diff options
Diffstat (limited to 'README')
| -rw-r--r-- | README | 22 |
1 files changed, 3 insertions, 19 deletions
@@ -1,6 +1,6 @@ A simple x86 firmware that can boot Linux. -Most of QEMU's 500-700 ms startup time is spent: +Most of QEMU's startup time is spent: * in the dynamic linker. This can be reduced by 150 ms simply by compiling a stripped down QEMU: @@ -17,10 +17,8 @@ Most of QEMU's 500-700 ms startup time is spent: * in the BIOS. qboot saves another 150 ms. -* in fw_cfg. qboot can use the new DMA interface to fw_cfg from QEMU 2.7+. - Alternatively, kernel and initrd can be put in a CoreBoot cbfs image - stored in flash. However, flash has a limit of 8 MB. In either case - 350 ms are saved, bringing the startup time down to 60 ms. +* until QEMU 2.7+, in fw_cfg. qboot uses the DMA interface which is pretty + much instantaneous. Compile qboot ============= @@ -39,26 +37,12 @@ The result will be a 64K file named bios.bin. Usage ===== -fw_cfg based example: - $ qemu-kvm -bios bios.bin \ -kernel /boot/vmlinuz-4.0.3-300.fc22.x86_64 \ -serial mon:stdio -append 'console=ttyS0,115200,8n1' -cbfs-based example (pflash isn't the definitive interface though): - - $ dd if=/dev/zero of=boot.bin bs=4096 count=1 - $ cbfstool cbfs.rom create -s 8128k -B boot.bin -m x86 -o 0x1000 - $ cbfstool cbfs.rom add -f /boot/vmlinuz-4.0.3-300.fc22.x86_64 -n vmlinuz -t raw - $ echo 'console=ttyS0,115200,8n1' > cmdline - $ cbfstool cbfs.rom add -f cmdline -n cmdline -t raw - $ qemu-kvm -drive if=pflash,file=bios.bin,readonly=on \ - -drive if=pflash,file=cbfs.rom,readonly=on \ - -serial mon:stdio - TODO ==== * SMBIOS tables * Add the possibility to configure out PIC and PCI bridge initialization -* Possibly drop cbfs support, superseded by fw_cfg DMA |