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
17static 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	/* SPE present on this CPU? */
25	if (!cpuid_feature_extract_unsigned_field(read_sysreg(id_aa64dfr0_el1),
26						  ID_AA64DFR0_PMSVER_SHIFT))
27		return;
28
29	/* Yes; is it owned by EL3? */
30	reg = read_sysreg_s(SYS_PMBIDR_EL1);
31	if (reg & BIT(SYS_PMBIDR_EL1_P_SHIFT))
32		return;
33
34	/* No; is the host actually using the thing? */
35	reg = read_sysreg_s(SYS_PMBLIMITR_EL1);
36	if (!(reg & BIT(SYS_PMBLIMITR_EL1_E_SHIFT)))
37		return;
38
39	/* Yes; save the control register and disable data generation */
40	*pmscr_el1 = read_sysreg_s(SYS_PMSCR_EL1);
41	write_sysreg_s(0, SYS_PMSCR_EL1);
42	isb();
43
44	/* Now drain all buffered data to memory */
45	psb_csync();
46	dsb(nsh);
47}
48
49static void __debug_restore_spe(u64 pmscr_el1)
50{
51	if (!pmscr_el1)
52		return;
53
54	/* The host page table is installed, but not yet synchronised */
55	isb();
56
57	/* Re-enable data generation */
58	write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
59}
60
61void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
62{
63	/* Disable and flush SPE data generation */
64	__debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
65}
66
67void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
68{
69	__debug_switch_to_guest_common(vcpu);
70}
71
72void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
73{
74	__debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
75}
76
77void __debug_switch_to_host(struct kvm_vcpu *vcpu)
78{
79	__debug_switch_to_host_common(vcpu);
80}
81
82u32 __kvm_get_mdcr_el2(void)
83{
84	return read_sysreg(mdcr_el2);
85}
86