xref: /linux/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h (revision 63eb28bb1402891b1ad2be02a530f29a9dd7f1cd)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012-2015 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  */
6 
7 #ifndef __ARM64_KVM_HYP_SYSREG_SR_H__
8 #define __ARM64_KVM_HYP_SYSREG_SR_H__
9 
10 #include <linux/compiler.h>
11 #include <linux/kvm_host.h>
12 
13 #include <asm/kprobes.h>
14 #include <asm/kvm_asm.h>
15 #include <asm/kvm_emulate.h>
16 #include <asm/kvm_hyp.h>
17 #include <asm/kvm_mmu.h>
18 
19 static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt);
20 
ctxt_to_vcpu(struct kvm_cpu_context * ctxt)21 static inline struct kvm_vcpu *ctxt_to_vcpu(struct kvm_cpu_context *ctxt)
22 {
23 	struct kvm_vcpu *vcpu = ctxt->__hyp_running_vcpu;
24 
25 	if (!vcpu)
26 		vcpu = container_of(ctxt, struct kvm_vcpu, arch.ctxt);
27 
28 	return vcpu;
29 }
30 
ctxt_is_guest(struct kvm_cpu_context * ctxt)31 static inline bool ctxt_is_guest(struct kvm_cpu_context *ctxt)
32 {
33 	return host_data_ptr(host_ctxt) != ctxt;
34 }
35 
ctxt_mdscr_el1(struct kvm_cpu_context * ctxt)36 static inline u64 *ctxt_mdscr_el1(struct kvm_cpu_context *ctxt)
37 {
38 	struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
39 
40 	if (ctxt_is_guest(ctxt) && kvm_host_owns_debug_regs(vcpu))
41 		return &vcpu->arch.external_mdscr_el1;
42 
43 	return &ctxt_sys_reg(ctxt, MDSCR_EL1);
44 }
45 
ctxt_midr_el1(struct kvm_cpu_context * ctxt)46 static inline u64 ctxt_midr_el1(struct kvm_cpu_context *ctxt)
47 {
48 	struct kvm *kvm = kern_hyp_va(ctxt_to_vcpu(ctxt)->kvm);
49 
50 	if (!(ctxt_is_guest(ctxt) &&
51 	      test_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &kvm->arch.flags)))
52 		return read_cpuid_id();
53 
54 	return kvm_read_vm_id_reg(kvm, SYS_MIDR_EL1);
55 }
56 
__sysreg_save_common_state(struct kvm_cpu_context * ctxt)57 static inline void __sysreg_save_common_state(struct kvm_cpu_context *ctxt)
58 {
59 	*ctxt_mdscr_el1(ctxt)	= read_sysreg(mdscr_el1);
60 
61 	// POR_EL0 can affect uaccess, so must be saved/restored early.
62 	if (ctxt_has_s1poe(ctxt))
63 		ctxt_sys_reg(ctxt, POR_EL0)	= read_sysreg_s(SYS_POR_EL0);
64 }
65 
__sysreg_save_user_state(struct kvm_cpu_context * ctxt)66 static inline void __sysreg_save_user_state(struct kvm_cpu_context *ctxt)
67 {
68 	ctxt_sys_reg(ctxt, TPIDR_EL0)	= read_sysreg(tpidr_el0);
69 	ctxt_sys_reg(ctxt, TPIDRRO_EL0)	= read_sysreg(tpidrro_el0);
70 }
71 
ctxt_has_mte(struct kvm_cpu_context * ctxt)72 static inline bool ctxt_has_mte(struct kvm_cpu_context *ctxt)
73 {
74 	struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
75 
76 	return kvm_has_mte(kern_hyp_va(vcpu->kvm));
77 }
78 
ctxt_has_s1pie(struct kvm_cpu_context * ctxt)79 static inline bool ctxt_has_s1pie(struct kvm_cpu_context *ctxt)
80 {
81 	struct kvm_vcpu *vcpu;
82 
83 	if (!cpus_have_final_cap(ARM64_HAS_S1PIE))
84 		return false;
85 
86 	vcpu = ctxt_to_vcpu(ctxt);
87 	return kvm_has_s1pie(kern_hyp_va(vcpu->kvm));
88 }
89 
ctxt_has_tcrx(struct kvm_cpu_context * ctxt)90 static inline bool ctxt_has_tcrx(struct kvm_cpu_context *ctxt)
91 {
92 	struct kvm_vcpu *vcpu;
93 
94 	if (!cpus_have_final_cap(ARM64_HAS_TCR2))
95 		return false;
96 
97 	vcpu = ctxt_to_vcpu(ctxt);
98 	return kvm_has_tcr2(kern_hyp_va(vcpu->kvm));
99 }
100 
ctxt_has_s1poe(struct kvm_cpu_context * ctxt)101 static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt)
102 {
103 	struct kvm_vcpu *vcpu;
104 
105 	if (!system_supports_poe())
106 		return false;
107 
108 	vcpu = ctxt_to_vcpu(ctxt);
109 	return kvm_has_s1poe(kern_hyp_va(vcpu->kvm));
110 }
111 
ctxt_has_ras(struct kvm_cpu_context * ctxt)112 static inline bool ctxt_has_ras(struct kvm_cpu_context *ctxt)
113 {
114 	struct kvm_vcpu *vcpu;
115 
116 	if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
117 		return false;
118 
119 	vcpu = ctxt_to_vcpu(ctxt);
120 	return kvm_has_ras(kern_hyp_va(vcpu->kvm));
121 }
122 
ctxt_has_sctlr2(struct kvm_cpu_context * ctxt)123 static inline bool ctxt_has_sctlr2(struct kvm_cpu_context *ctxt)
124 {
125 	struct kvm_vcpu *vcpu;
126 
127 	if (!cpus_have_final_cap(ARM64_HAS_SCTLR2))
128 		return false;
129 
130 	vcpu = ctxt_to_vcpu(ctxt);
131 	return kvm_has_sctlr2(kern_hyp_va(vcpu->kvm));
132 }
133 
__sysreg_save_el1_state(struct kvm_cpu_context * ctxt)134 static inline void __sysreg_save_el1_state(struct kvm_cpu_context *ctxt)
135 {
136 	ctxt_sys_reg(ctxt, SCTLR_EL1)	= read_sysreg_el1(SYS_SCTLR);
137 	ctxt_sys_reg(ctxt, CPACR_EL1)	= read_sysreg_el1(SYS_CPACR);
138 	ctxt_sys_reg(ctxt, TTBR0_EL1)	= read_sysreg_el1(SYS_TTBR0);
139 	ctxt_sys_reg(ctxt, TTBR1_EL1)	= read_sysreg_el1(SYS_TTBR1);
140 	ctxt_sys_reg(ctxt, TCR_EL1)	= read_sysreg_el1(SYS_TCR);
141 	if (ctxt_has_tcrx(ctxt)) {
142 		ctxt_sys_reg(ctxt, TCR2_EL1)	= read_sysreg_el1(SYS_TCR2);
143 
144 		if (ctxt_has_s1pie(ctxt)) {
145 			ctxt_sys_reg(ctxt, PIR_EL1)	= read_sysreg_el1(SYS_PIR);
146 			ctxt_sys_reg(ctxt, PIRE0_EL1)	= read_sysreg_el1(SYS_PIRE0);
147 		}
148 
149 		if (ctxt_has_s1poe(ctxt))
150 			ctxt_sys_reg(ctxt, POR_EL1)	= read_sysreg_el1(SYS_POR);
151 	}
152 	ctxt_sys_reg(ctxt, ESR_EL1)	= read_sysreg_el1(SYS_ESR);
153 	ctxt_sys_reg(ctxt, AFSR0_EL1)	= read_sysreg_el1(SYS_AFSR0);
154 	ctxt_sys_reg(ctxt, AFSR1_EL1)	= read_sysreg_el1(SYS_AFSR1);
155 	ctxt_sys_reg(ctxt, FAR_EL1)	= read_sysreg_el1(SYS_FAR);
156 	ctxt_sys_reg(ctxt, MAIR_EL1)	= read_sysreg_el1(SYS_MAIR);
157 	ctxt_sys_reg(ctxt, VBAR_EL1)	= read_sysreg_el1(SYS_VBAR);
158 	ctxt_sys_reg(ctxt, CONTEXTIDR_EL1) = read_sysreg_el1(SYS_CONTEXTIDR);
159 	ctxt_sys_reg(ctxt, AMAIR_EL1)	= read_sysreg_el1(SYS_AMAIR);
160 	ctxt_sys_reg(ctxt, CNTKCTL_EL1)	= read_sysreg_el1(SYS_CNTKCTL);
161 	ctxt_sys_reg(ctxt, PAR_EL1)	= read_sysreg_par();
162 	ctxt_sys_reg(ctxt, TPIDR_EL1)	= read_sysreg(tpidr_el1);
163 
164 	if (ctxt_has_mte(ctxt)) {
165 		ctxt_sys_reg(ctxt, TFSR_EL1) = read_sysreg_el1(SYS_TFSR);
166 		ctxt_sys_reg(ctxt, TFSRE0_EL1) = read_sysreg_s(SYS_TFSRE0_EL1);
167 	}
168 
169 	ctxt_sys_reg(ctxt, SP_EL1)	= read_sysreg(sp_el1);
170 	ctxt_sys_reg(ctxt, ELR_EL1)	= read_sysreg_el1(SYS_ELR);
171 	ctxt_sys_reg(ctxt, SPSR_EL1)	= read_sysreg_el1(SYS_SPSR);
172 
173 	if (ctxt_has_sctlr2(ctxt))
174 		ctxt_sys_reg(ctxt, SCTLR2_EL1) = read_sysreg_el1(SYS_SCTLR2);
175 }
176 
__sysreg_save_el2_return_state(struct kvm_cpu_context * ctxt)177 static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt)
178 {
179 	ctxt->regs.pc			= read_sysreg_el2(SYS_ELR);
180 	/*
181 	 * Guest PSTATE gets saved at guest fixup time in all
182 	 * cases. We still need to handle the nVHE host side here.
183 	 */
184 	if (!has_vhe() && ctxt->__hyp_running_vcpu)
185 		ctxt->regs.pstate	= read_sysreg_el2(SYS_SPSR);
186 
187 	if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
188 		return;
189 
190 	if (!vserror_state_is_nested(ctxt_to_vcpu(ctxt)))
191 		ctxt_sys_reg(ctxt, DISR_EL1) = read_sysreg_s(SYS_VDISR_EL2);
192 	else if (ctxt_has_ras(ctxt))
193 		ctxt_sys_reg(ctxt, VDISR_EL2) = read_sysreg_s(SYS_VDISR_EL2);
194 }
195 
__sysreg_restore_common_state(struct kvm_cpu_context * ctxt)196 static inline void __sysreg_restore_common_state(struct kvm_cpu_context *ctxt)
197 {
198 	write_sysreg(*ctxt_mdscr_el1(ctxt),  mdscr_el1);
199 
200 	// POR_EL0 can affect uaccess, so must be saved/restored early.
201 	if (ctxt_has_s1poe(ctxt))
202 		write_sysreg_s(ctxt_sys_reg(ctxt, POR_EL0),	SYS_POR_EL0);
203 }
204 
__sysreg_restore_user_state(struct kvm_cpu_context * ctxt)205 static inline void __sysreg_restore_user_state(struct kvm_cpu_context *ctxt)
206 {
207 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL0),	tpidr_el0);
208 	write_sysreg(ctxt_sys_reg(ctxt, TPIDRRO_EL0),	tpidrro_el0);
209 }
210 
__sysreg_restore_el1_state(struct kvm_cpu_context * ctxt,u64 midr,u64 mpidr)211 static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt,
212 					      u64 midr, u64 mpidr)
213 {
214 	write_sysreg(midr,				vpidr_el2);
215 	write_sysreg(mpidr,				vmpidr_el2);
216 
217 	if (has_vhe() ||
218 	    !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
219 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
220 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
221 	} else	if (!ctxt->__hyp_running_vcpu) {
222 		/*
223 		 * Must only be done for guest registers, hence the context
224 		 * test. We're coming from the host, so SCTLR.M is already
225 		 * set. Pairs with nVHE's __activate_traps().
226 		 */
227 		write_sysreg_el1((ctxt_sys_reg(ctxt, TCR_EL1) |
228 				  TCR_EPD1_MASK | TCR_EPD0_MASK),
229 				 SYS_TCR);
230 		isb();
231 	}
232 
233 	write_sysreg_el1(ctxt_sys_reg(ctxt, CPACR_EL1),	SYS_CPACR);
234 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR0_EL1),	SYS_TTBR0);
235 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR1_EL1),	SYS_TTBR1);
236 	if (ctxt_has_tcrx(ctxt)) {
237 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR2_EL1),	SYS_TCR2);
238 
239 		if (ctxt_has_s1pie(ctxt)) {
240 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIR_EL1),	SYS_PIR);
241 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIRE0_EL1),	SYS_PIRE0);
242 		}
243 
244 		if (ctxt_has_s1poe(ctxt))
245 			write_sysreg_el1(ctxt_sys_reg(ctxt, POR_EL1),	SYS_POR);
246 	}
247 	write_sysreg_el1(ctxt_sys_reg(ctxt, ESR_EL1),	SYS_ESR);
248 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR0_EL1),	SYS_AFSR0);
249 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR1_EL1),	SYS_AFSR1);
250 	write_sysreg_el1(ctxt_sys_reg(ctxt, FAR_EL1),	SYS_FAR);
251 	write_sysreg_el1(ctxt_sys_reg(ctxt, MAIR_EL1),	SYS_MAIR);
252 	write_sysreg_el1(ctxt_sys_reg(ctxt, VBAR_EL1),	SYS_VBAR);
253 	write_sysreg_el1(ctxt_sys_reg(ctxt, CONTEXTIDR_EL1), SYS_CONTEXTIDR);
254 	write_sysreg_el1(ctxt_sys_reg(ctxt, AMAIR_EL1),	SYS_AMAIR);
255 	write_sysreg_el1(ctxt_sys_reg(ctxt, CNTKCTL_EL1), SYS_CNTKCTL);
256 	write_sysreg(ctxt_sys_reg(ctxt, PAR_EL1),	par_el1);
257 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL1),	tpidr_el1);
258 
259 	if (ctxt_has_mte(ctxt)) {
260 		write_sysreg_el1(ctxt_sys_reg(ctxt, TFSR_EL1), SYS_TFSR);
261 		write_sysreg_s(ctxt_sys_reg(ctxt, TFSRE0_EL1), SYS_TFSRE0_EL1);
262 	}
263 
264 	if (!has_vhe() &&
265 	    cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) &&
266 	    ctxt->__hyp_running_vcpu) {
267 		/*
268 		 * Must only be done for host registers, hence the context
269 		 * test. Pairs with nVHE's __deactivate_traps().
270 		 */
271 		isb();
272 		/*
273 		 * At this stage, and thanks to the above isb(), S2 is
274 		 * deconfigured and disabled. We can now restore the host's
275 		 * S1 configuration: SCTLR, and only then TCR.
276 		 */
277 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
278 		isb();
279 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
280 	}
281 
282 	write_sysreg(ctxt_sys_reg(ctxt, SP_EL1),	sp_el1);
283 	write_sysreg_el1(ctxt_sys_reg(ctxt, ELR_EL1),	SYS_ELR);
284 	write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1),	SYS_SPSR);
285 
286 	if (ctxt_has_sctlr2(ctxt))
287 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR2_EL1), SYS_SCTLR2);
288 }
289 
290 /* Read the VCPU state's PSTATE, but translate (v)EL2 to EL1. */
to_hw_pstate(const struct kvm_cpu_context * ctxt)291 static inline u64 to_hw_pstate(const struct kvm_cpu_context *ctxt)
292 {
293 	u64 mode = ctxt->regs.pstate & (PSR_MODE_MASK | PSR_MODE32_BIT);
294 
295 	switch (mode) {
296 	case PSR_MODE_EL2t:
297 		mode = PSR_MODE_EL1t;
298 		break;
299 	case PSR_MODE_EL2h:
300 		mode = PSR_MODE_EL1h;
301 		break;
302 	}
303 
304 	return (ctxt->regs.pstate & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
305 }
306 
__sysreg_restore_el2_return_state(struct kvm_cpu_context * ctxt)307 static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt)
308 {
309 	u64 pstate = to_hw_pstate(ctxt);
310 	u64 mode = pstate & PSR_AA32_MODE_MASK;
311 	u64 vdisr;
312 
313 	/*
314 	 * Safety check to ensure we're setting the CPU up to enter the guest
315 	 * in a less privileged mode.
316 	 *
317 	 * If we are attempting a return to EL2 or higher in AArch64 state,
318 	 * program SPSR_EL2 with M=EL2h and the IL bit set which ensures that
319 	 * we'll take an illegal exception state exception immediately after
320 	 * the ERET to the guest.  Attempts to return to AArch32 Hyp will
321 	 * result in an illegal exception return because EL2's execution state
322 	 * is determined by SCR_EL3.RW.
323 	 */
324 	if (!(mode & PSR_MODE32_BIT) && mode >= PSR_MODE_EL2t)
325 		pstate = PSR_MODE_EL2h | PSR_IL_BIT;
326 
327 	write_sysreg_el2(ctxt->regs.pc,			SYS_ELR);
328 	write_sysreg_el2(pstate,			SYS_SPSR);
329 
330 	if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
331 		return;
332 
333 	if (!vserror_state_is_nested(ctxt_to_vcpu(ctxt)))
334 		vdisr = ctxt_sys_reg(ctxt, DISR_EL1);
335 	else if (ctxt_has_ras(ctxt))
336 		vdisr = ctxt_sys_reg(ctxt, VDISR_EL2);
337 	else
338 		vdisr = 0;
339 
340 	write_sysreg_s(vdisr, SYS_VDISR_EL2);
341 }
342 
__sysreg32_save_state(struct kvm_vcpu * vcpu)343 static inline void __sysreg32_save_state(struct kvm_vcpu *vcpu)
344 {
345 	if (!vcpu_el1_is_32bit(vcpu))
346 		return;
347 
348 	vcpu->arch.ctxt.spsr_abt = read_sysreg(spsr_abt);
349 	vcpu->arch.ctxt.spsr_und = read_sysreg(spsr_und);
350 	vcpu->arch.ctxt.spsr_irq = read_sysreg(spsr_irq);
351 	vcpu->arch.ctxt.spsr_fiq = read_sysreg(spsr_fiq);
352 
353 	__vcpu_assign_sys_reg(vcpu, DACR32_EL2, read_sysreg(dacr32_el2));
354 	__vcpu_assign_sys_reg(vcpu, IFSR32_EL2, read_sysreg(ifsr32_el2));
355 
356 	if (has_vhe() || kvm_debug_regs_in_use(vcpu))
357 		__vcpu_assign_sys_reg(vcpu, DBGVCR32_EL2, read_sysreg(dbgvcr32_el2));
358 }
359 
__sysreg32_restore_state(struct kvm_vcpu * vcpu)360 static inline void __sysreg32_restore_state(struct kvm_vcpu *vcpu)
361 {
362 	if (!vcpu_el1_is_32bit(vcpu))
363 		return;
364 
365 	write_sysreg(vcpu->arch.ctxt.spsr_abt, spsr_abt);
366 	write_sysreg(vcpu->arch.ctxt.spsr_und, spsr_und);
367 	write_sysreg(vcpu->arch.ctxt.spsr_irq, spsr_irq);
368 	write_sysreg(vcpu->arch.ctxt.spsr_fiq, spsr_fiq);
369 
370 	write_sysreg(__vcpu_sys_reg(vcpu, DACR32_EL2), dacr32_el2);
371 	write_sysreg(__vcpu_sys_reg(vcpu, IFSR32_EL2), ifsr32_el2);
372 
373 	if (has_vhe() || kvm_debug_regs_in_use(vcpu))
374 		write_sysreg(__vcpu_sys_reg(vcpu, DBGVCR32_EL2), dbgvcr32_el2);
375 }
376 
377 #endif /* __ARM64_KVM_HYP_SYSREG_SR_H__ */
378