kernel-ark/include/asm-blackfin/system.h
Mike Frysinger 1aafd90912 Blackfin arch: revise anomaly handling by basing things on the compiler not the kconfig defines
revise anomaly handling by basing things on the compiler not the kconfig defines,
so the header is stable and usable outside of the kernel. This also allows us to
move some code from preprocessing to compiling (gcc culls dead code)
which should help with code quality (readability, catch minor bugs, etc...).

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-07-25 11:19:14 +08:00

259 lines
6.3 KiB
C

/*
* File: include/asm/system.h
* Based on:
* Author: Tony Kou (tonyko@lineo.ca)
* Copyright (c) 2002 Arcturus Networks Inc.
* (www.arcturusnetworks.com)
* Copyright (c) 2003 Metrowerks (www.metrowerks.com)
* Copyright (c) 2004 Analog Device Inc.
* Created: 25Jan2001 - Tony Kou
* Description: system.h include file
*
* Modified: 22Sep2006 - Robin Getz
* - move include blackfin.h down, so I can get access to
* irq functions in other include files.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* 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, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING.
* If not, write to the Free Software Foundation,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _BLACKFIN_SYSTEM_H
#define _BLACKFIN_SYSTEM_H
#include <linux/linkage.h>
#include <linux/compiler.h>
#include <asm/mach/anomaly.h>
/*
* Interrupt configuring macros.
*/
extern unsigned long irq_flags;
#define local_irq_enable() \
__asm__ __volatile__( \
"sti %0;" \
: \
: "d" (irq_flags) \
)
#define local_irq_disable() \
do { \
int __tmp_dummy; \
__asm__ __volatile__( \
"cli %0;" \
: "=d" (__tmp_dummy) \
); \
} while (0)
#if ANOMALY_05000244 && defined(CONFIG_BLKFIN_CACHE)
# define NOP_PAD_ANOMALY_05000244 "nop; nop;"
#else
# define NOP_PAD_ANOMALY_05000244
#endif
#define idle_with_irq_disabled() \
__asm__ __volatile__( \
NOP_PAD_ANOMALY_05000244 \
".align 8;" \
"sti %0;" \
"idle;" \
: \
: "d" (irq_flags) \
)
#ifdef CONFIG_DEBUG_HWERR
# define __save_and_cli(x) \
__asm__ __volatile__( \
"cli %0;" \
"sti %1;" \
: "=&d" (x) \
: "d" (0x3F) \
)
#else
# define __save_and_cli(x) \
__asm__ __volatile__( \
"cli %0;" \
: "=&d" (x) \
)
#endif
#define local_save_flags(x) \
__asm__ __volatile__( \
"cli %0;" \
"sti %0;" \
: "=d" (x) \
)
#ifdef CONFIG_DEBUG_HWERR
#define irqs_enabled_from_flags(x) (((x) & ~0x3f) != 0)
#else
#define irqs_enabled_from_flags(x) ((x) != 0x1f)
#endif
#define local_irq_restore(x) \
do { \
if (irqs_enabled_from_flags(x)) \
local_irq_enable(); \
} while (0)
/* For spinlocks etc */
#define local_irq_save(x) __save_and_cli(x)
#define irqs_disabled() \
({ \
unsigned long flags; \
local_save_flags(flags); \
!irqs_enabled_from_flags(flags); \
})
/*
* 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_rmb(var, value) do { (void) xchg(&var, value); } while (0)
#define set_mb(var, value) set_rmb(var, value)
#define set_wmb(var, value) do { var = value; wmb(); } while (0)
#define read_barrier_depends() do { } while(0)
#ifdef CONFIG_SMP
#define smp_mb() mb()
#define smp_rmb() rmb()
#define smp_wmb() wmb()
#define smp_read_barrier_depends() read_barrier_depends()
#else
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#define smp_read_barrier_depends() do { } while(0)
#endif
#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
struct __xchg_dummy {
unsigned long a[100];
};
#define __xg(x) ((volatile struct __xchg_dummy *)(x))
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
int size)
{
unsigned long tmp = 0;
unsigned long flags = 0;
local_irq_save(flags);
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;
}
local_irq_restore(flags);
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 = 0;
unsigned long flags = 0;
local_irq_save(flags);
switch (size) {
case 1:
__asm__ __volatile__
("%0 = b%3 (z);\n\t"
"CC = %1 == %0;\n\t"
"IF !CC JUMP 1f;\n\t"
"b%3 = %2;\n\t"
"1:\n\t"
: "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
break;
case 2:
__asm__ __volatile__
("%0 = w%3 (z);\n\t"
"CC = %1 == %0;\n\t"
"IF !CC JUMP 1f;\n\t"
"w%3 = %2;\n\t"
"1:\n\t"
: "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
break;
case 4:
__asm__ __volatile__
("%0 = %3;\n\t"
"CC = %1 == %0;\n\t"
"IF !CC JUMP 1f;\n\t"
"%3 = %2;\n\t"
"1:\n\t"
: "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
break;
}
local_irq_restore(flags);
return tmp;
}
#define cmpxchg(ptr,o,n)\
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
(unsigned long)(n),sizeof(*(ptr))))
#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/blackfin.h>
asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_struct *next);
#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)
#endif /* _BLACKFIN_SYSTEM_H */