chrome-ec/util/gdbinit

# Copyright 2019 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# This file is intended to be used as a .gdbinit for an EC debugging session.
# It defines some useful functions for analyzing the EC state.
#
# Setup Automatic Import:
# ln -s util/gdbinit .gdbinit
#
# Environment Variables:
# BOARD=[nocturne_fp|bloonchipper|...]
# GDBSERVER=[segger|openocd]
# GDBPORT=[gdb-server-port-number]
#
# Warning, this is a working collection that is not guaranteed to function
# properly on all platforms. The ec-tasks functions is a good example of a
# function that works well on most simple platforms, but may have issues on
# platforms with data cache enabled.
#
# Note, this file must maintain space indention to allow easy copy/paste
# while in active debugging. Using tabs interferes with the embedded python
# during copy/paste.

#####################################################################
# Environment Setup and Initialization                              #
#####################################################################

set verbose on

# Start of python code

# Setup environment and pull in object files for the particular BOARD.
# This requires setting the environment variables mentioned above.
python
import distutils.util
import os

BOARD = os.getenv('BOARD', '')
GDBSERVER = os.getenv('GDBSERVER', 'openocd')
USING_CLION = distutils.util.strtobool(os.getenv('USING_CLION', 'FALSE'))
# BIN_NAME can be changed to be the name of a unit test, such as "sha256"
BIN_NAME = os.getenv('BIN_NAME', 'ec')

BIN_DIR = ''
if BIN_NAME != 'ec':
  BIN_DIR = BIN_NAME

if GDBSERVER == "openocd":
    DEFAULT_GDB_PORT = '3333'
else:
    DEFAULT_GDB_PORT = '2331'

GDBPORT = os.getenv('GDBPORT', DEFAULT_GDB_PORT)

EC_DIR = os.getenv('EC_DIR', os.path.join(os.getenv('HOME'),
                   'chromiumos/src/platform/ec'))

if not os.path.isdir(EC_DIR):
    print('Error - EC_DIR "' + EC_DIR + '" doesn\'t exist. Aborting.')
    gdb.execute('quit')

# Monitor commands must be run after connecting to the remote target
# See https://stackoverflow.com/a/39828850
# https://youtrack.jetbrains.com/issue/CPP-7322
# https://sourceware.org/gdb/onlinedocs/gdb/Hooks.html
post_remote_hook='''
define target hookpost-remote
    echo \ Flashing EC binary
    load {EC_DIR}/build/{BOARD}/{BIN_DIR}/{BIN_NAME}.obj
    echo \ Resetting target
    monitor reset
    echo \ Setting breakpoint on main
    b main
end\n
'''.format(BOARD=BOARD, EC_DIR=EC_DIR, BIN_DIR=BIN_DIR, BIN_NAME=BIN_NAME)

gdb.execute('set $BOARD = "%s"'%BOARD)
gdb.execute('set $GDBSERVER = "%s"'%GDBSERVER)
gdb.execute('set $GDBPORT = "%s"'%GDBPORT)

build = os.path.join(EC_DIR, 'build', BOARD)
if BOARD != "":
    if not os.path.isdir(build):
        print('Error - Build path "' + build + '" doesn\'t exist. Aborting.')
        gdb.execute('quit')

    # When using gdb from CLion, this kills gdb.
    if not USING_CLION:
        gdb.execute('file ' + os.path.join(build, 'ec.obj'))
    gdb.execute('add-symbol-file ' + os.path.join(build, BIN_DIR, 'RO', BIN_NAME + '.RO.elf'))
    gdb.execute('add-symbol-file ' + os.path.join(build, BIN_DIR, 'RW', BIN_NAME + '.RW.elf'))

if GDBSERVER == "openocd":
    gdb.execute('set $GDBSERVER_OPENOCD = 1')
    gdb.execute('set $GDBSERVER_SEGGER = 0')
elif GDBSERVER == "segger":
    gdb.execute('set $GDBSERVER_OPENOCD = 0')
    gdb.execute('set $GDBSERVER_SEGGER = 1')
    gdb.execute(post_remote_hook)
else:
    print('Error - GDBSERVER="' + GDBSERVER + '" is invalid.')
    gdb.execute('quit')

# End of python code
end

# OpenOCD specific config
if $GDBSERVER_OPENOCD
    # Don't auto choose hw/sw breakpoints from memory-map
    set breakpoint auto-hw off
end

# Segger specific config
if $GDBSERVER_SEGGER
    # If enabled, disable flash breakpoints.
    #monitor flash breakpoints = 0
end

# If enabled, force breakpoints to be inserted at all times.
# They will not be reinserted on reconnects.
#set breakpoint always-inserted on

#####################################################################
# Helper Functions                                                  #
#####################################################################

# Usage: reg32 <address> [offset]
# Read a 32 bit register
define reg32
    set $a = $arg0
    if $argc > 1
        set $a += $arg1
    end
    set $v = *((uint32_t *)$a)
    print $v
    print /x $v
    print /t $v
end

# Usage: ec-connect
# Issue the overly long target connect command using the
# specified gdb server port.
define ec-connect
python
    # May want to only use "target remote".
    gdb.execute('target extended-remote :%d'%GDBPORT)
end
end
alias connect = ec-connect

# Usage: ec-reset
# Issue the reset sequence for the debugger to halt on boot.
define ec-reset
    if $GDBSERVER_OPENOCD
        monitor halt
        monitor reset halt
    else
        monitor halt
        monitor reset
    end
end
alias reset = ec-reset

# Usage: ec-tasks
# Prints out information about current EC task set and tries to determine
# if the task's stack has been overrun.
# This function may not work properly if MCU data cache is enabled.
define ec-tasks
    set $taskid_cur = current_task - tasks
    set $id = 0
    set $taskcount = sizeof(tasks)/sizeof(tasks[0])
    printf "Task Ready Name         Events      Time (s)  StkUsed\n"
    while $id < $taskcount
        set $is_ready = (tasks_ready & (1<<$id)) ? 'R' : ' '
        set $unused = (uint32_t)0xdeadd00d
        set $stacksize = tasks_init[$id].stack_size
        set $stackused = $stacksize
        set $s = tasks[$id].stack
        while $s < (uint32_t *)tasks[$id].sp && *$s == $unused
            set $stackused -= sizeof(uint32_t)
            set $s++
        end
        printf "%4d %-5c %-16s %08x %11.6ld  %3d/%3d", $id, $is_ready,  task_names[$id], tasks[$id].events, tasks[$id].runtime, $stackused, tasks_init[$id].stack_size
        if $stackused == $stacksize
            printf "\t [overrun]"
        end
        if $id == $taskid_cur
            printf "\t*"
        end
        printf "\n"
        set $id++
    end
    if $taskid_cur == scratchpad
        printf "Current task is set to scratchpad\n"
    end
end

# Usage: ec-stayro
# Adds magic breakpoint that changes the outcome of the RW signature
# validation step that forces the MCU to stay in the RO section.
# This function needs improvements to not be dependent on line numbers.
define ec-stayro
    break common/rwsig.c:282
    commands
        set evt = 1
        printf "Continuing as RO\n"
        continue
    end
end

# Usage: ec-brexception
# Set breakpoints on EC exception handlers.
define ec-brexception
    break exception_panic
    break bus_fault_handler
    break panic_assert_fail
end