// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Mapping of DWARF debug register numbers into register names.
*
* Copyright (C) 2010 Ian Munsie, IBM Corporation.
*/
#include <stddef.h>
#include <errno.h>
#include <string.h>
#include <dwarf-regs.h>
#include <linux/ptrace.h>
#include <linux/kernel.h>
#include <linux/stringify.h>
struct pt_regs_dwarfnum {
const char *name;
unsigned int dwarfnum;
unsigned int ptregs_offset;
};
#define REG_DWARFNUM_NAME(r, num) \
{.name = __stringify(%)__stringify(r), .dwarfnum = num, \
.ptregs_offset = offsetof(struct pt_regs, r)}
#define GPR_DWARFNUM_NAME(num) \
{.name = __stringify(%gpr##num), .dwarfnum = num, \
.ptregs_offset = offsetof(struct pt_regs, gpr[num])}
#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0, .ptregs_offset = 0}
/*
* Reference:
* http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi-1.9.html
*/
static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
GPR_DWARFNUM_NAME(0),
GPR_DWARFNUM_NAME(1),
GPR_DWARFNUM_NAME(2),
GPR_DWARFNUM_NAME(3),
GPR_DWARFNUM_NAME(4),
GPR_DWARFNUM_NAME(5),
GPR_DWARFNUM_NAME(6),
GPR_DWARFNUM_NAME(7),
GPR_DWARFNUM_NAME(8),
GPR_DWARFNUM_NAME(9),
GPR_DWARFNUM_NAME(10),
GPR_DWARFNUM_NAME(11),
GPR_DWARFNUM_NAME(12),
GPR_DWARFNUM_NAME(13),
GPR_DWARFNUM_NAME(14),
GPR_DWARFNUM_NAME(15),
GPR_DWARFNUM_NAME(16),
GPR_DWARFNUM_NAME(17),
GPR_DWARFNUM_NAME(18),
GPR_DWARFNUM_NAME(19),
GPR_DWARFNUM_NAME(20),
GPR_DWARFNUM_NAME(21),
GPR_DWARFNUM_NAME(22),
GPR_DWARFNUM_NAME(23),
GPR_DWARFNUM_NAME(24),
GPR_DWARFNUM_NAME(25),
GPR_DWARFNUM_NAME(26),
GPR_DWARFNUM_NAME(27),
GPR_DWARFNUM_NAME(28),
GPR_DWARFNUM_NAME(29),
GPR_DWARFNUM_NAME(30),
GPR_DWARFNUM_NAME(31),
REG_DWARFNUM_NAME(msr, 66),
REG_DWARFNUM_NAME(ctr, 109),
REG_DWARFNUM_NAME(link, 108),
REG_DWARFNUM_NAME(xer, 101),
REG_DWARFNUM_NAME(dar, 119),
REG_DWARFNUM_NAME(dsisr, 118),
REG_DWARFNUM_END,
};
/**
* get_arch_regstr() - lookup register name from it's DWARF register number
* @n: the DWARF register number
*
* get_arch_regstr() returns the name of the register in struct
* regdwarfnum_table from it's DWARF register number. If the register is not
* found in the table, this returns NULL;
*/
const char *get_arch_regstr(unsigned int n)
{
const struct pt_regs_dwarfnum *roff;
for (roff = regdwarfnum_table; roff->name != NULL; roff++)
if (roff->dwarfnum == n)
return roff->name;
return NULL;
}
int regs_query_register_offset(const char *name)
{
const struct pt_regs_dwarfnum *roff;
for (roff = regdwarfnum_table; roff->name != NULL; roff++)
if (!strcmp(roff->name, name))
return roff->ptregs_offset;
return -EINVAL;
}
#define PPC_OP(op) (((op) >> 26) & 0x3F)
#define PPC_RA(a) (((a) >> 16) & 0x1f)
#define PPC_RT(t) (((t) >> 21) & 0x1f)
#define PPC_RB(b) (((b) >> 11) & 0x1f)
#define PPC_D(D) ((D) & 0xfffe)
#define PPC_DS(DS) ((DS) & 0xfffc)
#define OP_LD 58
#define OP_STD 62
static int get_source_reg(u32 raw_insn)
{
return PPC_RA(raw_insn);
}
static int get_target_reg(u32 raw_insn)
{
return PPC_RT(raw_insn);
}
static int get_offset_opcode(u32 raw_insn)
{
int opcode = PPC_OP(raw_insn);
/* DS- form */
if ((opcode == OP_LD) || (opcode == OP_STD))
return PPC_DS(raw_insn);
else
return PPC_D(raw_insn);
}
/*
* Fills the required fields for op_loc depending on if it
* is a source or target.
* D form: ins RT,D(RA) -> src_reg1 = RA, offset = D, dst_reg1 = RT
* DS form: ins RT,DS(RA) -> src_reg1 = RA, offset = DS, dst_reg1 = RT
* X form: ins RT,RA,RB -> src_reg1 = RA, src_reg2 = RB, dst_reg1 = RT
*/
void get_powerpc_regs(u32 raw_insn, int is_source,
struct annotated_op_loc *op_loc)
{
if (is_source)
op_loc->reg1 = get_source_reg(raw_insn);
else
op_loc->reg1 = get_target_reg(raw_insn);
if (op_loc->multi_regs)
op_loc->reg2 = PPC_RB(raw_insn);
/* TODO: Implement offset handling for X Form */
if ((op_loc->mem_ref) && (PPC_OP(raw_insn) != 31))
op_loc->offset = get_offset_opcode(raw_insn);
}