Hello,

Currently, the CPU features exposed to the AST2600 QEMU machines are :

  half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt
  vfpd32 lpae evtstrm

But, the features of the Cortex A7 CPU on the Aspeed AST2600 A3 SoC
are :

  half thumb fastmult vfp edsp vfpv3 vfpv3d16 tls vfpv4 idiva idivt
  lpae evtstrm

NEON support should be dropped and, in that case, QEMU should
advertise a VFPv4 unit with 16 double-precision registers, and not 32
registers.

This problem was raised by a buildroot rootfs compiled with vfpv4.
Boot went fine under QEMU but on real HW, user space binaries had
issues with output. Compiling buildroot with vfpv4d16 fixed it and
I didn't dig further. Nevertheless, it would be nice to catch such
issues with QEMU.

Thanks,

C. 

Cédric Le Goater (2):
  target/arm: Disable VFPv4-D32 when NEON is not available
  ast2600: Drop NEON from the CPU features

 hw/arm/aspeed_ast2600.c | 2 ++
 target/arm/cpu.c        | 4 ++++
 2 files changed, 6 insertions(+)

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2.37.3