planet-geminipda: add support for Planet Gemini PDA based on earlier work

device/device-planet-geminipda/10-geminipda-loopback-device.sh

+#!/bin/sh
+. /etc/deviceinfo
+. ./init_functions.sh
+
+mount_loopback_device() {
+	loopback_img=postmarketOS.img
+	partitions="/dev/mmcblk0p29 /dev/mmcblk0p30 /dev/mmcblk0p31"
+
+	mkdir /tmpmnt
+	for part in $partitions; do
+		mount -o ro $part /tmpmnt
+
+		if [ -f "/tmpmnt/$loopback_img" ]; then
+			mount -o remount,rw /tmpmnt
+			loopback_device=$(losetup -f)
+			losetup $loopback_device "/tmpmnt/$loopback_img"
+			kpartx -afs $loopback_device
+			return 0
+		fi
+
+		umount /tmpmnt
+	done
+}
+
+mount_loopback_device

device/device-planet-geminipda/20-fbdev.conf

+Section "Device"
+    Identifier      "Framebuffer device"
+    Driver          "fbdev"
+    Option          "Rotate" "CCW"
+EndSection

device/device-planet-geminipda/40-hwcomposer.conf

+Section "Device"
+    Identifier      "HWComposer device"
+    Driver          "hwcomposer"
+    Option          "Rotate" "CCW"
+EndSection

device/device-planet-geminipda/APKBUILD

+# Reference: <https://postmarketos.org/devicepkg>
+pkgname="device-planet-geminipda"
+pkgdesc="Gemini PDA"
+pkgver=0.1
+pkgrel=0
+url="https://postmarketos.org"
+license="MIT"
+arch="aarch64"
+options="!check !archcheck"
+depends="postmarketos-base linux-planet-geminipda mkbootimg"
+makedepends="devicepkg-dev"
+source="deviceinfo
+	10-geminipda-loopback-device.sh
+	20-fbdev.conf
+	40-hwcomposer.conf"
+subpackages="$pkgname-hybris"
+
+build() {
+	devicepkg_build $startdir $pkgname
+}
+
+package() {
+	devicepkg_package $startdir $pkgname
+
+	install -Dm644 "$srcdir"/10-geminipda-loopback-device.sh \
+		"$pkgdir"/etc/postmarketos-mkinitfs/hooks/10-geminipda-loopback-device.sh
+
+	install -Dm644 "$srcdir"/20-fbdev.conf \
+		"$subpkgdir"/etc/X11/xorg.conf.d/20-fbdev.conf
+}
+
+hybris() {
+	depends="lxc-android
+		libhybris-7.1 libhybris-egl libhybris-gles libhybris-libwayland-egl
+		xf86-video-hwcomposer xf86-video-hwcomposer-7.1"
+
+	install -Dm644 "$srcdir"/40-hwcomposer.conf \
+		"$subpkgdir"/etc/X11/xorg.conf.d/40-hwcomposer.conf
+}
+
+sha512sums="273a79f621df7d40f4b10e4845fbd7147b060e5b2eadd3e5c93d25b5cc029b0e4dfe32fd0f1f827b2512ee7da942aa4186d872e4174e90dd08370dfae312784d  deviceinfo
+a8b6623a0a8bea1ab3e28582f203426e42aed477be9ca1d6147d090f9f9d080a69c262a47f9dd5cd8ce99a9bf64912d902dc881f97967873466ebe73d9bba587  10-geminipda-loopback-device.sh
+07bda3435dffec7f8e8e158266cb619fb41c6b04a49a605e76fa88bc33be3cb27fdc54c8664be0738bab2c7a8054ce3d7563036323bf04762dcf735064ac10a2  20-fbdev.conf
+785bd225025fb73900dca06b70b2d62fdf4145d1c035b1b03fb0f82a10cc09eff63ec551ead4e1ee780a6b6f348c3f82fd068f6efa6f4e34205600d752f38913  40-hwcomposer.conf"

device/device-planet-geminipda/deviceinfo

+# Reference: <https://postmarketos.org/deviceinfo>
+# Please use double quotes only. You can source this file in shell scripts.
+
+deviceinfo_format_version="0"
+deviceinfo_name="Planet Gemini PDA"
+deviceinfo_manufacturer="Planet"
+deviceinfo_codename="planet-geminipda"
+deviceinfo_date=""
+deviceinfo_dtb=""
+deviceinfo_modules_initfs=""
+deviceinfo_arch="aarch64"
+
+# Device related
+deviceinfo_keyboard="true"
+deviceinfo_external_storage="true"
+deviceinfo_screen_width="1080"
+deviceinfo_screen_height="2160"
+deviceinfo_dev_touchscreen=""
+deviceinfo_dev_touchscreen_calibration=""
+deviceinfo_dev_keyboard=""
+
+# Bootloader related
+deviceinfo_flash_method="fastboot"
+deviceinfo_kernel_cmdline="bootopt=64S3,32N2,64N2 androidboot.selinux=permissive buildvariant=userdebug selinux=1"
+deviceinfo_generate_bootimg="true"
+deviceinfo_bootimg_qcdt="false"
+deviceinfo_flash_offset_base="0x40080000"
+deviceinfo_flash_offset_kernel="0x00000000"
+deviceinfo_flash_offset_ramdisk="0x04f80000"
+deviceinfo_flash_offset_second="0x00e80000"
+deviceinfo_flash_offset_tags="0x03f80000"
+deviceinfo_flash_pagesize="2048"

device/linux-planet-geminipda/APKBUILD

+# Reference: <https://postmarketos.org/vendorkernel>
+# Kernel config based on: arch/arm64/configs/aeon6797_6m_n_halium_defconfig
+
+pkgname="linux-planet-geminipda"
+pkgver=3.18.41
+pkgrel=0
+pkgdesc="Gemini PDA kernel fork"
+arch="aarch64"
+_carch="arm64"
+_flavor="planet-geminipda"
+url="https://kernel.org"
+license="GPL-2.0-only"
+options="!strip !check !tracedeps"
+makedepends="perl sed installkernel bash gmp-dev bc linux-headers elfutils-dev devicepkg-dev gcc6 python"
+
+# Compiler: GCC 6 (doesn't boot when compiled with newer versions)
+if [ "${CC:0:5}" != "gcc6-" ]; then
+	CC="gcc6-$CC"
+	HOSTCC="gcc6-gcc"
+	CROSS_COMPILE="gcc6-$CROSS_COMPILE"
+fi
+
+# Source
+_repository="gemini-linux-kernel-3.18"
+_commit="bf7daa4483d5dce94c9d478fc28854f5978d60da"
+_config="config-${_flavor}.${arch}"
+source="
+	$pkgname-$_commit.tar.gz::https://github.com/gemian/${_repository}/archive/${_commit}.tar.gz
+	$_config
+"
+builddir="$srcdir/${_repository}-${_commit}"
+
+prepare() {
+	default_prepare
+
+	# support newer GCC versions
+	cp -v "/usr/share/devicepkg-dev/compiler-gcc.h" "$builddir/include/linux/"
+
+	# Remove -Werror from all makefiles
+	makefiles="$(find "$builddir" -type f -name Makefile)
+		$(find "$builddir" -type f -name Kbuild)"
+	for i in $makefiles; do
+		sed -i 's/-Werror-/-W/g' "$i"
+		sed -i 's/-Werror//g' "$i"
+	done
+
+	# Device kernel must(!) be build out-of-tree to avoid include errors
+	mkdir -p "$builddir"/KERNEL_OBJ
+
+	# Prepare kernel config ('yes ""' for kernels lacking olddefconfig)
+	cp "$srcdir"/$_config "$builddir"/KERNEL_OBJ/.config
+	yes "" | make -C "$builddir" ARCH="$_carch" HOSTCC="$HOSTCC" \
+		O="$builddir"/KERNEL_OBJ oldconfig
+}
+
+build() {
+	unset LDFLAGS
+	make ARCH="$_carch" CC="${CC:-gcc}" \
+		KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-postmarketOS" \
+		O="$builddir"/KERNEL_OBJ
+}
+
+package() {
+	# kernel.release
+	install -D "$builddir/KERNEL_OBJ/include/config/kernel.release" \
+		"$pkgdir/usr/share/kernel/$_flavor/kernel.release"
+
+	# zImage (find the right one)
+	cd "$builddir/KERNEL_OBJ/arch/$_carch/boot"
+	_target="$pkgdir/boot/vmlinuz-$_flavor"
+	for _zimg in zImage-dtb Image.gz-dtb *zImage Image; do
+		[ -e "$_zimg" ] || continue
+		msg "zImage found: $_zimg"
+		install -Dm644 "$_zimg" "$_target"
+		break
+	done
+	if ! [ -e "$_target" ]; then
+		error "Could not find zImage in $PWD!"
+		return 1
+	fi
+}
+
+sha512sums="84579ba59ada9166794ec02843616049128c199f9c68b519d3e33056822a22d12921b6589ff058d08e580e877a227a124f999f041e29b6d81a8fde7ce7480b11  linux-planet-geminipda-bf7daa4483d5dce94c9d478fc28854f5978d60da.tar.gz
+019e2cb30c6d61b37c5c6c5f583da5be42e37bb7eb695bba4dc30dfe91196d3f20ba57ae3ac6931f9ea4cbf4a7c2cdd95f603191e387c3e292b667049a4e9876  config-planet-geminipda.aarch64"

device/linux-planet-geminipda/compiler-gcc6.h

+// SOURCE:
+// https://github.com/NextThingCo/CHIP-u-boot/issues/10#issuecomment-287515505
+
+#ifndef __LINUX_COMPILER_H
+#error "Please don't include <linux/compiler-gcc6.h> directly, include <linux/compiler.h> instead."
+#endif
+
+#define __used				__attribute__((__used__))
+#define __must_check			__attribute__((warn_unused_result))
+#define __compiler_offsetof(a, b)	__builtin_offsetof(a, b)
+
+/* Mark functions as cold. gcc will assume any path leading to a call
+   to them will be unlikely.  This means a lot of manual unlikely()s
+   are unnecessary now for any paths leading to the usual suspects
+   like BUG(), printk(), panic() etc. [but let's keep them for now for
+   older compilers]
+
+   Early snapshots of gcc 4.3 don't support this and we can't detect this
+   in the preprocessor, but we can live with this because they're unreleased.
+   Maketime probing would be overkill here.
+
+   gcc also has a __attribute__((__hot__)) to move hot functions into
+   a special section, but I don't see any sense in this right now in
+   the kernel context */
+#define __cold			__attribute__((__cold__))
+
+#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
+
+#ifndef __CHECKER__
+# define __compiletime_warning(message) __attribute__((warning(message)))
+# define __compiletime_error(message) __attribute__((error(message)))
+#endif /* __CHECKER__ */
+
+/*
+ * Mark a position in code as unreachable.  This can be used to
+ * suppress control flow warnings after asm blocks that transfer
+ * control elsewhere.
+ *
+ * Early snapshots of gcc 4.5 don't support this and we can't detect
+ * this in the preprocessor, but we can live with this because they're
+ * unreleased.  Really, we need to have autoconf for the kernel.
+ */
+#define unreachable() __builtin_unreachable()
+
+/* Mark a function definition as prohibited from being cloned. */
+#define __noclone	__attribute__((__noclone__))
+
+/*
+ * Tell the optimizer that something else uses this function or variable.
+ */
+#define __visible __attribute__((externally_visible))
+
+/*
+ * GCC 'asm goto' miscompiles certain code sequences:
+ *
+ *   http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
+ *
+ * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
+ *
+ * (asm goto is automatically volatile - the naming reflects this.)
+ */
+#define asm_volatile_goto(x...)	do { asm goto(x); asm (""); } while (0)
+
+#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP
+#define __HAVE_BUILTIN_BSWAP32__
+#define __HAVE_BUILTIN_BSWAP64__
+#define __HAVE_BUILTIN_BSWAP16__
+#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
+