xref: /openbmc/linux/arch/x86/xen/suspend.c (revision 71c208dd)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/tick.h>
4 #include <linux/percpu-defs.h>
5 
6 #include <xen/xen.h>
7 #include <xen/interface/xen.h>
8 #include <xen/grant_table.h>
9 #include <xen/events.h>
10 
11 #include <asm/cpufeatures.h>
12 #include <asm/msr-index.h>
13 #include <asm/xen/hypercall.h>
14 #include <asm/xen/page.h>
15 #include <asm/fixmap.h>
16 
17 #include "xen-ops.h"
18 #include "mmu.h"
19 #include "pmu.h"
20 
21 static DEFINE_PER_CPU(u64, spec_ctrl);
22 
xen_arch_pre_suspend(void)23 void xen_arch_pre_suspend(void)
24 {
25 	xen_save_time_memory_area();
26 
27 	if (xen_pv_domain())
28 		xen_pv_pre_suspend();
29 }
30 
xen_arch_post_suspend(int cancelled)31 void xen_arch_post_suspend(int cancelled)
32 {
33 	if (xen_pv_domain())
34 		xen_pv_post_suspend(cancelled);
35 	else
36 		xen_hvm_post_suspend(cancelled);
37 
38 	xen_restore_time_memory_area();
39 }
40 
xen_vcpu_notify_restore(void * data)41 static void xen_vcpu_notify_restore(void *data)
42 {
43 	if (xen_pv_domain() && boot_cpu_has(X86_FEATURE_SPEC_CTRL))
44 		wrmsrl(MSR_IA32_SPEC_CTRL, this_cpu_read(spec_ctrl));
45 
46 	/* Boot processor notified via generic timekeeping_resume() */
47 	if (smp_processor_id() == 0)
48 		return;
49 
50 	tick_resume_local();
51 }
52 
xen_vcpu_notify_suspend(void * data)53 static void xen_vcpu_notify_suspend(void *data)
54 {
55 	u64 tmp;
56 
57 	tick_suspend_local();
58 
59 	if (xen_pv_domain() && boot_cpu_has(X86_FEATURE_SPEC_CTRL)) {
60 		rdmsrl(MSR_IA32_SPEC_CTRL, tmp);
61 		this_cpu_write(spec_ctrl, tmp);
62 		wrmsrl(MSR_IA32_SPEC_CTRL, 0);
63 	}
64 }
65 
xen_arch_resume(void)66 void xen_arch_resume(void)
67 {
68 	int cpu;
69 
70 	on_each_cpu(xen_vcpu_notify_restore, NULL, 1);
71 
72 	for_each_online_cpu(cpu)
73 		xen_pmu_init(cpu);
74 }
75 
xen_arch_suspend(void)76 void xen_arch_suspend(void)
77 {
78 	int cpu;
79 
80 	for_each_online_cpu(cpu)
81 		xen_pmu_finish(cpu);
82 
83 	on_each_cpu(xen_vcpu_notify_suspend, NULL, 1);
84 }
85