linux-zen-server/arch/arm64/kvm/hyp/nvhe/debug-sr.c

116 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#include <hyp/debug-sr.h>
#include <linux/compiler.h>
#include <linux/kvm_host.h>
#include <asm/debug-monitors.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_hyp.h>
#include <asm/kvm_mmu.h>
static void __debug_save_spe(u64 *pmscr_el1)
{
u64 reg;
/* Clear pmscr in case of early return */
*pmscr_el1 = 0;
/*
* At this point, we know that this CPU implements
* SPE and is available to the host.
* Check if the host is actually using it ?
*/
reg = read_sysreg_s(SYS_PMBLIMITR_EL1);
if (!(reg & BIT(PMBLIMITR_EL1_E_SHIFT)))
return;
/* Yes; save the control register and disable data generation */
*pmscr_el1 = read_sysreg_s(SYS_PMSCR_EL1);
write_sysreg_s(0, SYS_PMSCR_EL1);
isb();
/* Now drain all buffered data to memory */
psb_csync();
dsb(nsh);
}
static void __debug_restore_spe(u64 pmscr_el1)
{
if (!pmscr_el1)
return;
/* The host page table is installed, but not yet synchronised */
isb();
/* Re-enable data generation */
write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
}
static void __debug_save_trace(u64 *trfcr_el1)
{
*trfcr_el1 = 0;
/* Check if the TRBE is enabled */
if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_ENABLE))
return;
/*
* Prohibit trace generation while we are in guest.
* Since access to TRFCR_EL1 is trapped, the guest can't
* modify the filtering set by the host.
*/
*trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1);
write_sysreg_s(0, SYS_TRFCR_EL1);
isb();
/* Drain the trace buffer to memory */
tsb_csync();
dsb(nsh);
}
static void __debug_restore_trace(u64 trfcr_el1)
{
if (!trfcr_el1)
return;
/* Restore trace filter controls */
write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1);
}
void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
{
/* Disable and flush SPE data generation */
if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
__debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
/* Disable and flush Self-Hosted Trace generation */
if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
__debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
}
void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
{
__debug_switch_to_guest_common(vcpu);
}
void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
{
if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
__debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
__debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
}
void __debug_switch_to_host(struct kvm_vcpu *vcpu)
{
__debug_switch_to_host_common(vcpu);
}
u64 __kvm_get_mdcr_el2(void)
{
return read_sysreg(mdcr_el2);
}