docs/system/target-riscv.rst

1 .. _RISC-V-System-emulator:
3 RISC-V System emulator
6 QEMU can emulate both 32-bit and 64-bit RISC-V CPUs. Use the
7 ``qemu-system-riscv64`` executable to simulate a 64-bit RISC-V machine,
8 ``qemu-system-riscv32`` executable to simulate a 32-bit RISC-V machine.
10 QEMU has generally good support for RISC-V guests. It has support for
12 RISC-V hardware is much more widely varying than x86 hardware. RISC-V
13 CPUs are generally built into "system-on-chip" (SoC) designs created by
23 ----------------------
25 For QEMU's RISC-V system emulation, you must specify which board
26 model you want to use with the ``-M`` or ``--machine`` option;
27 there is no default.
29 Because RISC-V systems differ so much and in fundamental ways, typically
30 operating system or firmware images intended to run on one machine
31 will not run at all on any other. This is often surprising for new
36 If you already have a system image or a kernel that works on hardware
38 in its ``-machine help`` output. If it is listed, then you can probably
40 will almost certainly not boot on QEMU. (You might be able to
42 boots on a system that QEMU does emulate.)
49 need to compile Linux with a suitable configuration for running on
51 large amounts of RAM. It also supports 64-bit CPUs.
53 Board-specific documentation
54 ----------------------------
56 Unfortunately many of the RISC-V boards QEMU supports are currently
58 ``qemu-system-riscv64 --machine help``, or
59 ``qemu-system-riscv32 --machine help``.
69    riscv/microblaze-v-generic
70    riscv/microchip-icicle-kit
71    riscv/shakti-c
75 RISC-V CPU firmware
76 -------------------
81 * ``-bios default``
83 This is the default behaviour if no ``-bios`` option is included. This option
84 will load the default OpenSBI firmware automatically. The firmware is included
86 do is specify the kernel they want to boot with the ``-kernel`` option
88 * ``-bios none``
93 * ``-bios <file>``