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Diffstat (limited to 'classes/qemuboot-xen-dtb.bbclass')
| -rw-r--r-- | classes/qemuboot-xen-dtb.bbclass | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/classes/qemuboot-xen-dtb.bbclass b/classes/qemuboot-xen-dtb.bbclass new file mode 100644 index 00000000..d43d23a3 --- /dev/null +++ b/classes/qemuboot-xen-dtb.bbclass @@ -0,0 +1,210 @@ +# Enable booting Xen with qemuboot / runqemu: generate device tree +# +# Copyright (c) 2021 Star Lab Corp. All rights reserved. +# +# Author: Christopher Clark <christopher.clark@starlab.io> + +# Interface variables: +# +# QB_DTB : defined in qemuboot.bbclass. +# If set, this class will generate the specified device tree file. +# +# QB_XEN_CMDLINE_EXTRA : +# A string to be appended to the default Xen hypervisor boot command line, +# for supplying Xen boot options. +# The device tree that this bbclass generates will contain Xen command +# line options to connect the Xen console to the Qemu serial port. +# +# QB_XEN_DOMAIN_MODULES : +# A space-separated list of colon-separated entries: +# "<file for the module>:<load memory address>:<module compatibility string>" +# +# QB_XEN_DOM0_BOOTARGS : +# A string for specifying Dom0 boot options for the Xen section of the device +# tree. +# +# QB_XEN_DTB_TASK_DEPENDS : +# The task dependencies for the DTB generation. A default is provided. +# +# See also: Other QB_ variables as defined by the qemuboot.bbclass. + +write_lops_xen_section() { + DOM0_BOOTARGS="$2" + cat <<EOF >"$1" +/dts-v1/; +/ { + compatible = "system-device-tree-v1"; + lops { + /* Connect the Xen console to Qemu dtuart */ + lop_1 { + compatible = "system-device-tree-v1,lop,code-v1"; + code = " + chosen = node.tree['/chosen'] + stdout_path = str(chosen['stdout-path'].value[0]) + chosen['xen,xen-bootargs'] = \ + 'console=dtuart dtuart=%s' % stdout_path + return True + "; + }; + lop_2 { + compatible = "system-device-tree-v1,lop,modify"; + modify = "/chosen:xen,dom0-bootargs:${DOM0_BOOTARGS}"; + }; + lop_3 { + compatible = "system-device-tree-v1,lop,modify"; + modify = "/chosen:#address-cells:<1>"; + }; + lop_4 { + compatible = "system-device-tree-v1,lop,modify"; + modify = "/chosen:#size-cells:<1>"; + }; + }; +}; +EOF +} + +write_lop_add_to_xen_cmdline() { + EXTRA_XEN_BOOTARGS="$2" + cat <<EOF >"$1" +/dts-v1/; +/ { + compatible = "system-device-tree-v1"; + lops { + lop_1 { + compatible = "system-device-tree-v1,lop,code-v1"; + options = "extra_xen_bootargs:${EXTRA_XEN_BOOTARGS}"; + code = " + chosen = node.tree['/chosen'] + xen_bootargs = str(chosen['xen,xen-bootargs'].value) + chosen['xen,xen-bootargs'] = '%s %s' % \ + (xen_bootargs, extra_xen_bootargs) + return True + "; + }; + }; +}; +EOF +} + +write_lop_add_chosen_module() { + ADDR="$2" + SIZE="$3" + MODULE_TYPE="$4" + cat <<EOF >"$1" +/dts-v1/; +/ { + compatible = "system-device-tree-v1"; + lops { + lop_1 { + compatible = "system-device-tree-v1,lop,add"; + node_src = "module@${ADDR}"; + node_dest = "/chosen/module@${ADDR}"; + + module@${ADDR} { + compatible = "multiboot,module", "${MODULE_TYPE}"; + reg = <${ADDR} ${SIZE}>; + }; + }; + }; +}; +EOF +} + +generate_xen_qemuboot_dtb() { + # First: invoke qemu to generate an initial device tree. + # Parameters supplied here inspired by inspection of: + # runqemu "${IMAGE_BASENAME}" nographic slirp \ + # qemuparams='-dtb "" -machine dumpdtb=${B}/qemu-dumped.dtb' + ${QB_SYSTEM_NAME} \ + -device qemu-xhci \ + -device usb-tablet \ + -device usb-kbd \ + ${QB_MACHINE} \ + ${QB_CPU} \ + ${QB_SMP} \ + ${QB_MEM} \ + -nographic \ + -serial mon:stdio \ + -machine "dumpdtb=${B}/qemu-dumped.dtb" + + # Lopper generates temporary files in cwd, so run it within ${B} + cd "${B}" + write_lops_xen_section "${B}/lop-insert-xen-section.dts" \ + "${QB_XEN_DOM0_BOOTARGS}" + + write_lop_add_to_xen_cmdline "${B}/lop-xen-cmdline.dts" \ + "${QB_XEN_CMDLINE_EXTRA}" + + if [ -z "${QB_XEN_DOMAIN_MODULES}" ]; then + bbwarn "No domain modules: please set QB_XEN_DOMAIN_MODULES" + fi + + for DOMAIN_MODULE in ${QB_XEN_DOMAIN_MODULES} + do + MODULE_FILE="$(echo ${DOMAIN_MODULE} | cut -f1 -d:)" + ADDR="$(echo ${DOMAIN_MODULE} | cut -f2 -d:)" + MODULE_TYPE="$(echo ${DOMAIN_MODULE} | cut -f3 -d:)" + RESOLVED_FILE="$(readlink -f ${MODULE_FILE})" + SIZE=$(printf '0x%x\n' $(stat -c '%s' "${RESOLVED_FILE}")) + [ "x${SIZE}" != "x0x0" ] || bbfatal No module: "${MODULE_FILE}" + write_lop_add_chosen_module "${B}/lop-add-module-${ADDR}.dts" \ + "${ADDR}" "${SIZE}" "${MODULE_TYPE}" + LOP_MODULE_ARGS="${LOP_MODULE_ARGS} -i ${B}/lop-add-module-${ADDR}.dts" + done + + QEMUBOOT_DTB="${IMGDEPLOYDIR}/${QB_DTB}" + QEMUBOOT_DTB_LINK="${IMGDEPLOYDIR}/${QB_DTB_LINK}" + + lopper --werror --verbose \ + -i "${B}/lop-insert-xen-section.dts" \ + -i "${B}/lop-xen-cmdline.dts" \ + ${LOP_MODULE_ARGS} \ + -f -o "${QEMUBOOT_DTB}" \ + "${B}/qemu-dumped.dtb" + + # To assist debugging: + dtc -I dtb -O dts -o "${B}/output.dts" "${QEMUBOOT_DTB}" + + if [ "${QEMUBOOT_DTB_LINK}" != "${QEMUBOOT_DTB}" ] ; then + if [ -e "${QEMUBOOT_DTB_LINK}" ] ; then + rm "${QEMUBOOT_DTB_LINK}" + fi + ln -s "${QB_DTB}" "${QEMUBOOT_DTB_LINK}" + fi +} + +do_write_xen_qemuboot_dtb() { + # Not all architectures qemuboot with a device tree binary, so check + # to see if one is needed. This allows this bbclass file to be used + # in the same image recipe for multiple architectures. + if [ -n "${QB_DTB}" ] && [ -n "${QB_SYSTEM_NAME}" ] ; then + generate_xen_qemuboot_dtb + fi +} + +addtask do_write_xen_qemuboot_dtb after do_write_qemuboot_conf before do_image +# Task dependency: +# An expected common case is that the kernel for at least one of the initial +# domains (eg. dom0) is deployed from the virtual/kernel recipe, so +# add virtual/kernel:do_deploy as a task dependency here since the kernel size +# needs to be known for generating the device tree. +# Dependencies are only introduced if a device tree will be generated. +QB_XEN_DTB_TASK_DEPENDS ?= " \ + ${@[ ' \ + qemu-helper-native:do_populate_sysroot \ + lopper-native:do_populate_sysroot \ + dtc-native:do_populate_sysroot \ + virtual/kernel:do_deploy \ + ', ''][d.getVar('QB_DTB') == '' or d.getVar('QB_DTB') is None]} \ + " +do_write_xen_qemuboot_dtb[depends] = "${QB_XEN_DTB_TASK_DEPENDS}" + +def qemuboot_dtb_vars(d): + build_vars = ['MACHINE', 'TUNE_ARCH', 'DEPLOY_DIR_IMAGE', + 'KERNEL_IMAGETYPE', 'IMAGE_NAME', 'IMAGE_LINK_NAME', + 'STAGING_DIR_NATIVE', 'STAGING_BINDIR_NATIVE', + 'STAGING_DIR_HOST', 'SERIAL_CONSOLES'] + return build_vars + [k for k in d.keys() if k.startswith('QB_')] + +do_write_qemuboot_dtb[vardeps] += "${@' '.join(qemuboot_dtb_vars(d))}" +do_write_qemuboot_dtb[vardepsexclude] += "TOPDIR" |