// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#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>
#define read_debug(r,n) read_sysreg(r##n##_el1)
#define write_debug(v,r,n) write_sysreg(v, r##n##_el1)
#define save_debug(ptr,reg,nr) \
switch (nr) { \
case 15: ptr[15] = read_debug(reg, 15); \
/* Fall through */ \
case 14: ptr[14] = read_debug(reg, 14); \
/* Fall through */ \
case 13: ptr[13] = read_debug(reg, 13); \
/* Fall through */ \
case 12: ptr[12] = read_debug(reg, 12); \
/* Fall through */ \
case 11: ptr[11] = read_debug(reg, 11); \
/* Fall through */ \
case 10: ptr[10] = read_debug(reg, 10); \
/* Fall through */ \
case 9: ptr[9] = read_debug(reg, 9); \
/* Fall through */ \
case 8: ptr[8] = read_debug(reg, 8); \
/* Fall through */ \
case 7: ptr[7] = read_debug(reg, 7); \
/* Fall through */ \
case 6: ptr[6] = read_debug(reg, 6); \
/* Fall through */ \
case 5: ptr[5] = read_debug(reg, 5); \
/* Fall through */ \
case 4: ptr[4] = read_debug(reg, 4); \
/* Fall through */ \
case 3: ptr[3] = read_debug(reg, 3); \
/* Fall through */ \
case 2: ptr[2] = read_debug(reg, 2); \
/* Fall through */ \
case 1: ptr[1] = read_debug(reg, 1); \
/* Fall through */ \
default: ptr[0] = read_debug(reg, 0); \
}
#define restore_debug(ptr,reg,nr) \
switch (nr) { \
case 15: write_debug(ptr[15], reg, 15); \
/* Fall through */ \
case 14: write_debug(ptr[14], reg, 14); \
/* Fall through */ \
case 13: write_debug(ptr[13], reg, 13); \
/* Fall through */ \
case 12: write_debug(ptr[12], reg, 12); \
/* Fall through */ \
case 11: write_debug(ptr[11], reg, 11); \
/* Fall through */ \
case 10: write_debug(ptr[10], reg, 10); \
/* Fall through */ \
case 9: write_debug(ptr[9], reg, 9); \
/* Fall through */ \
case 8: write_debug(ptr[8], reg, 8); \
/* Fall through */ \
case 7: write_debug(ptr[7], reg, 7); \
/* Fall through */ \
case 6: write_debug(ptr[6], reg, 6); \
/* Fall through */ \
case 5: write_debug(ptr[5], reg, 5); \
/* Fall through */ \
case 4: write_debug(ptr[4], reg, 4); \
/* Fall through */ \
case 3: write_debug(ptr[3], reg, 3); \
/* Fall through */ \
case 2: write_debug(ptr[2], reg, 2); \
/* Fall through */ \
case 1: write_debug(ptr[1], reg, 1); \
/* Fall through */ \
default: write_debug(ptr[0], reg, 0); \
}
static void __hyp_text __debug_save_spe_nvhe(u64 *pmscr_el1)
{
u64 reg;
/* Clear pmscr in case of early return */
*pmscr_el1 = 0;
/* SPE present on this CPU? */
if (!cpuid_feature_extract_unsigned_field(read_sysreg(id_aa64dfr0_el1),
ID_AA64DFR0_PMSVER_SHIFT))
return;
/* Yes; is it owned by EL3? */
reg = read_sysreg_s(SYS_PMBIDR_EL1);
if (reg & BIT(SYS_PMBIDR_EL1_P_SHIFT))
return;
/* No; is the host actually using the thing? */
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 __hyp_text __debug_restore_spe_nvhe(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 __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
{
u64 aa64dfr0;
int brps, wrps;
aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
brps = (aa64dfr0 >> 12) & 0xf;
wrps = (aa64dfr0 >> 20) & 0xf;
save_debug(dbg->dbg_bcr, dbgbcr, brps);
save_debug(dbg->dbg_bvr, dbgbvr, brps);
save_debug(dbg->dbg_wcr, dbgwcr, wrps);
save_debug(dbg->dbg_wvr, dbgwvr, wrps);
ctxt->sys_regs[MDCCINT_EL1] = read_sysreg(mdccint_el1);
}
static void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
{
u64 aa64dfr0;
int brps, wrps;
aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
brps = (aa64dfr0 >> 12) & 0xf;
wrps = (aa64dfr0 >> 20) & 0xf;
restore_debug(dbg->dbg_bcr, dbgbcr, brps);
restore_debug(dbg->dbg_bvr, dbgbvr, brps);
restore_debug(dbg->dbg_wcr, dbgwcr, wrps);
restore_debug(dbg->dbg_wvr, dbgwvr, wrps);
write_sysreg(ctxt->sys_regs[MDCCINT_EL1], mdccint_el1);
}
void __hyp_text __debug_switch_to_guest(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;
/*
* Non-VHE: Disable and flush SPE data generation
* VHE: The vcpu can run, but it can't hide.
*/
if (!has_vhe())
__debug_save_spe_nvhe(&vcpu->arch.host_debug_state.pmscr_el1);
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
__debug_save_state(vcpu, host_dbg, host_ctxt);
__debug_restore_state(vcpu, guest_dbg, guest_ctxt);
}
void __hyp_text __debug_switch_to_host(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;
if (!has_vhe())
__debug_restore_spe_nvhe(vcpu->arch.host_debug_state.pmscr_el1);
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
__debug_save_state(vcpu, guest_dbg, guest_ctxt);
__debug_restore_state(vcpu, host_dbg, host_ctxt);
vcpu->arch.flags &= ~KVM_ARM64_DEBUG_DIRTY;
}
u32 __hyp_text __kvm_get_mdcr_el2(void)
{
return read_sysreg(mdcr_el2);
}