Re: [Qemu-devel] [RFC v1 4/6] target_arm: Update armv7_init to support more parameters

[Martin Galvan]

On Tue, Sep 9, 2014 at 8:43 PM, Alistair Francis <address@hidden> wrote:
> On Wed, Sep 10, 2014 at 12:03 AM, Martin Galvan
> <address@hidden> wrote:
>>>> @@ -259,7 +272,13 @@ qemu_irq *armv7m_init(MemoryRegion *system_memory,
>>>>      vmstate_register_ram_global(hack);
>>>>      memory_region_add_subregion(system_memory, 0xfffff000, hack);
>>>>
>>>> -    qemu_register_reset(armv7m_reset, cpu);
>>>> +    reset_args = (ARMV7MResetArgs) {
>>>> +        .cpu = cpu,
>>>> +        .reset_pc = entry,
>>>> +        .reset_sp = (0x20000000 + ((192 * 1024) * 2)/3),
>>>
>>> Why is the manual sp setting needed? I thought the V7M specific CPU
>>> reset code handled this? Does Martins ARMv7M ROM reset patch help by
>>> any chance?
>>>
>>> Regards,
>>> Peter
>>
>> Indeed, I don't think that would be necessary with my patch. What are
>> those hardcoded magic numbers?
>
> The hard coded numbers are there basically there because they worked at
> one point and I haven't removed them yet. There is also no memory aliasing,
> so this gets around out of memory access errors from QEMU.
>
> I haven't had to chance to try your patch yet Martin, but hopefully it removes
> the need for any of the reset changes I made.

My patch deals with the initial MSP, PC and Thumb values not being set
correctly on reset. I don't know if it's in the main tree yet, but you
can see it here:

https://patchwork.ozlabs.org/patch/386497/

-- 

Martín Galván

Software Engineer

Taller Technologies Argentina


San Lorenzo 47, 3rd Floor, Office 5

Córdoba, Argentina

Phone: 54 351 4217888 / +54 351 4218211