@@ -4,7 +4,7 @@ DESCRIPTION = "These are introductory examples to showcase the use of QEMU to ru
LICENSE = "MIT"
LIC_FILES_CHKSUM = "file://LICENSE;md5=39346640a23c701e4f459e05f56f4449"
-SRCREV = "31b4e5a337018b4a00a7426b0e5ed83b81df30c7"
+SRCREV = "22016ecbb9fb6c5f3a7a06698aea7ff8a701c166"
PV = "0.1+git${SRCPV}"
SRC_URI = "git://github.com/aehs29/baremetal-helloqemu.git;protocol=https;branch=master"
@@ -23,12 +23,15 @@ IMAGE_NAME_SUFFIX ?= ""
inherit baremetal-image
+# startup code for x86 uses NASM syntax
+DEPENDS:qemux86:append = " nasm-native"
+
# These parameters are app specific for this example
# This will be translated automatically to the architecture and
# machine that QEMU uses on OE, e.g. -machine virt -cpu cortex-a57
# but the examples can also be run on other architectures/machines
# such as vexpress-a15 by overriding the setting on the machine.conf
-COMPATIBLE_MACHINE = "qemuarmv5|qemuarm|qemuarm64|qemuriscv64|qemuriscv32"
+COMPATIBLE_MACHINE = "qemuarmv5|qemuarm|qemuarm64|qemuriscv64|qemuriscv32|qemux86|qemux86-64"
BAREMETAL_QEMUARCH ?= ""
BAREMETAL_QEMUARCH:qemuarmv5 = "versatile"
@@ -36,9 +39,15 @@ BAREMETAL_QEMUARCH:qemuarm = "arm"
BAREMETAL_QEMUARCH:qemuarm64 = "aarch64"
BAREMETAL_QEMUARCH:qemuriscv64 = "riscv64"
BAREMETAL_QEMUARCH:qemuriscv32 = "riscv32"
+BAREMETAL_QEMUARCH:qemux86 = "x86"
+BAREMETAL_QEMUARCH:qemux86-64 = "x86-64"
EXTRA_OEMAKE:append = " QEMUARCH=${BAREMETAL_QEMUARCH} V=1"
+# qemux86-64 uses a different Makefile
+do_compile:prepend:qemux86-64(){
+ cd x86-64
+}
# Install binaries on the proper location for baremetal-image to fetch and deploy
do_install(){
@@ -51,3 +60,12 @@ FILES:${PN} += " \
${base_libdir}/firmware/${BAREMETAL_BINNAME}.bin \
${base_libdir}/firmware/${BAREMETAL_BINNAME}.elf \
"
+
+# qemux86-64 boots from iso rather than -kernel, create image to boot from
+do_image:append:qemux86-64(){
+ dd if=/dev/zero of=${B}/build/img.iso bs=1M count=10 status=none
+ dd if=${B}/build/stage1.bin of=${B}/build/img.iso bs=512 count=1 conv=notrunc
+ dd if=${B}/build/stage2.bin of=${B}/build/img.iso bs=512 seek=1 count=64 conv=notrunc
+ dd if=${B}/build/hello_baremetal_x86-64.bin of=${B}/build/img.iso bs=512 seek=65 conv=notrunc
+ install ${B}/build/img.iso ${IMGDEPLOYDIR}/${IMAGE_LINK_NAME}.iso
+}
@@ -86,6 +86,11 @@ QB_DEFAULT_FSTYPE ?= "bin"
QB_DTB ?= ""
QB_OPT_APPEND:append = " -nographic"
+# QEMU x86 requires an .elf kernel to boot rather than a .bin
+QB_DEFAULT_KERNEL:qemux86 ?= "${IMAGE_LINK_NAME}.elf"
+# QEMU x86-64 refuses to boot from -kernel, needs a multiboot compatible image
+QB_DEFAULT_FSTYPE:qemux86-64 ?= "iso"
+
# RISC-V tunes set the BIOS, unset, and instruct QEMU to
# ignore the BIOS and boot from -kernel
QB_DEFAULT_BIOS:qemuriscv64 = ""
- The qemux86 port for helloworld-baremetal builds in the standard way, however, it uses NASM syntax for the startup code, hence we include a dependency to nasm-native, QEMU forces us to use an ELF file rather than a bin file to boot from this architecture using the -kernel parameter. - QEMU refuses to boot using the -kernel parameter for files containing an ELF64 header [1], instead, it requires a multiboot2 compatible image. We could create an image that contains a multiboot2 header by piggybacking into grub2-native, specifically grub-mkrescue, but it requires some extra runtime dependencies (xorriso which is currently part of meta-oe), and assumes a grub installation exists on the host. Due to host contamination and dependency complications, we dont rely on grub2, but rather do this process manually instead, the x86-64 port contains a stage1 bootloader, stage2 bootloader and a 64 bit baremetal app (multiboot2 compatible), booting into real (16 bit), protected (32 bit) and long (64 bit) modes, eventually running the helloworld-baremetal app. This is the reason why we need the code changes to use a separate Makefile, and create an image specifically for qemux86-64. $ runqemu nographic Booting from ROM.. Hello OpenEmbedded on x86! $ runqemu nographic Starting Stage 1 Bootloader Loading Stage 2 Bootloader Stage 2 Loaded. Jumping to Stage2 Bootloader In Stage 2 Done Hello OpenEmbedded on x86-64! [1] https://gitlab.com/qemu-project/qemu/-/blob/v7.2.0/hw/i386/multiboot.c#L199 Signed-off-by: Alejandro Enedino Hernandez Samaniego <alejandro@enedino.org> --- .../baremetal-helloworld_git.bb | 22 +++++++++++++++++-- meta/classes-recipe/baremetal-image.bbclass | 5 +++++ 2 files changed, 25 insertions(+), 2 deletions(-)