Re: [meta-arm] fvp-base doesn't support armv8.2

I forked off the scarthgap branch some time ago (SHA1 commit and date
below), parked and recently resumed my work on it.

$ git branch -r --contains a8fe9d22eaefc294f91096c6a32663e2f4ab3b10
  origin/scarthgap
$ git log --format=format:%cd -1 a8fe9d22eaefc294f91096c6a32663e2f4ab3b10
Mon Jan 6 06:00:11 2025 -0500

My goal is to have a Cortex-A55 simulated which is armv8.2.

I followed Ross's suggestion

meta-arm-bsp/recipes-bsp/u-boot/u-boot-fvp-base.inc

-EXTRA_OEMAKE += "ARM_ARCH_MAJOR=8 ARM_ARCH_MINOR=4"
+EXTRA_OEMAKE += "ARM_ARCH_MAJOR=8 ARM_ARCH_MINOR=2"

and it worked. Seeing the model booted up to Linux prompt.

Connected with arm ds and the midr_el1 shows me this MIDR_EL1 0x410FD0F0 32 RO.
Implementer Arm Limited. 8 RO
Variant 0x0 4 RO
Architecture Architectural features are individually identified in the
ID_* registers. 4 RO
PartNum 0xD0F 12 RO
Revision 0x0 4 RO

I guess for the ARM AEM models there is really no way to read it back
if the model implements version 8.2, isn' it?





On Tue, 10 Jun 2025 at 12:42, Marek <[email protected]> wrote:
>
> Thanks Jon and Ross!
>
> On Mon, 9 Jun 2025 at 15:54, Ross Burton <[email protected]> wrote:
> >
> > On 8 Jun 2025, at 21:14, Marek Bykowski via lists.yoctoproject.org <[email protected]> wrote:
> > >
> > > When I simply change to "require conf/machine/include/arm/arch-armv8-2a.inc" and "FVP_CONFIG[cluster0.has_arm_v8-2] = "1"" and "FVP_CONFIG[cluster1.has_arm_v8-2] = "1" " the FVP_Base_RevC-2xAEMvA doesn't boot at all. I do not see even a single line of log even from bl1. Would that mean the SW stack/Yocto doesn't support armv8.2 for fvp-base model platform?
> >
> > If you’re using a recent meta-arm which sets the base-fvp to v8.4 cores, then you didn’t also tell TF-A to use 8.2 and it might have been trying to use 8.4 instructions.  See this in the TF-A recipe:
> >
> > EXTRA_OEMAKE += "ARM_ARCH_MAJOR=8 ARM_ARCH_MINOR=4”
> >
> > Ross
>
>
>
> --
> Slán,
> Marek



--
Slán,
Marek