Deprecate nwfpe emulation?

[Richard Henderson <richard.henderson@linaro.org>]

On 1/27/25 09:46, Peter Maydell wrote:
> On Mon, 27 Jan 2025 at 17:27, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>> On 27/1/25 12:27, Peter Maydell wrote:
>>> We have one test case in check-tcg which purports to be checking
>>> iwMMXt. In fact it is doing no such thing: it runs the test without
>>> selecting an iwMMXt CPU, which means the iwMMXt insns are interpreted
>>> as FPA11 insns by the linux-user emulate_arm_fpa11() code. So the test
>>> prints garbage and then succeeds anyway.
>>
>> Uh...
> 
> It had me confused for a while, because I'd convinced myself
> by code inspection that we only enabled iwMMXt if you
> manually asked for a pxa2xx CPU and not in the default 'max'
> CPU, and then I found this test case that we were running
> with the default CPU type and which was apparently passing :-)

Any chance we can deprecate the fpa11 stuff too?

I see it's still enabled by the kernel for some boards,
but it depends on really old configury:

config FPE_NWFPE
         bool "NWFPE math emulation"
         depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
         help
           Say Y to include the NWFPE floating point emulator in the kernel.
           This is necessary to run most binaries. Linux does not currently
           support floating point hardware so you need to say Y here even if
           your machine has an FPA or floating point co-processor podule.

No thumb2, no eabi, and oabi_compat enabled.
I suspect that's a very rare configuration these days.

I'll note the help message is somewhat dated.  :-)


r~