Re: [PATCH v2 1/3] ARM: tegra: basic support for Trusted Foundations

[Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>]

On 06/14/2013 02:27 AM, Alexandre Courbot wrote:
> On Fri, Jun 14, 2013 at 4:19 AM, Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> wrote:
>> On 06/13/2013 03:12 AM, Alexandre Courbot wrote:
>>> Add basic support for booting secondary processors on Tegra devices
>>> using the Trusted Foundations secure monitor.

>>> diff --git a/arch/arm/mach-tegra/firmware.c b/arch/arm/mach-tegra/firmware.c
>>
>>> +void __init tegra_init_firmware(void)
...
>>> +     node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations");
>>> +     if (node && !IS_ENABLED(CONFIG_TEGRA_TRUSTED_FOUNDATIONS))
>>> +             pr_warn("Trusted Foundations detected but support missing!\n");
>>> +#if IS_ENABLED(CONFIG_TEGRA_TRUSTED_FOUNDATIONS)
>>> +     else if (node)
>>> +             register_firmware_ops(&tegra_trusted_foundations_ops);
>>> +#endif
>>> +}
>>
>> Is it worth continuing on in the node && !IS_ENABLED case here? After
>> all, we can be pretty certain that the write to the CPU reset vector is
>> immediately going to trap...
> 
> That's what was happening until 3.9, but from 3.10 on the trap is
> apparently handled and the boot completes (although with only one
> processor).

Why does that happen; surely the kernel shouldn't be ignoring failures?
How does it recover?