feat(k3low): optimize firewall configuration to minimize boot time

Currently, ROM configured firewalls are removed during SOC init for
AM62L by iterating over all regions of the firewalls and then t

feat(k3low): optimize firewall configuration to minimize boot time

Currently, ROM configured firewalls are removed during SOC init for
AM62L by iterating over all regions of the firewalls and then taking
action if they are active. In this process, we end up making an
unnecessarily large number of TISCI calls, which negatively impacts the
boot time.

Instead, pre-determine the list of firewall IDs and respective regions
configured by ROM, and add a static table to only re-configure those
regions. This greatly reduces the number of TISCI calls we are making,
and hence minimizes boot time impact.

While re-configuring, set a permissive background firewall enabling
access to everyone. This is equivalent to keeping them disabled.
However, when going into low-power modes, TIFS doesn't save context for
disabled firewalls. It only concerns itself with enabled firewalls.
Hence, if we disable them instead, ROM comes up again in the resume
sequence to make the same configurations. By keeping the firewalls
enabled, TIFS will save their context during suspend, and handle their
restoration during resume, thereby undoing anything ROM had done in
resume. This is neater and faster than TF-A itself handling the firewall
configuration again in resume.

Change-Id: I9ba7fa112a8d10f08f887fbb5a13e33177d60a80
Signed-off-by: T Pratham <t-pratham@ti.com>

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feat(k3low): re-configure firewalls for TI AM62L

In TI AM62L SoC, some of the firewalls are configured by ROM during
boot, or are at their default configurations. These firewalls are not
necessary a

feat(k3low): re-configure firewalls for TI AM62L

In TI AM62L SoC, some of the firewalls are configured by ROM during
boot, or are at their default configurations. These firewalls are not
necessary after the boot phase. For an HS-SE(SECURE ENFORCED) type
device, where the security goals are fully enforced, this causes
firewall exception when those regions are accessed from non-secure A53
core.

This commit adds changes to properly configure firewalls for AM62L SoC
initialization to remove the appropriate firewalls. A similar approach
is used for some other K3 TI SoCs, but in U-Boot. This code is based on
the U-Boot K3 firewall disabling code. Link:
https://github.com/u-boot/u-boot/blob/f9ffeec4bdcf1da655a0ffea482062adde78fee8/arch/arm/mach-k3/r5/common.c#L282

Change-Id: I6dd81d0544e181a58ce963ff9d724f465c764da0
Signed-off-by: T Pratham <t-pratham@ti.com>

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