Files
linux-stable-mirror/arch/loongarch/kvm
Bibo Mao 4d9b0ea629 LoongArch: KVM: Add delay until timer interrupt injected
commit d3c9515e4f upstream.

When timer is fired in oneshot mode, CSR.TVAL will stop with value -1
rather than 0. However when the register CSR.TVAL is restored, it will
continue to count down rather than stop there.

Now the method is to write 0 to CSR.TVAL, wait to count down for 1 cycle
at least, which is 10ns with a timer freq 100MHz, and then retore timer
interrupt status. Here add 2 cycles delay to assure that timer interrupt
is injected.

With this patch, timer selftest case passes to run always.

Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-24 10:35:58 +01:00
..