Files
codezero/include/l4/arch/arm/exception.h
Bahadir Balban e2b791a3d8 Initial commit
2008-01-13 13:53:52 +00:00

89 lines
1.8 KiB
C

/*
* Definitions for exception support on ARM
*
* Copyright (C) 2007 Bahadir Balban
*/
#ifndef __ARCH_EXCEPTIONS_H__
#define __ARCH_EXCEPTIONS_H__
#include INC_ARCH(asm.h)
static inline void enable_irqs()
{
__asm__ __volatile__(
"mrs r0, cpsr_fc\n"
"bic r0, r0, #0x80\n" /* ARM_IRQ_BIT */
"msr cpsr_fc, r0\n"
);
}
static inline int irqs_enabled()
{
register unsigned int enabled asm("r1");
__asm__ __volatile__(
"mrs r0, cpsr_fc\n"
"tst r0, #0x80\n" /* ARM_IRQ_BIT. See asm.h for TST inst. */
"moveq r1, #1\n"
"movne r1, #0\n"
);
return enabled;
}
static inline void disable_irqs()
{
__asm__ __volatile__(
"mrs r0, cpsr_fc\n"
"orr r0, r0, #0x80\n" /* ARM_IRQ_BIT */
"msr cpsr_fc, r0\n"
);
}
#if 0 /* These will be useful for nested irq disable/enable calls */
/* Disable the irqs unconditionally, but also keep the previous state such that
* if it was already disabled before the call, the restore call would retain
* this state. */
static inline void irq_local_disable_save(unsigned long *flags)
{
unsigned long temp;
__asm__ __volatile__ (
"mrs %0, cpsr_fc\n"
"orr %1, %0, #0x80\n"
"msr cpsr_fc, %1\n"
: "=r"(*flags), "=r" (temp)
);
}
/* Simply change it back to original state supplied in @flags. This might enable
* or retain disabled state of the irqs for example. Useful for nested calls. */
static inline void irq_local_restore(unsigned long flags)
{
__asm__ __volatile__ (
"msr cpsr_fc, %0\n"
: "r" (flags)
);
}
#endif
static inline void irq_local_enable()
{
enable_irqs();
}
static inline void irq_local_disable()
{
disable_irqs();
}
/* This is filled on entry to irq handler, only if a process was interrupted.*/
extern unsigned int preempted_psr;
static inline int in_kernel()
{
return (((preempted_psr & ARM_MODE_MASK) == ARM_MODE_SVC)) ? 1 : 0;
}
static inline int in_user()
{
return !in_kernel();
}
#endif