1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2015 - ARM Ltd
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
7 #include <hyp/debug-sr.h>
9 #include <linux/compiler.h>
10 #include <linux/kvm_host.h>
12 #include <asm/debug-monitors.h>
13 #include <asm/kvm_asm.h>
14 #include <asm/kvm_hyp.h>
15 #include <asm/kvm_mmu.h>
17 static void __debug_save_spe(u64 *pmscr_el1)
21 /* Clear pmscr in case of early return */
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 ?
29 reg = read_sysreg_s(SYS_PMBLIMITR_EL1);
30 if (!(reg & BIT(PMBLIMITR_EL1_E_SHIFT)))
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);
38 /* Now drain all buffered data to memory */
42 static void __debug_restore_spe(u64 pmscr_el1)
47 /* The host page table is installed, but not yet synchronised */
50 /* Re-enable data generation */
51 write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
54 static void __debug_save_trace(u64 *trfcr_el1)
58 /* Check if the TRBE is enabled */
59 if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_EL1_E))
62 * Prohibit trace generation while we are in guest.
63 * Since access to TRFCR_EL1 is trapped, the guest can't
64 * modify the filtering set by the host.
66 *trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1);
67 write_sysreg_s(0, SYS_TRFCR_EL1);
69 /* Drain the trace buffer to memory */
73 static void __debug_restore_trace(u64 trfcr_el1)
78 /* Restore trace filter controls */
79 write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1);
82 void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
84 /* Disable and flush SPE data generation */
85 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
86 __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
87 /* Disable and flush Self-Hosted Trace generation */
88 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
89 __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
92 void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
94 __debug_switch_to_guest_common(vcpu);
97 void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
99 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
100 __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
101 if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
102 __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
105 void __debug_switch_to_host(struct kvm_vcpu *vcpu)
107 __debug_switch_to_host_common(vcpu);
110 u64 __kvm_get_mdcr_el2(void)
112 return read_sysreg(mdcr_el2);