[PATCH 0/5] virt: Add Bao hypervisor IPC and I/O dispatcher drivers

[joaopeixoto at osyx.tech]

From: João Peixoto <joaopeixoto at osyx.tech>

This series introduces support for the Bao hypervisor guest-side drivers
under drivers/virt/bao and the associated Device Tree bindings, UAPI,
and MAINTAINERS entries.

Bao is a lightweight static-partitioning hypervisor for embedded and
safety-critical systems. This series adds:
- The Bao IPC shared memory driver, which enables Linux guests to
  communicate with each other through shared memory regions.
- The Bao I/O Dispatcher driver, which allows Bao's VMs to share I/O
  devices using device paravirtualization (VirtIO).

Patch overview:

1. dt-bindings: Add Bao IPC shared memory driver binding
   - Provides a standardized DT description for Bao IPC shared memory
     devices used for inter-VM communication.

2. virt: add Bao IPC shared memory driver
   - Character device driver that maps shared-memory regions and
     communicates with the hypervisor via architecture-specific hypercalls
     (SMC/HVC on ARM, SBI ecall on RISC-V).

3. dt-bindings: Add Bao I/O dispatcher driver binding
   - DT binding for the Bao I/O Dispatcher, describing memory regions,
     interrupts, and compatible strings for backend VMs.

4. virt: add Bao I/O dispatcher driver
   - Implements the I/O Dispatcher kernel module bridging Bao Remote I/O
     with VirtIO backend devices.
   - Includes architecture-specific headers for ARM, ARM64, and RISC-V,
     driver framework files, UAPI headers, Kconfig/Makefile integration,
     and ioctl documentation.

5. MAINTAINERS: Add entries for Bao hypervisor drivers
   - Registers maintainers for all Bao hypervisor components to ensure
     proper kernel review and notifications.

This series has been validated on Linux guests running under Bao hypervisor,
ensuring correct initialization, read/write operations for IPC shared
memory, and proper I/O Dispatcher functionality for backend VMs.

Feedback and review from maintainers of virtualization, architecture-specific
code (ARM, ARM64, RISC-V), Device Tree bindings, and UAPI are welcome.

João Peixoto (5):
  dt-bindings: Add Bao IPC shared memory driver binding
  virt: add Bao IPC shared memory driver
  dt-bindings: Add Bao I/O dispatcher driver binding
  virt: add Bao I/O dispatcher driver
  MAINTAINERS: Add entries for Bao hypervisor drivers, headers, and DT
    bindings

 .../bindings/bao/io-dispatcher.yaml           |  67 +++
 .../devicetree/bindings/bao/ipcshmem.yaml     |  99 ++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 .../userspace-api/ioctl/ioctl-number.rst      |   2 +
 MAINTAINERS                                   |  12 +
 arch/arm/include/asm/bao.h                    |  62 ++
 arch/arm64/include/asm/bao.h                  |  62 ++
 arch/riscv/include/asm/bao.h                  |  61 ++
 drivers/virt/Kconfig                          |   2 +
 drivers/virt/Makefile                         |   2 +
 drivers/virt/bao/Kconfig                      |   5 +
 drivers/virt/bao/Makefile                     |   4 +
 drivers/virt/bao/io-dispatcher/Kconfig        |  16 +
 drivers/virt/bao/io-dispatcher/Makefile       |   4 +
 drivers/virt/bao/io-dispatcher/bao_drv.h      | 386 +++++++++++++
 drivers/virt/bao/io-dispatcher/dm.c           | 330 +++++++++++
 drivers/virt/bao/io-dispatcher/driver.c       | 348 +++++++++++
 drivers/virt/bao/io-dispatcher/hypercall.h    |  30 +
 drivers/virt/bao/io-dispatcher/intc.c         |  68 +++
 drivers/virt/bao/io-dispatcher/io_client.c    | 435 ++++++++++++++
 .../virt/bao/io-dispatcher/io_dispatcher.c    | 207 +++++++
 drivers/virt/bao/io-dispatcher/ioctls.c       | 145 +++++
 drivers/virt/bao/io-dispatcher/ioeventfd.c    | 336 +++++++++++
 drivers/virt/bao/io-dispatcher/irqfd.c        | 341 +++++++++++
 drivers/virt/bao/ipcshmem/Kconfig             |   9 +
 drivers/virt/bao/ipcshmem/Makefile            |   3 +
 drivers/virt/bao/ipcshmem/ipcshmem.c          | 539 ++++++++++++++++++
 include/uapi/linux/bao.h                      | 124 ++++
 28 files changed, 3701 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/bao/io-dispatcher.yaml
 create mode 100644 Documentation/devicetree/bindings/bao/ipcshmem.yaml
 create mode 100644 arch/arm/include/asm/bao.h
 create mode 100644 arch/arm64/include/asm/bao.h
 create mode 100644 arch/riscv/include/asm/bao.h
 create mode 100644 drivers/virt/bao/Kconfig
 create mode 100644 drivers/virt/bao/Makefile
 create mode 100644 drivers/virt/bao/io-dispatcher/Kconfig
 create mode 100644 drivers/virt/bao/io-dispatcher/Makefile
 create mode 100644 drivers/virt/bao/io-dispatcher/bao_drv.h
 create mode 100644 drivers/virt/bao/io-dispatcher/dm.c
 create mode 100644 drivers/virt/bao/io-dispatcher/driver.c
 create mode 100644 drivers/virt/bao/io-dispatcher/hypercall.h
 create mode 100644 drivers/virt/bao/io-dispatcher/intc.c
 create mode 100644 drivers/virt/bao/io-dispatcher/io_client.c
 create mode 100644 drivers/virt/bao/io-dispatcher/io_dispatcher.c
 create mode 100644 drivers/virt/bao/io-dispatcher/ioctls.c
 create mode 100644 drivers/virt/bao/io-dispatcher/ioeventfd.c
 create mode 100644 drivers/virt/bao/io-dispatcher/irqfd.c
 create mode 100644 drivers/virt/bao/ipcshmem/Kconfig
 create mode 100644 drivers/virt/bao/ipcshmem/Makefile
 create mode 100644 drivers/virt/bao/ipcshmem/ipcshmem.c
 create mode 100644 include/uapi/linux/bao.h

-- 
2.43.0