diff options
Diffstat (limited to 'arch/mips/include/asm/irq.h')
| -rw-r--r-- | arch/mips/include/asm/irq.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h index 956db6e201d1..ddd1c918103b 100644 --- a/arch/mips/include/asm/irq.h +++ b/arch/mips/include/asm/irq.h @@ -18,9 +18,24 @@ #include <irq.h> #define IRQ_STACK_SIZE THREAD_SIZE +#define IRQ_STACK_START (IRQ_STACK_SIZE - sizeof(unsigned long)) extern void *irq_stack[NR_CPUS]; +/* + * The highest address on the IRQ stack contains a dummy frame put down in + * genex.S (handle_int & except_vec_vi_handler) which is structured as follows: + * + * top ------------ + * | task sp | <- irq_stack[cpu] + IRQ_STACK_START + * ------------ + * | | <- First frame of IRQ context + * ------------ + * + * task sp holds a copy of the task stack pointer where the struct pt_regs + * from exception entry can be found. + */ + static inline bool on_irq_stack(int cpu, unsigned long sp) { unsigned long low = (unsigned long)irq_stack[cpu]; |