arch/sh/kernel/process_64.c - maze/linux - Git at Google

 /*
  * arch/sh/kernel/process_64.c
  *
  * This file handles the architecture-dependent parts of process handling..
  *
  * Copyright (C) 2000, 2001  Paolo Alberelli
  * Copyright (C) 2003 - 2007  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 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.
  */
 #include <linux/mm.h>
 #include <linux/fs.h>
 #include <linux/ptrace.h>
 #include <linux/reboot.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/io.h>
 #include <asm/syscalls.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/mmu_context.h>
 #include <asm/fpu.h>

 struct task_struct *last_task_used_math = NULL;

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

 	phys_stext();
 }

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

 void machine_power_off(void)
 {
 	__asm__ __volatile__ (
 		"sleep\n\t"
 		"synci\n\t"
 		"nop;nop;nop;nop\n\t"
 	);

 	panic("Unexpected wakeup!\n");
 }

 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;
 	bl = (regs->regs[33]) & 0xffffffff;
 	ch = (regs->regs[34]) >> 32;
 	cl = (regs->regs[34]) & 0xffffffff;
 	printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[35]) >> 32;
 	al = (regs->regs[35]) & 0xffffffff;
 	bh = (regs->regs[36]) >> 32;
 	bl = (regs->regs[36]) & 0xffffffff;
 	ch = (regs->regs[37]) >> 32;
 	cl = (regs->regs[37]) & 0xffffffff;
 	printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[38]) >> 32;
 	al = (regs->regs[38]) & 0xffffffff;
 	bh = (regs->regs[39]) >> 32;
 	bl = (regs->regs[39]) & 0xffffffff;
 	ch = (regs->regs[40]) >> 32;
 	cl = (regs->regs[40]) & 0xffffffff;
 	printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[41]) >> 32;
 	al = (regs->regs[41]) & 0xffffffff;
 	bh = (regs->regs[42]) >> 32;
 	bl = (regs->regs[42]) & 0xffffffff;
 	ch = (regs->regs[43]) >> 32;
 	cl = (regs->regs[43]) & 0xffffffff;
 	printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[44]) >> 32;
 	al = (regs->regs[44]) & 0xffffffff;
 	bh = (regs->regs[45]) >> 32;
 	bl = (regs->regs[45]) & 0xffffffff;
 	ch = (regs->regs[46]) >> 32;
 	cl = (regs->regs[46]) & 0xffffffff;
 	printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[47]) >> 32;
 	al = (regs->regs[47]) & 0xffffffff;
 	bh = (regs->regs[48]) >> 32;
 	bl = (regs->regs[48]) & 0xffffffff;
 	ch = (regs->regs[49]) >> 32;
 	cl = (regs->regs[49]) & 0xffffffff;
 	printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[50]) >> 32;
 	al = (regs->regs[50]) & 0xffffffff;
 	bh = (regs->regs[51]) >> 32;
 	bl = (regs->regs[51]) & 0xffffffff;
 	ch = (regs->regs[52]) >> 32;
 	cl = (regs->regs[52]) & 0xffffffff;
 	printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[53]) >> 32;
 	al = (regs->regs[53]) & 0xffffffff;
 	bh = (regs->regs[54]) >> 32;
 	bl = (regs->regs[54]) & 0xffffffff;
 	ch = (regs->regs[55]) >> 32;
 	cl = (regs->regs[55]) & 0xffffffff;
 	printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[56]) >> 32;
 	al = (regs->regs[56]) & 0xffffffff;
 	bh = (regs->regs[57]) >> 32;
 	bl = (regs->regs[57]) & 0xffffffff;
 	ch = (regs->regs[58]) >> 32;
 	cl = (regs->regs[58]) & 0xffffffff;
 	printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[59]) >> 32;
 	al = (regs->regs[59]) & 0xffffffff;
 	bh = (regs->regs[60]) >> 32;
 	bl = (regs->regs[60]) & 0xffffffff;
 	ch = (regs->regs[61]) >> 32;
 	cl = (regs->regs[61]) & 0xffffffff;
 	printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->regs[62]) >> 32;
 	al = (regs->regs[62]) & 0xffffffff;
 	bh = (regs->tregs[0]) >> 32;
 	bl = (regs->tregs[0]) & 0xffffffff;
 	ch = (regs->tregs[1]) >> 32;
 	cl = (regs->tregs[1]) & 0xffffffff;
 	printk("R62 : %08Lx%08Lx T0  : %08Lx%08Lx T1  : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->tregs[2]) >> 32;
 	al = (regs->tregs[2]) & 0xffffffff;
 	bh = (regs->tregs[3]) >> 32;
 	bl = (regs->tregs[3]) & 0xffffffff;
 	ch = (regs->tregs[4]) >> 32;
 	cl = (regs->tregs[4]) & 0xffffffff;
 	printk("T2  : %08Lx%08Lx T3  : %08Lx%08Lx T4  : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	ah = (regs->tregs[5]) >> 32;
 	al = (regs->tregs[5]) & 0xffffffff;
 	bh = (regs->tregs[6]) >> 32;
 	bl = (regs->tregs[6]) & 0xffffffff;
 	ch = (regs->tregs[7]) >> 32;
 	cl = (regs->tregs[7]) & 0xffffffff;
 	printk("T5  : %08Lx%08Lx T6  : %08Lx%08Lx T7  : %08Lx%08Lx\n",
 	       ah, al, bh, bl, ch, cl);

 	/*
 	 * If we're in kernel mode, dump the stack too..
 	 */
 	if (!user_mode(regs)) {
 		void show_stack(struct task_struct *tsk, unsigned long *sp);
 		unsigned long sp = regs->regs[15] & 0xffffffff;
 		struct task_struct *tsk = get_current();

 		tsk->thread.kregs = regs;

 		show_stack(tsk, (unsigned long *)sp);
 	}
 }

 /*
  * Create a kernel thread
  */
 ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
 {
 	do_exit(fn(arg));
 }

 /*
  * This is the mechanism for creating a new kernel thread.
  *
  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
  * who haven't done an "execve()") should use this: it will work within
  * a system call from a "real" process, but the process memory space will
  * not be freed until both the parent and the child have exited.
  */
 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 {
 	struct pt_regs regs;
 	int pid;

 	memset(&regs, 0, sizeof(regs));
 	regs.regs[2] = (unsigned long)arg;
 	regs.regs[3] = (unsigned long)fn;

 	regs.pc = (unsigned long)kernel_thread_helper;
 	regs.sr = (1 << 30);

 	/* Ok, create the new process.. */
 	pid = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
 		      &regs, 0, NULL, NULL);

 	trace_mark(kernel_arch_kthread_create, "pid %d fn %p", pid, fn);

 	return pid;
 }

 /*
  * Free current thread data structures etc..
  */
 void exit_thread(void)
 {
 	/*
 	 * See arch/sparc/kernel/process.c for the precedent for doing
 	 * this -- RPC.
 	 *
 	 * The SH-5 FPU save/restore approach relies on
 	 * last_task_used_math pointing to a live task_struct.  When
 	 * another task tries to use the FPU for the 1st time, the FPUDIS
 	 * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
 	 * existing FPU state to the FP regs field within
 	 * last_task_used_math before re-loading the new task's FPU state
 	 * (or initialising it if the FPU has been used before).  So if
 	 * last_task_used_math is stale, and its page has already been
 	 * re-allocated for another use, the consequences are rather
 	 * grim. Unless we null it here, there is no other path through
 	 * which it would get safely nulled.
 	 */
 #ifdef CONFIG_SH_FPU
 	if (last_task_used_math == current) {
 		last_task_used_math = NULL;
 	}
 #endif
 }

 void flush_thread(void)
 {

 	/* Called by fs/exec.c (flush_old_exec) to remove traces of a
 	 * previously running executable. */
 #ifdef CONFIG_SH_FPU
 	if (last_task_used_math == current) {
 		last_task_used_math = NULL;
 	}
 	/* Force FPU state to be reinitialised after exec */
 	clear_used_math();
 #endif

 	/* if we are a kernel thread, about to change to user thread,
          * update kreg
          */
 	if(current->thread.kregs==&fake_swapper_regs) {
           current->thread.kregs =
              ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
 	  current->thread.uregs = current->thread.kregs;
 	}
 }

 void release_thread(struct task_struct *dead_task)
 {
 	/* do nothing */
 }

 /* Fill in the fpu structure for a core dump.. */
 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
 {
 #ifdef CONFIG_SH_FPU
 	int fpvalid;
 	struct task_struct *tsk = current;

 	fpvalid = !!tsk_used_math(tsk);
 	if (fpvalid) {
 		if (current == last_task_used_math) {
 			enable_fpu();
 			save_fpu(tsk, regs);
 			disable_fpu();
 			last_task_used_math = 0;
 			regs->sr |= SR_FD;
 		}

 		memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
 	}

 	return fpvalid;
 #else
 	return 0; /* Task didn't use the fpu at all. */
 #endif
 }

 asmlinkage void ret_from_fork(void);

 int copy_thread(unsigned long clone_flags, unsigned long usp,
 		unsigned long unused,
 		struct task_struct *p, struct pt_regs *regs)
 {
 	struct pt_regs *childregs;
 	unsigned long long se;			/* Sign extension */

 #ifdef CONFIG_SH_FPU
 	if(last_task_used_math == current) {
 		enable_fpu();
 		save_fpu(current, regs);
 		disable_fpu();
 		last_task_used_math = NULL;
 		regs->sr |= SR_FD;
 	}
 #endif
 	/* Copy from sh version */
 	childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;

 	*childregs = *regs;

 	if (user_mode(regs)) {
 		childregs->regs[15] = usp;
 		p->thread.uregs = childregs;
 	} else {
 		childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
 	}

 	childregs->regs[9] = 0; /* Set return value for child */
 	childregs->sr |= SR_FD; /* Invalidate FPU flag */

 	p->thread.sp = (unsigned long) childregs;
 	p->thread.pc = (unsigned long) ret_from_fork;

 	/*
 	 * Sign extend the edited stack.
          * Note that thread.pc and thread.pc will stay
 	 * 32-bit wide and context switch must take care
 	 * of NEFF sign extension.
 	 */

 	se = childregs->regs[15];
 	se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
 	childregs->regs[15] = se;

 	return 0;
 }

 asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
 			unsigned long r4, unsigned long r5,
 			unsigned long r6, unsigned long r7,
 			struct pt_regs *pregs)
 {
 	return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 }

 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
 			 unsigned long r4, unsigned long r5,
 			 unsigned long r6, unsigned long r7,
 			 struct pt_regs *pregs)
 {
 	if (!newsp)
 		newsp = pregs->regs[15];
 	return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
 }

 /*
  * This is trivial, and on the face of it looks like it
  * could equally well be done in user mode.
  *
  * Not so, for quite unobvious reasons - register pressure.
  * In user mode vfork() cannot have a stack frame, and if
  * done by calling the "clone()" system call directly, you
  * do not have enough call-clobbered registers to hold all
  * the information you need.
  */
 asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
 			 unsigned long r4, unsigned long r5,
 			 unsigned long r6, unsigned long r7,
 			 struct pt_regs *pregs)
 {
 	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
 }

 /*
  * sys_execve() executes a new program.
  */
 asmlinkage int sys_execve(char *ufilename, char **uargv,
 			  char **uenvp, unsigned long r5,
 			  unsigned long r6, unsigned long r7,
 			  struct pt_regs *pregs)
 {
 	int error;
 	char *filename;

 	filename = getname((char __user *)ufilename);
 	error = PTR_ERR(filename);
 	if (IS_ERR(filename))
 		goto out;

 	error = do_execve(filename,
 			  (char __user * __user *)uargv,
 			  (char __user * __user *)uenvp,
 			  pregs);
 	if (error == 0) {
 		task_lock(current);
 		current->ptrace &= ~PT_DTRACE;
 		task_unlock(current);
 	}
 	putname(filename);
 out:
 	return error;
 }

 /*
  * These bracket the sleeping functions..
  */
 extern void interruptible_sleep_on(wait_queue_head_t *q);

 #define mid_sched	((unsigned long) interruptible_sleep_on)

 #ifdef CONFIG_FRAME_POINTER
 static int in_sh64_switch_to(unsigned long pc)
 {
 	extern char __sh64_switch_to_end;
 	/* For a sleeping task, the PC is somewhere in the middle of the function,
 	   so we don't have to worry about masking the LSB off */
 	return (pc >= (unsigned long) sh64_switch_to) &&
 	       (pc < (unsigned long) &__sh64_switch_to_end);
 }
 #endif

 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long pc;

 	if (!p || p == current || p->state == TASK_RUNNING)
 		return 0;

 	/*
 	 * The same comment as on the Alpha applies here, too ...
 	 */
 	pc = thread_saved_pc(p);

 #ifdef CONFIG_FRAME_POINTER
 	if (in_sh64_switch_to(pc)) {
 		unsigned long schedule_fp;
 		unsigned long sh64_switch_to_fp;
 		unsigned long schedule_caller_pc;

 		sh64_switch_to_fp = (long) p->thread.sp;
 		/* r14 is saved at offset 4 in the sh64_switch_to frame */
 		schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);

 		/* and the caller of 'schedule' is (currently!) saved at offset 24
 		   in the frame of schedule (from disasm) */
 		schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
 		return schedule_caller_pc;
 	}
 #endif
 	return pc;
 }
	/*
	* arch/sh/kernel/process_64.c
	*
	* This file handles the architecture-dependent parts of process handling..
	*
	* Copyright (C) 2000, 2001 Paolo Alberelli
	* Copyright (C) 2003 - 2007 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 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.
	*/
	#include <linux/mm.h>
	#include <linux/fs.h>
	#include <linux/ptrace.h>
	#include <linux/reboot.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/io.h>
	#include <asm/syscalls.h>
	#include <asm/uaccess.h>
	#include <asm/pgtable.h>
	#include <asm/mmu_context.h>
	#include <asm/fpu.h>

	struct task_struct *last_task_used_math = NULL;

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

	phys_stext();
	}

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

	void machine_power_off(void)
	{
	__asm__ __volatile__ (
	"sleep\n\t"
	"synci\n\t"
	"nop;nop;nop;nop\n\t"
	);

	panic("Unexpected wakeup!\n");
	}

	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;
	bl = (regs->regs[33]) & 0xffffffff;
	ch = (regs->regs[34]) >> 32;
	cl = (regs->regs[34]) & 0xffffffff;
	printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[35]) >> 32;
	al = (regs->regs[35]) & 0xffffffff;
	bh = (regs->regs[36]) >> 32;
	bl = (regs->regs[36]) & 0xffffffff;
	ch = (regs->regs[37]) >> 32;
	cl = (regs->regs[37]) & 0xffffffff;
	printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[38]) >> 32;
	al = (regs->regs[38]) & 0xffffffff;
	bh = (regs->regs[39]) >> 32;
	bl = (regs->regs[39]) & 0xffffffff;
	ch = (regs->regs[40]) >> 32;
	cl = (regs->regs[40]) & 0xffffffff;
	printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[41]) >> 32;
	al = (regs->regs[41]) & 0xffffffff;
	bh = (regs->regs[42]) >> 32;
	bl = (regs->regs[42]) & 0xffffffff;
	ch = (regs->regs[43]) >> 32;
	cl = (regs->regs[43]) & 0xffffffff;
	printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[44]) >> 32;
	al = (regs->regs[44]) & 0xffffffff;
	bh = (regs->regs[45]) >> 32;
	bl = (regs->regs[45]) & 0xffffffff;
	ch = (regs->regs[46]) >> 32;
	cl = (regs->regs[46]) & 0xffffffff;
	printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[47]) >> 32;
	al = (regs->regs[47]) & 0xffffffff;
	bh = (regs->regs[48]) >> 32;
	bl = (regs->regs[48]) & 0xffffffff;
	ch = (regs->regs[49]) >> 32;
	cl = (regs->regs[49]) & 0xffffffff;
	printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[50]) >> 32;
	al = (regs->regs[50]) & 0xffffffff;
	bh = (regs->regs[51]) >> 32;
	bl = (regs->regs[51]) & 0xffffffff;
	ch = (regs->regs[52]) >> 32;
	cl = (regs->regs[52]) & 0xffffffff;
	printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[53]) >> 32;
	al = (regs->regs[53]) & 0xffffffff;
	bh = (regs->regs[54]) >> 32;
	bl = (regs->regs[54]) & 0xffffffff;
	ch = (regs->regs[55]) >> 32;
	cl = (regs->regs[55]) & 0xffffffff;
	printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[56]) >> 32;
	al = (regs->regs[56]) & 0xffffffff;
	bh = (regs->regs[57]) >> 32;
	bl = (regs->regs[57]) & 0xffffffff;
	ch = (regs->regs[58]) >> 32;
	cl = (regs->regs[58]) & 0xffffffff;
	printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[59]) >> 32;
	al = (regs->regs[59]) & 0xffffffff;
	bh = (regs->regs[60]) >> 32;
	bl = (regs->regs[60]) & 0xffffffff;
	ch = (regs->regs[61]) >> 32;
	cl = (regs->regs[61]) & 0xffffffff;
	printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->regs[62]) >> 32;
	al = (regs->regs[62]) & 0xffffffff;
	bh = (regs->tregs[0]) >> 32;
	bl = (regs->tregs[0]) & 0xffffffff;
	ch = (regs->tregs[1]) >> 32;
	cl = (regs->tregs[1]) & 0xffffffff;
	printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[2]) >> 32;
	al = (regs->tregs[2]) & 0xffffffff;
	bh = (regs->tregs[3]) >> 32;
	bl = (regs->tregs[3]) & 0xffffffff;
	ch = (regs->tregs[4]) >> 32;
	cl = (regs->tregs[4]) & 0xffffffff;
	printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[5]) >> 32;
	al = (regs->tregs[5]) & 0xffffffff;
	bh = (regs->tregs[6]) >> 32;
	bl = (regs->tregs[6]) & 0xffffffff;
	ch = (regs->tregs[7]) >> 32;
	cl = (regs->tregs[7]) & 0xffffffff;
	printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n",
	ah, al, bh, bl, ch, cl);

	/*
	* If we're in kernel mode, dump the stack too..
	*/
	if (!user_mode(regs)) {
	void show_stack(struct task_struct tsk, unsigned long sp);
	unsigned long sp = regs->regs[15] & 0xffffffff;
	struct task_struct *tsk = get_current();

	tsk->thread.kregs = regs;

	show_stack(tsk, (unsigned long *)sp);
	}
	}

	/*
	* Create a kernel thread
	*/
	ATTRIB_NORET void kernel_thread_helper(void arg, int (fn)(void *))
	{
	do_exit(fn(arg));
	}

	/*
	* This is the mechanism for creating a new kernel thread.
	*
	* NOTE! Only a kernel-only process(ie the swapper or direct descendants
	* who haven't done an "execve()") should use this: it will work within
	* a system call from a "real" process, but the process memory space will
	* not be freed until both the parent and the child have exited.
	*/
	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	{
	struct pt_regs regs;
	int pid;

	memset(&regs, 0, sizeof(regs));
	regs.regs[2] = (unsigned long)arg;
	regs.regs[3] = (unsigned long)fn;

	regs.pc = (unsigned long)kernel_thread_helper;
	regs.sr = (1 << 30);

	/* Ok, create the new process.. */
	pid = do_fork(flags \| CLONE_VM \| CLONE_UNTRACED, 0,
	&regs, 0, NULL, NULL);

	trace_mark(kernel_arch_kthread_create, "pid %d fn %p", pid, fn);

	return pid;
	}

	/*
	* Free current thread data structures etc..
	*/
	void exit_thread(void)
	{
	/*
	* See arch/sparc/kernel/process.c for the precedent for doing
	* this -- RPC.
	*
	* The SH-5 FPU save/restore approach relies on
	* last_task_used_math pointing to a live task_struct. When
	* another task tries to use the FPU for the 1st time, the FPUDIS
	* trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
	* existing FPU state to the FP regs field within
	* last_task_used_math before re-loading the new task's FPU state
	* (or initialising it if the FPU has been used before). So if
	* last_task_used_math is stale, and its page has already been
	* re-allocated for another use, the consequences are rather
	* grim. Unless we null it here, there is no other path through
	* which it would get safely nulled.
	*/
	#ifdef CONFIG_SH_FPU
	if (last_task_used_math == current) {
	last_task_used_math = NULL;
	}
	#endif
	}

	void flush_thread(void)
	{

	/* Called by fs/exec.c (flush_old_exec) to remove traces of a
	* previously running executable. */
	#ifdef CONFIG_SH_FPU
	if (last_task_used_math == current) {
	last_task_used_math = NULL;
	}
	/* Force FPU state to be reinitialised after exec */
	clear_used_math();
	#endif

	/* if we are a kernel thread, about to change to user thread,
	* update kreg
	*/
	if(current->thread.kregs==&fake_swapper_regs) {
	current->thread.kregs =
	((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
	current->thread.uregs = current->thread.kregs;
	}
	}

	void release_thread(struct task_struct *dead_task)
	{
	/* do nothing */
	}

	/* Fill in the fpu structure for a core dump.. */
	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	{
	#ifdef CONFIG_SH_FPU
	int fpvalid;
	struct task_struct *tsk = current;

	fpvalid = !!tsk_used_math(tsk);
	if (fpvalid) {
	if (current == last_task_used_math) {
	enable_fpu();
	save_fpu(tsk, regs);
	disable_fpu();
	last_task_used_math = 0;
	regs->sr \|= SR_FD;
	}

	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	}

	return fpvalid;
	#else
	return 0; /* Task didn't use the fpu at all. */
	#endif
	}

	asmlinkage void ret_from_fork(void);

	int copy_thread(unsigned long clone_flags, unsigned long usp,
	unsigned long unused,
	struct task_struct p, struct pt_regs regs)
	{
	struct pt_regs *childregs;
	unsigned long long se; /* Sign extension */

	#ifdef CONFIG_SH_FPU
	if(last_task_used_math == current) {
	enable_fpu();
	save_fpu(current, regs);
	disable_fpu();
	last_task_used_math = NULL;
	regs->sr \|= SR_FD;
	}
	#endif
	/* Copy from sh version */
	childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;

	childregs = regs;

	if (user_mode(regs)) {
	childregs->regs[15] = usp;
	p->thread.uregs = childregs;
	} else {
	childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
	}

	childregs->regs[9] = 0; /* Set return value for child */
	childregs->sr \|= SR_FD; /* Invalidate FPU flag */

	p->thread.sp = (unsigned long) childregs;
	p->thread.pc = (unsigned long) ret_from_fork;

	/*
	* Sign extend the edited stack.
	* Note that thread.pc and thread.pc will stay
	* 32-bit wide and context switch must take care
	* of NEFF sign extension.
	*/

	se = childregs->regs[15];
	se = (se & NEFF_SIGN) ? (se \| NEFF_MASK) : se;
	childregs->regs[15] = se;

	return 0;
	}

	asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
	unsigned long r4, unsigned long r5,
	unsigned long r6, unsigned long r7,
	struct pt_regs *pregs)
	{
	return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
	}

	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	unsigned long r4, unsigned long r5,
	unsigned long r6, unsigned long r7,
	struct pt_regs *pregs)
	{
	if (!newsp)
	newsp = pregs->regs[15];
	return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
	}

	/*
	* This is trivial, and on the face of it looks like it
	* could equally well be done in user mode.
	*
	* Not so, for quite unobvious reasons - register pressure.
	* In user mode vfork() cannot have a stack frame, and if
	* done by calling the "clone()" system call directly, you
	* do not have enough call-clobbered registers to hold all
	* the information you need.
	*/
	asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
	unsigned long r4, unsigned long r5,
	unsigned long r6, unsigned long r7,
	struct pt_regs *pregs)
	{
	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
	}

	/*
	* sys_execve() executes a new program.
	*/
	asmlinkage int sys_execve(char ufilename, char *uargv,
	char **uenvp, unsigned long r5,
	unsigned long r6, unsigned long r7,
	struct pt_regs *pregs)
	{
	int error;
	char *filename;

	filename = getname((char __user *)ufilename);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
	goto out;

	error = do_execve(filename,
	(char __user * __user *)uargv,
	(char __user * __user *)uenvp,
	pregs);
	if (error == 0) {
	task_lock(current);
	current->ptrace &= ~PT_DTRACE;
	task_unlock(current);
	}
	putname(filename);
	out:
	return error;
	}

	/*
	* These bracket the sleeping functions..
	*/
	extern void interruptible_sleep_on(wait_queue_head_t *q);

	#define mid_sched ((unsigned long) interruptible_sleep_on)

	#ifdef CONFIG_FRAME_POINTER
	static int in_sh64_switch_to(unsigned long pc)
	{
	extern char __sh64_switch_to_end;
	/* For a sleeping task, the PC is somewhere in the middle of the function,
	so we don't have to worry about masking the LSB off */
	return (pc >= (unsigned long) sh64_switch_to) &&
	(pc < (unsigned long) &__sh64_switch_to_end);
	}
	#endif

	unsigned long get_wchan(struct task_struct *p)
	{
	unsigned long pc;

	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	return 0;

	/*
	* The same comment as on the Alpha applies here, too ...
	*/
	pc = thread_saved_pc(p);

	#ifdef CONFIG_FRAME_POINTER
	if (in_sh64_switch_to(pc)) {
	unsigned long schedule_fp;
	unsigned long sh64_switch_to_fp;
	unsigned long schedule_caller_pc;

	sh64_switch_to_fp = (long) p->thread.sp;
	/* r14 is saved at offset 4 in the sh64_switch_to frame */
	schedule_fp = (unsigned long ) (long)(sh64_switch_to_fp + 4);

	/* and the caller of 'schedule' is (currently!) saved at offset 24
	in the frame of schedule (from disasm) */
	schedule_caller_pc = (unsigned long ) (long)(schedule_fp + 24);
	return schedule_caller_pc;
	}
	#endif
	return pc;
	}