1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/hardirq.h> 3 4 #include <asm/x86_init.h> 5 6 #include <xen/interface/xen.h> 7 #include <xen/interface/sched.h> 8 #include <xen/interface/vcpu.h> 9 #include <xen/features.h> 10 #include <xen/events.h> 11 12 #include <asm/xen/hypercall.h> 13 #include <asm/xen/hypervisor.h> 14 15 #include "xen-ops.h" 16 17 /* 18 * Force a proper event-channel callback from Xen after clearing the 19 * callback mask. We do this in a very simple manner, by making a call 20 * down into Xen. The pending flag will be checked by Xen on return. 21 */ 22 noinstr void xen_force_evtchn_callback(void) 23 { 24 (void)HYPERVISOR_xen_version(0, NULL); 25 } 26 27 static noinstr void xen_safe_halt(void) 28 { 29 /* Blocking includes an implicit local_irq_enable(). */ 30 if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0) 31 BUG(); 32 } 33 34 static void xen_halt(void) 35 { 36 if (irqs_disabled()) 37 HYPERVISOR_vcpu_op(VCPUOP_down, 38 xen_vcpu_nr(smp_processor_id()), NULL); 39 else 40 xen_safe_halt(); 41 } 42 43 void __init xen_init_irq_ops(void) 44 { 45 /* Initial interrupt flag handling only called while interrupts off. */ 46 pv_ops.irq.save_fl = __PV_IS_CALLEE_SAVE(paravirt_ret0); 47 pv_ops.irq.irq_disable = __PV_IS_CALLEE_SAVE(paravirt_nop); 48 pv_ops.irq.irq_enable = __PV_IS_CALLEE_SAVE(BUG_func); 49 pv_ops.irq.safe_halt = xen_safe_halt; 50 pv_ops.irq.halt = xen_halt; 51 52 x86_init.irqs.intr_init = xen_init_IRQ; 53 } 54