From 390b4b85e13a1abdc85ddafbe09858ab4341a904 Mon Sep 17 00:00:00 2001
From: Tim Gover <tim.gover@raspberrypi.org>
Date: Fri, 29 Nov 2019 12:45:33 +0000
Subject: [PATCH] vcgencmd: Use cpuinfo instead of otp_dump

On a 64-bit beta kernel a hang in vcgencmd otp_dump was observed
blocking rpi-eeprom-update and apt. Since there is another method
for obtaining the board Revision that should never block use that instead.
---
 rpi-eeprom-update | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/rpi-eeprom-update b/rpi-eeprom-update
index 2f6cabb..9936005 100755
--- a/rpi-eeprom-update
+++ b/rpi-eeprom-update
@@ -224,17 +224,18 @@ getBootloaderUpdateVersion() {
 }
 
 checkDependencies() {
-   if ! command -v vcgencmd  > /dev/null; then
-      die "vcgencmd not found. On Debian, try installing the libraspberrypi-bin package."
-   fi
-
-   CPU_VER="$(vcgencmd otp_dump | grep 30: | cut -c8)"
-
-   if [ "${CPU_VER}" != "3" ]; then
+   rev="$(sed -n '/^Revision/s/^.*: \(.*\)/\1/p' < /proc/cpuinfo)"
+   if [ $(((0x$rev >> 23) & 1)) -ne 0 ] && [ $(((0x$rev >> 12) & 15)) -eq 3 ]; then
+      echo "BCM2711 detected"
+   else
       # Not a BCM2711, no EEPROMs to update.
       exit ${EXIT_SUCCESS}
    fi
 
+   if ! command -v vcgencmd  > /dev/null; then
+      die "vcgencmd not found. On Debian, try installing the libraspberrypi-bin package."
+   fi
+
    if [ ! -d "${FIRMWARE_IMAGE_DIR}" ]; then
       die "EEPROM updates directory ${FIRMWARE_IMAGE_DIR} not found."
    fi