From: Michael Clark <m...@sifive.com> This effectively changes riscv_cpu_update_mip from edge to level. i.e. cpu_interrupt or cpu_reset_interrupt are called regardless of the current interrupt level.
Fixes WFI doesn't return when a IPI is issued: - https://github.com/riscv/riscv-qemu/issues/132 To test: 1) Apply RISC-V Linux CPU hotplug patch: - http://lists.infradead.org/pipermail/linux-riscv/2018-May/000603.html 2) Enable CONFIG_CPU_HOTPLUG in linux .config 3) Try to offline and online cpus: echo 1 > /sys/devices/system/cpu/cpu2/online echo 0 > /sys/devices/system/cpu/cpu2/online echo 1 > /sys/devices/system/cpu/cpu2/online Reported-by: Atish Patra <atish...@gmail.com> Cc: Atish Patra <atish...@gmail.com> Cc: Alistair Francis <alistair.fran...@wdc.com> Signed-off-by: Michael Clark <m...@sifive.com> Signed-off-by: Alistair Francis <alistair.fran...@wdc.com> --- target/riscv/cpu_helper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 555756d40c..073bdcfe74 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -95,9 +95,9 @@ uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value) cmp = atomic_cmpxchg(&env->mip, old, new); } while (old != cmp); - if (new && !old) { + if (new) { cpu_interrupt(CPU(cpu), CPU_INTERRUPT_HARD); - } else if (!new && old) { + } else { cpu_reset_interrupt(CPU(cpu), CPU_INTERRUPT_HARD); } -- 2.20.1
