Merge remote-tracking branch 'spi/for-5.12' into spi-linus
[linux-2.6-microblaze.git] / arch / arm64 / kvm / hyp / nvhe / debug-sr.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  */
6
7 #include <hyp/debug-sr.h>
8
9 #include <linux/compiler.h>
10 #include <linux/kvm_host.h>
11
12 #include <asm/debug-monitors.h>
13 #include <asm/kvm_asm.h>
14 #include <asm/kvm_hyp.h>
15 #include <asm/kvm_mmu.h>
16
17 static void __debug_save_spe(u64 *pmscr_el1)
18 {
19         u64 reg;
20
21         /* Clear pmscr in case of early return */
22         *pmscr_el1 = 0;
23
24         /*
25          * At this point, we know that this CPU implements
26          * SPE and is available to the host.
27          * Check if the host is actually using it ?
28          */
29         reg = read_sysreg_s(SYS_PMBLIMITR_EL1);
30         if (!(reg & BIT(SYS_PMBLIMITR_EL1_E_SHIFT)))
31                 return;
32
33         /* Yes; save the control register and disable data generation */
34         *pmscr_el1 = read_sysreg_s(SYS_PMSCR_EL1);
35         write_sysreg_s(0, SYS_PMSCR_EL1);
36         isb();
37
38         /* Now drain all buffered data to memory */
39         psb_csync();
40         dsb(nsh);
41 }
42
43 static void __debug_restore_spe(u64 pmscr_el1)
44 {
45         if (!pmscr_el1)
46                 return;
47
48         /* The host page table is installed, but not yet synchronised */
49         isb();
50
51         /* Re-enable data generation */
52         write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
53 }
54
55 static void __debug_save_trace(u64 *trfcr_el1)
56 {
57         *trfcr_el1 = 0;
58
59         /* Check if the TRBE is enabled */
60         if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_ENABLE))
61                 return;
62         /*
63          * Prohibit trace generation while we are in guest.
64          * Since access to TRFCR_EL1 is trapped, the guest can't
65          * modify the filtering set by the host.
66          */
67         *trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1);
68         write_sysreg_s(0, SYS_TRFCR_EL1);
69         isb();
70         /* Drain the trace buffer to memory */
71         tsb_csync();
72         dsb(nsh);
73 }
74
75 static void __debug_restore_trace(u64 trfcr_el1)
76 {
77         if (!trfcr_el1)
78                 return;
79
80         /* Restore trace filter controls */
81         write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1);
82 }
83
84 void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
85 {
86         /* Disable and flush SPE data generation */
87         if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_SPE)
88                 __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
89         /* Disable and flush Self-Hosted Trace generation */
90         if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_TRBE)
91                 __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
92 }
93
94 void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
95 {
96         __debug_switch_to_guest_common(vcpu);
97 }
98
99 void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
100 {
101         if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_SPE)
102                 __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
103         if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_TRBE)
104                 __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
105 }
106
107 void __debug_switch_to_host(struct kvm_vcpu *vcpu)
108 {
109         __debug_switch_to_host_common(vcpu);
110 }
111
112 u32 __kvm_get_mdcr_el2(void)
113 {
114         return read_sysreg(mdcr_el2);
115 }