[PATCH v4 0/8] Move parts of Arm's Dom0less to common code

[Oleksii Kurochko <oleksii.kurochko@gmail.com>]

Some parts of Arm's Dom0less solution could be moved to common code as they are
not truly Arm-specific.

Most of the code is moved as is, with only minor changes introduced to provide
abstractions that hide Arm-specific details, while maintaining functional
equivalence with original Arm's code.

There are several open questions:
1. The u64 and u32 types are widely used in the code where device tree
   functionality is implemented because these types are used in device tree
   function arguments.
   Should this be reworked to use uint32_t and uint64_t instead? If so, will it
   also be necessary to change the type of variables passed to dt-related
   functions, or should the argument types of device tree functions be updated
   too? For example:
   ```
    u64 mem;
    ...
    rc = dt_property_read_u64(node, "memory", &mem);
   ```
   where dt_property_read_u64 is declared as:
     bool dt_property_read_u64(... , u64 *out_value);
2. Instead of providing init_intc_phandle() (see the patch: [1]), perhaps it
   would be better to add a for loop in domain_handle_dtb_bootmodule()?
   Something like:
   ```
    bool is_intc_phandle_inited = false;
    for ( unsigned int i = 0; i < ARRAY_SIZE(intc_names_array); i++ )
    {
        if ( dt_node_cmp(name, intc_names_array[i]) == 0 )
        {
            uint32_t phandle_intc = fdt_get_phandle(pfdt, node_next);

            if ( phandle_intc != 0 )
                kinfo->phandle_intc = phandle_intc;

            is_intc_phandle_inited = true;
            break;
        }
    }

    if ( is_intc_phandle_inited ) continue;
  ```

CI's test for the current patch series:
  https://gitlab.com/xen-project/people/olkur/xen/-/pipelines/1801183107

---
Changes in v4:
 - Drop item 3 from the cover letter message as it was decided to rename
   dom0less to predefined domains separately.
 - Update the link with results of CI testing.
 - All other changes please look in the specific patch.
---
Changes in v3:
- Rebase on top of current staging and fixing merge conflicts.
- Ingrate changes done in the commit:
    "xen/arm: dom0less delay xenstore initialization"
- All other changes please look in the specific patch.
- Update cover letter message.
---
Changes in v2:
- Update cover letter message.
- Rebase on top of the current staging.
- Drop patches:
   - asm-generic: move Arm's static-memory.h to asm-generic
   - asm-generic: move Arm's static-shmem.h to asm-generic
  as in the nearest future there is no real users of STATIC_MEMORY and
  STATIC_SHMEM.
- Add new cleanup patch:
  [PATCH v2 1/8] xen/arm: drop declaration of handle_device_interrupts()
- All other changes are patch specific. Please check them seprately for each
  patch
---

Oleksii Kurochko (8):
  xen/arm: drop declaration of handle_device_interrupts()
  xen/common: dom0less: make some parts of Arm's CONFIG_DOM0LESS common
  asm-generic: move parts of Arm's asm/kernel.h to common code
  arm/static-shmem.h: drop inclusion of asm/setup.h
  asm-generic: move some parts of Arm's domain_build.h to common
  xen/common: dom0less: introduce common kernel.c
  xen/common: dom0less: introduce common domain-build.c
  xen/common: dom0less: introduce common dom0less-build.c

 xen/arch/arm/Kconfig                      |   10 +-
 xen/arch/arm/acpi/domain_build.c          |    3 +-
 xen/arch/arm/dom0less-build.c             | 1078 ++-------------------
 xen/arch/arm/domain_build.c               |  410 +-------
 xen/arch/arm/include/asm/Makefile         |    1 +
 xen/arch/arm/include/asm/dom0less-build.h |   34 -
 xen/arch/arm/include/asm/domain_build.h   |   32 +-
 xen/arch/arm/include/asm/kernel.h         |  123 +--
 xen/arch/arm/include/asm/static-memory.h  |    2 +-
 xen/arch/arm/include/asm/static-shmem.h   |    3 +-
 xen/arch/arm/kernel.c                     |  235 +----
 xen/arch/arm/static-memory.c              |    1 +
 xen/arch/arm/static-shmem.c               |    2 +
 xen/common/Kconfig                        |   15 +
 xen/common/device-tree/Makefile           |    3 +
 xen/common/device-tree/dom0less-build.c   | 1002 +++++++++++++++++++
 xen/common/device-tree/domain-build.c     |  395 ++++++++
 xen/common/device-tree/dt-overlay.c       |    4 +-
 xen/common/device-tree/kernel.c           |  242 +++++
 xen/include/asm-generic/dom0less-build.h  |   84 ++
 xen/include/xen/fdt-domain-build.h        |   75 ++
 xen/include/xen/fdt-kernel.h              |  145 +++
 22 files changed, 2094 insertions(+), 1805 deletions(-)
 delete mode 100644 xen/arch/arm/include/asm/dom0less-build.h
 create mode 100644 xen/common/device-tree/dom0less-build.c
 create mode 100644 xen/common/device-tree/domain-build.c
 create mode 100644 xen/common/device-tree/kernel.c
 create mode 100644 xen/include/asm-generic/dom0less-build.h
 create mode 100644 xen/include/xen/fdt-domain-build.h
 create mode 100644 xen/include/xen/fdt-kernel.h

-- 
2.49.0