From mboxrd@z Thu Jan 1 00:00:00 1970 From: Romain Naour Date: Sun, 9 Feb 2020 19:03:22 +0100 Subject: [Buildroot] [PATCH v4 4/9] configs/qemu{x86, x86_64}: add a serial console In-Reply-To: <20200209180327.455426-1-romain.naour@smile.fr> References: <20200209180327.455426-1-romain.naour@smile.fr> Message-ID: <20200209180327.455426-5-romain.naour@smile.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net The current Buildroot defconfigs for qemu_x86 and qemu_x86_64 instantiate a console on tty1, which appears on QEMU's graphical window. Add a console on the serial port (ttyS0) to be used later for gitlab testing. This change is need since the script used for gitlab testing needs to use a serial output with pexpect. This change is similar to the one made for raspberrypi [1] to handle HDMI and serial console: This requires three changes: 1. have two 'console=' entries in the kernel command line: tty1, then ttyS0; 2. change BR2_TARGET_GENERIC_GETTY_PORT to "console", so it starts a getty on the last console= passed to the kernel, ttyS0; 3. add a new getty on tty1 to the generated inittab. Step 2 is actually obtained by removing BR2_TARGET_GENERIC_GETTY_PORT entirely from the defconfigs, since "console" is the default value. Step 3 requires a post-build script since the Buildroot makefiles can configure only one console. Note: instead of simply adding a new getty on ttyS0 (which would work) this patch actually changes BR2_TARGET_GENERIC_GETTY_PORT to instantiate a console on UART, then adds back tty1 via post-build.sh. This is done only to avoid the "GENERIC_SERIAL" comment where we instantiate a console on QEMU graphical window, then instantiate a really-serial console on another line. The result is these two inittab lines: console::respawn:/sbin/getty -L console 0 vt100 # GENERIC_SERIAL tty1::respawn:/sbin/getty -L tty1 0 vt100 # QEMU graphical window [1] 20878a1017e2bf7eb8c5f870dc6d2641493cb0f9 Signed-off-by: Romain Naour --- board/qemu/x86/post-build.sh | 11 +++++++++++ board/qemu/x86/readme.txt | 2 +- board/qemu/x86_64/post-build.sh | 11 +++++++++++ board/qemu/x86_64/readme.txt | 2 +- configs/qemu_x86_64_defconfig | 4 +++- configs/qemu_x86_defconfig | 4 +++- 6 files changed, 30 insertions(+), 4 deletions(-) create mode 100755 board/qemu/x86/post-build.sh create mode 100755 board/qemu/x86_64/post-build.sh diff --git a/board/qemu/x86/post-build.sh b/board/qemu/x86/post-build.sh new file mode 100755 index 0000000000..bf83a002c2 --- /dev/null +++ b/board/qemu/x86/post-build.sh @@ -0,0 +1,11 @@ +#!/bin/sh + +set -u +set -e + +# Add a console on tty1 +if [ -e ${TARGET_DIR}/etc/inittab ]; then + grep -qE '^tty1::' ${TARGET_DIR}/etc/inittab || \ + sed -i '/GENERIC_SERIAL/a\ +tty1::respawn:/sbin/getty -L tty1 0 vt100 # QEMU graphical window' ${TARGET_DIR}/etc/inittab +fi diff --git a/board/qemu/x86/readme.txt b/board/qemu/x86/readme.txt index 42fc2439da..3bbafecf91 100644 --- a/board/qemu/x86/readme.txt +++ b/board/qemu/x86/readme.txt @@ -1,6 +1,6 @@ Run the emulation with: - qemu-system-i386 -M pc -kernel output/images/bzImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append "rootwait root=/dev/vda" -net nic,model=virtio -net user + qemu-system-i386 -M pc -kernel output/images/bzImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append "rootwait root=/dev/vda console=tty1 console=ttyS0" -serial stdio -net nic,model=virtio -net user Optionally add -smp N to emulate a SMP system with N CPUs. diff --git a/board/qemu/x86_64/post-build.sh b/board/qemu/x86_64/post-build.sh new file mode 100755 index 0000000000..bf83a002c2 --- /dev/null +++ b/board/qemu/x86_64/post-build.sh @@ -0,0 +1,11 @@ +#!/bin/sh + +set -u +set -e + +# Add a console on tty1 +if [ -e ${TARGET_DIR}/etc/inittab ]; then + grep -qE '^tty1::' ${TARGET_DIR}/etc/inittab || \ + sed -i '/GENERIC_SERIAL/a\ +tty1::respawn:/sbin/getty -L tty1 0 vt100 # QEMU graphical window' ${TARGET_DIR}/etc/inittab +fi diff --git a/board/qemu/x86_64/readme.txt b/board/qemu/x86_64/readme.txt index 4a1c0c0ff5..93ac22a947 100644 --- a/board/qemu/x86_64/readme.txt +++ b/board/qemu/x86_64/readme.txt @@ -1,6 +1,6 @@ Run the emulation with: - qemu-system-x86_64 -M pc -kernel output/images/bzImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append "rootwait root=/dev/vda" -net nic,model=virtio -net user + qemu-system-x86_64 -M pc -kernel output/images/bzImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append "rootwait root=/dev/vda console=tty1 console=ttyS0" -serial stdio -net nic,model=virtio -net user Optionally add -smp N to emulate a SMP system with N CPUs. diff --git a/configs/qemu_x86_64_defconfig b/configs/qemu_x86_64_defconfig index cbd0413a90..b561e42e51 100644 --- a/configs/qemu_x86_64_defconfig +++ b/configs/qemu_x86_64_defconfig @@ -3,12 +3,14 @@ BR2_x86_64=y # System BR2_SYSTEM_DHCP="eth0" -BR2_TARGET_GENERIC_GETTY_PORT="tty1" # Filesystem BR2_TARGET_ROOTFS_EXT2=y # BR2_TARGET_ROOTFS_TAR is not set +# Image +BR2_ROOTFS_POST_BUILD_SCRIPT="board/qemu/x86_64/post-build.sh" + # Linux headers same as kernel, a 4.19 series BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_19=y diff --git a/configs/qemu_x86_defconfig b/configs/qemu_x86_defconfig index 6ca3ab9627..52f1744344 100644 --- a/configs/qemu_x86_defconfig +++ b/configs/qemu_x86_defconfig @@ -4,12 +4,14 @@ BR2_x86_pentiumpro=y # System BR2_SYSTEM_DHCP="eth0" -BR2_TARGET_GENERIC_GETTY_PORT="tty1" # Filesystem BR2_TARGET_ROOTFS_EXT2=y # BR2_TARGET_ROOTFS_TAR is not set +# Image +BR2_ROOTFS_POST_BUILD_SCRIPT="board/qemu/x86/post-build.sh" + # Linux headers same as kernel, a 4.19 series BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_19=y -- 2.24.1