sh: Split out arch/sh/kernel/process.c for _32 and _64 variants.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 691 insertions, 0 deletions

diff --git a/arch/sh/kernel/process_64.c b/arch/sh/kernel/process_64.c
new file mode 100644
index 00000000000..0761af4d2a4
--- /dev/null
+++ b/arch/sh/kernel/process_64.c
@@ -0,0 +1,691 @@
+/*
+ * 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..
+ */
+#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/proc_fs.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+struct task_struct *last_task_used_math = NULL;
+
+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();
+				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 (*pm_power_off)(void) = machine_power_off;
+EXPORT_SYMBOL(pm_power_off);
+
+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);
+	}
+}
+
+struct task_struct * alloc_task_struct(void)
+{
+	/* Get task descriptor pages */
+	return (struct task_struct *)
+		__get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
+}
+
+void free_task_struct(struct task_struct *p)
+{
+	free_pages((unsigned long) p, get_order(THREAD_SIZE));
+}
+
+/*
+ * 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;
+
+	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);
+
+	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
+		       &regs, 0, NULL, NULL);
+}
+
+/*
+ * 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/sh64/kernel/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) {
+			grab_fpu();
+			fpsave(&tsk->thread.fpu.hard);
+			release_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(int nr, 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) {
+		grab_fpu();
+		fpsave(&current->thread.fpu.hard);
+		release_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;
+
+	lock_kernel();
+	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:
+	unlock_kernel();
+	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)
+
+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);
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+	unsigned long schedule_fp;
+	unsigned long sh64_switch_to_fp;
+	unsigned long schedule_caller_pc;
+	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)) {
+		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;
+}
+
+/* Provide a /proc/asids file that lists out the
+   ASIDs currently associated with the processes.  (If the DM.PC register is
+   examined through the debug link, this shows ASID + PC.  To make use of this,
+   the PID->ASID relationship needs to be known.  This is primarily for
+   debugging.)
+   */
+
+#if defined(CONFIG_SH64_PROC_ASIDS)
+static int
+asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
+{
+	int len=0;
+	struct task_struct *p;
+	read_lock(&tasklist_lock);
+	for_each_process(p) {
+		int pid = p->pid;
+		struct mm_struct *mm;
+		if (!pid) continue;
+		mm = p->mm;
+		if (mm) {
+			unsigned long asid, context;
+			context = mm->context;
+			asid = (context & 0xff);
+			len += sprintf(buf+len, "%5d : %02lx\n", pid, asid);
+		} else {
+			len += sprintf(buf+len, "%5d : (none)\n", pid);
+		}
+	}
+	read_unlock(&tasklist_lock);
+	*eof = 1;
+	return len;
+}
+
+static int __init register_proc_asids(void)
+{
+	create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
+	return 0;
+}
+__initcall(register_proc_asids);
+#endif