tree 3920525caad56ed5538244071a1caa4bd292a271
parent 14fdf070c53c06b7ffd58e5e05bea03a1f2b5564
author Stephan Gerhold <stephan@gerhold.net> 1638385342 +0100
committer Stephan Gerhold <stephan@gerhold.net> 1643897962 +0100

feat(gic): allow overriding GICD_PIDR2_GICV2 address

Older Qualcomm SoCs seem to have a custom Qualcomm implementation of
the GICv2 specification. It's mostly compliant but unfortunately it
looks like a mistake was made with the GICD_PIDR registers. PIDR2 is
defined to be at offset 0xFE8, but the Qualcomm implementation has it
at 0xFD8.

It looks like the entire PIDR0-3/4-7 block is swapped compared to the
ARM implementation: PIDR0 starts at 0xFD0 (instead of 0xFE0)
and PIDR4 starts at 0xFE0 (instead of 0xFD0).

Actually this only breaks a single assert in gicv2_main.c that checks
the GIC version: assert((gic_version == ARCH_REV_GICV2) ...
In release mode everything seems to work correctly.

To keep the code generic, allow affected platforms to override the
GICD_PIDR2_GICV2 register address in platform_def.h. Since this header
is typically included very early (e.g. from assert.h), add an #ifndef
so the definitions from platform_def.h takes priority.

Change-Id: I2929a8c1726f8d751bc28796567eb30b81eca2fe
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>