From: Tobias Heider <me@tobhe.de>
Date: Sun, 12 Feb 2023 01:23:08 +0100
Subject: debian: Add initramfs-tools implementation for cpio firmware loading

- Add initramfs hooks and boot scripts to extract and mount firmware
- Add update-m1n1 kernel hook
- Add install-initramfs make target
- busybox mount doesn't support PARTUUID= so use /dev/disk/by-partuuid
---
 Makefile                            | 15 ++++++++-
 functions.sh                        |  4 +--
 initramfs/hooks/asahi               | 39 ++++++++++++++++++++++++
 initramfs/kernel/zz-update-m1n1     | 26 ++++++++++++++++
 initramfs/modules                   | 43 ++++++++++++++++++++++++++
 initramfs/scripts/init-bottom/asahi | 19 ++++++++++++
 initramfs/scripts/init-top/asahi    | 61 +++++++++++++++++++++++++++++++++++++
 7 files changed, 204 insertions(+), 3 deletions(-)
 create mode 100644 initramfs/hooks/asahi
 create mode 100644 initramfs/kernel/zz-update-m1n1
 create mode 100644 initramfs/modules
 create mode 100644 initramfs/scripts/init-bottom/asahi
 create mode 100644 initramfs/scripts/init-top/asahi

diff --git a/Makefile b/Makefile
index aca6667..3d9b04e 100644
--- a/Makefile
+++ b/Makefile
@@ -54,6 +54,19 @@ install-macsmc-battery: install
 	install -m0755 -t $(DESTDIR)$(SYSTEMD_UNIT_DIR) macsmc-battery/systemd/macsmc-battery-charge-control-end-threshold.service
 	install -m0644 -t $(DESTDIR)$(UDEV_RULES_DIR) macsmc-battery/udev/93-macsmc-battery-charge-control.rules
 
+install-initramfs: install
+	install -d $(DESTDIR)/etc/kernel/postinst.d/
+	install -m0755 -t $(DESTDIR)/etc/kernel/postinst.d/ initramfs/kernel/zz-update-m1n1
+	install -d $(DESTDIR)/etc/kernel/postrm.d/
+	install -m0755 -t $(DESTDIR)/etc/kernel/postrm.d/ initramfs/kernel/zz-update-m1n1
+	install -d $(DESTDIR)$(PREFIX)/share/initramfs-tools/hooks/
+	install -m0755 -t $(DESTDIR)$(PREFIX)/share/initramfs-tools/hooks/ initramfs/hooks/asahi
+	install -d $(DESTDIR)$(PREFIX)/share/initramfs-tools/scripts/init-top
+	install -m0755 -t $(DESTDIR)$(PREFIX)/share/initramfs-tools/scripts/init-top initramfs/scripts/init-top/asahi
+	install -d $(DESTDIR)$(PREFIX)/share/initramfs-tools/scripts/init-bottom
+	install -m0755 -t $(DESTDIR)$(PREFIX)/share/initramfs-tools/scripts/init-bottom initramfs/scripts/init-bottom/asahi
+	install -m0644 -t $(DESTDIR)$(PREFIX)/share/asahi-scripts initramfs/modules
+
 install-arch: install install-mkinitcpio install-macsmc-battery
 	install -m0755 -t $(DESTDIR)$(BIN_DIR)/ $(BUILD_ARCH_SCRIPTS)
 	install -dD $(DESTDIR)$(PREFIX)/lib/systemd/system
@@ -66,7 +79,7 @@ install-arch: install install-mkinitcpio install-macsmc-battery
 
 install-fedora: install install-dracut install-macsmc-battery
 
-install-debian: install install-macsmc-battery
+install-debian: install install-macsmc-battery install-initramfs
 
 uninstall:
 	rm -f $(addprefix $(DESTDIR)$(BIN_DIR)/,$(SCRIPTS))
diff --git a/functions.sh b/functions.sh
index fd400ff..ccb3ed2 100644
--- a/functions.sh
+++ b/functions.sh
@@ -43,7 +43,7 @@ mount_sys_esp() {
         mount --bind "$bootmnt" "$mountpoint"
         warn "System ESP not identified in device tree, using $bootmnt"
     else
-        mount "PARTUUID=$esp_uuid" "$mountpoint"
+        mount -t vfat "/dev/disk/by-partuuid/$esp_uuid" "$mountpoint"
     fi
     dev="$(grep "$mountpoint" /proc/mounts | cut -d" " -f1)"
     info "Mounted System ESP $dev at $mountpoint"
@@ -72,7 +72,7 @@ mount_boot_esp() {
             return 1
         fi
 
-        mount "PARTUUID=$esp_uuid" "$mountpoint"
+        mount -t vfat "/dev/disk/by-partuuid/$esp_uuid" "$mountpoint"
     fi
     info "Mounted Boot ESP at $mountpoint"
 }
diff --git a/initramfs/hooks/asahi b/initramfs/hooks/asahi
new file mode 100644
index 0000000..dd44b59
--- /dev/null
+++ b/initramfs/hooks/asahi
@@ -0,0 +1,39 @@
+#!/bin/sh
+
+PREREQ=""
+
+prereqs()
+{
+        echo "$PREREQ"
+}
+
+case $1 in
+prereqs)
+        prereqs
+        exit 0
+        ;;
+esac
+
+# Hooks for loading asahi modules and firmware
+
+. /usr/share/initramfs-tools/hook-functions
+
+mkdir -p "${DESTDIR}/lib/firmware"
+mkdir -p "${DESTDIR}/usr/share/asahi-scripts"
+cp -r /usr/share/asahi-scripts/* "${DESTDIR}/usr/share/asahi-scripts"
+
+# Debian
+copy_exec /usr/bin/cpio
+copy_exec /usr/bin/cut
+copy_exec /usr/bin/dirname
+copy_exec /usr/bin/grep
+copy_exec /usr/bin/mkdir
+copy_exec /usr/bin/seq
+copy_exec /usr/bin/sleep
+copy_exec /usr/sbin/modprobe
+
+manual_add_modules vfat
+manual_add_modules nls_ascii
+manual_add_modules nls_cp437
+
+add_modules_from_file /usr/share/asahi-scripts/modules
diff --git a/initramfs/kernel/zz-update-m1n1 b/initramfs/kernel/zz-update-m1n1
new file mode 100644
index 0000000..f5853c3
--- /dev/null
+++ b/initramfs/kernel/zz-update-m1n1
@@ -0,0 +1,26 @@
+#! /bin/sh
+set -e
+
+which update-m1n1 >/dev/null 2>&1 || exit 0
+
+if [ ! -e /usr/lib/m1n1/m1n1.bin ] && [ -e /usr/lib/m1n1/boot.bin ]; then
+	# looks like glanzmanns m1n1 package, not debians.
+	exit 0
+fi
+
+set -- $DEB_MAINT_PARAMS
+mode="${1#\'}"
+mode="${mode%\'}"
+case $0:$mode in
+    # Only run on postinst configure and postrm remove, to avoid wasting
+    # time by calling update-grub multiple times on upgrade and removal.
+    # Also run if we have no DEB_MAINT_PARAMS, in order to work with old
+    # kernel packages.
+    */postinst.d/*:|*/postinst.d/*:configure|*/postrm.d/*:|*/postrm.d/*:remove)
+	if [ -e /boot/efi/m1n1/boot.bin ]; then
+		exec update-m1n1
+	fi
+	;;
+esac
+
+exit 0
diff --git a/initramfs/modules b/initramfs/modules
new file mode 100644
index 0000000..6cbe56c
--- /dev/null
+++ b/initramfs/modules
@@ -0,0 +1,43 @@
+# For NVMe & SMC
+apple-mailbox
+# For NVMe
+nvme_apple
+# For USB and HID
+pinctrl-apple-gpio
+# SMC core
+macsmc
+macsmc-rtkit
+# For USB
+i2c-apple
+i2c-pasemi-platform
+tps6598x
+apple-dart
+dwc3
+dwc3-of-simple
+nvmem-apple-efuses
+phy-apple-atc
+xhci-pci
+xhci-plat-hcd
+pcie-apple
+gpio_macsmc
+# For HID
+spi-apple
+spi-hid-apple
+spi-hid-apple-of
+# For RTC
+rtc-macsmc
+spmi-apple-controller
+apple_nvmem_spmi
+# For RTC, obsoleted by linux 6.15,
+# drop in future release
+simple-mfd-spmi
+nvmem_spmi_mfd
+# For MTP HID
+apple-dockchannel
+dockchannel-hid
+apple-rtkit-helper
+# For DP / HDMI audio
+apple-sio
+# For DPTX and HDMI displays
+mux-apple-display-crossbar
+phy-apple-dptx
diff --git a/initramfs/scripts/init-bottom/asahi b/initramfs/scripts/init-bottom/asahi
new file mode 100644
index 0000000..cac593b
--- /dev/null
+++ b/initramfs/scripts/init-bottom/asahi
@@ -0,0 +1,19 @@
+#!/bin/sh
+
+PREREQ=""
+prereqs()
+{
+        echo "$PREREQ"
+}
+case $1 in
+# get pre-requisites
+prereqs)
+        prereqs
+        exit 0
+        ;;
+esac
+
+. /scripts/functions
+
+mount -t tmpfs -o mode=0755 vendorfw "${rootmnt}"/lib/firmware/vendor
+cp -a /vendorfw/* /vendorfw/.vendorfw.manifest "${rootmnt}"/lib/firmware/vendor
diff --git a/initramfs/scripts/init-top/asahi b/initramfs/scripts/init-top/asahi
new file mode 100644
index 0000000..2044e32
--- /dev/null
+++ b/initramfs/scripts/init-top/asahi
@@ -0,0 +1,61 @@
+#!/bin/sh
+
+PREREQ="udev"
+prereqs()
+{
+        echo "$PREREQ"
+}
+case $1 in
+# get pre-requisites
+prereqs)
+        prereqs
+        exit 0
+        ;;
+esac
+
+. /scripts/functions
+
+if [ -e /lib/firmware/vendor ]; then
+	log_failure_msg "Vendor firmware was loaded by the bootloader"
+	return 1
+fi
+
+if [ ! -e /proc/device-tree/chosen/asahi,efi-system-partition ]; then
+	log_failure_msg "Missing asahi,efi-system-partition variable, firmware will not be loaded!"
+	return 1
+fi
+
+log_success_msg "Load NVME modules"
+modprobe apple-mailbox
+modprobe nvme-apple
+modprobe xhci-plat-hcd
+
+for i in $(seq 0 50); do
+[ -e /sys/bus/platform/drivers/nvme-apple/*.nvme/nvme/nvme*/nvme*n1/ ] && break
+	sleep 0.1
+done
+
+if [ ! -e /sys/bus/platform/drivers/nvme-apple/*.nvme/nvme/nvme*/nvme*n1/ ]; then
+err "Timed out waiting for NVMe device"
+	return 1
+fi
+
+# If the above exists, hopefully the /dev device exists and this will work
+VENDORFW="/run/.system-efi/vendorfw/"
+
+(
+	. /usr/share/asahi-scripts/functions.sh
+	mount_sys_esp /run/.system-efi
+)
+
+if [ ! -e "$VENDORFW/firmware.cpio" ]; then
+	log_failure_msg "Vendor firmware not available in ESP!"
+	umount /run/.system-efi
+	return 1
+fi
+
+
+( cd /; cpio -i < "$VENDORFW/firmware.cpio" )
+umount /run/.system-efi
+
+log_success_msg "Asahi: Vendor firmware unpacked successfully"