[U-Boot] [ppc] qemu-ppce500 howto

[Alexander Graf]

On 25.05.2014, at 13:10, Alon Bar-Lev <alon.barlev at gmail.com> wrote:

> On Sun, May 25, 2014 at 1:08 PM, Alexander Graf <agraf at suse.de> wrote:
>> 
>> 
>> On 24.05.14 09:23, Alon Bar-Lev wrote:
>>> 
>>> On Thu, May 22, 2014 at 12:04 PM, Alexander Graf <agraf at suse.de> wrote:
>>>> 
>>>> 
>>>> On 22.05.14 09:52, Alon Bar-Lev wrote:
>>>>> 
>>>>> Hi,
>>>>> 
>>>>> Trying to run the qemu-ppce500 within qemu. I am using -bios u-boot.bin and no luck, I get live signal.
>>>>> 
>>>>> I am using latest u-boot master and qemu master.
>>>>> 
>>>>> Command:
>>>>> $ ./qemu-system-ppc -M ppce500 -nographic -bios u-boot.bin
>>>>> 
>>>>> Tried to load u-boot as well, same.
>>>> 
>>>> 
>>>> Yes, that command should work with the right patches :). Unfortunately they are not in master yet, but instead waiting in my queue:
>>>> 
>>>>   https://github.com/agraf/qemu
>>>> 
>>>> Please give things a try with the ppc-next branch in there. That should get things working for you.
>>>> 
>>> WORKING! thanks!
>>> 
>>> Is there any support for flush and/or mtd for this target (-drive
>>> if=pflash, -mtdblock)?
>> 
>> 
>> I haven't implemented pflash yet, sorry. Do you need the flash device for configuration storage or as backing storage for your kernel?
>> 
> 
> Well, I wish both... :)
> 
> boot qemu as if it were a target....
> 
> 1. put u-boot on pflash, and boot from it.
> 2. have backing storage for kernel (can be mtd).
> 3. have data partition (can be mtd).
> 
> we can skip (1) as -bios is good enough... but for (2), (3) I do not

For (2) you can use the -kernel option. It should make the payload's physical address available through an environment variable. If it's a uImage, it will get loaded automatically.
For (3) you can use all the emulated block storage options QEMU provides, such as virtio-pci or ahci.

> see solution but have either mtd or other block device support... is
> that possible?

It's definitely possible, yes :). I simply didn't implement any mtd device emulation so far in the QEMU machine model. But patches are definitely welcome!


Alex