/*
* Copyright (c) 2008 Jiri Svoboda
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup debug
* @{
*/
/** @file
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <sys/types.h>
#include <errno.h>
#include <udebug.h>
#include "../../../cons.h"
#include "../../../main.h"
#include "../../../breakpoint.h"
#include "../../../include/arch.h"
#define OPCODE_BREAK 0x0000000d
static istate_t istate;
typedef enum {
/* Branches (conditional) */
OP_BCzF,
OP_BCzFL,
OP_BCzT,
OP_BCzTL,
OP_BEQ,
OP_BEQL,
OP_BGEZ,
OP_BGEZAL,
OP_BGEZALL,
OP_BGEZL,
OP_BGTZ,
OP_BGTZL,
OP_BLEZ,
OP_BLEZL,
OP_BLTZ,
OP_BLTZAL,
OP_BLTZALL,
OP_BLTZL,
OP_BNE,
OP_BNEL,
/* Jumps (unconditional) */
OP_J,
OP_JAL,
OP_JALR,
OP_JR
} op_t;
typedef struct {
uint32_t mask;
uint32_t value;
op_t op;
} instr_desc_t;
static instr_desc_t decoding_table[] = {
{ 0xf3ff0000, 0x41000000, OP_BCzF },
{ 0xf3ff0000, 0x41020000, OP_BCzFL },
{ 0xf3ff0000, 0x41010000, OP_BCzT },
{ 0xf3ff0000, 0x41030000, OP_BCzTL },
{ 0xfc000000, 0x10000000, OP_BEQ },
{ 0xfc000000, 0x50000000, OP_BEQL },
{ 0xfc1f0000, 0x04010000, OP_BGEZ },
{ 0xfc1f0000, 0x04110000, OP_BGEZAL },
{ 0xfc1f0000, 0x04130000, OP_BGEZALL },
{ 0xfc1f0000, 0x04030000, OP_BGEZL },
{ 0xfc1f0000, 0x1c000000, OP_BGTZ },
{ 0xfc1f0000, 0x5c000000, OP_BGTZL },
{ 0xfc1f0000, 0x18000000, OP_BLEZ },
{ 0xfc1f0000, 0x58000000, OP_BLEZL },
{ 0xfc1f0000, 0x04000000, OP_BLTZ },
{ 0xfc1f0000, 0x04100000, OP_BLTZAL },
{ 0xfc1f0000, 0x04120000, OP_BLTZALL },
{ 0xfc1f0000, 0x04020000, OP_BLTZL },
{ 0xfc000000, 0x14000000, OP_BNE },
{ 0xfc000000, 0x54000000, OP_BNEL },
{ 0xfc000000, 0x08000000, OP_J },
{ 0xfc000000, 0x0c000000, OP_JAL },
{ 0xfc1f07ff, 0x00000009, OP_JALR },
{ 0xfc1fffff, 0x00000008, OP_JR },
{ 0, 0, -1 }
};
void arch_dthread_initialize(dthread_t *dt)
{
dt->arch.singlestep = false;
bstore_initialize(&dt->arch.cur);
bstore_initialize(&dt->arch.next[0]);
bstore_initialize(&dt->arch.next[1]);
}
int arch_breakpoint_set(breakpoint_t *b)
{
bstore_initialize(&b->arch.bs);
bstore_initialize(&b->arch.next_bs[0]);
bstore_initialize(&b->arch.next_bs[1]);
return bstore_push(&b->arch.bs, b->addr, OPCODE_BREAK);
}
int arch_breakpoint_remove(breakpoint_t *b)
{
return bstore_pop(&b->arch.bs);
}
static int islot_read(uintptr_t addr, uint32_t *instr)
{
int rc;
rc = udebug_mem_read(app_phone, instr, addr, sizeof(uint32_t));
if (rc != EOK) {
cons_printf("Error reading memory address 0x%zx\n", addr);
}
return rc;
}
static op_t instr_decode(uint32_t instr)
{
instr_desc_t *idesc;
idesc = &decoding_table[0];
while (idesc->op >= 0) {
if ((instr & idesc->mask) == idesc->value)
return idesc->op;
++idesc;
}
return -1;
}
static int get_reg(int reg_no, uint32_t *value)
{
cons_printf("get_reg...\n");
if (reg_no == 0) {
*value = 0;
return 0;
}
/* FIXME: ugly */
*value = ((uint32_t *)&istate)[reg_no - 1];
printf("get_reg ok (0x%08x)\n", *value
);
return 0;
}
/** Get address of the instruction that will be executed after the current one.
*
* Assumptions: addr == PC, *addr is not covered by a BREAK.
*
* @param addr Address of an instruction.
* @param buffer Buffer for storing up to 2 addresses.
* @return Number of stored addresses or negative error code.
*/
static int get_next_addr(uintptr_t addr, uintptr_t *buffer)
{
/* TODO: J[AL]R, branches and delay slots */
uint32_t instr;
int32_t offset;
op_t op;
int rc;
int n;
rc = islot_read(addr, &instr);
if (rc != 0) return rc;
op = instr_decode(instr);
switch (op) {
case OP_BCzF:
case OP_BCzFL:
case OP_BCzT:
case OP_BCzTL:
case OP_BEQ:
case OP_BEQL:
case OP_BGEZ:
case OP_BGEZAL:
case OP_BGEZALL:
case OP_BGEZL:
case OP_BGTZ:
case OP_BGTZL:
case OP_BLEZ:
case OP_BLTZ:
case OP_BLTZAL:
case OP_BLTZALL:
case OP_BLTZL:
case OP_BNE:
case OP_BNEL:
/* Branch */
offset = (int32_t)(int16_t)(instr & 0x0000ffff) << 2;
buffer[0] = (addr + 4) + offset; /* taken */
buffer[1] = addr + 8; /* not taken */
n = 2;
break;
case OP_J:
case OP_JAL:
/* Immediate jump */
buffer[0] =
((addr + 4) & 0xf0000000) |
((instr & 0x03ffffff) << 2);
n = 1;
break;
case OP_JR:
case OP_JALR:
/* Register jump */
rc = get_reg((instr >> 21) & 0x1f, &buffer[0]);
n = 1;
break;
default:
/* Regular instruction */
buffer[0] = addr + 4;
n = 1;
break;
}
return n;
}
static void _ev_breakpoint(thash_t thread_hash)
{
breakpoint_t *b;
dthread_t *dt;
int rc, n_next, i;
uint32_t epc;
uintptr_t brk_addr;
uintptr_t next_addr[2];
uint32_t brkp;
brkp = OPCODE_BREAK;
cons_printf("arch_event_breakpoint\n");
rc = udebug_regs_read(app_phone, thread_hash, &istate);
cons_printf("udebug_regs_read -> %d\n", rc);
epc = istate_get_pc(&istate);
cons_printf("EPC was 0x%08x\n", epc);
brk_addr = epc;
dt = dthread_get();
if (active_bkpt != NULL) {
assert(active_bkpt
->arch.
bs.
address == brk_addr
);
b = active_bkpt;
/* A breakpoint-restoring BRK has been hit */
cons_printf("restoring breakpoint %d\n", b->id);
for (i = 0; i < b->arch.n_next; ++i) {
rc = bstore_pop(&b->arch.next_bs[i]);
if (rc != 0) return;
}
rc = bstore_push(&b->arch.bs, b->addr, OPCODE_BREAK);
if (rc != 0) return;
active_bkpt = NULL;
return;
}
b = breakpoint_find_by_addr(brk_addr);
if (b == NULL) {
cons_printf("Unrecognized breakpoint at 0x%lx\n", brk_addr);
}
/* A breakpoint has been hit */
cons_printf("breakpoint_hit...\n");
breakpoint_hit(b);
/* While in breakpoint_hit(), singlestep was activated */
if (dt->arch.singlestep) return;
cons_printf("move breakpoint\b");
rc = bstore_pop(&b->arch.bs);
if (rc != 0) return;
n_next = get_next_addr(brk_addr, next_addr);
if (n_next < 0) return;
/*
* There could be another breakpoint at next_addr,
* but that's okay. We'll pop the active breakpoint bs
* before doing anything else.
*/
for (i = 0; i < n_next; ++i) {
rc = bstore_push(&b->arch.next_bs[i], next_addr[i],
OPCODE_BREAK);
if (rc != 0) return;
}
b->arch.n_next = n_next;
active_bkpt = b;
b->active = true;
cons_printf("end_hit...\n");
}
static void _ev_singlestep(thash_t thread_hash)
{
dthread_t *dt;
int rc, i;
uint32_t epc;
int brk_addr;
uint32_t brkp;
dt = dthread_get();
brkp = OPCODE_BREAK;
cons_printf("arch_event_breakpoint\n");
rc = udebug_regs_read(app_phone, thread_hash, &istate);
cons_printf("udebug_regs_read -> %d\n", rc);
epc = istate_get_pc(&istate);
cons_printf("EPC was 0x%08x\n", epc);
brk_addr = epc;
if (dt->arch.cur.valid) {
cons_printf("restore breakpoint BREAK\n");
rc = bstore_pop(&dt->arch.cur);
}
cons_printf("\nclear singlestep BREAKs\n");
for (i = 0; i < dt->arch.n_next; ++i) {
rc = bstore_pop(&dt->arch.next[i]);
if (rc != 0) return;
}
dt->arch.singlestep = false;
singlestep_hit();
}
void arch_event_breakpoint(thash_t thread_hash)
{
dthread_t *dt;
dt = dthread_get();
if (dt->arch.singlestep) {
_ev_singlestep(thread_hash);
} else {
_ev_breakpoint(thread_hash);
}
}
void arch_event_trap(dthread_t *dt)
{
/* Unused */
(void)dt;
}
void arch_dump_regs(thash_t thash)
{
/* TODO */
}
void arch_singlestep(dthread_t *dt)
{
int rc, i;
uint32_t epc;
breakpoint_t *b;
uint32_t old_instr;
uintptr_t next_addr[2];
int n_next;
assert(dt
->arch.
singlestep == false);
cons_printf("arch_singlestep(dt)\n");
rc = udebug_regs_read(app_phone, dt->hash, &istate);
cons_printf("udebug_regs_read -> %d\n", rc);
epc = istate_get_pc(&istate);
cons_printf("EPC was 0x%08x\n", epc);
cons_printf("initial set singlestep\n");
b = breakpoint_find_by_addr(epc);
if (b != NULL) {
/* Cover breakpoint with old instruction */
old_instr = b->arch.bs.value;
rc = bstore_push(&dt->arch.cur, epc, old_instr);
if (rc < 0) return;
}
n_next = get_next_addr(epc, next_addr);
if (n_next < 0) return;
/* Cover next instruction(s) with BREAK */
for (i = 0; i < n_next; ++i) {
rc = bstore_push(&dt->arch.next[i], next_addr[i], OPCODE_BREAK);
if (rc != 0) return;
}
dt->arch.n_next = n_next;
dt->arch.singlestep = true;
dthread_resume(dt);
}
/** @}
*/