This patch series adds SMP support for RISC-V to U-Boot. It allows U-Boot to run on multi-hart systems and will boot images passed to bootm on all harts. The bootm command is currently the only one that will boot images on all harts, bootefi is not yet supported.
The patches have been successfully tested on both QEMU (machine and supervisor mode) and the HiFive Unleashed board [1] (supervisor mode), using BBL and OpenSBI. Mainline QEMU requires two patches [2, 3] to run in this configuration. I will send a follow-up patch to enable SMP support on the HiFive Unleashed board.
[1]: https://patchwork.ozlabs.org/project/uboot/list/?series=91125 [2]: https://patchwork.ozlabs.org/patch/1039493/ [3]: https://patchwork.ozlabs.org/patch/1039082/
Lukas Auer (7): riscv: add infrastructure for calling functions on other harts riscv: import the supervisor binary interface header file riscv: implement IPI platform functions using SBI riscv: delay initialization of caches and debug UART riscv: add support for multi-hart systems riscv: boot images passed to bootm on all harts riscv: qemu: enable SMP
arch/riscv/Kconfig | 36 +++++++++ arch/riscv/cpu/start.S | 116 +++++++++++++++++++++++++-- arch/riscv/include/asm/csr.h | 1 + arch/riscv/include/asm/global_data.h | 5 ++ arch/riscv/include/asm/sbi.h | 94 ++++++++++++++++++++++ arch/riscv/include/asm/smp.h | 53 ++++++++++++ arch/riscv/lib/Makefile | 2 + arch/riscv/lib/bootm.c | 13 ++- arch/riscv/lib/sbi_ipi.c | 25 ++++++ arch/riscv/lib/smp.c | 110 +++++++++++++++++++++++++ board/emulation/qemu-riscv/Kconfig | 1 + 11 files changed, 447 insertions(+), 9 deletions(-) create mode 100644 arch/riscv/include/asm/sbi.h create mode 100644 arch/riscv/include/asm/smp.h create mode 100644 arch/riscv/lib/sbi_ipi.c create mode 100644 arch/riscv/lib/smp.c