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
__debug_save_spe(u64 * pmscr_el1)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(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
__debug_restore_spe(u64 pmscr_el1)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
__debug_save_trace(u64 * trfcr_el1)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
__debug_restore_trace(u64 trfcr_el1)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
__debug_save_host_buffers_nvhe(struct kvm_vcpu * vcpu)84 void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
85 {
86 /* Disable and flush SPE data generation */
87 if (vcpu_get_flag(vcpu, 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_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
91 __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
92 }
93
__debug_switch_to_guest(struct kvm_vcpu * vcpu)94 void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
95 {
96 __debug_switch_to_guest_common(vcpu);
97 }
98
__debug_restore_host_buffers_nvhe(struct kvm_vcpu * vcpu)99 void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
100 {
101 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
102 __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
103 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
104 __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
105 }
106
__debug_switch_to_host(struct kvm_vcpu * vcpu)107 void __debug_switch_to_host(struct kvm_vcpu *vcpu)
108 {
109 __debug_switch_to_host_common(vcpu);
110 }
111
__kvm_get_mdcr_el2(void)112 u64 __kvm_get_mdcr_el2(void)
113 {
114 return read_sysreg(mdcr_el2);
115 }
116