1/* processor.h: FRV processor definitions
  2 *
  3 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
  4 * Written by David Howells (dhowells@redhat.com)
  5 *
  6 * This program is free software; you can redistribute it and/or
  7 * modify it under the terms of the GNU General Public License
  8 * as published by the Free Software Foundation; either version
  9 * 2 of the License, or (at your option) any later version.
 10 */
 11
 12#ifndef _ASM_PROCESSOR_H
 13#define _ASM_PROCESSOR_H
 14
 15#include <asm/mem-layout.h>
 16
 17#ifndef __ASSEMBLY__
 18/*
 19 * Default implementation of macro that returns current
 20 * instruction pointer ("program counter").
 21 */
 22#define current_text_addr() ({ __label__ _l; _l: &&_l;})
 23
 24#include <linux/compiler.h>
 25#include <linux/linkage.h>
 26#include <asm/sections.h>
 27#include <asm/segment.h>
 28#include <asm/fpu.h>
 29#include <asm/registers.h>
 30#include <asm/ptrace.h>
 31#include <asm/current.h>
 32#include <asm/cache.h>
 33
 34/* Forward declaration, a strange C thing */
 35struct task_struct;
 36
 37/*
 38 * Bus types
 39 */
 40#define EISA_bus 0
 41
 42struct thread_struct {
 43	struct pt_regs		*frame;		/* [GR28] exception frame ptr for this thread */
 44	struct task_struct	*curr;		/* [GR29] current pointer for this thread */
 45	unsigned long		sp;		/* [GR1 ] kernel stack pointer */
 46	unsigned long		fp;		/* [GR2 ] kernel frame pointer */
 47	unsigned long		lr;		/* link register */
 48	unsigned long		pc;		/* program counter */
 49	unsigned long		gr[12];		/* [GR16-GR27] */
 50	unsigned long		sched_lr;	/* LR from schedule() */
 51
 52	union {
 53		struct pt_regs		*frame0;	/* top (user) stack frame */
 54		struct user_context	*user;		/* userspace context */
 55	};
 56} __attribute__((aligned(8)));
 57
 58extern struct pt_regs *__kernel_frame0_ptr;
 59extern struct task_struct *__kernel_current_task;
 60
 61#endif
 62
 63#ifndef __ASSEMBLY__
 64#define INIT_THREAD_FRAME0 \
 65	((struct pt_regs *) \
 66	(sizeof(init_stack) + (unsigned long) init_stack - sizeof(struct user_context)))
 67
 68#define INIT_THREAD {				\
 69	NULL,					\
 70	(struct task_struct *) init_stack,	\
 71	0, 0, 0, 0,				\
 72	{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },	\
 73	0,					\
 74	{ INIT_THREAD_FRAME0 },			\
 75}
 76
 77/*
 78 * do necessary setup to start up a newly executed thread.
 79 */
 80#define start_thread(_regs, _pc, _usp)			\
 81do {							\
 82	_regs->pc	= (_pc);			\
 83	_regs->psr	&= ~PSR_S;			\
 84	_regs->sp	= (_usp);			\
 85} while(0)
 86
 87/* Free all resources held by a thread. */
 88static inline void release_thread(struct task_struct *dead_task)
 89{
 90}
 91
 92extern asmlinkage void save_user_regs(struct user_context *target);
 93extern asmlinkage void *restore_user_regs(const struct user_context *target, ...);
 94
 95#define copy_segments(tsk, mm)		do { } while (0)
 96#define release_segments(mm)		do { } while (0)
 97#define forget_segments()		do { } while (0)
 98
 99/*
100 * Free current thread data structures etc..
101 */
102static inline void exit_thread(void)
103{
104}
105
106/*
107 * Return saved PC of a blocked thread.
108 */
109extern unsigned long thread_saved_pc(struct task_struct *tsk);
110
111unsigned long get_wchan(struct task_struct *p);
112
113#define	KSTK_EIP(tsk)	((tsk)->thread.frame0->pc)
114#define	KSTK_ESP(tsk)	((tsk)->thread.frame0->sp)
115
116#define cpu_relax() barrier()
117#define cpu_relax_lowlatency() cpu_relax()
118
119/* data cache prefetch */
120#define ARCH_HAS_PREFETCH
121static inline void prefetch(const void *x)
122{
123	asm volatile("dcpl %0,gr0,#0" : : "r"(x));
124}
125
126#endif /* __ASSEMBLY__ */
127#endif /* _ASM_PROCESSOR_H */