xref: /openbmc/linux/arch/riscv/kvm/vcpu_switch.S (revision 9a29f5fc)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2019 Western Digital Corporation or its affiliates.
4 *
5 * Authors:
6 *     Anup Patel <anup.patel@wdc.com>
7 */
8
9#include <linux/linkage.h>
10#include <asm/asm.h>
11#include <asm/asm-offsets.h>
12#include <asm/csr.h>
13
14	.text
15	.altmacro
16	.option norelax
17
18ENTRY(__kvm_riscv_switch_to)
19	/* Save Host GPRs (except A0 and T0-T6) */
20	REG_S	ra, (KVM_ARCH_HOST_RA)(a0)
21	REG_S	sp, (KVM_ARCH_HOST_SP)(a0)
22	REG_S	gp, (KVM_ARCH_HOST_GP)(a0)
23	REG_S	tp, (KVM_ARCH_HOST_TP)(a0)
24	REG_S	s0, (KVM_ARCH_HOST_S0)(a0)
25	REG_S	s1, (KVM_ARCH_HOST_S1)(a0)
26	REG_S	a1, (KVM_ARCH_HOST_A1)(a0)
27	REG_S	a2, (KVM_ARCH_HOST_A2)(a0)
28	REG_S	a3, (KVM_ARCH_HOST_A3)(a0)
29	REG_S	a4, (KVM_ARCH_HOST_A4)(a0)
30	REG_S	a5, (KVM_ARCH_HOST_A5)(a0)
31	REG_S	a6, (KVM_ARCH_HOST_A6)(a0)
32	REG_S	a7, (KVM_ARCH_HOST_A7)(a0)
33	REG_S	s2, (KVM_ARCH_HOST_S2)(a0)
34	REG_S	s3, (KVM_ARCH_HOST_S3)(a0)
35	REG_S	s4, (KVM_ARCH_HOST_S4)(a0)
36	REG_S	s5, (KVM_ARCH_HOST_S5)(a0)
37	REG_S	s6, (KVM_ARCH_HOST_S6)(a0)
38	REG_S	s7, (KVM_ARCH_HOST_S7)(a0)
39	REG_S	s8, (KVM_ARCH_HOST_S8)(a0)
40	REG_S	s9, (KVM_ARCH_HOST_S9)(a0)
41	REG_S	s10, (KVM_ARCH_HOST_S10)(a0)
42	REG_S	s11, (KVM_ARCH_HOST_S11)(a0)
43
44	/* Load Guest CSR values */
45	REG_L	t0, (KVM_ARCH_GUEST_SSTATUS)(a0)
46	REG_L	t1, (KVM_ARCH_GUEST_HSTATUS)(a0)
47	REG_L	t2, (KVM_ARCH_GUEST_SCOUNTEREN)(a0)
48	la	t4, __kvm_switch_return
49	REG_L	t5, (KVM_ARCH_GUEST_SEPC)(a0)
50
51	/* Save Host and Restore Guest SSTATUS */
52	csrrw	t0, CSR_SSTATUS, t0
53
54	/* Save Host and Restore Guest HSTATUS */
55	csrrw	t1, CSR_HSTATUS, t1
56
57	/* Save Host and Restore Guest SCOUNTEREN */
58	csrrw	t2, CSR_SCOUNTEREN, t2
59
60	/* Save Host STVEC and change it to return path */
61	csrrw	t4, CSR_STVEC, t4
62
63	/* Save Host SSCRATCH and change it to struct kvm_vcpu_arch pointer */
64	csrrw	t3, CSR_SSCRATCH, a0
65
66	/* Restore Guest SEPC */
67	csrw	CSR_SEPC, t5
68
69	/* Store Host CSR values */
70	REG_S	t0, (KVM_ARCH_HOST_SSTATUS)(a0)
71	REG_S	t1, (KVM_ARCH_HOST_HSTATUS)(a0)
72	REG_S	t2, (KVM_ARCH_HOST_SCOUNTEREN)(a0)
73	REG_S	t3, (KVM_ARCH_HOST_SSCRATCH)(a0)
74	REG_S	t4, (KVM_ARCH_HOST_STVEC)(a0)
75
76	/* Restore Guest GPRs (except A0) */
77	REG_L	ra, (KVM_ARCH_GUEST_RA)(a0)
78	REG_L	sp, (KVM_ARCH_GUEST_SP)(a0)
79	REG_L	gp, (KVM_ARCH_GUEST_GP)(a0)
80	REG_L	tp, (KVM_ARCH_GUEST_TP)(a0)
81	REG_L	t0, (KVM_ARCH_GUEST_T0)(a0)
82	REG_L	t1, (KVM_ARCH_GUEST_T1)(a0)
83	REG_L	t2, (KVM_ARCH_GUEST_T2)(a0)
84	REG_L	s0, (KVM_ARCH_GUEST_S0)(a0)
85	REG_L	s1, (KVM_ARCH_GUEST_S1)(a0)
86	REG_L	a1, (KVM_ARCH_GUEST_A1)(a0)
87	REG_L	a2, (KVM_ARCH_GUEST_A2)(a0)
88	REG_L	a3, (KVM_ARCH_GUEST_A3)(a0)
89	REG_L	a4, (KVM_ARCH_GUEST_A4)(a0)
90	REG_L	a5, (KVM_ARCH_GUEST_A5)(a0)
91	REG_L	a6, (KVM_ARCH_GUEST_A6)(a0)
92	REG_L	a7, (KVM_ARCH_GUEST_A7)(a0)
93	REG_L	s2, (KVM_ARCH_GUEST_S2)(a0)
94	REG_L	s3, (KVM_ARCH_GUEST_S3)(a0)
95	REG_L	s4, (KVM_ARCH_GUEST_S4)(a0)
96	REG_L	s5, (KVM_ARCH_GUEST_S5)(a0)
97	REG_L	s6, (KVM_ARCH_GUEST_S6)(a0)
98	REG_L	s7, (KVM_ARCH_GUEST_S7)(a0)
99	REG_L	s8, (KVM_ARCH_GUEST_S8)(a0)
100	REG_L	s9, (KVM_ARCH_GUEST_S9)(a0)
101	REG_L	s10, (KVM_ARCH_GUEST_S10)(a0)
102	REG_L	s11, (KVM_ARCH_GUEST_S11)(a0)
103	REG_L	t3, (KVM_ARCH_GUEST_T3)(a0)
104	REG_L	t4, (KVM_ARCH_GUEST_T4)(a0)
105	REG_L	t5, (KVM_ARCH_GUEST_T5)(a0)
106	REG_L	t6, (KVM_ARCH_GUEST_T6)(a0)
107
108	/* Restore Guest A0 */
109	REG_L	a0, (KVM_ARCH_GUEST_A0)(a0)
110
111	/* Resume Guest */
112	sret
113
114	/* Back to Host */
115	.align 2
116__kvm_switch_return:
117	/* Swap Guest A0 with SSCRATCH */
118	csrrw	a0, CSR_SSCRATCH, a0
119
120	/* Save Guest GPRs (except A0) */
121	REG_S	ra, (KVM_ARCH_GUEST_RA)(a0)
122	REG_S	sp, (KVM_ARCH_GUEST_SP)(a0)
123	REG_S	gp, (KVM_ARCH_GUEST_GP)(a0)
124	REG_S	tp, (KVM_ARCH_GUEST_TP)(a0)
125	REG_S	t0, (KVM_ARCH_GUEST_T0)(a0)
126	REG_S	t1, (KVM_ARCH_GUEST_T1)(a0)
127	REG_S	t2, (KVM_ARCH_GUEST_T2)(a0)
128	REG_S	s0, (KVM_ARCH_GUEST_S0)(a0)
129	REG_S	s1, (KVM_ARCH_GUEST_S1)(a0)
130	REG_S	a1, (KVM_ARCH_GUEST_A1)(a0)
131	REG_S	a2, (KVM_ARCH_GUEST_A2)(a0)
132	REG_S	a3, (KVM_ARCH_GUEST_A3)(a0)
133	REG_S	a4, (KVM_ARCH_GUEST_A4)(a0)
134	REG_S	a5, (KVM_ARCH_GUEST_A5)(a0)
135	REG_S	a6, (KVM_ARCH_GUEST_A6)(a0)
136	REG_S	a7, (KVM_ARCH_GUEST_A7)(a0)
137	REG_S	s2, (KVM_ARCH_GUEST_S2)(a0)
138	REG_S	s3, (KVM_ARCH_GUEST_S3)(a0)
139	REG_S	s4, (KVM_ARCH_GUEST_S4)(a0)
140	REG_S	s5, (KVM_ARCH_GUEST_S5)(a0)
141	REG_S	s6, (KVM_ARCH_GUEST_S6)(a0)
142	REG_S	s7, (KVM_ARCH_GUEST_S7)(a0)
143	REG_S	s8, (KVM_ARCH_GUEST_S8)(a0)
144	REG_S	s9, (KVM_ARCH_GUEST_S9)(a0)
145	REG_S	s10, (KVM_ARCH_GUEST_S10)(a0)
146	REG_S	s11, (KVM_ARCH_GUEST_S11)(a0)
147	REG_S	t3, (KVM_ARCH_GUEST_T3)(a0)
148	REG_S	t4, (KVM_ARCH_GUEST_T4)(a0)
149	REG_S	t5, (KVM_ARCH_GUEST_T5)(a0)
150	REG_S	t6, (KVM_ARCH_GUEST_T6)(a0)
151
152	/* Load Host CSR values */
153	REG_L	t1, (KVM_ARCH_HOST_STVEC)(a0)
154	REG_L	t2, (KVM_ARCH_HOST_SSCRATCH)(a0)
155	REG_L	t3, (KVM_ARCH_HOST_SCOUNTEREN)(a0)
156	REG_L	t4, (KVM_ARCH_HOST_HSTATUS)(a0)
157	REG_L	t5, (KVM_ARCH_HOST_SSTATUS)(a0)
158
159	/* Save Guest SEPC */
160	csrr	t0, CSR_SEPC
161
162	/* Save Guest A0 and Restore Host SSCRATCH */
163	csrrw	t2, CSR_SSCRATCH, t2
164
165	/* Restore Host STVEC */
166	csrw	CSR_STVEC, t1
167
168	/* Save Guest and Restore Host SCOUNTEREN */
169	csrrw	t3, CSR_SCOUNTEREN, t3
170
171	/* Save Guest and Restore Host HSTATUS */
172	csrrw	t4, CSR_HSTATUS, t4
173
174	/* Save Guest and Restore Host SSTATUS */
175	csrrw	t5, CSR_SSTATUS, t5
176
177	/* Store Guest CSR values */
178	REG_S	t0, (KVM_ARCH_GUEST_SEPC)(a0)
179	REG_S	t2, (KVM_ARCH_GUEST_A0)(a0)
180	REG_S	t3, (KVM_ARCH_GUEST_SCOUNTEREN)(a0)
181	REG_S	t4, (KVM_ARCH_GUEST_HSTATUS)(a0)
182	REG_S	t5, (KVM_ARCH_GUEST_SSTATUS)(a0)
183
184	/* Restore Host GPRs (except A0 and T0-T6) */
185	REG_L	ra, (KVM_ARCH_HOST_RA)(a0)
186	REG_L	sp, (KVM_ARCH_HOST_SP)(a0)
187	REG_L	gp, (KVM_ARCH_HOST_GP)(a0)
188	REG_L	tp, (KVM_ARCH_HOST_TP)(a0)
189	REG_L	s0, (KVM_ARCH_HOST_S0)(a0)
190	REG_L	s1, (KVM_ARCH_HOST_S1)(a0)
191	REG_L	a1, (KVM_ARCH_HOST_A1)(a0)
192	REG_L	a2, (KVM_ARCH_HOST_A2)(a0)
193	REG_L	a3, (KVM_ARCH_HOST_A3)(a0)
194	REG_L	a4, (KVM_ARCH_HOST_A4)(a0)
195	REG_L	a5, (KVM_ARCH_HOST_A5)(a0)
196	REG_L	a6, (KVM_ARCH_HOST_A6)(a0)
197	REG_L	a7, (KVM_ARCH_HOST_A7)(a0)
198	REG_L	s2, (KVM_ARCH_HOST_S2)(a0)
199	REG_L	s3, (KVM_ARCH_HOST_S3)(a0)
200	REG_L	s4, (KVM_ARCH_HOST_S4)(a0)
201	REG_L	s5, (KVM_ARCH_HOST_S5)(a0)
202	REG_L	s6, (KVM_ARCH_HOST_S6)(a0)
203	REG_L	s7, (KVM_ARCH_HOST_S7)(a0)
204	REG_L	s8, (KVM_ARCH_HOST_S8)(a0)
205	REG_L	s9, (KVM_ARCH_HOST_S9)(a0)
206	REG_L	s10, (KVM_ARCH_HOST_S10)(a0)
207	REG_L	s11, (KVM_ARCH_HOST_S11)(a0)
208
209	/* Return to C code */
210	ret
211ENDPROC(__kvm_riscv_switch_to)
212
213ENTRY(__kvm_riscv_unpriv_trap)
214	/*
215	 * We assume that faulting unpriv load/store instruction is
216	 * 4-byte long and blindly increment SEPC by 4.
217	 *
218	 * The trap details will be saved at address pointed by 'A0'
219	 * register and we use 'A1' register as temporary.
220	 */
221	csrr	a1, CSR_SEPC
222	REG_S	a1, (KVM_ARCH_TRAP_SEPC)(a0)
223	addi	a1, a1, 4
224	csrw	CSR_SEPC, a1
225	csrr	a1, CSR_SCAUSE
226	REG_S	a1, (KVM_ARCH_TRAP_SCAUSE)(a0)
227	csrr	a1, CSR_STVAL
228	REG_S	a1, (KVM_ARCH_TRAP_STVAL)(a0)
229	csrr	a1, CSR_HTVAL
230	REG_S	a1, (KVM_ARCH_TRAP_HTVAL)(a0)
231	csrr	a1, CSR_HTINST
232	REG_S	a1, (KVM_ARCH_TRAP_HTINST)(a0)
233	sret
234ENDPROC(__kvm_riscv_unpriv_trap)
235
236#ifdef	CONFIG_FPU
237	.align 3
238	.global __kvm_riscv_fp_f_save
239__kvm_riscv_fp_f_save:
240	csrr t2, CSR_SSTATUS
241	li t1, SR_FS
242	csrs CSR_SSTATUS, t1
243	frcsr t0
244	fsw f0,  KVM_ARCH_FP_F_F0(a0)
245	fsw f1,  KVM_ARCH_FP_F_F1(a0)
246	fsw f2,  KVM_ARCH_FP_F_F2(a0)
247	fsw f3,  KVM_ARCH_FP_F_F3(a0)
248	fsw f4,  KVM_ARCH_FP_F_F4(a0)
249	fsw f5,  KVM_ARCH_FP_F_F5(a0)
250	fsw f6,  KVM_ARCH_FP_F_F6(a0)
251	fsw f7,  KVM_ARCH_FP_F_F7(a0)
252	fsw f8,  KVM_ARCH_FP_F_F8(a0)
253	fsw f9,  KVM_ARCH_FP_F_F9(a0)
254	fsw f10, KVM_ARCH_FP_F_F10(a0)
255	fsw f11, KVM_ARCH_FP_F_F11(a0)
256	fsw f12, KVM_ARCH_FP_F_F12(a0)
257	fsw f13, KVM_ARCH_FP_F_F13(a0)
258	fsw f14, KVM_ARCH_FP_F_F14(a0)
259	fsw f15, KVM_ARCH_FP_F_F15(a0)
260	fsw f16, KVM_ARCH_FP_F_F16(a0)
261	fsw f17, KVM_ARCH_FP_F_F17(a0)
262	fsw f18, KVM_ARCH_FP_F_F18(a0)
263	fsw f19, KVM_ARCH_FP_F_F19(a0)
264	fsw f20, KVM_ARCH_FP_F_F20(a0)
265	fsw f21, KVM_ARCH_FP_F_F21(a0)
266	fsw f22, KVM_ARCH_FP_F_F22(a0)
267	fsw f23, KVM_ARCH_FP_F_F23(a0)
268	fsw f24, KVM_ARCH_FP_F_F24(a0)
269	fsw f25, KVM_ARCH_FP_F_F25(a0)
270	fsw f26, KVM_ARCH_FP_F_F26(a0)
271	fsw f27, KVM_ARCH_FP_F_F27(a0)
272	fsw f28, KVM_ARCH_FP_F_F28(a0)
273	fsw f29, KVM_ARCH_FP_F_F29(a0)
274	fsw f30, KVM_ARCH_FP_F_F30(a0)
275	fsw f31, KVM_ARCH_FP_F_F31(a0)
276	sw t0, KVM_ARCH_FP_F_FCSR(a0)
277	csrw CSR_SSTATUS, t2
278	ret
279
280	.align 3
281	.global __kvm_riscv_fp_d_save
282__kvm_riscv_fp_d_save:
283	csrr t2, CSR_SSTATUS
284	li t1, SR_FS
285	csrs CSR_SSTATUS, t1
286	frcsr t0
287	fsd f0,  KVM_ARCH_FP_D_F0(a0)
288	fsd f1,  KVM_ARCH_FP_D_F1(a0)
289	fsd f2,  KVM_ARCH_FP_D_F2(a0)
290	fsd f3,  KVM_ARCH_FP_D_F3(a0)
291	fsd f4,  KVM_ARCH_FP_D_F4(a0)
292	fsd f5,  KVM_ARCH_FP_D_F5(a0)
293	fsd f6,  KVM_ARCH_FP_D_F6(a0)
294	fsd f7,  KVM_ARCH_FP_D_F7(a0)
295	fsd f8,  KVM_ARCH_FP_D_F8(a0)
296	fsd f9,  KVM_ARCH_FP_D_F9(a0)
297	fsd f10, KVM_ARCH_FP_D_F10(a0)
298	fsd f11, KVM_ARCH_FP_D_F11(a0)
299	fsd f12, KVM_ARCH_FP_D_F12(a0)
300	fsd f13, KVM_ARCH_FP_D_F13(a0)
301	fsd f14, KVM_ARCH_FP_D_F14(a0)
302	fsd f15, KVM_ARCH_FP_D_F15(a0)
303	fsd f16, KVM_ARCH_FP_D_F16(a0)
304	fsd f17, KVM_ARCH_FP_D_F17(a0)
305	fsd f18, KVM_ARCH_FP_D_F18(a0)
306	fsd f19, KVM_ARCH_FP_D_F19(a0)
307	fsd f20, KVM_ARCH_FP_D_F20(a0)
308	fsd f21, KVM_ARCH_FP_D_F21(a0)
309	fsd f22, KVM_ARCH_FP_D_F22(a0)
310	fsd f23, KVM_ARCH_FP_D_F23(a0)
311	fsd f24, KVM_ARCH_FP_D_F24(a0)
312	fsd f25, KVM_ARCH_FP_D_F25(a0)
313	fsd f26, KVM_ARCH_FP_D_F26(a0)
314	fsd f27, KVM_ARCH_FP_D_F27(a0)
315	fsd f28, KVM_ARCH_FP_D_F28(a0)
316	fsd f29, KVM_ARCH_FP_D_F29(a0)
317	fsd f30, KVM_ARCH_FP_D_F30(a0)
318	fsd f31, KVM_ARCH_FP_D_F31(a0)
319	sw t0, KVM_ARCH_FP_D_FCSR(a0)
320	csrw CSR_SSTATUS, t2
321	ret
322
323	.align 3
324	.global __kvm_riscv_fp_f_restore
325__kvm_riscv_fp_f_restore:
326	csrr t2, CSR_SSTATUS
327	li t1, SR_FS
328	lw t0, KVM_ARCH_FP_F_FCSR(a0)
329	csrs CSR_SSTATUS, t1
330	flw f0,  KVM_ARCH_FP_F_F0(a0)
331	flw f1,  KVM_ARCH_FP_F_F1(a0)
332	flw f2,  KVM_ARCH_FP_F_F2(a0)
333	flw f3,  KVM_ARCH_FP_F_F3(a0)
334	flw f4,  KVM_ARCH_FP_F_F4(a0)
335	flw f5,  KVM_ARCH_FP_F_F5(a0)
336	flw f6,  KVM_ARCH_FP_F_F6(a0)
337	flw f7,  KVM_ARCH_FP_F_F7(a0)
338	flw f8,  KVM_ARCH_FP_F_F8(a0)
339	flw f9,  KVM_ARCH_FP_F_F9(a0)
340	flw f10, KVM_ARCH_FP_F_F10(a0)
341	flw f11, KVM_ARCH_FP_F_F11(a0)
342	flw f12, KVM_ARCH_FP_F_F12(a0)
343	flw f13, KVM_ARCH_FP_F_F13(a0)
344	flw f14, KVM_ARCH_FP_F_F14(a0)
345	flw f15, KVM_ARCH_FP_F_F15(a0)
346	flw f16, KVM_ARCH_FP_F_F16(a0)
347	flw f17, KVM_ARCH_FP_F_F17(a0)
348	flw f18, KVM_ARCH_FP_F_F18(a0)
349	flw f19, KVM_ARCH_FP_F_F19(a0)
350	flw f20, KVM_ARCH_FP_F_F20(a0)
351	flw f21, KVM_ARCH_FP_F_F21(a0)
352	flw f22, KVM_ARCH_FP_F_F22(a0)
353	flw f23, KVM_ARCH_FP_F_F23(a0)
354	flw f24, KVM_ARCH_FP_F_F24(a0)
355	flw f25, KVM_ARCH_FP_F_F25(a0)
356	flw f26, KVM_ARCH_FP_F_F26(a0)
357	flw f27, KVM_ARCH_FP_F_F27(a0)
358	flw f28, KVM_ARCH_FP_F_F28(a0)
359	flw f29, KVM_ARCH_FP_F_F29(a0)
360	flw f30, KVM_ARCH_FP_F_F30(a0)
361	flw f31, KVM_ARCH_FP_F_F31(a0)
362	fscsr t0
363	csrw CSR_SSTATUS, t2
364	ret
365
366	.align 3
367	.global __kvm_riscv_fp_d_restore
368__kvm_riscv_fp_d_restore:
369	csrr t2, CSR_SSTATUS
370	li t1, SR_FS
371	lw t0, KVM_ARCH_FP_D_FCSR(a0)
372	csrs CSR_SSTATUS, t1
373	fld f0,  KVM_ARCH_FP_D_F0(a0)
374	fld f1,  KVM_ARCH_FP_D_F1(a0)
375	fld f2,  KVM_ARCH_FP_D_F2(a0)
376	fld f3,  KVM_ARCH_FP_D_F3(a0)
377	fld f4,  KVM_ARCH_FP_D_F4(a0)
378	fld f5,  KVM_ARCH_FP_D_F5(a0)
379	fld f6,  KVM_ARCH_FP_D_F6(a0)
380	fld f7,  KVM_ARCH_FP_D_F7(a0)
381	fld f8,  KVM_ARCH_FP_D_F8(a0)
382	fld f9,  KVM_ARCH_FP_D_F9(a0)
383	fld f10, KVM_ARCH_FP_D_F10(a0)
384	fld f11, KVM_ARCH_FP_D_F11(a0)
385	fld f12, KVM_ARCH_FP_D_F12(a0)
386	fld f13, KVM_ARCH_FP_D_F13(a0)
387	fld f14, KVM_ARCH_FP_D_F14(a0)
388	fld f15, KVM_ARCH_FP_D_F15(a0)
389	fld f16, KVM_ARCH_FP_D_F16(a0)
390	fld f17, KVM_ARCH_FP_D_F17(a0)
391	fld f18, KVM_ARCH_FP_D_F18(a0)
392	fld f19, KVM_ARCH_FP_D_F19(a0)
393	fld f20, KVM_ARCH_FP_D_F20(a0)
394	fld f21, KVM_ARCH_FP_D_F21(a0)
395	fld f22, KVM_ARCH_FP_D_F22(a0)
396	fld f23, KVM_ARCH_FP_D_F23(a0)
397	fld f24, KVM_ARCH_FP_D_F24(a0)
398	fld f25, KVM_ARCH_FP_D_F25(a0)
399	fld f26, KVM_ARCH_FP_D_F26(a0)
400	fld f27, KVM_ARCH_FP_D_F27(a0)
401	fld f28, KVM_ARCH_FP_D_F28(a0)
402	fld f29, KVM_ARCH_FP_D_F29(a0)
403	fld f30, KVM_ARCH_FP_D_F30(a0)
404	fld f31, KVM_ARCH_FP_D_F31(a0)
405	fscsr t0
406	csrw CSR_SSTATUS, t2
407	ret
408#endif
409