mn10300: add the MN10300/AM33 architecture to the kernel

Add architecture support for the MN10300/AM33 CPUs produced by MEI to the
kernel.

This patch also adds board support for the ASB2303 with the ASB2308 daughter
board, and the ASB2305.  The only processor supported is the MN103E010, which
is an AM33v2 core plus on-chip devices.

[akpm@linux-foundation.org: nuke cvs control strings]
Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 297 insertions, 0 deletions

diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c
new file mode 100644
index 000000000000..3b0d579fc15d
--- /dev/null
+++ b/arch/mn10300/kernel/process.c
@@ -0,0 +1,297 @@
+/* MN10300  Process handling code
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#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/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/a.out.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <linux/percpu.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+#include <asm/fpu.h>
+#include <asm/reset-regs.h>
+#include <asm/gdb-stub.h>
+#include "internal.h"
+
+/*
+ * power management idle function, if any..
+ */
+void (*pm_idle)(void);
+EXPORT_SYMBOL(pm_idle);
+
+/*
+ * return saved PC of a blocked thread.
+ */
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+	return ((unsigned long *) tsk->thread.sp)[3];
+}
+
+/*
+ * power off function, if any
+ */
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+/*
+ * we use this if we don't have any better idle routine
+ */
+static void default_idle(void)
+{
+	local_irq_disable();
+	if (!need_resched())
+		safe_halt();
+	else
+		local_irq_enable();
+}
+
+/*
+ * 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)
+{
+	int cpu = smp_processor_id();
+
+	/* endless idle loop with no priority at all */
+	for (;;) {
+		while (!need_resched()) {
+			void (*idle)(void);
+
+			smp_rmb();
+			idle = pm_idle;
+			if (!idle)
+				idle = default_idle;
+
+			irq_stat[cpu].idle_timestamp = jiffies;
+			idle();
+		}
+
+		preempt_enable_no_resched();
+		schedule();
+		preempt_disable();
+	}
+}
+
+void release_segments(struct mm_struct *mm)
+{
+}
+
+void machine_restart(char *cmd)
+{
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+
+#ifdef mn10300_unit_hard_reset
+	mn10300_unit_hard_reset();
+#else
+	mn10300_proc_hard_reset();
+#endif
+}
+
+void machine_halt(void)
+{
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+}
+
+void machine_power_off(void)
+{
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+}
+
+void show_regs(struct pt_regs *regs)
+{
+}
+
+/*
+ * create a kernel thread
+ */
+int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
+{
+	struct pt_regs regs;
+
+	memset(&regs, 0, sizeof(regs));
+
+	regs.a2 = (unsigned long) fn;
+	regs.d2 = (unsigned long) arg;
+	regs.pc = (unsigned long) kernel_thread_helper;
+	local_save_flags(regs.epsw);
+	regs.epsw |= EPSW_IE | EPSW_IM_7;
+
+	/* Ok, create the new process.. */
+	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0,
+		       NULL, NULL);
+}
+
+/*
+ * free current thread data structures etc..
+ */
+void exit_thread(void)
+{
+	exit_fpu();
+}
+
+void flush_thread(void)
+{
+	flush_fpu();
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+}
+
+/*
+ * we do not have to muck with descriptors here, that is
+ * done in switch_mm() as needed.
+ */
+void copy_segments(struct task_struct *p, struct mm_struct *new_mm)
+{
+}
+
+/*
+ * this gets called before we allocate a new thread and copy the current task
+ * into it so that we can store lazy state into memory
+ */
+void prepare_to_copy(struct task_struct *tsk)
+{
+	unlazy_fpu(tsk);
+}
+
+/*
+ * set up the kernel stack for a new thread and copy arch-specific thread
+ * control information
+ */
+int copy_thread(int nr, unsigned long clone_flags,
+		unsigned long c_usp, unsigned long ustk_size,
+		struct task_struct *p, struct pt_regs *kregs)
+{
+	struct pt_regs *c_uregs, *c_kregs, *uregs;
+	unsigned long c_ksp;
+
+	uregs = current->thread.uregs;
+
+	c_ksp = (unsigned long) task_stack_page(p) + THREAD_SIZE;
+
+	/* allocate the userspace exception frame and set it up */
+	c_ksp -= sizeof(struct pt_regs);
+	c_uregs = (struct pt_regs *) c_ksp;
+
+	p->thread.uregs = c_uregs;
+	*c_uregs = *uregs;
+	c_uregs->sp = c_usp;
+	c_uregs->epsw &= ~EPSW_FE; /* my FPU */
+
+	c_ksp -= 12; /* allocate function call ABI slack */
+
+	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
+	if (clone_flags & CLONE_SETTLS)
+		c_uregs->e2 = __frame->d3;
+
+	/* set up the return kernel frame if called from kernel_thread() */
+	c_kregs = c_uregs;
+	if (kregs != uregs) {
+		c_ksp -= sizeof(struct pt_regs);
+		c_kregs = (struct pt_regs *) c_ksp;
+		*c_kregs = *kregs;
+		c_kregs->sp = c_usp;
+		c_kregs->next = c_uregs;
+#ifdef CONFIG_MN10300_CURRENT_IN_E2
+		c_kregs->e2 = (unsigned long) p; /* current */
+#endif
+
+		c_ksp -= 12; /* allocate function call ABI slack */
+	}
+
+	/* set up things up so the scheduler can start the new task */
+	p->thread.__frame = c_kregs;
+	p->thread.a3	= (unsigned long) c_kregs;
+	p->thread.sp	= c_ksp;
+	p->thread.pc	= (unsigned long) ret_from_fork;
+	p->thread.wchan	= (unsigned long) ret_from_fork;
+	p->thread.usp	= c_usp;
+
+	return 0;
+}
+
+/*
+ * clone a process
+ * - tlsptr is retrieved by copy_thread() from __frame->d3
+ */
+asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp,
+			  int __user *parent_tidptr, int __user *child_tidptr,
+			  int __user *tlsptr)
+{
+	return do_fork(clone_flags, newsp ?: __frame->sp, __frame, 0,
+		       parent_tidptr, child_tidptr);
+}
+
+asmlinkage long sys_fork(void)
+{
+	return do_fork(SIGCHLD, __frame->sp, __frame, 0, NULL, NULL);
+}
+
+asmlinkage long sys_vfork(void)
+{
+	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, __frame->sp, __frame,
+		       0, NULL, NULL);
+}
+
+asmlinkage long sys_execve(char __user *name,
+			   char __user * __user *argv,
+			   char __user * __user *envp)
+{
+	char *filename;
+	int error;
+
+	lock_kernel();
+
+	filename = getname(name);
+	error = PTR_ERR(filename);
+	if (!IS_ERR(filename)) {
+		error = do_execve(filename, argv, envp, __frame);
+		if (error == 0)
+			current->ptrace &= ~PT_DTRACE;
+
+		putname(filename);
+	}
+
+	unlock_kernel();
+	return error;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+	return p->thread.wchan;
+}