This is not an officially supported Google product.
This is a super simple Boot ROM that is intended to be used as a -bios image
for QEMU when emulating an NPCM7xx-based machine.
If you have a 32-bit ARM compiler installed as arm-none-eabi-gcc, simply run
make.
If your ARM compiler has a different name, you'll need to override the
CROSS_COMPILE prefix, e.g. like this:
make CROSS_COMPILE=arm-linux-gnueabi-
If either case is successful, a npcm7xx_bootrom.bin file will be produced.
The Boot ROM image may be passed to a QEMU system emulator using the -bios option. For example like this:
qemu-system-arm -machine quanta-gsj -nographic \
-bios "${IMAGES}/npcm7xx_bootrom.bin"
-drive file="${IMAGES}/image-bmc,if=mtd,bus=0,unit=0,format=raw,snapshot=on"
- Secure boot is not supported.
- Only booting from offset 0 of the flash at SPI0 CS0 is implemented.
- Fallback images (if the first image doesn't boot) are not implemented.
- Exception vectors are copied to SRAM, but not remapped.
- Most OTP bits and straps are not honored.
- The reset type bits are not updated.
- OTP protection is not implemented.
- No clock initialization is performed.
- UART programming protocol is not implemented.
- Host notification through the PCI mailbox is not implemented.
- Most fields in the ROM status structure are not set.