RE: how to prevent automatic dtb load?

[Chan Kim]

Hi, Alex Bennée

Yes, you are right. I tried again with that -dtb option like this.

qemu-system-aarch64  -machine 
ab21q,gic-version=max,secure=on,virtualization=true -cpu max -kernel u-boot-spl 
-m 8M -nographic -device loader,file=Image,addr=0x80200000 -dtb ab21m.dtb 
-chardev stdio,mux=on,id=char0 -serial chardev:char0 -serial chardev:char0

And it proceeded with the linux booting. Thanks!
(I thought I tried this before and had the same error, but it works ok now. 
Maybe I have done something wrong then.)
So I gather qemu loads the file I provide with -dtb option at the first address 
of the memory(0x80000000 in my case) and doesn't load the dtb it generated 
instead. My virtual machine is a modified version of arm/virt).

Chan Kim

>-----Original Message-----
>From: Alex Bennée <alex.bennee@linaro.org>
>Sent: Thursday, August 4, 2022 7:04 PM
>To: Chan Kim <ckim@etri.re.kr>
>Cc: qemu-discuss@nongnu.org
>Subject: Re: how to prevent automatic dtb load?
>
>
>"Chan Kim" <ckim@etri.re.kr> writes:
>
>> Hello experts,
>>
>> While emulating u-boot program which loads linux, I found even if I
>> load my dtb file at 0x80000000 using -device loader,file=xxx,addr=yyy
>> the qemu program loads the dtb it generated at 0x80000000. And it gives
>me this error.
>
>What is your full command line? QEMU only generates DTBs for some dynamic
>models, otherwise you should be providing one via the -dtb option.
>
>>
>> The following two regions overlap (in the cpu-memory-0 address space):
>>
>>   arch/arm64/boot/dts/arm/ab21m.dtb (addresses 0x0000000080000000 -
>> 0x0000000080000994)
>>
>>   dtb (addresses 0x0000000080000000 - 0x0000000080100000)
>>
>> make: *** [Makefile.qemu:22: run_uboot] Error 1
>>
>> I tried setting skip_dtb_autoload to true in my machine to no avail.
>>
>> How can I avoid automatic dtb load?
>>
>> Thanks in advance.
>>
>> Chan Kim
>
>
>--
>Alex Bennée