/*
* Copyright 2004-2009 Analog Devices Inc.
* Tony Kou (tonyko@lineo.ca)
*
* Licensed under the GPL-2 or later
*/
#ifndef _BLACKFIN_SYSTEM_H
#define _BLACKFIN_SYSTEM_H
#include <linux/linkage.h>
#include <linux/irqflags.h>
#include <mach/anomaly.h>
#include <asm/cache.h>
#include <asm/pda.h>
#include <asm/irq.h>
/*
* Force strict CPU ordering.
*/
#define nop() __asm__ __volatile__ ("nop;\n\t" : : )
#define mb() __asm__ __volatile__ ("" : : : "memory")
#define rmb() __asm__ __volatile__ ("" : : : "memory")
#define wmb() __asm__ __volatile__ ("" : : : "memory")
#define set_mb(var, value) do { (void) xchg(&var, value); } while (0)
#define read_barrier_depends() do { } while(0)
#ifdef CONFIG_SMP
asmlinkage unsigned long __raw_xchg_1_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_xchg_2_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_xchg_4_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_cmpxchg_1_asm(volatile void *ptr,
unsigned long new, unsigned long old);
asmlinkage unsigned long __raw_cmpxchg_2_asm(volatile void *ptr,
unsigned long new, unsigned long old);
asmlinkage unsigned long __raw_cmpxchg_4_asm(volatile void *ptr,
unsigned long new, unsigned long old);
#ifdef __ARCH_SYNC_CORE_DCACHE
# define smp_mb() do { barrier(); smp_check_barrier(); smp_mark_barrier(); } while (0)
# define smp_rmb() do { barrier(); smp_check_barrier(); } while (0)
# define smp_wmb() do { barrier(); smp_mark_barrier(); } while (0)
#define smp_read_barrier_depends() do { barrier(); smp_check_barrier(); } while (0)
#else
# define smp_mb() barrier()
# define smp_rmb() barrier()
# define smp_wmb() barrier()
#define smp_read_barrier_depends() barrier()
#endif
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
int size)
{
unsigned long tmp;
switch (size) {
case 1:
tmp = __raw_xchg_1_asm(ptr, x);
break;
case 2:
tmp = __raw_xchg_2_asm(ptr, x);
break;
case 4:
tmp = __raw_xchg_4_asm(ptr, x);
break;
}
return tmp;
}
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
unsigned long new, int size)
{
unsigned long tmp;
switch (size) {
case 1:
tmp = __raw_cmpxchg_1_asm(ptr, new, old);
break;
case 2:
tmp = __raw_cmpxchg_2_asm(ptr, new, old);
break;
case 4:
tmp = __raw_cmpxchg_4_asm(ptr, new, old);
break;
}
return tmp;
}
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#else /* !CONFIG_SMP */
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#define smp_read_barrier_depends() do { } while(0)
struct __xchg_dummy {
unsigned long a[100];
};
#define __xg(x) ((volatile struct __xchg_dummy *)(x))
#include <mach/blackfin.h>
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
int size)
{
unsigned long tmp = 0;
unsigned long flags;
flags = hard_local_irq_save();
switch (size) {
case 1:
__asm__ __volatile__
("%0 = b%2 (z);\n\t"
"b%2 = %1;\n\t"
: "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
case 2:
__asm__ __volatile__
("%0 = w%2 (z);\n\t"
"w%2 = %1;\n\t"
: "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
case 4:
__asm__ __volatile__
("%0 = %2;\n\t"
"%2 = %1;\n\t"
: "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
}
hard_local_irq_restore(flags);
return tmp;
}
#include <asm-generic/cmpxchg-local.h>
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
#include <asm-generic/cmpxchg.h>
#endif /* !CONFIG_SMP */
#define xchg(ptr, x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
#define tas(ptr) ((void)xchg((ptr), 1))
#define prepare_to_switch() do { } while(0)
/*
* switch_to(n) should switch tasks to task ptr, first checking that
* ptr isn't the current task, in which case it does nothing.
*/
#include <asm/l1layout.h>
#include <asm/mem_map.h>
asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_struct *next);
#ifndef CONFIG_SMP
#define switch_to(prev,next,last) \
do { \
memcpy (&task_thread_info(prev)->l1_task_info, L1_SCRATCH_TASK_INFO, \
sizeof *L1_SCRATCH_TASK_INFO); \
memcpy (L1_SCRATCH_TASK_INFO, &task_thread_info(next)->l1_task_info, \
sizeof *L1_SCRATCH_TASK_INFO); \
(last) = resume (prev, next); \
} while (0)
#else
#define switch_to(prev, next, last) \
do { \
(last) = resume(prev, next); \
} while (0)
#endif
#endif /* _BLACKFIN_SYSTEM_H */
