This patch series adds stage-2 translation support for SMMUv3. It is
controlled by a new system property “arm-smmuv3.stage”.
- When set to “1”: Stage-1 only would be advertised and supported (default
behaviour)
- When set to “2”: Stage-2 only would be advertised and supported.
- Value “all” is reserved for nesting support. However it is not
implemented in this patch series (more about this in the end)

Features implemented in stage-2 are mostly synonymous with stage-1
- VMID16.
- Only AArch64 translation tables are supported.
- Stall is not supported.
- HTTU is not supported, SW is expected to maintain the Access flag.

To make it easy to support nesting, a new structure(SMMUS2Cfg) is
embedded within SMMUTransCfg, to hold stage-2 configuration.

TLBs were updated to support VMID, where when stage-2 is used ASID are
set to -1 and ignored and when stage-1 is used VMID is set to -1 and
ignored.
As only one stage is supported at a time at the moment, TLB will
represent IPA=>PA translation with proper attributes(granularity and
t0sz) parsed from STEs for stage-2, and will represent VA=>PA
translation with proper attributes parsed from the CDs for stage-1.

New commands where added that are used with stage-2
- CMD_TLBI_S12_VMALL: Invalidate all translations for a VMID.
- CMD_TLBI_S2_IPA: Invalidate stage-2 by VMID and IPA

These patches update OAS, as it used to be hardcoded to 44 bits, and
according to user manual ”6.3.6 SMMU_IDR5”, OAS must match the
system physical address size, so OAS is updated to be read from CPU
PARANGE.

This patch series can be used to run Linux pKVM SMMUv3 patches (currently on the list)
which controls stage-2 (from EL2) while providing a paravirtualized
interface the host(EL1)
https://lore.kernel.org/kvmarm/20230201125328.2186498-1-jean-philippe@linaro.org/

Looking forward, nesting is the next feature to go for, here are some
thoughts about this:

- TLB would require big changes for this, we can go either for a combined
implementation or per stage one. This would affect returns from PTW and
invalidation commands.

- Stage-1 data structures should be translated by stage-2 if enabled (as
context descriptors and ttb0/ttb1)

- Translated addresses from stage-1 should be translated by stage-2 if
enabled.

- Record faults should be separated between stage-1 (CD_R) and stage-2
(S2R).

- Some existing commands(as CMD_TLBI_S2_IPA, CMD_TLBI_NH_ASID …) would be
modified and some of those would be based on the design of the TLBs.

- Currently, VMID is ignored when stage-1 is used as it can’t be used with
stage-2. However when nesting is advertised VMID shouldn’t be ignored
even if stage-2 is bypassed.

Changes in v2:
-Collected Reviewed-by tags
-Add oas to SMMUS2Cfg, and use it in PTW
-Add stage member to to SMMUPTWEventInfo to differentiate stage-1 and
 stage-2 PTW faults
-Move stage-2 knob to the last patch
-Add all STE parsing in one patch
-Pares and use S2PS and S2ENDI
-Split S2AFF patch over PTW and STE patches.
-Fix TLB aliasing issue
-Renaming and refactoring and rewording commits.
-Populate OAS based on PARANGE
-Add checks for stage-1 only commands
-Update trace events to hold translation stage, vmid when possible
-Remove feature flags for supported stages as they were redundant with IDR0


Mostafa Saleh (11):
  hw/arm/smmuv3: Add missing fields for IDR0
  hw/arm/smmuv3: Update translation config to hold stage-2
  hw/arm/smmuv3: Refactor stage-1 PTW
  hw/arm/smmuv3: Add page table walk for stage-2
  hw/arm/smmuv3: Parse STE config for stage-2
  hw/arm/smmuv3: Make TLB lookup work for stage-2
  hw/arm/smmuv3: Add VMID to tlb tagging
  hw/arm/smmuv3: Add CMDs related to stage-2
  hw/arm/smmuv3: Add stage-2 support in iova notifier
  hw/arm/smmuv3: Populate OAS based on CPU PARANGE
  hw/arm/smmuv3: Add knob to choose translation stage and enable stage-2

 hw/arm/smmu-common.c         | 212 ++++++++++++++++++---
 hw/arm/smmu-internal.h       |  41 ++++
 hw/arm/smmuv3-internal.h     |  21 +--
 hw/arm/smmuv3.c              | 352 ++++++++++++++++++++++++++++++-----
 hw/arm/trace-events          |  14 +-
 include/hw/arm/smmu-common.h |  32 +++-
 include/hw/arm/smmuv3.h      |   4 +
 7 files changed, 577 insertions(+), 99 deletions(-)

-- 
2.39.2.637.g21b0678d19-goog