arm64: cpufeature: Add support for the MPAM v0.1 architecture version

According to the MPAM spec [1], the supported architecture versions are
v1.0, v1.1 and v0.1. MPAM versions v0.1 and v1.1 are functionally
identical, but v0.1 additionally supports the FORCE_NS feature.

ID_AA64PR | ID_AA64PR | MPAM Extension | Notes
F0_EL1.   | F1_EL1.   | Architecture   |
MPAM      | MPAM_frac | version        |
---------------------------------------------------------------------------
0b0000    | 0b0001    | v0.1           | MPAM v0.1 is implemented.
          |           |                | MPAM v0.1 is the same as MPAM v1.1
          |           |                | with FORCE_NS which is
          |           |                | incompatible with MPAM v1.0.
---------------------------------------------------------------------------
0b0001    | 0b0000    | v1.0           | MPAM v1.0 is implemented.
---------------------------------------------------------------------------
0b0001    | 0b0001    | v1.1           | MPAM v1.1 is implemented.
          |           |                | MPAM v1.1 includes all features of
          |           |                | MPAM v1.0.
          |           |                | It must not include FORCE_NS.

FORCE_NS is a feature that operates in EL3 mode. Consequently, the current
Linux MPAM driver is also compatible with MPAM v0.1. To support v0.1, the
existing driver which only checks ID_AA64PFR0_EL1.MPAM for the major
version needs to examine ID_AA64PFR1_EL1.MPAM_frac for the minor version
as well.

[1] https://developer.arm.com/documentation/ddi0598/db/?lang=en

Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

0 files changed, 0 insertions, 0 deletions