From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
Implement pv_kick with SBI implementation, and add SBI_EXT_PVLOCK
extension detection.
Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
Signed-off-by: Guo Ren <guoren@xxxxxxxxxx>
---
arch/riscv/include/asm/sbi.h | 6 ++++++
arch/riscv/kernel/qspinlock_paravirt.c | 7 ++++++-
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index e0233b3d7a5f..3533f8d4f3e2 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -30,6 +30,7 @@ enum sbi_ext_id {
SBI_EXT_HSM = 0x48534D,
SBI_EXT_SRST = 0x53525354,
SBI_EXT_PMU = 0x504D55,
+ SBI_EXT_PVLOCK = 0xAB0401,
/* Experimentals extensions must lie within this range */
SBI_EXT_EXPERIMENTAL_START = 0x08000000,
@@ -243,6 +244,11 @@ enum sbi_pmu_ctr_type {
/* Flags defined for counter stop function */
#define SBI_PMU_STOP_FLAG_RESET (1 << 0)
+/* SBI PVLOCK (kick cpu out of wfi) */
+enum sbi_ext_pvlock_fid {
+ SBI_EXT_PVLOCK_KICK_CPU = 0,
+};
+
#define SBI_SPEC_VERSION_DEFAULT 0x1
#define SBI_SPEC_VERSION_MAJOR_SHIFT 24
#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f
diff --git a/arch/riscv/kernel/qspinlock_paravirt.c b/arch/riscv/kernel/qspinlock_paravirt.c
index a0ad4657f437..571626f350be 100644
--- a/arch/riscv/kernel/qspinlock_paravirt.c
+++ b/arch/riscv/kernel/qspinlock_paravirt.c
@@ -11,6 +11,8 @@
void pv_kick(int cpu)
{
+ sbi_ecall(SBI_EXT_PVLOCK, SBI_EXT_PVLOCK_KICK_CPU,
+ cpuid_to_hartid_map(cpu), 0, 0, 0, 0, 0);
return;
}
@@ -25,7 +27,7 @@ void pv_wait(u8 *ptr, u8 val)
if (READ_ONCE(*ptr) != val)
goto out;
- /* wait_for_interrupt(); */
+ wait_for_interrupt();
out:
local_irq_restore(flags);
}
@@ -62,6 +64,9 @@ void __init pv_qspinlock_init(void)
if(sbi_get_firmware_id() != SBI_EXT_BASE_IMPL_ID_KVM)
return;
+ if (!sbi_probe_extension(SBI_EXT_PVLOCK))
+ return;
+
pr_info("PV qspinlocks enabled\n");
__pv_init_lock_hash();
--
2.36.1
