How should I build u-boot for qemu_arm64_defconfig and run it on arm64 qemu virt machine?

[Chan Kim]

Hello experts,

 

Today I tried this test from scratch.

In my environment, CROSS_COMPILE=aarch64-none-elf.

Under u-boot directory, when I do 'make CROSS_COMPILE=aarch64-none-elf- qemu_arm64_defconfig' and 'make -j28', I see this error at the end.

 

aarch64-none-elf-ld.bfd: invalid length for memory region .sram

 

after examining it, I added in include/configs/qemu-arm.h,

 

#define CONFIG_SPL_MAX_SIZE value to 0x400000

 

After fixing it, I got another similar error for .sdram and I added in include/configs/qemu-arm.h,

 

#define CONFIG_SPL_BSS_START_ADDR 0x40800000

#define CONFIG_SPL_BSS_MAX_SIZE 0x100000

 

Now I can do 'make -j28' with no error.

But I found I have both ‘u-boot’ and ‘spl/u-boot-spl’ generated and I realized for this qemu_arm64_defconfig, CONFIG_SPL=y and I get both u-boot proper and u-boot spl. (SPL: secondary program loader, proper: main bootloader. SPL runs first and the proper runs next).

 

Until now I did objcopy of the u-boot(proper) and then extended it to 0x400000 byte. (the pflash size of the virt machine which starts at address 0x00000000).

$ aarch64-none-elf-objcopy -O binary u-boot.v2022.07/u-boot pflashp.img

$ dd if=/dev/zero of=pflashp.img bs=1c count=1 seek=67108863

 

And the qemu command is :

$ qemu-6.2.0/build/aarch64-softmmu/qemu-system-aarch64 -machine virt,gic-version=max,secure=on,virtualization=true -cpu max -drive if=pflash,file=pflashp.img -m 2G -nographic -device loader,file=linux-5.15.68/arch/arm64/boot/Image,addr=0x80200000

 

The qemu virt machine has RAM from 0x40000000 until 0xbfffffff.

And I could see u-boot runs and it waits input for 3 seconds and outputs the u-boot prompt.

This is running u-boot (proper) from address 0 but since I have u-boot-spl too, I should run it from u-boot-spl first, shouldn’t I?

 

How am I supposed to run u-boot-spl and u-boot on this qemu machine? (from lds files, it looks like they both start at address 0).

(qemu machine is arm64 virt machine, qemu 6.2.0).

 

 

Thank you.

 

Chan Kim