dev-arm: Rewrite SMMUv3 Commands

This patch is rewriting the SMMUv3::processCommand method for the
following reasons:

* Command names were not matching spec
* Command encoding/opcode was wrong

The patch is not adding any new command: there is still a subset of
unimplemented commands; those are:

* CMD_TLBI_EL3_ALL
* CMD_TLBI_EL3_VA
* CMD_TLBI_EL2_ALL
* CMD_TLBI_EL2_VA
* CMD_TLBI_EL2_VAA
* CMD_TLBI_EL2_ASID

which require StreamWorld support, and

* CMD_ATC_INV
* CMD_PRI_RESP
* CMD_RESUME
* CMD_STALL_TERM

which require in sequence: ATS, PRI, Stall Model support

Change-Id: Ia2dd47b5588738402d9584a00cfc88c94c253ad0
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Michiel van Tol <michiel.vantol@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19668
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm: Define enum masks for SMMU_CR0 register

The configuration register is a vital register in the SMMU, and using
enum masks will make the code more readable/understandable

Change-Id: Ia117db56c457fe876ae38be391c386e502f34384
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Michiel Van Tol <michiel.vantol@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19632
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm: Fix SMMUv3 ContextDescriptor pointer shift

The context descriptor pointer in the STE starts at the sixth LSB

Change-Id: Ifa346b350785b788e9d1e093b662cb26433adfb8
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Christo Smallwood <christo.smallwood@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19469
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm: Remove un-needed Q_CONS_PROD_MASK macro

Change-Id: I858d7eea088bbdd2dc12123e21e59991c896597f
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Michiel Van Tol <michiel.vantol@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19310
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm: Implement a SMMUv3 model

This is an implementation of the SMMUv3 architecture.

What can it do?
- Single-stage and nested translation with 4k or 64k granule. 16k would
be straightforward to add.
- Large pages are supported.
- Works with any gem5 device as long as it is issuing packets with a
valid (Sub)StreamId

What it can't do?
- Fragment stage 1 page when the underlying stage 2 page is smaller. S1
page size > S2 page size is not supported
- Invalidations take zero time. This wouldn't be hard to fix.
- Checkpointing is not supported
- Stall/resume for faulting transactions is not supported

Additional contributors:
- Michiel W. van Tol <Michiel.VanTol@arm.com>
- Giacomo Travaglini <giacomo.travaglini@arm.com>

Change-Id: Ibc606fccd9199b2c1ba739c6335c846ffaa4d564
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19008
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>