1 files changed, 388 insertions, 0 deletions
diff --git a/arch/frv/kernel/process.c b/arch/frv/kernel/process.c
new file mode 100644
index 0000000..3001b82
--- /dev/null
+++ b/arch/frv/kernel/process.c
@@ -0,0 +1,388 @@
+/* process.c: FRV specific parts of process handling
+ *
+ * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/m68k/kernel/process.c
+ *
+ * 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.
+ */
+
+#include <linux/config.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/elf.h>
+#include <linux/reboot.h>
+#include <linux/interrupt.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/setup.h>
+#include <asm/pgtable.h>
+#include <asm/gdb-stub.h>
+#include <asm/mb-regs.h>
+
+#include "local.h"
+
+asmlinkage void ret_from_fork(void);
+
+#include <asm/pgalloc.h>
+
+struct task_struct *alloc_task_struct(void)
+{
+	struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
+	if (p)
+		atomic_set((atomic_t *)(p+1), 1);
+	return p;
+}
+
+void free_task_struct(struct task_struct *p)
+{
+	if (atomic_dec_and_test((atomic_t *)(p+1)))
+		kfree(p);
+}
+
+static void core_sleep_idle(void)
+{
+#ifdef LED_DEBUG_SLEEP
+	/* Show that we're sleeping... */
+	__set_LEDS(0x55aa);
+#endif
+	frv_cpu_core_sleep();
+#ifdef LED_DEBUG_SLEEP
+	/* ... and that we woke up */
+	__set_LEDS(0);
+#endif
+	mb();
+}
+
+void (*idle)(void) = core_sleep_idle;
+
+/*
+ * 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)
+{
+	/* endless idle loop with no priority at all */
+	while (1) {
+		while (!need_resched()) {
+			irq_stat[smp_processor_id()].idle_timestamp = jiffies;
+
+			if (!frv_dma_inprogress && idle)
+				idle();
+		}
+
+		schedule();
+	}
+}
+
+void machine_restart(char * __unused)
+{
+	unsigned long reset_addr;
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+
+	if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
+		reset_addr = 0xfefff500;
+	else
+		reset_addr = 0xfeff0500;
+
+	/* Software reset. */
+	asm volatile("      dcef @(gr0,gr0),1 ! membar !"
+		     "      sti     %1,@(%0,0) !"
+		     "      nop ! nop ! nop ! nop ! nop ! "
+		     "      nop ! nop ! nop ! nop ! nop ! "
+		     "      nop ! nop ! nop ! nop ! nop ! "
+		     "      nop ! nop ! nop ! nop ! nop ! "
+		     : : "r" (reset_addr), "r" (1) );
+
+	for (;;)
+		;
+}
+
+void machine_halt(void)
+{
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+
+	for (;;);
+}
+
+void machine_power_off(void)
+{
+#ifdef CONFIG_GDBSTUB
+	gdbstub_exit(0);
+#endif
+
+	for (;;);
+}
+
+void flush_thread(void)
+{
+#if 0 //ndef NO_FPU
+	unsigned long zero = 0;
+#endif
+	set_fs(USER_DS);
+}
+
+inline unsigned long user_stack(const struct pt_regs *regs)
+{
+	while (regs->next_frame)
+		regs = regs->next_frame;
+	return user_mode(regs) ? regs->sp : 0;
+}
+
+asmlinkage int sys_fork(void)
+{
+#ifndef CONFIG_MMU
+	/* fork almost works, enough to trick you into looking elsewhere:-( */
+	return -EINVAL;
+#else
+	return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
+#endif
+}
+
+asmlinkage int sys_vfork(void)
+{
+	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
+		       NULL, NULL);
+}
+
+/*****************************************************************************/
+/*
+ * clone a process
+ * - tlsptr is retrieved by copy_thread()
+ */
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+			 int __user *parent_tidptr, int __user *child_tidptr,
+			 int __user *tlsptr)
+{
+	if (!newsp)
+		newsp = user_stack(__frame);
+	return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
+} /* end sys_clone() */
+
+/*****************************************************************************/
+/*
+ * This gets called before we allocate a new thread and copy
+ * the current task into it.
+ */
+void prepare_to_copy(struct task_struct *tsk)
+{
+	//unlazy_fpu(tsk);
+} /* end prepare_to_copy() */
+
+/*****************************************************************************/
+/*
+ * set up the kernel stack and exception frames for a new process
+ */
+int copy_thread(int nr, unsigned long clone_flags,
+		unsigned long usp, unsigned long topstk,
+		struct task_struct *p, struct pt_regs *regs)
+{
+	struct pt_regs *childregs0, *childregs, *regs0;
+
+	regs0 = __kernel_frame0_ptr;
+	childregs0 = (struct pt_regs *)
+		((unsigned long) p->thread_info + THREAD_SIZE - USER_CONTEXT_SIZE);
+	childregs = childregs0;
+
+	/* set up the userspace frame (the only place that the USP is stored) */
+	*childregs0 = *regs0;
+
+	childregs0->gr8		= 0;
+	childregs0->sp		= usp;
+	childregs0->next_frame	= NULL;
+
+	/* set up the return kernel frame if called from kernel_thread() */
+	if (regs != regs0) {
+		childregs--;
+		*childregs = *regs;
+		childregs->sp = (unsigned long) childregs0;
+		childregs->next_frame = childregs0;
+		childregs->gr15 = (unsigned long) p->thread_info;
+		childregs->gr29 = (unsigned long) p;
+	}
+
+	p->set_child_tid = p->clear_child_tid = NULL;
+
+	p->thread.frame	 = childregs;
+	p->thread.curr	 = p;
+	p->thread.sp	 = (unsigned long) childregs;
+	p->thread.fp	 = 0;
+	p->thread.lr	 = 0;
+	p->thread.pc	 = (unsigned long) ret_from_fork;
+	p->thread.frame0 = childregs0;
+
+	/* the new TLS pointer is passed in as arg #5 to sys_clone() */
+	if (clone_flags & CLONE_SETTLS)
+		childregs->gr29 = childregs->gr12;
+
+	save_user_regs(p->thread.user);
+
+	return 0;
+} /* end copy_thread() */
+
+/*
+ * fill in the user structure for a core dump..
+ */
+void dump_thread(struct pt_regs *regs, struct user *dump)
+{
+#if 0
+	/* changed the size calculations - should hopefully work better. lbt */
+	dump->magic = CMAGIC;
+	dump->start_code = 0;
+	dump->start_stack = user_stack(regs) & ~(PAGE_SIZE - 1);
+	dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
+	dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
+	dump->u_dsize -= dump->u_tsize;
+	dump->u_ssize = 0;
+
+	if (dump->start_stack < TASK_SIZE)
+		dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
+
+	dump->regs = *(struct user_context *) regs;
+#endif
+}
+
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(char *name, char **argv, char **envp)
+{
+	int error;
+	char * filename;
+
+	lock_kernel();
+	filename = getname(name);
+	error = PTR_ERR(filename);
+	if (IS_ERR(filename))
+		goto out;
+	error = do_execve(filename, argv, envp, __frame);
+	putname(filename);
+ out:
+	unlock_kernel();
+	return error;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+	struct pt_regs *regs0;
+	unsigned long fp, pc;
+	unsigned long stack_limit;
+	int count = 0;
+	if (!p || p == current || p->state == TASK_RUNNING)
+		return 0;
+
+	stack_limit = (unsigned long) (p + 1);
+	fp = p->thread.fp;
+	regs0 = p->thread.frame0;
+
+	do {
+		if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
+			return 0;
+
+		pc = ((unsigned long *) fp)[2];
+
+		/* FIXME: This depends on the order of these functions. */
+		if (!in_sched_functions(pc))
+			return pc;
+
+		fp = *(unsigned long *) fp;
+	} while (count++ < 16);
+
+	return 0;
+}
+
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+	/* Check whether the thread is blocked in resume() */
+	if (in_sched_functions(tsk->thread.pc))
+		return ((unsigned long *)tsk->thread.fp)[2];
+	else
+		return tsk->thread.pc;
+}
+
+int elf_check_arch(const struct elf32_hdr *hdr)
+{
+	unsigned long hsr0 = __get_HSR(0);
+	unsigned long psr = __get_PSR();
+
+	if (hdr->e_machine != EM_FRV)
+		return 0;
+
+	switch (hdr->e_flags & EF_FRV_GPR_MASK) {
+	case EF_FRV_GPR64:
+		if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
+			return 0;
+	case EF_FRV_GPR32:
+	case 0:
+		break;
+	default:
+		return 0;
+	}
+
+	switch (hdr->e_flags & EF_FRV_FPR_MASK) {
+	case EF_FRV_FPR64:
+		if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
+			return 0;
+	case EF_FRV_FPR32:
+	case EF_FRV_FPR_NONE:
+	case 0:
+		break;
+	default:
+		return 0;
+	}
+
+	if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
+		if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
+		    PSR_IMPLE(psr) != PSR_IMPLE_FR451)
+			return 0;
+
+	switch (hdr->e_flags & EF_FRV_CPU_MASK) {
+	case EF_FRV_CPU_GENERIC:
+		break;
+	case EF_FRV_CPU_FR300:
+	case EF_FRV_CPU_SIMPLE:
+	case EF_FRV_CPU_TOMCAT:
+	default:
+		return 0;
+	case EF_FRV_CPU_FR400:
+		if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
+		    PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
+		    PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
+		    PSR_IMPLE(psr) != PSR_IMPLE_FR551)
+			return 0;
+		break;
+	case EF_FRV_CPU_FR450:
+		if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
+			return 0;
+		break;
+	case EF_FRV_CPU_FR500:
+		if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
+			return 0;
+		break;
+	case EF_FRV_CPU_FR550:
+		if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
+			return 0;
+		break;
+	}
+
+	return 1;
+}