/*
* Copyright 2013 Tilera Corporation. All Rights Reserved.
*
* 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, version 2.
*
* 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, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* TILE-Gx KGDB support.
*/

#ifndef __TILE_KGDB_H__
#define __TILE_KGDB_H__

#include <linux/kdebug.h>
#include <arch/opcode.h>

#define GDB_SIZEOF_REG sizeof(unsigned long)

/*
* TILE-Gx gdb is expecting the following register layout:
* 56 GPRs(R0 - R52, TP, SP, LR), 8 special GPRs(networks and ZERO),
* plus the PC and the faultnum.
*
* Even though kernel not use the 8 special GPRs, they need to be present
* in the registers sent for correct processing in the host-side gdb.
*
*/
#define DBG_MAX_REG_NUM (56+8+2)
#define NUMREGBYTES (DBG_MAX_REG_NUM * GDB_SIZEOF_REG)

/*
* BUFMAX defines the maximum number of characters in inbound/outbound
* buffers at least NUMREGBYTES*2 are needed for register packets,
* Longer buffer is needed to list all threads.
*/
#define BUFMAX 2048

#define BREAK_INSTR_SIZE TILEGX_BUNDLE_SIZE_IN_BYTES

/*
* Require cache flush for set/clear a software breakpoint or write memory.
*/
#define CACHE_FLUSH_IS_SAFE 1

/*
* The compiled-in breakpoint instruction can be used to "break" into
* the debugger via magic system request key (sysrq-G).
*/
static tile_bundle_bits compiled_bpt = TILEGX_BPT_BUNDLE | DIE_COMPILED_BPT;

enum tilegx_regnum {
TILEGX_PC_REGNUM = TREG_LAST_GPR + 9,
TILEGX_FAULTNUM_REGNUM,
};

/*
* Generate a breakpoint exception to "break" into the debugger.
*/
static inline void arch_kgdb_breakpoint(void)
{
asm volatile (".quad %0\n\t"
::""(compiled_bpt));
}

#endif /* __TILE_KGDB_H__ */