/*
 * include/asm-xtensa/ptrace.h
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2001 - 2005 Tensilica Inc.
 */
#ifndef _XTENSA_PTRACE_H
#define _XTENSA_PTRACE_H

#include <asm/kmem_layout.h>
#include <uapi/asm/ptrace.h>

/*
 * Kernel stack
 *
 *              +-----------------------+  -------- STACK_SIZE
 *              |     register file     |  |
 *              +-----------------------+  |
 *              |    struct pt_regs     |  |
 *              +-----------------------+  | ------ PT_REGS_OFFSET
 * double       :  16 bytes spill area  :  |  ^
 * excetion     :- - - - - - - - - - - -:  |  |
 * frame        :    struct pt_regs     :  |  |
 *              :- - - - - - - - - - - -:  |  |
 *              |                       |  |  |
 *              |     memory stack      |  |  |
 *              |                       |  |  |
 *              ~                       ~  ~  ~
 *              ~                       ~  ~  ~
 *              |                       |  |  |
 *              |                       |  |  |
 *              +-----------------------+  |  | --- STACK_BIAS
 *              |  struct task_struct   |  |  |  ^
 *  current --> +-----------------------+  |  |  |
 *              |  struct thread_info   |  |  |  |
 *              +-----------------------+ --------
 */

#define NO_SYSCALL (-1)

#ifndef __ASSEMBLER__

#include <asm/coprocessor.h>
#include <asm/core.h>

/*
 * This struct defines the way the registers are stored on the
 * kernel stack during a system call or other kernel entry.
 */
struct pt_regs {
        unsigned long pc;               /*   4 */
        unsigned long ps;               /*   8 */
        unsigned long depc;             /*  12 */
        unsigned long exccause;         /*  16 */
        unsigned long excvaddr;         /*  20 */
        unsigned long debugcause;       /*  24 */
        unsigned long wmask;            /*  28 */
        unsigned long lbeg;             /*  32 */
        unsigned long lend;             /*  36 */
        unsigned long lcount;           /*  40 */
        unsigned long sar;              /*  44 */
        unsigned long windowbase;       /*  48 */
        unsigned long windowstart;      /*  52 */
        unsigned long syscall;          /*  56 */
        unsigned long icountlevel;      /*  60 */
        unsigned long scompare1;        /*  64 */
        unsigned long threadptr;        /*  68 */

        /* Additional configurable registers that are used by the compiler. */
        xtregs_opt_t xtregs_opt;

        /* current register frame.
         * Note: The ESF for kernel exceptions ends after 16 registers!
         */
        unsigned long areg[XCHAL_NUM_AREGS] __aligned(16);
};

# define arch_has_single_step() (1)
# define task_pt_regs(tsk) ((struct pt_regs*) \
        (task_stack_page(tsk) + KERNEL_STACK_SIZE) - 1)
# define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
# define instruction_pointer(regs) ((regs)->pc)
# define return_pointer(regs) (MAKE_PC_FROM_RA((regs)->areg[0], \
                                               (regs)->pc))

# ifndef CONFIG_SMP
#  define profile_pc(regs) instruction_pointer(regs)
# else
#  define profile_pc(regs)                                              \
        ({                                                              \
                in_lock_functions(instruction_pointer(regs)) ?          \
                return_pointer(regs) : instruction_pointer(regs);       \
        })
# endif

#define user_stack_pointer(regs) ((regs)->areg[1])

static inline unsigned long regs_return_value(struct pt_regs *regs)
{
        return regs->areg[2];
}

int do_syscall_trace_enter(struct pt_regs *regs);
void do_syscall_trace_leave(struct pt_regs *regs);

#else   /* __ASSEMBLER__ */

# include <asm/asm-offsets.h>
#define PT_REGS_OFFSET    (KERNEL_STACK_SIZE - PT_USER_SIZE)

#endif  /* !__ASSEMBLER__ */

#endif  /* _XTENSA_PTRACE_H */