ast2700a0-evb machine hangs in U-Boot when trying to determine the RAM size

Host environment

• Operating system: RHEL 10
• OS/kernel version: 6.12.0-80.el10.s390x
• Architecture: s390x
• QEMU flavor: qemu-system-aarch64
• QEMU version: QEMU emulator version 10.0.50 (v10.0.0-877-g8648138789-dirty)
• QEMU command line:

  $ qemu-system-aarch64 -machine ast2700a0-evb  -m 1g ... 

Emulated/Virtualized environment

• Operating system: OpenBMC Aspeed SDK
• OS/kernel version: v09.06
• Architecture: aarch64

Description of problem

On a BE host, the ast2700a0-evb machine hangs in U-Boot when trying to determine the RAM size if the RAM size is set to a value other than 8 GB.

Steps to reproduce

1. ./qemu-system-aarch64 -machine ast2700a0-evb -m 1g

Additional information

On a BE host, if I run an ast2700a0-evb machine :

$ qemu-system-aarch64 -machine ast2700a0-evb  ...
...
U-Boot 2023.10-v00.05.06 (Mar 26 2025 - 05:59:26 +0000)

SOC: AST2700-A0
Model: AST2700 EVB
DRAM:  8 GiB (effective 0 Bytes)

QEMU hangs.

If the RAM size is defined to 8g

$ qemu-system-aarch64 -machine ast2700a0-evb -m 8g  ...
...
U-Boot 2023.10-v00.05.06 (Mar 26 2025 - 05:59:26 +0000)

SOC: AST2700-A0
Model: AST2700 EVB
DRAM:  8 GiB
aspeed_dp dp@12c0a000: aspeed_dp_probe(): Failed to access dp. version(0)
Core:  125 devices, 27 uclasses, devicetree: separate

machine boots.

Whereas, with an ast2700a1-evb machine :

$ qemu-system-aarch64 -machine ast2700a1-evb  ...
...
U-Boot 2023.10-v00.05.06 (Mar 26 2025 - 05:59:26 +0000)

SOC: AST2700-A1
Model: AST2700 EVB
DRAM:  1 GiB
aspeed_dp dp@12c0a000: aspeed_dp_probe(): Failed to access dp. version(0)
Core:  125 devices, 27 uclasses, devicetree: separate

machine boots.

$ qemu-system-aarch64 -machine ast2700a1-evb -m 8g  ...
...
U-Boot 2023.10-v00.05.06 (Mar 26 2025 - 05:59:26 +0000)

SOC: AST2700-A1
Model: AST2700 EVB
DRAM:  8 GiB
aspeed_dp dp@12c0a000: aspeed_dp_probe(): Failed to access dp. version(0)
Core:  125 devices, 27 uclasses, devicetree: separate

machine boots.