korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-04 17:44:14 +08:00
Code Issues Packages Projects Releases Wiki Activity
5de52d4a23
linux/arch/riscv/kvm/vcpu_switch.S
Atish Patra 5de52d4a23 RISC-V: KVM: FP lazy save/restore 
This patch adds floating point (F and D extension) context save/restore
for guest VCPUs. The FP context is saved and restored lazily only when
kernel enter/exits the in-kernel run loop and not during the KVM world
switch. This way FP save/restore has minimal impact on KVM performance.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-10-04 16:08:23 +05:30

401 lines
11 KiB
ArmAsm
Raw Blame History

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <linux/linkage.h>
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/csr.h>
.text
.altmacro
.option norelax
ENTRY(__kvm_riscv_switch_to)
/* Save Host GPRs (except A0 and T0-T6) */
REG_S ra, (KVM_ARCH_HOST_RA)(a0)
REG_S sp, (KVM_ARCH_HOST_SP)(a0)
REG_S gp, (KVM_ARCH_HOST_GP)(a0)
REG_S tp, (KVM_ARCH_HOST_TP)(a0)
REG_S s0, (KVM_ARCH_HOST_S0)(a0)
REG_S s1, (KVM_ARCH_HOST_S1)(a0)
REG_S a1, (KVM_ARCH_HOST_A1)(a0)
REG_S a2, (KVM_ARCH_HOST_A2)(a0)
REG_S a3, (KVM_ARCH_HOST_A3)(a0)
REG_S a4, (KVM_ARCH_HOST_A4)(a0)
REG_S a5, (KVM_ARCH_HOST_A5)(a0)
REG_S a6, (KVM_ARCH_HOST_A6)(a0)
REG_S a7, (KVM_ARCH_HOST_A7)(a0)
REG_S s2, (KVM_ARCH_HOST_S2)(a0)
REG_S s3, (KVM_ARCH_HOST_S3)(a0)
REG_S s4, (KVM_ARCH_HOST_S4)(a0)
REG_S s5, (KVM_ARCH_HOST_S5)(a0)
REG_S s6, (KVM_ARCH_HOST_S6)(a0)
REG_S s7, (KVM_ARCH_HOST_S7)(a0)
REG_S s8, (KVM_ARCH_HOST_S8)(a0)
REG_S s9, (KVM_ARCH_HOST_S9)(a0)
REG_S s10, (KVM_ARCH_HOST_S10)(a0)
REG_S s11, (KVM_ARCH_HOST_S11)(a0)
/* Save Host and Restore Guest SSTATUS */
REG_L t0, (KVM_ARCH_GUEST_SSTATUS)(a0)
csrrw t0, CSR_SSTATUS, t0
REG_S t0, (KVM_ARCH_HOST_SSTATUS)(a0)
/* Save Host and Restore Guest HSTATUS */
REG_L t1, (KVM_ARCH_GUEST_HSTATUS)(a0)
csrrw t1, CSR_HSTATUS, t1
REG_S t1, (KVM_ARCH_HOST_HSTATUS)(a0)
/* Save Host and Restore Guest SCOUNTEREN */
REG_L t2, (KVM_ARCH_GUEST_SCOUNTEREN)(a0)
csrrw t2, CSR_SCOUNTEREN, t2
REG_S t2, (KVM_ARCH_HOST_SCOUNTEREN)(a0)
/* Save Host SSCRATCH and change it to struct kvm_vcpu_arch pointer */
csrrw t3, CSR_SSCRATCH, a0
REG_S t3, (KVM_ARCH_HOST_SSCRATCH)(a0)
/* Save Host STVEC and change it to return path */
la t4, __kvm_switch_return
csrrw t4, CSR_STVEC, t4
REG_S t4, (KVM_ARCH_HOST_STVEC)(a0)
/* Restore Guest SEPC */
REG_L t0, (KVM_ARCH_GUEST_SEPC)(a0)
csrw CSR_SEPC, t0
/* Restore Guest GPRs (except A0) */
REG_L ra, (KVM_ARCH_GUEST_RA)(a0)
REG_L sp, (KVM_ARCH_GUEST_SP)(a0)
REG_L gp, (KVM_ARCH_GUEST_GP)(a0)
REG_L tp, (KVM_ARCH_GUEST_TP)(a0)
REG_L t0, (KVM_ARCH_GUEST_T0)(a0)
REG_L t1, (KVM_ARCH_GUEST_T1)(a0)
REG_L t2, (KVM_ARCH_GUEST_T2)(a0)
REG_L s0, (KVM_ARCH_GUEST_S0)(a0)
REG_L s1, (KVM_ARCH_GUEST_S1)(a0)
REG_L a1, (KVM_ARCH_GUEST_A1)(a0)
REG_L a2, (KVM_ARCH_GUEST_A2)(a0)
REG_L a3, (KVM_ARCH_GUEST_A3)(a0)
REG_L a4, (KVM_ARCH_GUEST_A4)(a0)
REG_L a5, (KVM_ARCH_GUEST_A5)(a0)
REG_L a6, (KVM_ARCH_GUEST_A6)(a0)
REG_L a7, (KVM_ARCH_GUEST_A7)(a0)
REG_L s2, (KVM_ARCH_GUEST_S2)(a0)
REG_L s3, (KVM_ARCH_GUEST_S3)(a0)
REG_L s4, (KVM_ARCH_GUEST_S4)(a0)
REG_L s5, (KVM_ARCH_GUEST_S5)(a0)
REG_L s6, (KVM_ARCH_GUEST_S6)(a0)
REG_L s7, (KVM_ARCH_GUEST_S7)(a0)
REG_L s8, (KVM_ARCH_GUEST_S8)(a0)
REG_L s9, (KVM_ARCH_GUEST_S9)(a0)
REG_L s10, (KVM_ARCH_GUEST_S10)(a0)
REG_L s11, (KVM_ARCH_GUEST_S11)(a0)
REG_L t3, (KVM_ARCH_GUEST_T3)(a0)
REG_L t4, (KVM_ARCH_GUEST_T4)(a0)
REG_L t5, (KVM_ARCH_GUEST_T5)(a0)
REG_L t6, (KVM_ARCH_GUEST_T6)(a0)
/* Restore Guest A0 */
REG_L a0, (KVM_ARCH_GUEST_A0)(a0)
/* Resume Guest */
sret
/* Back to Host */
.align 2
__kvm_switch_return:
/* Swap Guest A0 with SSCRATCH */
csrrw a0, CSR_SSCRATCH, a0
/* Save Guest GPRs (except A0) */
REG_S ra, (KVM_ARCH_GUEST_RA)(a0)
REG_S sp, (KVM_ARCH_GUEST_SP)(a0)
REG_S gp, (KVM_ARCH_GUEST_GP)(a0)
REG_S tp, (KVM_ARCH_GUEST_TP)(a0)
REG_S t0, (KVM_ARCH_GUEST_T0)(a0)
REG_S t1, (KVM_ARCH_GUEST_T1)(a0)
REG_S t2, (KVM_ARCH_GUEST_T2)(a0)
REG_S s0, (KVM_ARCH_GUEST_S0)(a0)
REG_S s1, (KVM_ARCH_GUEST_S1)(a0)
REG_S a1, (KVM_ARCH_GUEST_A1)(a0)
REG_S a2, (KVM_ARCH_GUEST_A2)(a0)
REG_S a3, (KVM_ARCH_GUEST_A3)(a0)
REG_S a4, (KVM_ARCH_GUEST_A4)(a0)
REG_S a5, (KVM_ARCH_GUEST_A5)(a0)
REG_S a6, (KVM_ARCH_GUEST_A6)(a0)
REG_S a7, (KVM_ARCH_GUEST_A7)(a0)
REG_S s2, (KVM_ARCH_GUEST_S2)(a0)
REG_S s3, (KVM_ARCH_GUEST_S3)(a0)
REG_S s4, (KVM_ARCH_GUEST_S4)(a0)
REG_S s5, (KVM_ARCH_GUEST_S5)(a0)
REG_S s6, (KVM_ARCH_GUEST_S6)(a0)
REG_S s7, (KVM_ARCH_GUEST_S7)(a0)
REG_S s8, (KVM_ARCH_GUEST_S8)(a0)
REG_S s9, (KVM_ARCH_GUEST_S9)(a0)
REG_S s10, (KVM_ARCH_GUEST_S10)(a0)
REG_S s11, (KVM_ARCH_GUEST_S11)(a0)
REG_S t3, (KVM_ARCH_GUEST_T3)(a0)
REG_S t4, (KVM_ARCH_GUEST_T4)(a0)
REG_S t5, (KVM_ARCH_GUEST_T5)(a0)
REG_S t6, (KVM_ARCH_GUEST_T6)(a0)
/* Save Guest SEPC */
csrr t0, CSR_SEPC
REG_S t0, (KVM_ARCH_GUEST_SEPC)(a0)
/* Restore Host STVEC */
REG_L t1, (KVM_ARCH_HOST_STVEC)(a0)
csrw CSR_STVEC, t1
/* Save Guest A0 and Restore Host SSCRATCH */
REG_L t2, (KVM_ARCH_HOST_SSCRATCH)(a0)
csrrw t2, CSR_SSCRATCH, t2
REG_S t2, (KVM_ARCH_GUEST_A0)(a0)
/* Save Guest and Restore Host SCOUNTEREN */
REG_L t3, (KVM_ARCH_HOST_SCOUNTEREN)(a0)
csrrw t3, CSR_SCOUNTEREN, t3
REG_S t3, (KVM_ARCH_GUEST_SCOUNTEREN)(a0)
/* Save Guest and Restore Host HSTATUS */
REG_L t4, (KVM_ARCH_HOST_HSTATUS)(a0)
csrrw t4, CSR_HSTATUS, t4
REG_S t4, (KVM_ARCH_GUEST_HSTATUS)(a0)
/* Save Guest and Restore Host SSTATUS */
REG_L t5, (KVM_ARCH_HOST_SSTATUS)(a0)
csrrw t5, CSR_SSTATUS, t5
REG_S t5, (KVM_ARCH_GUEST_SSTATUS)(a0)
/* Restore Host GPRs (except A0 and T0-T6) */
REG_L ra, (KVM_ARCH_HOST_RA)(a0)
REG_L sp, (KVM_ARCH_HOST_SP)(a0)
REG_L gp, (KVM_ARCH_HOST_GP)(a0)
REG_L tp, (KVM_ARCH_HOST_TP)(a0)
REG_L s0, (KVM_ARCH_HOST_S0)(a0)
REG_L s1, (KVM_ARCH_HOST_S1)(a0)
REG_L a1, (KVM_ARCH_HOST_A1)(a0)
REG_L a2, (KVM_ARCH_HOST_A2)(a0)
REG_L a3, (KVM_ARCH_HOST_A3)(a0)
REG_L a4, (KVM_ARCH_HOST_A4)(a0)
REG_L a5, (KVM_ARCH_HOST_A5)(a0)
REG_L a6, (KVM_ARCH_HOST_A6)(a0)
REG_L a7, (KVM_ARCH_HOST_A7)(a0)
REG_L s2, (KVM_ARCH_HOST_S2)(a0)
REG_L s3, (KVM_ARCH_HOST_S3)(a0)
REG_L s4, (KVM_ARCH_HOST_S4)(a0)
REG_L s5, (KVM_ARCH_HOST_S5)(a0)
REG_L s6, (KVM_ARCH_HOST_S6)(a0)
REG_L s7, (KVM_ARCH_HOST_S7)(a0)
REG_L s8, (KVM_ARCH_HOST_S8)(a0)
REG_L s9, (KVM_ARCH_HOST_S9)(a0)
REG_L s10, (KVM_ARCH_HOST_S10)(a0)
REG_L s11, (KVM_ARCH_HOST_S11)(a0)
/* Return to C code */
ret
ENDPROC(__kvm_riscv_switch_to)
ENTRY(__kvm_riscv_unpriv_trap)
/*
* We assume that faulting unpriv load/store instruction is
* 4-byte long and blindly increment SEPC by 4.
*
* The trap details will be saved at address pointed by 'A0'
* register and we use 'A1' register as temporary.
*/
csrr a1, CSR_SEPC
REG_S a1, (KVM_ARCH_TRAP_SEPC)(a0)
addi a1, a1, 4
csrw CSR_SEPC, a1
csrr a1, CSR_SCAUSE
REG_S a1, (KVM_ARCH_TRAP_SCAUSE)(a0)
csrr a1, CSR_STVAL
REG_S a1, (KVM_ARCH_TRAP_STVAL)(a0)
csrr a1, CSR_HTVAL
REG_S a1, (KVM_ARCH_TRAP_HTVAL)(a0)
csrr a1, CSR_HTINST
REG_S a1, (KVM_ARCH_TRAP_HTINST)(a0)
sret
ENDPROC(__kvm_riscv_unpriv_trap)
#ifdef CONFIG_FPU
.align 3
.global __kvm_riscv_fp_f_save
__kvm_riscv_fp_f_save:
csrr t2, CSR_SSTATUS
li t1, SR_FS
csrs CSR_SSTATUS, t1
frcsr t0
fsw f0, KVM_ARCH_FP_F_F0(a0)
fsw f1, KVM_ARCH_FP_F_F1(a0)
fsw f2, KVM_ARCH_FP_F_F2(a0)
fsw f3, KVM_ARCH_FP_F_F3(a0)
fsw f4, KVM_ARCH_FP_F_F4(a0)
fsw f5, KVM_ARCH_FP_F_F5(a0)
fsw f6, KVM_ARCH_FP_F_F6(a0)
fsw f7, KVM_ARCH_FP_F_F7(a0)
fsw f8, KVM_ARCH_FP_F_F8(a0)
fsw f9, KVM_ARCH_FP_F_F9(a0)
fsw f10, KVM_ARCH_FP_F_F10(a0)
fsw f11, KVM_ARCH_FP_F_F11(a0)
fsw f12, KVM_ARCH_FP_F_F12(a0)
fsw f13, KVM_ARCH_FP_F_F13(a0)
fsw f14, KVM_ARCH_FP_F_F14(a0)
fsw f15, KVM_ARCH_FP_F_F15(a0)
fsw f16, KVM_ARCH_FP_F_F16(a0)
fsw f17, KVM_ARCH_FP_F_F17(a0)
fsw f18, KVM_ARCH_FP_F_F18(a0)
fsw f19, KVM_ARCH_FP_F_F19(a0)
fsw f20, KVM_ARCH_FP_F_F20(a0)
fsw f21, KVM_ARCH_FP_F_F21(a0)
fsw f22, KVM_ARCH_FP_F_F22(a0)
fsw f23, KVM_ARCH_FP_F_F23(a0)
fsw f24, KVM_ARCH_FP_F_F24(a0)
fsw f25, KVM_ARCH_FP_F_F25(a0)
fsw f26, KVM_ARCH_FP_F_F26(a0)
fsw f27, KVM_ARCH_FP_F_F27(a0)
fsw f28, KVM_ARCH_FP_F_F28(a0)
fsw f29, KVM_ARCH_FP_F_F29(a0)
fsw f30, KVM_ARCH_FP_F_F30(a0)
fsw f31, KVM_ARCH_FP_F_F31(a0)
sw t0, KVM_ARCH_FP_F_FCSR(a0)
csrw CSR_SSTATUS, t2
ret
.align 3
.global __kvm_riscv_fp_d_save
__kvm_riscv_fp_d_save:
csrr t2, CSR_SSTATUS
li t1, SR_FS
csrs CSR_SSTATUS, t1
frcsr t0
fsd f0, KVM_ARCH_FP_D_F0(a0)
fsd f1, KVM_ARCH_FP_D_F1(a0)
fsd f2, KVM_ARCH_FP_D_F2(a0)
fsd f3, KVM_ARCH_FP_D_F3(a0)
fsd f4, KVM_ARCH_FP_D_F4(a0)
fsd f5, KVM_ARCH_FP_D_F5(a0)
fsd f6, KVM_ARCH_FP_D_F6(a0)
fsd f7, KVM_ARCH_FP_D_F7(a0)
fsd f8, KVM_ARCH_FP_D_F8(a0)
fsd f9, KVM_ARCH_FP_D_F9(a0)
fsd f10, KVM_ARCH_FP_D_F10(a0)
fsd f11, KVM_ARCH_FP_D_F11(a0)
fsd f12, KVM_ARCH_FP_D_F12(a0)
fsd f13, KVM_ARCH_FP_D_F13(a0)
fsd f14, KVM_ARCH_FP_D_F14(a0)
fsd f15, KVM_ARCH_FP_D_F15(a0)
fsd f16, KVM_ARCH_FP_D_F16(a0)
fsd f17, KVM_ARCH_FP_D_F17(a0)
fsd f18, KVM_ARCH_FP_D_F18(a0)
fsd f19, KVM_ARCH_FP_D_F19(a0)
fsd f20, KVM_ARCH_FP_D_F20(a0)
fsd f21, KVM_ARCH_FP_D_F21(a0)
fsd f22, KVM_ARCH_FP_D_F22(a0)
fsd f23, KVM_ARCH_FP_D_F23(a0)
fsd f24, KVM_ARCH_FP_D_F24(a0)
fsd f25, KVM_ARCH_FP_D_F25(a0)
fsd f26, KVM_ARCH_FP_D_F26(a0)
fsd f27, KVM_ARCH_FP_D_F27(a0)
fsd f28, KVM_ARCH_FP_D_F28(a0)
fsd f29, KVM_ARCH_FP_D_F29(a0)
fsd f30, KVM_ARCH_FP_D_F30(a0)
fsd f31, KVM_ARCH_FP_D_F31(a0)
sw t0, KVM_ARCH_FP_D_FCSR(a0)
csrw CSR_SSTATUS, t2
ret
.align 3
.global __kvm_riscv_fp_f_restore
__kvm_riscv_fp_f_restore:
csrr t2, CSR_SSTATUS
li t1, SR_FS
lw t0, KVM_ARCH_FP_F_FCSR(a0)
csrs CSR_SSTATUS, t1
flw f0, KVM_ARCH_FP_F_F0(a0)
flw f1, KVM_ARCH_FP_F_F1(a0)
flw f2, KVM_ARCH_FP_F_F2(a0)
flw f3, KVM_ARCH_FP_F_F3(a0)
flw f4, KVM_ARCH_FP_F_F4(a0)
flw f5, KVM_ARCH_FP_F_F5(a0)
flw f6, KVM_ARCH_FP_F_F6(a0)
flw f7, KVM_ARCH_FP_F_F7(a0)
flw f8, KVM_ARCH_FP_F_F8(a0)
flw f9, KVM_ARCH_FP_F_F9(a0)
flw f10, KVM_ARCH_FP_F_F10(a0)
flw f11, KVM_ARCH_FP_F_F11(a0)
flw f12, KVM_ARCH_FP_F_F12(a0)
flw f13, KVM_ARCH_FP_F_F13(a0)
flw f14, KVM_ARCH_FP_F_F14(a0)
flw f15, KVM_ARCH_FP_F_F15(a0)
flw f16, KVM_ARCH_FP_F_F16(a0)
flw f17, KVM_ARCH_FP_F_F17(a0)
flw f18, KVM_ARCH_FP_F_F18(a0)
flw f19, KVM_ARCH_FP_F_F19(a0)
flw f20, KVM_ARCH_FP_F_F20(a0)
flw f21, KVM_ARCH_FP_F_F21(a0)
flw f22, KVM_ARCH_FP_F_F22(a0)
flw f23, KVM_ARCH_FP_F_F23(a0)
flw f24, KVM_ARCH_FP_F_F24(a0)
flw f25, KVM_ARCH_FP_F_F25(a0)
flw f26, KVM_ARCH_FP_F_F26(a0)
flw f27, KVM_ARCH_FP_F_F27(a0)
flw f28, KVM_ARCH_FP_F_F28(a0)
flw f29, KVM_ARCH_FP_F_F29(a0)
flw f30, KVM_ARCH_FP_F_F30(a0)
flw f31, KVM_ARCH_FP_F_F31(a0)
fscsr t0
csrw CSR_SSTATUS, t2
ret
.align 3
.global __kvm_riscv_fp_d_restore
__kvm_riscv_fp_d_restore:
csrr t2, CSR_SSTATUS
li t1, SR_FS
lw t0, KVM_ARCH_FP_D_FCSR(a0)
csrs CSR_SSTATUS, t1
fld f0, KVM_ARCH_FP_D_F0(a0)
fld f1, KVM_ARCH_FP_D_F1(a0)
fld f2, KVM_ARCH_FP_D_F2(a0)
fld f3, KVM_ARCH_FP_D_F3(a0)
fld f4, KVM_ARCH_FP_D_F4(a0)
fld f5, KVM_ARCH_FP_D_F5(a0)
fld f6, KVM_ARCH_FP_D_F6(a0)
fld f7, KVM_ARCH_FP_D_F7(a0)
fld f8, KVM_ARCH_FP_D_F8(a0)
fld f9, KVM_ARCH_FP_D_F9(a0)
fld f10, KVM_ARCH_FP_D_F10(a0)
fld f11, KVM_ARCH_FP_D_F11(a0)
fld f12, KVM_ARCH_FP_D_F12(a0)
fld f13, KVM_ARCH_FP_D_F13(a0)
fld f14, KVM_ARCH_FP_D_F14(a0)
fld f15, KVM_ARCH_FP_D_F15(a0)
fld f16, KVM_ARCH_FP_D_F16(a0)
fld f17, KVM_ARCH_FP_D_F17(a0)
fld f18, KVM_ARCH_FP_D_F18(a0)
fld f19, KVM_ARCH_FP_D_F19(a0)
fld f20, KVM_ARCH_FP_D_F20(a0)
fld f21, KVM_ARCH_FP_D_F21(a0)
fld f22, KVM_ARCH_FP_D_F22(a0)
fld f23, KVM_ARCH_FP_D_F23(a0)
fld f24, KVM_ARCH_FP_D_F24(a0)
fld f25, KVM_ARCH_FP_D_F25(a0)
fld f26, KVM_ARCH_FP_D_F26(a0)
fld f27, KVM_ARCH_FP_D_F27(a0)
fld f28, KVM_ARCH_FP_D_F28(a0)
fld f29, KVM_ARCH_FP_D_F29(a0)
fld f30, KVM_ARCH_FP_D_F30(a0)
fld f31, KVM_ARCH_FP_D_F31(a0)
fscsr t0
csrw CSR_SSTATUS, t2
ret
#endif
Reference in New Issue View Git Blame Copy Permalink