hw/riscv: Initial support for BOSC's Xiangshan Kunminghu FPGA prototype

This implementation provides emulation for the Xiangshan Kunminghu
FPGA prototype platform, including support for UART, CLINT, IMSIC,
and APLIC devices. More details can be found at
https://github.com/OpenXiangShan/XiangShan

Signed-off-by: qinshaoqing <qinshaoqing@bosc.ac.cn>
Signed-off-by: Yang Wang <wangyang@bosc.ac.cn>
Signed-off-by: Yu Hu <819258943@qq.com>
Signed-off-by: Ran Wang <wangran@bosc.ac.cn>
Signed-off-by: Borong Huang <3543977024@qq.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20250617074222.17618-1-wangran@bosc.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

docs/system/riscv/xiangshan-kunminghu.rst

@@ -0,0 +1,39 @@
+BOSC Xiangshan Kunminghu FPGA prototype platform (``xiangshan-kunminghu``)
+==========================================================================
+The ``xiangshan-kunminghu`` machine is compatible with our FPGA prototype
+platform.
+
+XiangShan is an open-source high-performance RISC-V processor project.
+The third generation processor is called Kunminghu. Kunminghu is a 64-bit
+RV64GCBSUHV processor core. More information can be found in our Github
+repository:
+https://github.com/OpenXiangShan/XiangShan
+
+Supported devices
+-----------------
+The ``xiangshan-kunminghu`` machine supports the following devices:
+
+* Up to 16 xiangshan-kunminghu cores
+* Core Local Interruptor (CLINT)
+* Incoming MSI Controller (IMSIC)
+* Advanced Platform-Level Interrupt Controller (APLIC)
+* 1 UART
+
+Boot options
+------------
+The ``xiangshan-kunminghu`` machine can start using the standard ``-bios``
+functionality for loading the boot image. You need to compile and link
+the firmware, kernel, and Device Tree (FDT) into a single binary file,
+such as ``fw_payload.bin``.
+
+Running
+-------
+Below is an example command line for running the ``xiangshan-kunminghu``
+machine:
+
+.. code-block:: bash
+
+   $ qemu-system-riscv64 -machine xiangshan-kunminghu \
+      -smp 16 -m 16G \
+      -bios path/to/opensbi/platform/generic/firmware/fw_payload.bin \
+      -nographic

docs/system/target-riscv.rst

@@ -71,6 +71,7 @@ undocumented; you can get a complete list by running
    riscv/shakti-c
    riscv/sifive_u
    riscv/virt
+   riscv/xiangshan-kunminghu
 
 RISC-V CPU firmware
 -------------------