LOONGARCH_CSR_ISR0
old = kvm_read_hw_gcsr(LOONGARCH_CSR_ISR0);
kvm_write_hw_gcsr(LOONGARCH_CSR_ISR0, vector[0] | old);
set_gcsr_hw_flag(LOONGARCH_CSR_ISR0);
kvm_restore_hw_gcsr(csr, LOONGARCH_CSR_ISR0);
kvm_save_hw_gcsr(csr, LOONGARCH_CSR_ISR0);
isr = csr_read(LOONGARCH_CSR_ISR0);