kumquat-buildroot/board/spike/riscv64
Julien Olivain 38c581b05c configs/spike_riscv64: bump kernel to 6.1.14
Linux Kernel 6.1 now being officially promoted to be a LTS, this
commit bump the kernel version of this defconfig to 6.1.14.

A Kernel config fragment "linux.fragment" is now needed as the kernel
no longer enable SBI v0.1 support and the earlycon RISC-V SBI in its
riscv arch defconfig. See [1] [2].

The Spike riscv-isa-sim was updated upstream accordingly [3].

In order to keep a smooth transition, this kernel config fragment
re-enable those options to make sure this kernel will work with
both old Spike versions (not including commit [3] like the v1.1.0
currently included in Buildroot), and newer versions. This commit
was also successfully tested with riscv-isa-sim at commit
0d1a48c0c0.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6f562570b9c5d6a3e30d87aec60a9d8f22a3203c
[2] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3938d5a2f9369d1ebd56320629fed395ce327e9c
[3] 191634d285

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
2023-03-12 18:45:08 +01:00
..
linux.fragment configs/spike_riscv64: bump kernel to 6.1.14 2023-03-12 18:45:08 +01:00
readme.txt
start.sh

Linux on Spike RISC-V ISA simulator
===================================

This configuration provides a minimal working setup to run a Linux
kernel in the Spike RISC-V ISA simulator.

The Spike ISA simulator can be an interresting alternative to Qemu, in
some specific cases. For example: simulating new instructions (see [1]),
simulating riscv-openocd/gdb debug sessions (see [2], [3]), or
generating an accurate per-instruction log of execution (see
riscv-isa-sim spike -l option)...

To run Buildroot Linux in Spike, use the commands:

    make spike_riscv64_defconfig
    make
    ./board/spike/riscv64/start.sh

The boot is made with the standard RISC-V OpenSBI boot loader. In
order to keep the simulation simple, the rootfs is passed as an initrd
ramfs.

Note: at the time of this writing, Spike v1.1.0 and OpenSBI v1.0 does
not support console input emulation for 32bit RISC-V systems. A 32bit
Linux system can boot and reach the login, but it's not possible to
login. See [4].


[1].
https://github.com/riscv-software-src/riscv-isa-sim/tree/v1.1.0#simulating-a-new-instruction

[2].
https://github.com/riscv-software-src/riscv-isa-sim/tree/v1.1.0#debugging-with-gdb

[3].
https://github.com/riscv/riscv-openocd

[4].
https://github.com/riscv-software-src/opensbi/blob/v1.0/lib/utils/sys/htif.c#L127