diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/debug-sr.c')
-rw-r--r-- | arch/arm64/kvm/hyp/nvhe/debug-sr.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c new file mode 100644 index 000000000..e17455773 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c @@ -0,0 +1,115 @@ +// 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(SYS_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); +} |