Enhance eMMC provisioning scripts and documentation: add troubleshooting section for device connection issues, update flash script to prevent concurrent runs, and improve logging. Adjust deployment scripts to verify presence of boot files in mass-storage-gadget.

chromium-setup/emmc-provisioning/scripts/build-and-deploy-usbboot-to-host.sh

@@ -41,11 +41,16 @@ rsync -a "$BUILD_DIR/usbboot/rpiboot" "$PROXMOX:/opt/usbboot/"
 # CM4 needs mass-storage-gadget (64-bit); copy whichever exists
 for dir in mass-storage-gadget64 mass-storage-gadget; do
   if [[ -d "$BUILD_DIR/usbboot/$dir" ]]; then
-    rsync -a "$BUILD_DIR/usbboot/$dir" "$PROXMOX:/opt/usbboot/"
+    rsync -a "$BUILD_DIR/usbboot/$dir/" "$PROXMOX:/opt/usbboot/$dir/"
     echo "  Copied $dir/"
   fi
 done
 ssh "$PROXMOX" "chmod +x /opt/usbboot/rpiboot"
 
+# Verify gadget has boot files (rpiboot needs bootfiles.bin or bootcode*.bin)
+if ! ssh "$PROXMOX" "test -f /opt/usbboot/mass-storage-gadget64/bootfiles.bin || test -f /opt/usbboot/mass-storage-gadget64/boot.img" 2>/dev/null; then
+  echo "Warning: mass-storage-gadget64 may be missing boot files. If rpiboot fails with 'No bootcode files found', run: ./populate-gadget-on-host.sh $PROXMOX"
+fi
+
 echo "[$(date -Iseconds)] usbboot deployed to $PROXMOX:/opt/usbboot"
 echo "Ensure the host flash script runs rpiboot with: -d /opt/usbboot/mass-storage-gadget64 (or mass-storage-gadget)."

chromium-setup/emmc-provisioning/scripts/deploy-to-proxmox.sh

@@ -52,6 +52,9 @@ cp "$DEPLOY/host/flash-emmc-on-connect.sh" /opt/cm4-provisioning/
 chmod +x /opt/cm4-provisioning/flash-emmc-on-connect.sh
 cp "$DEPLOY/host/cm4-flash-trigger.sh" /usr/local/bin/
 chmod +x /usr/local/bin/cm4-flash-trigger.sh
+cp "$DEPLOY/host/cm4-flash.service" /etc/systemd/system/
+systemctl daemon-reload
+cp "$DEPLOY/host/89-cm4-boot-mode-permissions.rules" /etc/udev/rules.d/ 2>/dev/null || true
 cp "$DEPLOY/host/90-cm4-boot-mode.rules" /etc/udev/rules.d/
 udevadm control --reload-rules
 log "Host: env and dirs ..."

chromium-setup/emmc-provisioning/scripts/fix-gadget-bootcode-on-host.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+# Run on the Proxmox host (as root) when rpiboot fails with "No 'bootcode' files found".
+# Cause: mass-storage-gadget64/bootfiles.bin is a broken symlink (-> ../firmware/bootfiles.bin).
+# This script removes the symlink and extracts bootcode4.bin from the installed rpiboot binary.
+#
+# On host: bash fix-gadget-bootcode-on-host.sh
+# From your machine: ssh root@10.130.60.224 'bash -s' < scripts/fix-gadget-bootcode-on-host.sh
+
+set -e
+GADGET="${1:-/opt/usbboot/mass-storage-gadget64}"
+RPIBOOT="${2:-/opt/usbboot/rpiboot}"
+
+[[ -d "$GADGET" ]] || { echo "Error: $GADGET not found"; exit 1; }
+[[ -x "$RPIBOOT" ]] || { echo "Error: $RPIBOOT not found"; exit 1; }
+
+# Remove broken bootfiles.bin symlink if present
+if [[ -L "$GADGET/bootfiles.bin" ]] && ! [[ -f "$GADGET/bootfiles.bin" ]]; then
+  rm -f "$GADGET/bootfiles.bin"
+  echo "Removed broken symlink $GADGET/bootfiles.bin"
+fi
+
+# If we already have a valid boot file, done
+if [[ -f "$GADGET/bootcode4.bin" ]] || [[ -f "$GADGET/bootfiles.bin" ]]; then
+  echo "Already has bootcode4.bin or valid bootfiles.bin. OK."
+  exit 0
+fi
+
+# Get .data section file offset and address from ELF
+readelf -S "$RPIBOOT" | grep -q "\.data" || { echo "No .data section"; exit 1; }
+DATA_OFF=$(readelf -S "$RPIBOOT" | awk '/\.data\s/ { print "0x"$5; exit }')
+DATA_ADDR=$(readelf -S "$RPIBOOT" | awk '/\.data\s/ { print "0x"$4; exit }')
+LEN_SYM=$(objdump -t "$RPIBOOT" | awk '/msd_bootcode4_bin_len/ { print $1; exit }')
+BIN_SYM=$(objdump -t "$RPIBOOT" | awk '/msd_bootcode4_bin\s/ { print $1; exit }')
+[[ -n "$LEN_SYM" && -n "$BIN_SYM" ]] || { echo "msd_bootcode4_bin symbols not found in rpiboot"; exit 1; }
+
+LEN_ADDR=$((0x$LEN_SYM))
+BIN_ADDR=$((0x$BIN_SYM))
+LEN_OFF=$((DATA_OFF + LEN_ADDR - DATA_ADDR))
+BIN_OFF=$((DATA_OFF + BIN_ADDR - DATA_ADDR))
+LEN=$(dd if="$RPIBOOT" bs=1 skip=$LEN_OFF count=4 2>/dev/null | od -An -t u4 | tr -d ' ')
+dd if="$RPIBOOT" of="$GADGET/bootcode4.bin" bs=1 skip=$BIN_OFF count=$LEN 2>/dev/null
+echo "Wrote $GADGET/bootcode4.bin ($LEN bytes). Verify: $RPIBOOT -d $GADGET -V"

chromium-setup/emmc-provisioning/scripts/populate-gadget-on-host.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# Populate /opt/usbboot/mass-storage-gadget64 on the Proxmox host (no rpiboot build).
+# Use when rpiboot works but you see "No 'bootcode' files found" — the gadget dir is empty.
+# Usage: ./populate-gadget-on-host.sh [proxmox_host]
+# Example: ./populate-gadget-on-host.sh root@10.130.60.224
+
+set -e
+PROXMOX="${1:-root@10.130.60.224}"
+BUILD_DIR="/tmp/usbboot-gadget-$$"
+cleanup() { rm -rf "$BUILD_DIR"; }
+trap cleanup EXIT
+
+echo "[$(date -Iseconds)] Cloning usbboot to fetch mass-storage-gadget64 ..."
+mkdir -p "$BUILD_DIR"
+git clone --depth=1 https://github.com/raspberrypi/usbboot "$BUILD_DIR/usbboot"
+
+GADGET="$BUILD_DIR/usbboot/mass-storage-gadget64"
+if [[ ! -d "$GADGET" ]]; then
+  echo "Error: mass-storage-gadget64 not found in clone."
+  exit 1
+fi
+# rpiboot needs at least bootfiles.bin or bootcode*.bin
+if [[ ! -f "$GADGET/bootfiles.bin" && ! -f "$GADGET/boot.img" ]]; then
+  echo "Warning: clone has no bootfiles.bin or boot.img. Trying git lfs pull..."
+  (cd "$BUILD_DIR/usbboot" && git lfs pull 2>/dev/null) || true
+fi
+if [[ ! -f "$GADGET/bootfiles.bin" && ! -f "$GADGET/boot.img" ]]; then
+  echo "Error: mass-storage-gadget64 still has no boot files. Install git-lfs and retry, or run build-and-deploy-usbboot-to-host.sh for a full deploy."
+  exit 1
+fi
+
+echo "[$(date -Iseconds)] Syncing mass-storage-gadget64 to $PROXMOX:/opt/usbboot/ ..."
+ssh "$PROXMOX" "mkdir -p /opt/usbboot"
+rsync -a "$GADGET/" "$PROXMOX:/opt/usbboot/mass-storage-gadget64/"
+echo "Done. Verify with: ssh $PROXMOX 'ls -la /opt/usbboot/mass-storage-gadget64/'"