/*
* OpenRISC Linux
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* OpenRISC implementation:
* Copyright (C) 2003 Matjaz Breskvar <[email protected]>
* Copyright (C) 2010-2011 Jonas Bonn <[email protected]>
* et al.
*
* 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 of the License, or
* (at your option) any later version.
*/
#ifndef __ASM_OPENRISC_PTRACE_H
#define __ASM_OPENRISC_PTRACE_H


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

/*
* Make kernel PTrace/register structures opaque to userspace... userspace can
* access thread state via the regset mechanism. This allows us a bit of
* flexibility in how we order the registers on the stack, permitting some
* optimizations like packing call-clobbered registers together so that
* they share a cacheline (not done yet, though... future optimization).
*/

#ifndef __ASSEMBLY__
/*
* This struct describes how the registers are laid out on the kernel stack
* during a syscall or other kernel entry.
*
* This structure should always be cacheline aligned on the stack.
* FIXME: I don't think that's the case right now. The alignment is
* taken care of elsewhere... head.S, process.c, etc.
*/

struct pt_regs {
union {
struct {
/* Named registers */
long sr; /* Stored in place of r0 */
long sp; /* r1 */
};
struct {
/* Old style */
long offset[2];
long gprs[30];
};
struct {
/* New style */
long gpr[32];
};
};
long pc;
/* For restarting system calls:
* Set to syscall number for syscall exceptions,
* -1 for all other exceptions.
*/
long orig_gpr11; /* For restarting system calls */
long dummy; /* Cheap alignment fix */
long dummy2; /* Cheap alignment fix */
};

/* TODO: Rename this to REDZONE because that's what it is */
#define STACK_FRAME_OVERHEAD 128 /* size of minimum stack frame */

#define instruction_pointer(regs) ((regs)->pc)
#define user_mode(regs) (((regs)->sr & SPR_SR_SM) == 0)
#define user_stack_pointer(regs) ((unsigned long)(regs)->sp)
#define profile_pc(regs) instruction_pointer(regs)

static inline long regs_return_value(struct pt_regs *regs)
{
return regs->gpr[11];
}

#endif /* __ASSEMBLY__ */

/*
* Offsets used by 'ptrace' system call interface.
*/
#define PT_SR 0
#define PT_SP 4
#define PT_GPR2 8
#define PT_GPR3 12
#define PT_GPR4 16
#define PT_GPR5 20
#define PT_GPR6 24
#define PT_GPR7 28
#define PT_GPR8 32
#define PT_GPR9 36
#define PT_GPR10 40
#define PT_GPR11 44
#define PT_GPR12 48
#define PT_GPR13 52
#define PT_GPR14 56
#define PT_GPR15 60
#define PT_GPR16 64
#define PT_GPR17 68
#define PT_GPR18 72
#define PT_GPR19 76
#define PT_GPR20 80
#define PT_GPR21 84
#define PT_GPR22 88
#define PT_GPR23 92
#define PT_GPR24 96
#define PT_GPR25 100
#define PT_GPR26 104
#define PT_GPR27 108
#define PT_GPR28 112
#define PT_GPR29 116
#define PT_GPR30 120
#define PT_GPR31 124
#define PT_PC 128
#define PT_ORIG_GPR11 132
#define PT_SYSCALLNO 136

#endif /* __ASM_OPENRISC_PTRACE_H */