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 */
xen_force_evtchn_callback(void)22 noinstr void xen_force_evtchn_callback(void)
23 {
24 (void)HYPERVISOR_xen_version(0, NULL);
25 }
26
xen_safe_halt(void)27 static 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
xen_halt(void)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 static const typeof(pv_ops) xen_irq_ops __initconst = {
44 .irq = {
45 /* Initial interrupt flag handling only called while interrupts off. */
46 .save_fl = __PV_IS_CALLEE_SAVE(paravirt_ret0),
47 .irq_disable = __PV_IS_CALLEE_SAVE(paravirt_nop),
48 .irq_enable = __PV_IS_CALLEE_SAVE(paravirt_BUG),
49
50 .safe_halt = xen_safe_halt,
51 .halt = xen_halt,
52 },
53 };
54
xen_init_irq_ops(void)55 void __init xen_init_irq_ops(void)
56 {
57 pv_ops.irq = xen_irq_ops.irq;
58 x86_init.irqs.intr_init = xen_init_IRQ;
59 }
60