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Diffstat (limited to 'kernel/arch/arm64/kvm/hyp.S')
| -rw-r--r-- | kernel/arch/arm64/kvm/hyp.S | 1298 |
1 files changed, 1298 insertions, 0 deletions
diff --git a/kernel/arch/arm64/kvm/hyp.S b/kernel/arch/arm64/kvm/hyp.S new file mode 100644 index 000000000..5befd010e --- /dev/null +++ b/kernel/arch/arm64/kvm/hyp.S @@ -0,0 +1,1298 @@ +/* + * Copyright (C) 2012,2013 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> + +#include <asm/asm-offsets.h> +#include <asm/assembler.h> +#include <asm/debug-monitors.h> +#include <asm/esr.h> +#include <asm/fpsimdmacros.h> +#include <asm/kvm.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_mmu.h> +#include <asm/memory.h> + +#define CPU_GP_REG_OFFSET(x) (CPU_GP_REGS + x) +#define CPU_XREG_OFFSET(x) CPU_GP_REG_OFFSET(CPU_USER_PT_REGS + 8*x) +#define CPU_SPSR_OFFSET(x) CPU_GP_REG_OFFSET(CPU_SPSR + 8*x) +#define CPU_SYSREG_OFFSET(x) (CPU_SYSREGS + 8*x) + + .text + .pushsection .hyp.text, "ax" + .align PAGE_SHIFT + +.macro save_common_regs + // x2: base address for cpu context + // x3: tmp register + + add x3, x2, #CPU_XREG_OFFSET(19) + stp x19, x20, [x3] + stp x21, x22, [x3, #16] + stp x23, x24, [x3, #32] + stp x25, x26, [x3, #48] + stp x27, x28, [x3, #64] + stp x29, lr, [x3, #80] + + mrs x19, sp_el0 + mrs x20, elr_el2 // EL1 PC + mrs x21, spsr_el2 // EL1 pstate + + stp x19, x20, [x3, #96] + str x21, [x3, #112] + + mrs x22, sp_el1 + mrs x23, elr_el1 + mrs x24, spsr_el1 + + str x22, [x2, #CPU_GP_REG_OFFSET(CPU_SP_EL1)] + str x23, [x2, #CPU_GP_REG_OFFSET(CPU_ELR_EL1)] + str x24, [x2, #CPU_SPSR_OFFSET(KVM_SPSR_EL1)] +.endm + +.macro restore_common_regs + // x2: base address for cpu context + // x3: tmp register + + ldr x22, [x2, #CPU_GP_REG_OFFSET(CPU_SP_EL1)] + ldr x23, [x2, #CPU_GP_REG_OFFSET(CPU_ELR_EL1)] + ldr x24, [x2, #CPU_SPSR_OFFSET(KVM_SPSR_EL1)] + + msr sp_el1, x22 + msr elr_el1, x23 + msr spsr_el1, x24 + + add x3, x2, #CPU_XREG_OFFSET(31) // SP_EL0 + ldp x19, x20, [x3] + ldr x21, [x3, #16] + + msr sp_el0, x19 + msr elr_el2, x20 // EL1 PC + msr spsr_el2, x21 // EL1 pstate + + add x3, x2, #CPU_XREG_OFFSET(19) + ldp x19, x20, [x3] + ldp x21, x22, [x3, #16] + ldp x23, x24, [x3, #32] + ldp x25, x26, [x3, #48] + ldp x27, x28, [x3, #64] + ldp x29, lr, [x3, #80] +.endm + +.macro save_host_regs + save_common_regs +.endm + +.macro restore_host_regs + restore_common_regs +.endm + +.macro save_fpsimd + // x2: cpu context address + // x3, x4: tmp regs + add x3, x2, #CPU_GP_REG_OFFSET(CPU_FP_REGS) + fpsimd_save x3, 4 +.endm + +.macro restore_fpsimd + // x2: cpu context address + // x3, x4: tmp regs + add x3, x2, #CPU_GP_REG_OFFSET(CPU_FP_REGS) + fpsimd_restore x3, 4 +.endm + +.macro save_guest_regs + // x0 is the vcpu address + // x1 is the return code, do not corrupt! + // x2 is the cpu context + // x3 is a tmp register + // Guest's x0-x3 are on the stack + + // Compute base to save registers + add x3, x2, #CPU_XREG_OFFSET(4) + stp x4, x5, [x3] + stp x6, x7, [x3, #16] + stp x8, x9, [x3, #32] + stp x10, x11, [x3, #48] + stp x12, x13, [x3, #64] + stp x14, x15, [x3, #80] + stp x16, x17, [x3, #96] + str x18, [x3, #112] + + pop x6, x7 // x2, x3 + pop x4, x5 // x0, x1 + + add x3, x2, #CPU_XREG_OFFSET(0) + stp x4, x5, [x3] + stp x6, x7, [x3, #16] + + save_common_regs +.endm + +.macro restore_guest_regs + // x0 is the vcpu address. + // x2 is the cpu context + // x3 is a tmp register + + // Prepare x0-x3 for later restore + add x3, x2, #CPU_XREG_OFFSET(0) + ldp x4, x5, [x3] + ldp x6, x7, [x3, #16] + push x4, x5 // Push x0-x3 on the stack + push x6, x7 + + // x4-x18 + ldp x4, x5, [x3, #32] + ldp x6, x7, [x3, #48] + ldp x8, x9, [x3, #64] + ldp x10, x11, [x3, #80] + ldp x12, x13, [x3, #96] + ldp x14, x15, [x3, #112] + ldp x16, x17, [x3, #128] + ldr x18, [x3, #144] + + // x19-x29, lr, sp*, elr*, spsr* + restore_common_regs + + // Last bits of the 64bit state + pop x2, x3 + pop x0, x1 + + // Do not touch any register after this! +.endm + +/* + * Macros to perform system register save/restore. + * + * Ordering here is absolutely critical, and must be kept consistent + * in {save,restore}_sysregs, {save,restore}_guest_32bit_state, + * and in kvm_asm.h. + * + * In other words, don't touch any of these unless you know what + * you are doing. + */ +.macro save_sysregs + // x2: base address for cpu context + // x3: tmp register + + add x3, x2, #CPU_SYSREG_OFFSET(MPIDR_EL1) + + mrs x4, vmpidr_el2 + mrs x5, csselr_el1 + mrs x6, sctlr_el1 + mrs x7, actlr_el1 + mrs x8, cpacr_el1 + mrs x9, ttbr0_el1 + mrs x10, ttbr1_el1 + mrs x11, tcr_el1 + mrs x12, esr_el1 + mrs x13, afsr0_el1 + mrs x14, afsr1_el1 + mrs x15, far_el1 + mrs x16, mair_el1 + mrs x17, vbar_el1 + mrs x18, contextidr_el1 + mrs x19, tpidr_el0 + mrs x20, tpidrro_el0 + mrs x21, tpidr_el1 + mrs x22, amair_el1 + mrs x23, cntkctl_el1 + mrs x24, par_el1 + mrs x25, mdscr_el1 + + stp x4, x5, [x3] + stp x6, x7, [x3, #16] + stp x8, x9, [x3, #32] + stp x10, x11, [x3, #48] + stp x12, x13, [x3, #64] + stp x14, x15, [x3, #80] + stp x16, x17, [x3, #96] + stp x18, x19, [x3, #112] + stp x20, x21, [x3, #128] + stp x22, x23, [x3, #144] + stp x24, x25, [x3, #160] +.endm + +.macro save_debug + // x2: base address for cpu context + // x3: tmp register + + mrs x26, id_aa64dfr0_el1 + ubfx x24, x26, #12, #4 // Extract BRPs + ubfx x25, x26, #20, #4 // Extract WRPs + mov w26, #15 + sub w24, w26, w24 // How many BPs to skip + sub w25, w26, w25 // How many WPs to skip + + add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + mrs x20, dbgbcr15_el1 + mrs x19, dbgbcr14_el1 + mrs x18, dbgbcr13_el1 + mrs x17, dbgbcr12_el1 + mrs x16, dbgbcr11_el1 + mrs x15, dbgbcr10_el1 + mrs x14, dbgbcr9_el1 + mrs x13, dbgbcr8_el1 + mrs x12, dbgbcr7_el1 + mrs x11, dbgbcr6_el1 + mrs x10, dbgbcr5_el1 + mrs x9, dbgbcr4_el1 + mrs x8, dbgbcr3_el1 + mrs x7, dbgbcr2_el1 + mrs x6, dbgbcr1_el1 + mrs x5, dbgbcr0_el1 + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 + +1: + str x20, [x3, #(15 * 8)] + str x19, [x3, #(14 * 8)] + str x18, [x3, #(13 * 8)] + str x17, [x3, #(12 * 8)] + str x16, [x3, #(11 * 8)] + str x15, [x3, #(10 * 8)] + str x14, [x3, #(9 * 8)] + str x13, [x3, #(8 * 8)] + str x12, [x3, #(7 * 8)] + str x11, [x3, #(6 * 8)] + str x10, [x3, #(5 * 8)] + str x9, [x3, #(4 * 8)] + str x8, [x3, #(3 * 8)] + str x7, [x3, #(2 * 8)] + str x6, [x3, #(1 * 8)] + str x5, [x3, #(0 * 8)] + + add x3, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + mrs x20, dbgbvr15_el1 + mrs x19, dbgbvr14_el1 + mrs x18, dbgbvr13_el1 + mrs x17, dbgbvr12_el1 + mrs x16, dbgbvr11_el1 + mrs x15, dbgbvr10_el1 + mrs x14, dbgbvr9_el1 + mrs x13, dbgbvr8_el1 + mrs x12, dbgbvr7_el1 + mrs x11, dbgbvr6_el1 + mrs x10, dbgbvr5_el1 + mrs x9, dbgbvr4_el1 + mrs x8, dbgbvr3_el1 + mrs x7, dbgbvr2_el1 + mrs x6, dbgbvr1_el1 + mrs x5, dbgbvr0_el1 + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 + +1: + str x20, [x3, #(15 * 8)] + str x19, [x3, #(14 * 8)] + str x18, [x3, #(13 * 8)] + str x17, [x3, #(12 * 8)] + str x16, [x3, #(11 * 8)] + str x15, [x3, #(10 * 8)] + str x14, [x3, #(9 * 8)] + str x13, [x3, #(8 * 8)] + str x12, [x3, #(7 * 8)] + str x11, [x3, #(6 * 8)] + str x10, [x3, #(5 * 8)] + str x9, [x3, #(4 * 8)] + str x8, [x3, #(3 * 8)] + str x7, [x3, #(2 * 8)] + str x6, [x3, #(1 * 8)] + str x5, [x3, #(0 * 8)] + + add x3, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + mrs x20, dbgwcr15_el1 + mrs x19, dbgwcr14_el1 + mrs x18, dbgwcr13_el1 + mrs x17, dbgwcr12_el1 + mrs x16, dbgwcr11_el1 + mrs x15, dbgwcr10_el1 + mrs x14, dbgwcr9_el1 + mrs x13, dbgwcr8_el1 + mrs x12, dbgwcr7_el1 + mrs x11, dbgwcr6_el1 + mrs x10, dbgwcr5_el1 + mrs x9, dbgwcr4_el1 + mrs x8, dbgwcr3_el1 + mrs x7, dbgwcr2_el1 + mrs x6, dbgwcr1_el1 + mrs x5, dbgwcr0_el1 + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 + +1: + str x20, [x3, #(15 * 8)] + str x19, [x3, #(14 * 8)] + str x18, [x3, #(13 * 8)] + str x17, [x3, #(12 * 8)] + str x16, [x3, #(11 * 8)] + str x15, [x3, #(10 * 8)] + str x14, [x3, #(9 * 8)] + str x13, [x3, #(8 * 8)] + str x12, [x3, #(7 * 8)] + str x11, [x3, #(6 * 8)] + str x10, [x3, #(5 * 8)] + str x9, [x3, #(4 * 8)] + str x8, [x3, #(3 * 8)] + str x7, [x3, #(2 * 8)] + str x6, [x3, #(1 * 8)] + str x5, [x3, #(0 * 8)] + + add x3, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + mrs x20, dbgwvr15_el1 + mrs x19, dbgwvr14_el1 + mrs x18, dbgwvr13_el1 + mrs x17, dbgwvr12_el1 + mrs x16, dbgwvr11_el1 + mrs x15, dbgwvr10_el1 + mrs x14, dbgwvr9_el1 + mrs x13, dbgwvr8_el1 + mrs x12, dbgwvr7_el1 + mrs x11, dbgwvr6_el1 + mrs x10, dbgwvr5_el1 + mrs x9, dbgwvr4_el1 + mrs x8, dbgwvr3_el1 + mrs x7, dbgwvr2_el1 + mrs x6, dbgwvr1_el1 + mrs x5, dbgwvr0_el1 + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 + +1: + str x20, [x3, #(15 * 8)] + str x19, [x3, #(14 * 8)] + str x18, [x3, #(13 * 8)] + str x17, [x3, #(12 * 8)] + str x16, [x3, #(11 * 8)] + str x15, [x3, #(10 * 8)] + str x14, [x3, #(9 * 8)] + str x13, [x3, #(8 * 8)] + str x12, [x3, #(7 * 8)] + str x11, [x3, #(6 * 8)] + str x10, [x3, #(5 * 8)] + str x9, [x3, #(4 * 8)] + str x8, [x3, #(3 * 8)] + str x7, [x3, #(2 * 8)] + str x6, [x3, #(1 * 8)] + str x5, [x3, #(0 * 8)] + + mrs x21, mdccint_el1 + str x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] +.endm + +.macro restore_sysregs + // x2: base address for cpu context + // x3: tmp register + + add x3, x2, #CPU_SYSREG_OFFSET(MPIDR_EL1) + + ldp x4, x5, [x3] + ldp x6, x7, [x3, #16] + ldp x8, x9, [x3, #32] + ldp x10, x11, [x3, #48] + ldp x12, x13, [x3, #64] + ldp x14, x15, [x3, #80] + ldp x16, x17, [x3, #96] + ldp x18, x19, [x3, #112] + ldp x20, x21, [x3, #128] + ldp x22, x23, [x3, #144] + ldp x24, x25, [x3, #160] + + msr vmpidr_el2, x4 + msr csselr_el1, x5 + msr sctlr_el1, x6 + msr actlr_el1, x7 + msr cpacr_el1, x8 + msr ttbr0_el1, x9 + msr ttbr1_el1, x10 + msr tcr_el1, x11 + msr esr_el1, x12 + msr afsr0_el1, x13 + msr afsr1_el1, x14 + msr far_el1, x15 + msr mair_el1, x16 + msr vbar_el1, x17 + msr contextidr_el1, x18 + msr tpidr_el0, x19 + msr tpidrro_el0, x20 + msr tpidr_el1, x21 + msr amair_el1, x22 + msr cntkctl_el1, x23 + msr par_el1, x24 + msr mdscr_el1, x25 +.endm + +.macro restore_debug + // x2: base address for cpu context + // x3: tmp register + + mrs x26, id_aa64dfr0_el1 + ubfx x24, x26, #12, #4 // Extract BRPs + ubfx x25, x26, #20, #4 // Extract WRPs + mov w26, #15 + sub w24, w26, w24 // How many BPs to skip + sub w25, w26, w25 // How many WPs to skip + + add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + ldr x20, [x3, #(15 * 8)] + ldr x19, [x3, #(14 * 8)] + ldr x18, [x3, #(13 * 8)] + ldr x17, [x3, #(12 * 8)] + ldr x16, [x3, #(11 * 8)] + ldr x15, [x3, #(10 * 8)] + ldr x14, [x3, #(9 * 8)] + ldr x13, [x3, #(8 * 8)] + ldr x12, [x3, #(7 * 8)] + ldr x11, [x3, #(6 * 8)] + ldr x10, [x3, #(5 * 8)] + ldr x9, [x3, #(4 * 8)] + ldr x8, [x3, #(3 * 8)] + ldr x7, [x3, #(2 * 8)] + ldr x6, [x3, #(1 * 8)] + ldr x5, [x3, #(0 * 8)] + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + msr dbgbcr15_el1, x20 + msr dbgbcr14_el1, x19 + msr dbgbcr13_el1, x18 + msr dbgbcr12_el1, x17 + msr dbgbcr11_el1, x16 + msr dbgbcr10_el1, x15 + msr dbgbcr9_el1, x14 + msr dbgbcr8_el1, x13 + msr dbgbcr7_el1, x12 + msr dbgbcr6_el1, x11 + msr dbgbcr5_el1, x10 + msr dbgbcr4_el1, x9 + msr dbgbcr3_el1, x8 + msr dbgbcr2_el1, x7 + msr dbgbcr1_el1, x6 + msr dbgbcr0_el1, x5 + + add x3, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + ldr x20, [x3, #(15 * 8)] + ldr x19, [x3, #(14 * 8)] + ldr x18, [x3, #(13 * 8)] + ldr x17, [x3, #(12 * 8)] + ldr x16, [x3, #(11 * 8)] + ldr x15, [x3, #(10 * 8)] + ldr x14, [x3, #(9 * 8)] + ldr x13, [x3, #(8 * 8)] + ldr x12, [x3, #(7 * 8)] + ldr x11, [x3, #(6 * 8)] + ldr x10, [x3, #(5 * 8)] + ldr x9, [x3, #(4 * 8)] + ldr x8, [x3, #(3 * 8)] + ldr x7, [x3, #(2 * 8)] + ldr x6, [x3, #(1 * 8)] + ldr x5, [x3, #(0 * 8)] + + adr x26, 1f + add x26, x26, x24, lsl #2 + br x26 +1: + msr dbgbvr15_el1, x20 + msr dbgbvr14_el1, x19 + msr dbgbvr13_el1, x18 + msr dbgbvr12_el1, x17 + msr dbgbvr11_el1, x16 + msr dbgbvr10_el1, x15 + msr dbgbvr9_el1, x14 + msr dbgbvr8_el1, x13 + msr dbgbvr7_el1, x12 + msr dbgbvr6_el1, x11 + msr dbgbvr5_el1, x10 + msr dbgbvr4_el1, x9 + msr dbgbvr3_el1, x8 + msr dbgbvr2_el1, x7 + msr dbgbvr1_el1, x6 + msr dbgbvr0_el1, x5 + + add x3, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + ldr x20, [x3, #(15 * 8)] + ldr x19, [x3, #(14 * 8)] + ldr x18, [x3, #(13 * 8)] + ldr x17, [x3, #(12 * 8)] + ldr x16, [x3, #(11 * 8)] + ldr x15, [x3, #(10 * 8)] + ldr x14, [x3, #(9 * 8)] + ldr x13, [x3, #(8 * 8)] + ldr x12, [x3, #(7 * 8)] + ldr x11, [x3, #(6 * 8)] + ldr x10, [x3, #(5 * 8)] + ldr x9, [x3, #(4 * 8)] + ldr x8, [x3, #(3 * 8)] + ldr x7, [x3, #(2 * 8)] + ldr x6, [x3, #(1 * 8)] + ldr x5, [x3, #(0 * 8)] + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + msr dbgwcr15_el1, x20 + msr dbgwcr14_el1, x19 + msr dbgwcr13_el1, x18 + msr dbgwcr12_el1, x17 + msr dbgwcr11_el1, x16 + msr dbgwcr10_el1, x15 + msr dbgwcr9_el1, x14 + msr dbgwcr8_el1, x13 + msr dbgwcr7_el1, x12 + msr dbgwcr6_el1, x11 + msr dbgwcr5_el1, x10 + msr dbgwcr4_el1, x9 + msr dbgwcr3_el1, x8 + msr dbgwcr2_el1, x7 + msr dbgwcr1_el1, x6 + msr dbgwcr0_el1, x5 + + add x3, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + ldr x20, [x3, #(15 * 8)] + ldr x19, [x3, #(14 * 8)] + ldr x18, [x3, #(13 * 8)] + ldr x17, [x3, #(12 * 8)] + ldr x16, [x3, #(11 * 8)] + ldr x15, [x3, #(10 * 8)] + ldr x14, [x3, #(9 * 8)] + ldr x13, [x3, #(8 * 8)] + ldr x12, [x3, #(7 * 8)] + ldr x11, [x3, #(6 * 8)] + ldr x10, [x3, #(5 * 8)] + ldr x9, [x3, #(4 * 8)] + ldr x8, [x3, #(3 * 8)] + ldr x7, [x3, #(2 * 8)] + ldr x6, [x3, #(1 * 8)] + ldr x5, [x3, #(0 * 8)] + + adr x26, 1f + add x26, x26, x25, lsl #2 + br x26 +1: + msr dbgwvr15_el1, x20 + msr dbgwvr14_el1, x19 + msr dbgwvr13_el1, x18 + msr dbgwvr12_el1, x17 + msr dbgwvr11_el1, x16 + msr dbgwvr10_el1, x15 + msr dbgwvr9_el1, x14 + msr dbgwvr8_el1, x13 + msr dbgwvr7_el1, x12 + msr dbgwvr6_el1, x11 + msr dbgwvr5_el1, x10 + msr dbgwvr4_el1, x9 + msr dbgwvr3_el1, x8 + msr dbgwvr2_el1, x7 + msr dbgwvr1_el1, x6 + msr dbgwvr0_el1, x5 + + ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] + msr mdccint_el1, x21 +.endm + +.macro skip_32bit_state tmp, target + // Skip 32bit state if not needed + mrs \tmp, hcr_el2 + tbnz \tmp, #HCR_RW_SHIFT, \target +.endm + +.macro skip_tee_state tmp, target + // Skip ThumbEE state if not needed + mrs \tmp, id_pfr0_el1 + tbz \tmp, #12, \target +.endm + +.macro skip_debug_state tmp, target + ldr \tmp, [x0, #VCPU_DEBUG_FLAGS] + tbz \tmp, #KVM_ARM64_DEBUG_DIRTY_SHIFT, \target +.endm + +.macro compute_debug_state target + // Compute debug state: If any of KDE, MDE or KVM_ARM64_DEBUG_DIRTY + // is set, we do a full save/restore cycle and disable trapping. + add x25, x0, #VCPU_CONTEXT + + // Check the state of MDSCR_EL1 + ldr x25, [x25, #CPU_SYSREG_OFFSET(MDSCR_EL1)] + and x26, x25, #DBG_MDSCR_KDE + and x25, x25, #DBG_MDSCR_MDE + adds xzr, x25, x26 + b.eq 9998f // Nothing to see there + + // If any interesting bits was set, we must set the flag + mov x26, #KVM_ARM64_DEBUG_DIRTY + str x26, [x0, #VCPU_DEBUG_FLAGS] + b 9999f // Don't skip restore + +9998: + // Otherwise load the flags from memory in case we recently + // trapped + skip_debug_state x25, \target +9999: +.endm + +.macro save_guest_32bit_state + skip_32bit_state x3, 1f + + add x3, x2, #CPU_SPSR_OFFSET(KVM_SPSR_ABT) + mrs x4, spsr_abt + mrs x5, spsr_und + mrs x6, spsr_irq + mrs x7, spsr_fiq + stp x4, x5, [x3] + stp x6, x7, [x3, #16] + + add x3, x2, #CPU_SYSREG_OFFSET(DACR32_EL2) + mrs x4, dacr32_el2 + mrs x5, ifsr32_el2 + mrs x6, fpexc32_el2 + stp x4, x5, [x3] + str x6, [x3, #16] + + skip_debug_state x8, 2f + mrs x7, dbgvcr32_el2 + str x7, [x3, #24] +2: + skip_tee_state x8, 1f + + add x3, x2, #CPU_SYSREG_OFFSET(TEECR32_EL1) + mrs x4, teecr32_el1 + mrs x5, teehbr32_el1 + stp x4, x5, [x3] +1: +.endm + +.macro restore_guest_32bit_state + skip_32bit_state x3, 1f + + add x3, x2, #CPU_SPSR_OFFSET(KVM_SPSR_ABT) + ldp x4, x5, [x3] + ldp x6, x7, [x3, #16] + msr spsr_abt, x4 + msr spsr_und, x5 + msr spsr_irq, x6 + msr spsr_fiq, x7 + + add x3, x2, #CPU_SYSREG_OFFSET(DACR32_EL2) + ldp x4, x5, [x3] + ldr x6, [x3, #16] + msr dacr32_el2, x4 + msr ifsr32_el2, x5 + msr fpexc32_el2, x6 + + skip_debug_state x8, 2f + ldr x7, [x3, #24] + msr dbgvcr32_el2, x7 +2: + skip_tee_state x8, 1f + + add x3, x2, #CPU_SYSREG_OFFSET(TEECR32_EL1) + ldp x4, x5, [x3] + msr teecr32_el1, x4 + msr teehbr32_el1, x5 +1: +.endm + +.macro activate_traps + ldr x2, [x0, #VCPU_HCR_EL2] + msr hcr_el2, x2 + mov x2, #CPTR_EL2_TTA + msr cptr_el2, x2 + + mov x2, #(1 << 15) // Trap CP15 Cr=15 + msr hstr_el2, x2 + + mrs x2, mdcr_el2 + and x2, x2, #MDCR_EL2_HPMN_MASK + orr x2, x2, #(MDCR_EL2_TPM | MDCR_EL2_TPMCR) + orr x2, x2, #(MDCR_EL2_TDRA | MDCR_EL2_TDOSA) + + // Check for KVM_ARM64_DEBUG_DIRTY, and set debug to trap + // if not dirty. + ldr x3, [x0, #VCPU_DEBUG_FLAGS] + tbnz x3, #KVM_ARM64_DEBUG_DIRTY_SHIFT, 1f + orr x2, x2, #MDCR_EL2_TDA +1: + msr mdcr_el2, x2 +.endm + +.macro deactivate_traps + mov x2, #HCR_RW + msr hcr_el2, x2 + msr cptr_el2, xzr + msr hstr_el2, xzr + + mrs x2, mdcr_el2 + and x2, x2, #MDCR_EL2_HPMN_MASK + msr mdcr_el2, x2 +.endm + +.macro activate_vm + ldr x1, [x0, #VCPU_KVM] + kern_hyp_va x1 + ldr x2, [x1, #KVM_VTTBR] + msr vttbr_el2, x2 +.endm + +.macro deactivate_vm + msr vttbr_el2, xzr +.endm + +/* + * Call into the vgic backend for state saving + */ +.macro save_vgic_state + adr x24, __vgic_sr_vectors + ldr x24, [x24, VGIC_SAVE_FN] + kern_hyp_va x24 + blr x24 + mrs x24, hcr_el2 + mov x25, #HCR_INT_OVERRIDE + neg x25, x25 + and x24, x24, x25 + msr hcr_el2, x24 +.endm + +/* + * Call into the vgic backend for state restoring + */ +.macro restore_vgic_state + mrs x24, hcr_el2 + ldr x25, [x0, #VCPU_IRQ_LINES] + orr x24, x24, #HCR_INT_OVERRIDE + orr x24, x24, x25 + msr hcr_el2, x24 + adr x24, __vgic_sr_vectors + ldr x24, [x24, #VGIC_RESTORE_FN] + kern_hyp_va x24 + blr x24 +.endm + +.macro save_timer_state + // x0: vcpu pointer + ldr x2, [x0, #VCPU_KVM] + kern_hyp_va x2 + ldr w3, [x2, #KVM_TIMER_ENABLED] + cbz w3, 1f + + mrs x3, cntv_ctl_el0 + and x3, x3, #3 + str w3, [x0, #VCPU_TIMER_CNTV_CTL] + bic x3, x3, #1 // Clear Enable + msr cntv_ctl_el0, x3 + + isb + + mrs x3, cntv_cval_el0 + str x3, [x0, #VCPU_TIMER_CNTV_CVAL] + +1: + // Allow physical timer/counter access for the host + mrs x2, cnthctl_el2 + orr x2, x2, #3 + msr cnthctl_el2, x2 + + // Clear cntvoff for the host + msr cntvoff_el2, xzr +.endm + +.macro restore_timer_state + // x0: vcpu pointer + // Disallow physical timer access for the guest + // Physical counter access is allowed + mrs x2, cnthctl_el2 + orr x2, x2, #1 + bic x2, x2, #2 + msr cnthctl_el2, x2 + + ldr x2, [x0, #VCPU_KVM] + kern_hyp_va x2 + ldr w3, [x2, #KVM_TIMER_ENABLED] + cbz w3, 1f + + ldr x3, [x2, #KVM_TIMER_CNTVOFF] + msr cntvoff_el2, x3 + ldr x2, [x0, #VCPU_TIMER_CNTV_CVAL] + msr cntv_cval_el0, x2 + isb + + ldr w2, [x0, #VCPU_TIMER_CNTV_CTL] + and x2, x2, #3 + msr cntv_ctl_el0, x2 +1: +.endm + +__save_sysregs: + save_sysregs + ret + +__restore_sysregs: + restore_sysregs + ret + +__save_debug: + save_debug + ret + +__restore_debug: + restore_debug + ret + +__save_fpsimd: + save_fpsimd + ret + +__restore_fpsimd: + restore_fpsimd + ret + +/* + * u64 __kvm_vcpu_run(struct kvm_vcpu *vcpu); + * + * This is the world switch. The first half of the function + * deals with entering the guest, and anything from __kvm_vcpu_return + * to the end of the function deals with reentering the host. + * On the enter path, only x0 (vcpu pointer) must be preserved until + * the last moment. On the exit path, x0 (vcpu pointer) and x1 (exception + * code) must both be preserved until the epilogue. + * In both cases, x2 points to the CPU context we're saving/restoring from/to. + */ +ENTRY(__kvm_vcpu_run) + kern_hyp_va x0 + msr tpidr_el2, x0 // Save the vcpu register + + // Host context + ldr x2, [x0, #VCPU_HOST_CONTEXT] + kern_hyp_va x2 + + save_host_regs + bl __save_fpsimd + bl __save_sysregs + + compute_debug_state 1f + bl __save_debug +1: + activate_traps + activate_vm + + restore_vgic_state + restore_timer_state + + // Guest context + add x2, x0, #VCPU_CONTEXT + + bl __restore_sysregs + bl __restore_fpsimd + + skip_debug_state x3, 1f + bl __restore_debug +1: + restore_guest_32bit_state + restore_guest_regs + + // That's it, no more messing around. + eret + +__kvm_vcpu_return: + // Assume x0 is the vcpu pointer, x1 the return code + // Guest's x0-x3 are on the stack + + // Guest context + add x2, x0, #VCPU_CONTEXT + + save_guest_regs + bl __save_fpsimd + bl __save_sysregs + + skip_debug_state x3, 1f + bl __save_debug +1: + save_guest_32bit_state + + save_timer_state + save_vgic_state + + deactivate_traps + deactivate_vm + + // Host context + ldr x2, [x0, #VCPU_HOST_CONTEXT] + kern_hyp_va x2 + + bl __restore_sysregs + bl __restore_fpsimd + + skip_debug_state x3, 1f + // Clear the dirty flag for the next run, as all the state has + // already been saved. Note that we nuke the whole 64bit word. + // If we ever add more flags, we'll have to be more careful... + str xzr, [x0, #VCPU_DEBUG_FLAGS] + bl __restore_debug +1: + restore_host_regs + + mov x0, x1 + ret +END(__kvm_vcpu_run) + +// void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa); +ENTRY(__kvm_tlb_flush_vmid_ipa) + dsb ishst + + kern_hyp_va x0 + ldr x2, [x0, #KVM_VTTBR] + msr vttbr_el2, x2 + isb + + /* + * We could do so much better if we had the VA as well. + * Instead, we invalidate Stage-2 for this IPA, and the + * whole of Stage-1. Weep... + */ + lsr x1, x1, #12 + tlbi ipas2e1is, x1 + /* + * We have to ensure completion of the invalidation at Stage-2, + * since a table walk on another CPU could refill a TLB with a + * complete (S1 + S2) walk based on the old Stage-2 mapping if + * the Stage-1 invalidation happened first. + */ + dsb ish + tlbi vmalle1is + dsb ish + isb + + msr vttbr_el2, xzr + ret +ENDPROC(__kvm_tlb_flush_vmid_ipa) + +/** + * void __kvm_tlb_flush_vmid(struct kvm *kvm) - Flush per-VMID TLBs + * @struct kvm *kvm - pointer to kvm structure + * + * Invalidates all Stage 1 and 2 TLB entries for current VMID. + */ +ENTRY(__kvm_tlb_flush_vmid) + dsb ishst + + kern_hyp_va x0 + ldr x2, [x0, #KVM_VTTBR] + msr vttbr_el2, x2 + isb + + tlbi vmalls12e1is + dsb ish + isb + + msr vttbr_el2, xzr + ret +ENDPROC(__kvm_tlb_flush_vmid) + +ENTRY(__kvm_flush_vm_context) + dsb ishst + tlbi alle1is + ic ialluis + dsb ish + ret +ENDPROC(__kvm_flush_vm_context) + + // struct vgic_sr_vectors __vgi_sr_vectors; + .align 3 +ENTRY(__vgic_sr_vectors) + .skip VGIC_SR_VECTOR_SZ +ENDPROC(__vgic_sr_vectors) + +__kvm_hyp_panic: + // Guess the context by looking at VTTBR: + // If zero, then we're already a host. + // Otherwise restore a minimal host context before panicing. + mrs x0, vttbr_el2 + cbz x0, 1f + + mrs x0, tpidr_el2 + + deactivate_traps + deactivate_vm + + ldr x2, [x0, #VCPU_HOST_CONTEXT] + kern_hyp_va x2 + + bl __restore_sysregs + +1: adr x0, __hyp_panic_str + adr x1, 2f + ldp x2, x3, [x1] + sub x0, x0, x2 + add x0, x0, x3 + mrs x1, spsr_el2 + mrs x2, elr_el2 + mrs x3, esr_el2 + mrs x4, far_el2 + mrs x5, hpfar_el2 + mrs x6, par_el1 + mrs x7, tpidr_el2 + + mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ + PSR_MODE_EL1h) + msr spsr_el2, lr + ldr lr, =panic + msr elr_el2, lr + eret + + .align 3 +2: .quad HYP_PAGE_OFFSET + .quad PAGE_OFFSET +ENDPROC(__kvm_hyp_panic) + +__hyp_panic_str: + .ascii "HYP panic:\nPS:%08x PC:%p ESR:%p\nFAR:%p HPFAR:%p PAR:%p\nVCPU:%p\n\0" + + .align 2 + +/* + * u64 kvm_call_hyp(void *hypfn, ...); + * + * This is not really a variadic function in the classic C-way and care must + * be taken when calling this to ensure parameters are passed in registers + * only, since the stack will change between the caller and the callee. + * + * Call the function with the first argument containing a pointer to the + * function you wish to call in Hyp mode, and subsequent arguments will be + * passed as x0, x1, and x2 (a maximum of 3 arguments in addition to the + * function pointer can be passed). The function being called must be mapped + * in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are + * passed in r0 and r1. + * + * A function pointer with a value of 0 has a special meaning, and is + * used to implement __hyp_get_vectors in the same way as in + * arch/arm64/kernel/hyp_stub.S. + */ +ENTRY(kvm_call_hyp) + hvc #0 + ret +ENDPROC(kvm_call_hyp) + +.macro invalid_vector label, target + .align 2 +\label: + b \target +ENDPROC(\label) +.endm + + /* None of these should ever happen */ + invalid_vector el2t_sync_invalid, __kvm_hyp_panic + invalid_vector el2t_irq_invalid, __kvm_hyp_panic + invalid_vector el2t_fiq_invalid, __kvm_hyp_panic + invalid_vector el2t_error_invalid, __kvm_hyp_panic + invalid_vector el2h_sync_invalid, __kvm_hyp_panic + invalid_vector el2h_irq_invalid, __kvm_hyp_panic + invalid_vector el2h_fiq_invalid, __kvm_hyp_panic + invalid_vector el2h_error_invalid, __kvm_hyp_panic + invalid_vector el1_sync_invalid, __kvm_hyp_panic + invalid_vector el1_irq_invalid, __kvm_hyp_panic + invalid_vector el1_fiq_invalid, __kvm_hyp_panic + invalid_vector el1_error_invalid, __kvm_hyp_panic + +el1_sync: // Guest trapped into EL2 + push x0, x1 + push x2, x3 + + mrs x1, esr_el2 + lsr x2, x1, #ESR_ELx_EC_SHIFT + + cmp x2, #ESR_ELx_EC_HVC64 + b.ne el1_trap + + mrs x3, vttbr_el2 // If vttbr is valid, the 64bit guest + cbnz x3, el1_trap // called HVC + + /* Here, we're pretty sure the host called HVC. */ + pop x2, x3 + pop x0, x1 + + /* Check for __hyp_get_vectors */ + cbnz x0, 1f + mrs x0, vbar_el2 + b 2f + +1: push lr, xzr + + /* + * Compute the function address in EL2, and shuffle the parameters. + */ + kern_hyp_va x0 + mov lr, x0 + mov x0, x1 + mov x1, x2 + mov x2, x3 + blr lr + + pop lr, xzr +2: eret + +el1_trap: + /* + * x1: ESR + * x2: ESR_EC + */ + cmp x2, #ESR_ELx_EC_DABT_LOW + mov x0, #ESR_ELx_EC_IABT_LOW + ccmp x2, x0, #4, ne + b.ne 1f // Not an abort we care about + + /* This is an abort. Check for permission fault */ + and x2, x1, #ESR_ELx_FSC_TYPE + cmp x2, #FSC_PERM + b.ne 1f // Not a permission fault + + /* + * Check for Stage-1 page table walk, which is guaranteed + * to give a valid HPFAR_EL2. + */ + tbnz x1, #7, 1f // S1PTW is set + + /* Preserve PAR_EL1 */ + mrs x3, par_el1 + push x3, xzr + + /* + * Permission fault, HPFAR_EL2 is invalid. + * Resolve the IPA the hard way using the guest VA. + * Stage-1 translation already validated the memory access rights. + * As such, we can use the EL1 translation regime, and don't have + * to distinguish between EL0 and EL1 access. + */ + mrs x2, far_el2 + at s1e1r, x2 + isb + + /* Read result */ + mrs x3, par_el1 + pop x0, xzr // Restore PAR_EL1 from the stack + msr par_el1, x0 + tbnz x3, #0, 3f // Bail out if we failed the translation + ubfx x3, x3, #12, #36 // Extract IPA + lsl x3, x3, #4 // and present it like HPFAR + b 2f + +1: mrs x3, hpfar_el2 + mrs x2, far_el2 + +2: mrs x0, tpidr_el2 + str w1, [x0, #VCPU_ESR_EL2] + str x2, [x0, #VCPU_FAR_EL2] + str x3, [x0, #VCPU_HPFAR_EL2] + + mov x1, #ARM_EXCEPTION_TRAP + b __kvm_vcpu_return + + /* + * Translation failed. Just return to the guest and + * let it fault again. Another CPU is probably playing + * behind our back. + */ +3: pop x2, x3 + pop x0, x1 + + eret + +el1_irq: + push x0, x1 + push x2, x3 + mrs x0, tpidr_el2 + mov x1, #ARM_EXCEPTION_IRQ + b __kvm_vcpu_return + + .ltorg + + .align 11 + +ENTRY(__kvm_hyp_vector) + ventry el2t_sync_invalid // Synchronous EL2t + ventry el2t_irq_invalid // IRQ EL2t + ventry el2t_fiq_invalid // FIQ EL2t + ventry el2t_error_invalid // Error EL2t + + ventry el2h_sync_invalid // Synchronous EL2h + ventry el2h_irq_invalid // IRQ EL2h + ventry el2h_fiq_invalid // FIQ EL2h + ventry el2h_error_invalid // Error EL2h + + ventry el1_sync // Synchronous 64-bit EL1 + ventry el1_irq // IRQ 64-bit EL1 + ventry el1_fiq_invalid // FIQ 64-bit EL1 + ventry el1_error_invalid // Error 64-bit EL1 + + ventry el1_sync // Synchronous 32-bit EL1 + ventry el1_irq // IRQ 32-bit EL1 + ventry el1_fiq_invalid // FIQ 32-bit EL1 + ventry el1_error_invalid // Error 32-bit EL1 +ENDPROC(__kvm_hyp_vector) + + .popsection |