flash_fp_mcu: add options for flash read/write protection

Defaults to disabling both read and write flash protection, but you can
disable either or both with these new commandline flags. This is
primarily going to be used for testing (e.g., RDP1 to RDP0 causing mass
erase).

BRANCH=nocturne,nami
BUG=chromium:890059
TEST=dut-control fw_wp_state:force_off
     flash_fp_mcu /opt/google/biod/fw/nami_fp_v2.2.133-31dfe0b1a.bin
     ectool --name=cros_fp version
TEST=flash_fp_mcu -r /tmp/rb.bin
     diff /tmp/rb.in /opt/google/biod/fw/nami_fp_v2.2.133-31dfe0b1a.bin
TEST=dut-control fw_wp_state:force_on
     ectool --name=cros_fp flashprotect enable
     ectool --name=cros_fp reboot_ec
     dut-control fw_wp_state:force_off
     flash_fp_mcu -r --noremove_flash_read_protect /tmp/rb.bin
     echo $? => 1
     ectool --name=cros_fp version => works
     flash_fp_mcu -r /tmp/rb-erase.bin
     hexdump /tmp/rb-erase.bin => all 0xff

Change-Id: I42f7daf08dcf229a4980c88a24e6882be7c0e8d6
Signed-off-by: Tom Hughes <tomhughes@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1474743

1 files changed, 29 insertions, 3 deletions

diff --git a/util/flash_fp_mcu b/util/flash_fp_mcu
index 6a23aa691c..76965470a9 100644
--- a/util/flash_fp_mcu
+++ b/util/flash_fp_mcu
@@ -6,6 +6,12 @@
 . /usr/share/misc/shflags
 
 DEFINE_boolean 'read' "${FLAGS_FALSE}" 'Read instead of write' 'r'
+# Both flash read and write protection are removed by default, but you
+# can optionally enable them (for testing purposes).
+DEFINE_boolean 'remove_flash_read_protect' "${FLAGS_TRUE}" \
+  'Remove flash read protection while performing command' 'U'
+DEFINE_boolean 'remove_flash_write_protect' "${FLAGS_TRUE}" \
+  'Remove flash write protection while performing command' 'u'
 FLAGS_HELP="Usage: ${0} [flags] ec.bin"
 
 # Process commandline flags
@@ -111,10 +117,20 @@ flash_fp_mcu_stm32() {
   local file="${5}"
   local spiid
 
-  local STM32MON_READ_FLAGS=" -U -u -p -s ${spidev} -r"
-  local STM32MON_WRITE_FLAGS="-U -u -p -s ${spidev} -e -w"
+  local STM32MON_READ_FLAGS=" -p -s ${spidev} -r"
+  local STM32MON_WRITE_FLAGS="-p -s ${spidev} -e -w"
   local stm32mon_flags=""
 
+  if [[ "${FLAGS_remove_flash_write_protect}" -eq "${FLAGS_TRUE}" ]]; then
+    STM32MON_READ_FLAGS=" -u ${STM32MON_READ_FLAGS}"
+    STM32MON_WRITE_FLAGS="-u ${STM32MON_WRITE_FLAGS}"
+  fi
+
+  if [[ "${FLAGS_remove_flash_read_protect}" -eq "${FLAGS_TRUE}" ]]; then
+    STM32MON_READ_FLAGS=" -U ${STM32MON_READ_FLAGS}"
+    STM32MON_WRITE_FLAGS="-U ${STM32MON_WRITE_FLAGS}"
+  fi
+
   if [[ "${FLAGS_read}" -eq "${FLAGS_TRUE}" ]]; then
     if [[ -e "${file}" ]]; then
       echo "Output file already exists: ${file}"
@@ -168,7 +184,12 @@ flash_fp_mcu_stm32() {
   echo 1 > "/sys/class/gpio/gpio${gpio_nrst}/value"
   echo "in" > "/sys/class/gpio/gpio${gpio_nrst}/direction"
 
-  stm32mon ${stm32mon_flags} "${file}"
+  # Print out the actual underlying command we're running and run it
+  local cmd="stm32mon ${stm32mon_flags} ${file}"
+  echo "${cmd}"
+  ${cmd}
+
+  local cmd_exit_status=$?
 
   # unload spidev
   echo "${spiid}" > /sys/bus/spi/drivers/spidev/unbind
@@ -193,6 +214,11 @@ flash_fp_mcu_stm32() {
   if [[ -n "${gpio_pwren}" ]]; then
     echo "${gpio_pwren}" > /sys/class/gpio/unexport
   fi
+
+  if [[ "${cmd_exit_status}" -ne 0 ]]; then
+    exit 1
+  fi
+
   # Test it
   ectool --name=cros_fp version
 }