[U-Boot] [PATCH v2 3/8] sandbox: Add support for bootz

[Stephen Warren]

On 04/07/2015 02:40 PM, Simon Glass wrote:
> Hi Sjoerd,
>
> On 7 April 2015 at 01:56, Sjoerd Simons <sjoerd.simons at collabora.co.uk> wrote:
>> On Mon, 2015-04-06 at 15:40 -0600, Stephen Warren wrote:
>>> On 04/06/2015 03:02 PM, Sjoerd Simons wrote:
>>>> Add dummy bootz_setup implementation allowing the u-boot sandbox to
>>>> run bootz. This recognizes both ARM and x86 zImages to validate a
>>>> valid zImage was loaded.
>>>
>>>> diff --git a/arch/sandbox/lib/bootm.c b/arch/sandbox/lib/bootm.c
>>>
>>>> +int bootz_setup(ulong image, ulong *start, ulong *end)
>>>
>>>> +   *start = 0xdead;
>>>> +   *end = 0xbeef;
>>>> +   return 0;
>>>
>>> Isn't that going to cause the rest of bootz to access or jump to some
>>> bogus address and crash?
>>
>> A very good question. I hadn't actually double-checked what these values
>> are used for as things just worked and i got distracted by fixing other
>> bits & pieces.
>>
>> Looking through the code, these values are only used to add an LMB
>> region directly after the kernel entry load address. As the sandbox
>> architecture doesn't define either arch_lmb_reserve nor
>> board_lmb_reserve these bogus values don't cause any issues (as they
>> don't seem to make the generic lmb code blow-up thatis), but it's
>> definitely not pretty.
>
> In the future we may want to emulate this with sandbox. Do you think
> instead of this we should read out the correct values from the image
> file? It seems odd to use fake values.
>
> In fact I wonder if this should use a common function with ARM, or
> perhaps part of it should be common?

I wonder if sandbox could somehow exec the loaded image (presumably it'd 
only support native executables then, not ARM/x86 zImages), or keep a 
handle to the file the data was loaded from and fdexec() if such an API 
exists?