Add a SysBus model for the 64 K230 Function IO configuration registers
documented by the K230 Technical Reference Manual. The model retains the
writable configuration fields needed by the SDK U-Boot and Linux
read-modify-write paths.

The series adds the device model, wires it into the K230 SoC at
0x91105000, and adds qtest coverage.

Changes in v2:
- Split the device model, SoC wiring, and qtest coverage into separate
  patches.
- Removed redundant MMIO bounds, access-size, and alignment checks.
- Limited register storage to the 64 documented Function IO registers.
- Applied the documented 0x00003fff writable mask.
- Treated offsets 0x100 through 0x7ff as reserved.
- Added tests for write masking, read-modify-write accesses, IO63,
  reserved offsets, and system reset.

Tested with:
- qtest-riscv64/k230-iomux-test
- qtest-riscv64/k230-wdt-test
- SDK U-Boot smoke test, reaching the K230 prompt

v1:
https://lore.kernel.org/qemu-devel/20260710041845.67170-1-flamboyant.h.01@gmail.com/

Kangjie Huang (3):
  hw/misc/k230_iomux: add Kendryte K230 IOMUX model
  hw/riscv/k230: wire up the IOMUX device
  tests/qtest: add test for K230 IOMUX

 docs/system/riscv/k230.rst    |   1 +
 hw/misc/Kconfig               |   3 +
 hw/misc/k230_iomux.c          | 124 +++++++++++++++++++++++++++
 hw/misc/meson.build           |   2 +
 hw/misc/trace-events          |   4 +
 hw/riscv/Kconfig              |   1 +
 hw/riscv/k230.c               |  11 ++-
 include/hw/misc/k230_iomux.h  |  34 ++++++++
 include/hw/riscv/k230.h       |   2 +
 tests/qtest/k230-iomux-test.c | 155 ++++++++++++++++++++++++++++++++++
 tests/qtest/meson.build       |   5 +-
 11 files changed, 338 insertions(+), 4 deletions(-)
 create mode 100644 hw/misc/k230_iomux.c
 create mode 100644 include/hw/misc/k230_iomux.h
 create mode 100644 tests/qtest/k230-iomux-test.c

-- 
2.43.0