[linux-block.git] / include / asm-avr32 / system.h

/*
 * Copyright (C) 2004-2006 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef __ASM_AVR32_SYSTEM_H
#define __ASM_AVR32_SYSTEM_H

#include <linux/compiler.h>
#include <linux/types.h>

#include <asm/ptrace.h>
#include <asm/sysreg.h>

#define xchg(ptr,x) \
	((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))

#define nop() asm volatile("nop")

#define mb()			asm volatile("" : : : "memory")
#define rmb()			mb()
#define wmb()			asm volatile("sync 0" : : : "memory")
#define read_barrier_depends()  do { } while(0)
#define set_mb(var, value)      do { var = value; mb(); } while(0)

/*
 * Help PathFinder and other Nexus-compliant debuggers keep track of
 * the current PID by emitting an Ownership Trace Message each time we
 * switch task.
 */
#ifdef CONFIG_OWNERSHIP_TRACE
#include <asm/ocd.h>
#define finish_arch_switch(prev)			\
	do {						\
		__mtdr(DBGREG_PID, prev->pid);		\
		__mtdr(DBGREG_PID, current->pid);	\
	} while(0)
#endif

/*
 * switch_to(prev, next, last) should switch from task `prev' to task
 * `next'. `prev' will never be the same as `next'.
 *
 * We just delegate everything to the __switch_to assembly function,
 * which is implemented in arch/avr32/kernel/switch_to.S
 *
 * mb() tells GCC not to cache `current' across this call.
 */
struct cpu_context;
struct task_struct;
extern struct task_struct *__switch_to(struct task_struct *,
				       struct cpu_context *,
				       struct cpu_context *);
#define switch_to(prev, next, last)					\
	do {								\
		last = __switch_to(prev, &prev->thread.cpu_context + 1,	\
				   &next->thread.cpu_context);		\
	} while (0)

#ifdef CONFIG_SMP
# error "The AVR32 port does not support SMP"
#else
# define smp_mb()		barrier()
# define smp_rmb()		barrier()
# define smp_wmb()		barrier()
# define smp_read_barrier_depends() do { } while(0)
#endif

#include <linux/irqflags.h>

extern void __xchg_called_with_bad_pointer(void);

#ifdef __CHECKER__
extern unsigned long __builtin_xchg(void *ptr, unsigned long x);
#endif

#define xchg_u32(val, m) __builtin_xchg((void *)m, val)

static inline unsigned long __xchg(unsigned long x,
				       volatile void *ptr,
				       int size)
{
	switch(size) {
	case 4:
		return xchg_u32(x, ptr);
	default:
		__xchg_called_with_bad_pointer();
		return x;
	}
}

static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
					  unsigned long new)
{
	__u32 ret;

	asm volatile(
		"1:	ssrf	5\n"
		"	ld.w	%[ret], %[m]\n"
		"	cp.w	%[ret], %[old]\n"
		"	brne	2f\n"
		"	stcond	%[m], %[new]\n"
		"	brne	1b\n"
		"2:\n"
		: [ret] "=&r"(ret), [m] "=m"(*m)
		: "m"(m), [old] "ir"(old), [new] "r"(new)
		: "memory", "cc");
	return ret;
}

extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels(
        volatile int * m, unsigned long old, unsigned long new);
#define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels

/* This function doesn't exist, so you'll get a linker error
   if something tries to do an invalid cmpxchg().  */
extern void __cmpxchg_called_with_bad_pointer(void);

#define __HAVE_ARCH_CMPXCHG 1

static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
				      unsigned long new, int size)
{
	switch (size) {
	case 4:
		return __cmpxchg_u32(ptr, old, new);
	case 8:
		return __cmpxchg_u64(ptr, old, new);
	}

	__cmpxchg_called_with_bad_pointer();
	return old;
}

#define cmpxchg(ptr, old, new)					\
	((typeof(*(ptr)))__cmpxchg((ptr), (unsigned long)(old),	\
				   (unsigned long)(new),	\
				   sizeof(*(ptr))))

struct pt_regs;
extern void __die(const char *, struct pt_regs *, unsigned long,
		  const char *, const char *, unsigned long);
extern void __die_if_kernel(const char *, struct pt_regs *, unsigned long,
			    const char *, const char *, unsigned long);

#define die(msg, regs, err)					\
	__die(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)
#define die_if_kernel(msg, regs, err)					\
	__die_if_kernel(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)

#define arch_align_stack(x)	(x)

#endif /* __ASM_AVR32_SYSTEM_H */
Commit	Line	Data
5f97f7f9 HS	1	/*
	2	* Copyright (C) 2004-2006 Atmel Corporation
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8	#ifndef __ASM_AVR32_SYSTEM_H
	9	#define __ASM_AVR32_SYSTEM_H
	10
	11	#include <linux/compiler.h>
	12	#include <linux/types.h>
	13
	14	#include <asm/ptrace.h>
	15	#include <asm/sysreg.h>
	16
	17	#define xchg(ptr,x) \
	18	((__typeof__((ptr)))__xchg((unsigned long)(x),(ptr),sizeof((ptr))))
	19
	20	#define nop() asm volatile("nop")
	21
	22	#define mb() asm volatile("" : : : "memory")
	23	#define rmb() mb()
	24	#define wmb() asm volatile("sync 0" : : : "memory")
	25	#define read_barrier_depends() do { } while(0)
	26	#define set_mb(var, value) do { var = value; mb(); } while(0)
	27
	28	/*
	29	* Help PathFinder and other Nexus-compliant debuggers keep track of
	30	* the current PID by emitting an Ownership Trace Message each time we
	31	* switch task.
	32	*/
	33	#ifdef CONFIG_OWNERSHIP_TRACE
	34	#include <asm/ocd.h>
	35	#define finish_arch_switch(prev) \
	36	do { \
	37	__mtdr(DBGREG_PID, prev->pid); \
	38	__mtdr(DBGREG_PID, current->pid); \
	39	} while(0)
	40	#endif
	41
	42	/*
	43	* switch_to(prev, next, last) should switch from task `prev' to task
	44	* `next'. `prev' will never be the same as `next'.
	45	*
	46	* We just delegate everything to the __switch_to assembly function,
	47	* which is implemented in arch/avr32/kernel/switch_to.S
	48	*
	49	* mb() tells GCC not to cache `current' across this call.
	50	*/
	51	struct cpu_context;
	52	struct task_struct;
	53	extern struct task_struct __switch_to(struct task_struct ,
	54	struct cpu_context *,
	55	struct cpu_context *);
	56	#define switch_to(prev, next, last) \
	57	do { \
	58	last = __switch_to(prev, &prev->thread.cpu_context + 1, \
	59	&next->thread.cpu_context); \
	60	} while (0)
	61
	62	#ifdef CONFIG_SMP
	63	# error "The AVR32 port does not support SMP"
	64	#else
65	# define smp_mb() barrier()
66	# define smp_rmb() barrier()
67	# define smp_wmb() barrier()
68	# define smp_read_barrier_depends() do { } while(0)
69	#endif
70
71	#include <linux/irqflags.h>
72
73	extern void __xchg_called_with_bad_pointer(void);
74
75	#ifdef __CHECKER__
76	extern unsigned long __builtin_xchg(void *ptr, unsigned long x);
77	#endif
78
79	#define xchg_u32(val, m) __builtin_xchg((void *)m, val)
80
81	static inline unsigned long __xchg(unsigned long x,
82	volatile void *ptr,
83	int size)
84	{
85	switch(size) {
86	case 4:
87	return xchg_u32(x, ptr);
88	default:
89	__xchg_called_with_bad_pointer();
90	return x;
91	}
92	}
93
94	static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
95	unsigned long new)
96	{
97	__u32 ret;
98
99	asm volatile(
100	"1: ssrf 5\n"
101	" ld.w %[ret], %[m]\n"
102	" cp.w %[ret], %[old]\n"
103	" brne 2f\n"
104	" stcond %[m], %[new]\n"
105	" brne 1b\n"
106	"2:\n"
107	: [ret] "=&r"(ret), [m] "=m"(*m)
108	: "m"(m), [old] "ir"(old), [new] "r"(new)
109	: "memory", "cc");
110	return ret;
111	}
112
113	extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels(
114	volatile int * m, unsigned long old, unsigned long new);
115	#define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels
116
117	/* This function doesn't exist, so you'll get a linker error
118	if something tries to do an invalid cmpxchg(). */
119	extern void __cmpxchg_called_with_bad_pointer(void);
120
121	#define __HAVE_ARCH_CMPXCHG 1
122
123	static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
124	unsigned long new, int size)
125	{
126	switch (size) {
127	case 4:
128	return __cmpxchg_u32(ptr, old, new);
129	case 8:
130	return __cmpxchg_u64(ptr, old, new);
131	}
132
133	__cmpxchg_called_with_bad_pointer();
134	return old;
135	}
136
137	#define cmpxchg(ptr, old, new) \
138	((typeof(*(ptr)))__cmpxchg((ptr), (unsigned long)(old), \
139	(unsigned long)(new), \
140	sizeof(*(ptr))))
141
142	struct pt_regs;
143	extern void __die(const char , struct pt_regs , unsigned long,
144	const char , const char , unsigned long);
145	extern void __die_if_kernel(const char , struct pt_regs , unsigned long,
146	const char , const char , unsigned long);
147
148	#define die(msg, regs, err) \
149	__die(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)
150	#define die_if_kernel(msg, regs, err) \
151	__die_if_kernel(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)
152
153	#define arch_align_stack(x) (x)
154
155	#endif /* __ASM_AVR32_SYSTEM_H */