffff000;
	printk("-->PTE1 (0x%08lx):\n", ptet);
	print_PTE(ptet);
	printk("\n");
}
#else
#define print_vmalloc_first_tables()
#endif	/* VM_SHOW_TABLES */

static void test_VM(void)
{
	void *a, *b, *c;

#ifdef VM_SHOW_TABLES
	printk("Initial PGD/PMD/PTE\n");
#endif
        print_vmalloc_first_tables();

	printk("Allocating 2 bytes\n");
	a = vmalloc(2);
        print_vmalloc_first_tables();

	printk("Allocating 4100 bytes\n");
	b = vmalloc(4100);
        print_vmalloc_first_tables();

	printk("Allocating 20234 bytes\n");
	c = vmalloc(20234);
        print_vmalloc_first_tables();

#ifdef VM_TEST_FAULT
	/* Here you may want to fault ! */

#ifdef VM_TEST_RTLBMISS
	printk("Ready to fault upon read.\n");
	if (* (char *) a) {
		printk("RTLBMISSed on area a !\n");
	}
	printk("RTLBMISSed on area a !\n");
#endif

#ifdef VM_TEST_WTLBMISS
	printk("Ready to fault upon write.\n");
	*((char *) b) = 'L';
	printk("WTLBMISSed on area b !\n");
#endif

#endif	/* VM_TEST_FAULT */

	printk("Deallocating the 4100 byte chunk\n");
	vfree(b);
        print_vmalloc_first_tables();

	printk("Deallocating the 2 byte chunk\n");
	vfree(a);
        print_vmalloc_first_tables();

	printk("Deallocating the last chunk\n");
	vfree(c);
        print_vmalloc_first_tables();
}

extern unsigned long volatile jiffies;
int once = 0;
unsigned long old_jiffies;
int pid = -1, pgid = -1;

void idle_trace(void)
{

	_syscall0(int, getpid)
	_syscall1(int, getpgid, int, pid)

	if (!once) {
        	/* VM allocation/deallocation simple test */
		test_VM();
		pid = getpid();

        	printk("Got all through to Idle !!\n");
        	printk("I'm now going to loop forever ...\n");
        	printk("Any ! below is a timer tick.\n");
		printk("Any . below is a getpgid system call from pid = %d.\n", pid);


        	old_jiffies = jiffies;
		once++;
	}

	if (old_jiffies != jiffies) {
		old_jiffies = jiffies - old_jiffies;
		switch (old_jiffies) {
		case 1:
			printk("!");
			break;
		case 2:
			printk("!!");
			break;
		case 3:
			printk("!!!");
			break;
		case 4:
			printk("!!!!");
			break;
		default:
			printk("(%d!)", (int) old_jiffies);
		}
		old_jiffies = jiffies;
	}
	pgid = getpgid(pid);
	printk(".");
}
#else
#define idle_trace()	do { } while (0)
#endif	/* IDLE_TRACE */

static int hlt_counter = 1;

#define HARD_IDLE_TIMEOUT (HZ / 3)

void disable_hlt(void)
{
	hlt_counter++;
}

void enable_hlt(void)
{
	hlt_counter--;
}

static int __init nohlt_setup(char *__unused)
{
	hlt_counter = 1;
	return 1;
}

static int __init hlt_setup(char *__unused)
{
	hlt_counter = 0;
	return 1;
}

__setup("nohlt", nohlt_setup);
__setup("hlt", hlt_setup);

static inline void hlt(void)
{
	__asm__ __volatile__ ("sleep" : : : "memory");
}

/*
 * The idle loop on a uniprocessor SH..
 */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		if (hlt_counter) {
			while (!need_resched())
				cpu_relax();
		} else {
			local_irq_disable();
			while (!need_resched()) {
				local_irq_enable();
				idle_trace();
				hlt();
				local_irq_disable();
			}
			local_irq_enable();
		}
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}

}

void machine_restart(char * __unused)
{
	extern void phys_stext(void);

	phys_stext();
}

void machine_halt(void)
{
	for (;;);
}

void machine_power_off(void)
{
	extern void enter_deep_standby(void);

	enter_deep_standby();
}

void show_regs(struct pt_regs * regs)
{
	unsigned long long ah, al, bh, bl, ch, cl;

	printk("\n");

	ah = (regs->pc) >> 32;
	al = (regs->pc) & 0xffffffff;
	bh = (regs->regs[18]) >> 32;
	bl = (regs->regs[18]) & 0xffffffff;
	ch = (regs->regs[15]) >> 32;
	cl = (regs->regs[15]) & 0xffffffff;
	printk("PC  : %08Lx%08Lx LINK: %08Lx%08Lx SP  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->sr) >> 32;
	al = (regs->sr) & 0xffffffff;
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bh));
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bl));
	bh = (bh) >> 32;
	bl = (bl) & 0xffffffff;
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (ch));
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (cl));
	ch = (ch) >> 32;
	cl = (cl) & 0xffffffff;
	printk("SR  : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[0]) >> 32;
	al = (regs->regs[0]) & 0xffffffff;
	bh = (regs->regs[1]) >> 32;
	bl = (regs->regs[1]) & 0xffffffff;
	ch = (regs->regs[2]) >> 32;
	cl = (regs->regs[2]) & 0xffffffff;
	printk("R0  : %08Lx%08Lx R1  : %08Lx%08Lx R2  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[3]) >> 32;
	al = (regs->regs[3]) & 0xffffffff;
	bh = (regs->regs[4]) >> 32;
	bl = (regs->regs[4]) & 0xffffffff;
	ch = (regs->regs[5]) >> 32;
	cl = (regs->regs[5]) & 0xffffffff;
	printk("R3  : %08Lx%08Lx R4  : %08Lx%08Lx R5  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[6]) >> 32;
	al = (regs->regs[6]) & 0xffffffff;
	bh = (regs->regs[7]) >> 32;
	bl = (regs->regs[7]) & 0xffffffff;
	ch = (regs->regs[8]) >> 32;
	cl = (regs->regs[8]) & 0xffffffff;
	printk("R6  : %08Lx%08Lx R7  : %08Lx%08Lx R8  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[9]) >> 32;
	al = (regs->regs[9]) & 0xffffffff;
	bh = (regs->regs[10]) >> 32;
	bl = (regs->regs[10]) & 0xffffffff;
	ch = (regs->regs[11]) >> 32;
	cl = (regs->regs[11]) & 0xffffffff;
	printk("R9  : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[12]) >> 32;
	al = (regs->regs[12]) & 0xffffffff;
	bh = (regs->regs[13]) >> 32;
	bl = (regs->regs[13]) & 0xffffffff;
	ch = (regs->regs[14]) >> 32;
	cl = (regs->regs[14]) & 0xffffffff;
	printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[16]) >> 32;
	al = (regs->regs[16]) & 0xffffffff;
	bh = (regs->regs[17]) >> 32;
	bl = (regs->regs[17]) & 0xffffffff;
	ch = (regs->regs[19]) >> 32;
	cl = (regs->regs[19]) & 0xffffffff;
	printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[20]) >> 32;
	al = (regs->regs[20]) & 0xffffffff;
	bh = (regs->regs[21]) >> 32;
	bl = (regs->regs[21]) & 0xffffffff;
	ch = (regs->regs[22]) >> 32;
	cl = (regs->regs[22]) & 0xffffffff;
	printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[23]) >> 32;
	al = (regs->regs[23]) & 0xffffffff;
	bh = (regs->regs[24]) >> 32;
	bl = (regs->regs[24]) & 0xffffffff;
	ch = (regs->regs[25]) >> 32;
	cl = (regs->regs[25]) & 0xffffffff;
	printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[26]) >> 32;
	al = (regs->regs[26]) & 0xffffffff;
	bh = (regs->regs[27]) >> 32;
	bl = (regs->regs[27]) & 0xffffffff;
	ch = (regs->regs[28]) >> 32;
	cl = (regs->regs[28]) & 0xffffffff;
	printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[29]) >> 32;
	al = (regs->regs[29]) & 0xffffffff;
	bh = (regs->regs[30]) >> 32;
	bl = (regs->regs[30]) & 0xffffffff;
	ch = (regs->regs[31]) >> 32;
	cl = (regs->regs[31]) & 0xffffffff;
	printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[32]) >> 32;
	al = (regs->regs[32]) & 0xffffffff;
	bh = (regs->regs[33]) >> 32;