apple: G5P render and compute for J71t with the device's own firmware

boot/initramfs/root/init

@@ -89,6 +89,32 @@ mkdir -p /newroot
 mount ${fstype:+-t "$fstype"} -o "$mode${flags:+,$flags}" "$device" /newroot || stop "could not mount $device"
 [ -x "/newroot$init" ] || [ -L "/newroot$init" ] || stop "the root has no $init"
 
+# Preserve the running boot's *pristine* tree before any package update can
+# replace /boot or same-release module assets. The matching initrd embeds cold
+# DTBs; warm boots name their retained stage instead. Never infer it by uname.
+mkdir -p /run /newroot/run
+mount -t tmpfs -o mode=0755,nosuid,nodev tmpfs /run
+mkdir -p /run/orchard-kexec
+warm_pristine=
+for argument in $(cat /proc/cmdline); do
+    case "$argument" in orchard_warm.dtb=*) warm_pristine=${argument#orchard_warm.dtb=} ;; esac
+done
+if [ -n "$warm_pristine" ]; then
+    case "$warm_pristine" in
+        /var/tmp/orchard-warm.*/pristine.dtb)
+            case "$warm_pristine" in *..*) stop 'invalid warm DT provenance' ;; esac
+            cp "/newroot$warm_pristine" /run/orchard-kexec/pristine.dtb || stop 'missing warm pristine DT' ;;
+        *) stop 'invalid warm DT provenance' ;;
+    esac
+elif [ -f /etc/orchard/pristine-map ]; then
+    board=$(tr '\000' '\n' < /proc/device-tree/compatible | head -1)
+    while read compatible file; do
+        [ "$compatible" != "$board" ] || cp "/etc/orchard/dtbs/$file" /run/orchard-kexec/pristine.dtb
+done < /etc/orchard/pristine-map
+fi
+cat /proc/sys/kernel/random/boot_id > /run/orchard-kexec/boot-id
+mount --move /run /newroot/run || stop 'cannot retain boot provenance'
+
 # USB for the host: network (usb0) and a serial console (ttyGS0), named after
 # the system, so `orchard devices` sees it. What runs on them is the system's.
 usb_gadget() {

boot/m1n1/README.md

@@ -28,3 +28,16 @@ gives the same tree as Hoolock's tip before updating `sources.toml`.
 
 Scratch stays in ignored `boot/m1n1/.work/<device>/`. `--resume` reuses it only
 if the recorded patch set is unchanged.
+
+## Resident PSCI on A7-A9
+
+Orchard patch 0015 adds the resident EL3 PSCI monitor (CPU_ON, CPU_OFF,
+AFFINITY_INFO); 0016-0019 make it the default whenever m1n1 is entered at EL3
+and add SYSTEM_RESET (warm reboot back into m1n1, which boots the default BLS
+entry with the last launch's DTB) and SYSTEM_OFF (halt). Any PSCI-aware
+kernel reboots, powers off and kexecs through its ordinary paths; m1n1 takes
+IPI-stopped CPUs back by trapping EL1 WFI/WFE to EL3. EL1/EL2 entries keep
+the spin table. Payload variables (append to `m1n1.bin`, e.g. with
+`psci-loader`): `psci=0` turns PSCI off, `psci_reset=0` keeps only the CPU
+lifecycle (no WFI/WFE traps), `psci_reset=proxy` stops in the proxy after a
+reset. 0020 marks retained hardware in the device tree after a re-entry.