[Qemu-devel] [Bug 1723984] Re: ID_MMFR0 has an invalid value on aarch64 cpu (A57, A53)

[Bug]

I see your point. Thank you for the advice. I'm doing some low-level
check to be sure to be on a known platform, so this midr based code is
very localized. For the "core" of the kernel, I'm mostly using (1) as
access to MMU registers are localized in armv7/armv8 specialized sub-
directories.

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1723984

Title:
  ID_MMFR0 has an invalid value on aarch64 cpu (A57, A53)

Status in QEMU:
  New

Bug description:
  The ID_MMFR0 register, accessed from aarch64 state as an invalid value:
  - ARM ARM v8 documentation (D7.2 General system control registers) described 
bits AuxReg[23:20] to be
    "In ARMv8-A the only permitted value is 0010"
  - Cortex A53 and Cortex A57 TRM describe the value to be 0x10201105, so 
AuxReg[23:20] is 0010 too
  - in QEMU target/arm/cpu64.c, the relevant value is
    cpu->id_mmfr0 = 0x10101105;

  The 1 should be changed to 2.

  Spotted & Tested on the following qemu revision:

  commit 48ae1f60d8c9a770e6da64407984d84e25253c69
  Merge: 78b62d3 b867eaa
  Author: Peter Maydell <address@hidden>
  Date:   Mon Oct 16 14:28:13 2017 +0100

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1723984/+subscriptions