/*
* 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>
/*
* Interrupt configuring macros.
*/
extern unsigned long irq_flags;
#define local_irq_enable() do { \
__asm__ __volatile__ ( \
"sti %0;" \
::"d"(irq_flags)); \
} while (0)
#define local_irq_disable() do { \
int _tmp_dummy; \
__asm__ __volatile__ ( \
"cli %0;" \
:"=d" (_tmp_dummy):); \
} while (0)
#if defined(ANOMALY_05000244) && defined (CONFIG_BLKFIN_CACHE)
#define idle_with_irq_disabled() do { \
__asm__ __volatile__ ( \
"nop; nop;\n" \
".align 8;\n" \
"sti %0; idle;\n" \
::"d" (irq_flags)); \
} while (0)
#else
#define idle_with_irq_disabled() do { \
__asm__ __volatile__ ( \
".align 8;\n" \
"sti %0; idle;\n" \
::"d" (irq_flags)); \
} while (0)
#endif
#ifdef CONFIG_DEBUG_HWERR
#define __save_and_cli(x) do { \
__asm__ __volatile__ ( \
"cli %0;\n\tsti %1;" \
:"=&d"(x): "d" (0x3F)); \
} while (0)
#else
#define __save_and_cli(x) do { \
__asm__ __volatile__ ( \
"cli %0;" \
:"=&d"(x):); \
} while (0)
#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))))
#define tas(ptr) ((void)xchg((ptr),1))
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 (&prev->thread_info->l1_task_info, L1_SCRATCH_TASK_INFO, \
sizeof *L1_SCRATCH_TASK_INFO); \
memcpy (L1_SCRATCH_TASK_INFO, &next->thread_info->l1_task_info, \
sizeof *L1_SCRATCH_TASK_INFO); \
(last) = resume (prev, next); \
} while (0)
#endif /* _BLACKFIN_SYSTEM_H */
