Re: [PATCH v3 00/52] xen/arm: Add Armv8-R64 MPU support to Xen - Part#1

[Ayan Kumar Halder <ayankuma@xxxxxxx>]

On 26/06/2023 04:33, Penny Zheng wrote:
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>
> So sorry for the long long wait before v3 serie, since I got sidetracked to
> a new high priority internal project for quite a time.
>
> The Armv8-R architecture profile was designed to support use cases
> that have a high sensitivity to deterministic execution. (e.g.
> Fuel Injection, Brake control, Drive trains, Motor control etc)
>
> Arm announced Armv8-R in 2013, it is the latest generation Arm
> architecture targeted at the Real-time profile. It introduces
> virtualization at the highest security level while retaining the
> Protected Memory System Architecture (PMSA) based on a Memory
> Protection Unit (MPU). In 2020, Arm announced Cortex-R82,
> which is the first Arm 64-bit Cortex-R processor based on Armv8-R64.
> The latest Armv8-R64 document can be found [1]. And the features of
> Armv8-R64 architecture:
>    - An exception model that is compatible with the Armv8-A model
>    - Virtualization with support for guest operating systems
>    - PMSA virtualization using MPUs In EL2.
>    - Adds support for the 64-bit A64 instruction set.
>    - Supports up to 48-bit physical addressing.
>    - Supports three Exception Levels (ELs)
>          - Secure EL2 - The Highest Privilege
>          - Secure EL1 - RichOS (MMU) or RTOS (MPU)
>          - Secure EL0 - Application Workloads
>   - Supports only a single Security state - Secure.
>   - MPU in EL1 & EL2 is configurable, MMU in EL1 is configurable.
>
> These patch series are implementing the Armv8-R64 MPU support
> for Xen, which are based on the discussion of
> "Proposal for Porting Xen to Armv8-R64 - DraftC" [2].
>
> We will implement the Armv8-R64 and MPU support in three stages:
> 1. Support to boot MMU domains on Armv8-R64 Xen.
> 2. Support to boot MPU domains on Armv8-R64 Xen.
> 3. SMP and other advanced features of Xen support on Armv8-R64.
>
> For having a overall undestanding for reviewers about MPU framework on Xen,
> we have introduced a large patch serie here, including 52 commits. At this
> stage, we could successfully boot a linux guest on FVP_BaseR_AEMv8R
> model[3].
>
> We will split these patches to several parts, this series is the
> part#1, v1 is in [4], the full PoC can be found in [5]. More software for
> Armv8-R64 can be found in [6];
>
> [1] https://developer.arm.com/documentation/ddi0600/latest
> [2] https://lists.xenproject.org/archives/html/xen-devel/2022-05/msg00643.html
> [3] 
> https://developer.arm.com/tools-and-software/simulation-models/fixed-virtual-platforms/arm-ecosystem-models
> [4] https://lists.xenproject.org/archives/html/xen-devel/2022-11/msg00289.html
> [5] https://gitlab.com/xen-project/people/weic/xen/-/tree/integration/mpu_v3
> [6] https://armv8r64-refstack.docs.arm.com/en/v5.0/
>
> Penny Zheng (41):
>    xen/arm: introduce CONFIG_HAS_MMU
>    xen/arm: mmu: fold FIXMAP into MMU system
>    xen/mmu: extract early uart mapping from setup_fixmap
>    xen/mmu: move MMU-specific setup_mm to mmu/setup.c
>    xen: make VMAP only support in MMU system
>    xen/mmu: relocate copy_from_paddr into setup.c
>    xen/arm: do not give memory back to static heap
>    xen/arm: only map the init text section RW in free_init_memory
>    xen/arm: switch to use ioremap_xxx in common file
>    xen/mmu: move MMU specific P2M code to mmu/p2m.c and mmu/p2m.h
>    xen: introduce CONFIG_HAS_PAGING_MEMPOOL
>    xen/mmu: enable SMMU subsystem only in MMU
>    xen/mpu: build up start-of-day Xen MPU memory region map
>    xen/mpu: introduce helpers for MPU enablement
>    xen/mpu: map early uart when earlyprintk on
>    xen/mpu: introduce setup_mm_mappings
>    xen/mpu: plump virt/maddr conversion in MPU system
>    xen/mpu: introduce a pair helper
>      read_protection_region()/write_protection_region()
>    xen/mpu: populate a new region in Xen MPU mapping table
>    xen/mpu: make early_fdt_map support in MPU systems
>    xen/mpu: implement MPU version of setup_mm in mpu/setup.c
>    xen/mpu: initialize frametable in MPU system
>    xen/mpu: destroy an existing entry in Xen MPU memory mapping table
>    xen/arm: map static memory on demand
>    xen/mpu: implememt ioremap_xxx in MPU
>    xen/mpu: implement MPU version of copy_from_paddr
>    xen/mpu: map domain page in MPU system
>    xen/mpu: support free_init_memory in MPU system
>    xen/mpu: implement remove_early_mappings in MPU system
>    xen/mpu: Use secure hypervisor timer in MPU system
>    xen/mpu: implement setup_virt_paging for MPU system
>    xen/mpu: configure VSTCR_EL2 in MPU system
>    xen/mpu: P2M initialization in MPU system
>    xen/mpu: insert an new entry into guest physmap in MPU system
>    xen/mpu: look up entry in p2m table
>    xen/mpu: support vcpu context switch in MPU system
>    xen/mpu: enable MMIO region trap in MPU system
>    xen/mpu: enable device passthrough in MPU system
>    xen/mpu: dump debug message in MPU system
>    xen/mpu: create stubs of function/variables for UNSUPPORTED features
>    xen/arm: add Kconfig option CONFIG_HAS_MPU to enable MPU system
>      support
>
> Wei Chen (11):
>    xen/arm: remove xen_phys_start and xenheap_phys_end from config.h
>    xen/arm: make ARM_EFI selectable for Arm64
>    xen/arm: add an option to define Xen start address for Armv8-R
>    xen/arm: add .text.idmap in ld script for Xen identity map sections
>    xen/arm64: head: Introduce enable_boot_mmu and enable_runtime_mmu
>    xen/arm64: prepare for moving MMU related code from head.S
>    xen/arm64: move MMU related code from head.S to mmu/head.S
>    xen/arm: use PA == VA for EARLY_UART_VIRTUAL_ADDRESS on MPU systems
>    xen/arm: Move MMU related definitions from config.h to mmu/layout.h
>    xen/mmu: extract mmu-specific codes from mm.c/mm.h
>    xen/arm: create mpu/layout.h for MPU related address definitions
Hi All,

I had a look at the first 22 patches (which touch the MMU code) and I 
did not find anything which will impact the R52 work directly.
- Ayan

>   xen/arch/arm/Kconfig                     |   52 +-
>   xen/arch/arm/Kconfig.debug               |    7 +
>   xen/arch/arm/Makefile                    |   15 +-
>   xen/arch/arm/arm32/head.S                |    2 +-
>   xen/arch/arm/arm64/Makefile              |    7 +-
>   xen/arch/arm/arm64/head.S                |  472 +-----
>   xen/arch/arm/arm64/mmu/head.S            |  463 ++++++
>   xen/arch/arm/arm64/{ => mmu}/mm.c        |    7 +-
>   xen/arch/arm/arm64/mpu/head.S            |  255 ++++
>   xen/arch/arm/arm64/smpboot.c             |    6 +-
>   xen/arch/arm/bootfdt.c                   |    2 +-
>   xen/arch/arm/domain.c                    |    2 +
>   xen/arch/arm/domain_build.c              |    2 +
>   xen/arch/arm/include/asm/arm64/macros.h  |   51 +
>   xen/arch/arm/include/asm/arm64/mm.h      |    7 +-
>   xen/arch/arm/include/asm/arm64/mpu.h     |  140 ++
>   xen/arch/arm/include/asm/arm64/sysregs.h |   76 +
>   xen/arch/arm/include/asm/config.h        |  129 +-
>   xen/arch/arm/include/asm/cpufeature.h    |    7 +
>   xen/arch/arm/include/asm/early_printk.h  |   20 +
>   xen/arch/arm/include/asm/fixmap.h        |   31 +-
>   xen/arch/arm/include/asm/mm.h            |   79 +-
>   xen/arch/arm/include/asm/mmu/layout.h    |  141 ++
>   xen/arch/arm/include/asm/mmu/mm.h        |   54 +
>   xen/arch/arm/include/asm/mmu/p2m.h       |   18 +
>   xen/arch/arm/include/asm/mpu/layout.h    |   32 +
>   xen/arch/arm/include/asm/mpu/mm.h        |   36 +
>   xen/arch/arm/include/asm/mpu/p2m.h       |   18 +
>   xen/arch/arm/include/asm/p2m.h           |   48 +-
>   xen/arch/arm/include/asm/page.h          |   46 +-
>   xen/arch/arm/include/asm/processor.h     |   14 +
>   xen/arch/arm/include/asm/setup.h         |   16 +-
>   xen/arch/arm/kernel.c                    |   42 +-
>   xen/arch/arm/mm.c                        | 1160 +-------------
>   xen/arch/arm/mmu/mm.c                    | 1133 ++++++++++++++
>   xen/arch/arm/mmu/p2m.c                   | 1612 +++++++++++++++++++
>   xen/arch/arm/mmu/setup.c                 |  379 +++++
>   xen/arch/arm/mpu/domain_page.c           |   68 +
>   xen/arch/arm/mpu/mm.c                    |  959 ++++++++++++
>   xen/arch/arm/mpu/p2m.c                   |  518 +++++++
>   xen/arch/arm/mpu/setup.c                 |  102 ++
>   xen/arch/arm/p2m.c                       | 1782 ++--------------------
>   xen/arch/arm/platforms/Kconfig           |    8 +-
>   xen/arch/arm/setup.c                     |  388 +----
>   xen/arch/arm/smpboot.c                   |    6 +-
>   xen/arch/arm/traps.c                     |   97 +-
>   xen/arch/arm/xen.lds.S                   |    6 +-
>   xen/arch/x86/Kconfig                     |    2 +
>   xen/arch/x86/setup.c                     |    2 +
>   xen/common/Kconfig                       |    8 +
>   xen/common/Makefile                      |    2 +-
>   xen/common/domctl.c                      |    2 +
>   xen/common/vmap.c                        |    7 +
>   xen/drivers/passthrough/Kconfig          |    3 +-
>   xen/include/xen/vmap.h                   |   11 +-
>   55 files changed, 6730 insertions(+), 3822 deletions(-)
>   create mode 100644 xen/arch/arm/arm64/mmu/head.S
>   rename xen/arch/arm/arm64/{ => mmu}/mm.c (97%)
>   create mode 100644 xen/arch/arm/arm64/mpu/head.S
>   create mode 100644 xen/arch/arm/include/asm/arm64/mpu.h
>   create mode 100644 xen/arch/arm/include/asm/mmu/layout.h
>   create mode 100644 xen/arch/arm/include/asm/mmu/mm.h
>   create mode 100644 xen/arch/arm/include/asm/mmu/p2m.h
>   create mode 100644 xen/arch/arm/include/asm/mpu/layout.h
>   create mode 100644 xen/arch/arm/include/asm/mpu/mm.h
>   create mode 100644 xen/arch/arm/include/asm/mpu/p2m.h
>   create mode 100644 xen/arch/arm/mmu/mm.c
>   create mode 100644 xen/arch/arm/mmu/p2m.c
>   create mode 100644 xen/arch/arm/mmu/setup.c
>   create mode 100644 xen/arch/arm/mpu/domain_page.c
>   create mode 100644 xen/arch/arm/mpu/mm.c
>   create mode 100644 xen/arch/arm/mpu/p2m.c
>   create mode 100644 xen/arch/arm/mpu/setup.c
>
> --
> 2.25.1