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 
__sysreg_save_common_state(struct kvm_cpu_context * ctxt)21 static inline void __sysreg_save_common_state(struct kvm_cpu_context *ctxt)
22 {
23 	ctxt_sys_reg(ctxt, MDSCR_EL1)	= read_sysreg(mdscr_el1);
24 
25 	// POR_EL0 can affect uaccess, so must be saved/restored early.
26 	if (ctxt_has_s1poe(ctxt))
27 		ctxt_sys_reg(ctxt, POR_EL0)	= read_sysreg_s(SYS_POR_EL0);
28 }
29 
__sysreg_save_user_state(struct kvm_cpu_context * ctxt)30 static inline void __sysreg_save_user_state(struct kvm_cpu_context *ctxt)
31 {
32 	ctxt_sys_reg(ctxt, TPIDR_EL0)	= read_sysreg(tpidr_el0);
33 	ctxt_sys_reg(ctxt, TPIDRRO_EL0)	= read_sysreg(tpidrro_el0);
34 }
35 
ctxt_to_vcpu(struct kvm_cpu_context * ctxt)36 static inline struct kvm_vcpu *ctxt_to_vcpu(struct kvm_cpu_context *ctxt)
37 {
38 	struct kvm_vcpu *vcpu = ctxt->__hyp_running_vcpu;
39 
40 	if (!vcpu)
41 		vcpu = container_of(ctxt, struct kvm_vcpu, arch.ctxt);
42 
43 	return vcpu;
44 }
45 
ctxt_has_mte(struct kvm_cpu_context * ctxt)46 static inline bool ctxt_has_mte(struct kvm_cpu_context *ctxt)
47 {
48 	struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
49 
50 	return kvm_has_mte(kern_hyp_va(vcpu->kvm));
51 }
52 
ctxt_has_s1pie(struct kvm_cpu_context * ctxt)53 static inline bool ctxt_has_s1pie(struct kvm_cpu_context *ctxt)
54 {
55 	struct kvm_vcpu *vcpu;
56 
57 	if (!cpus_have_final_cap(ARM64_HAS_S1PIE))
58 		return false;
59 
60 	vcpu = ctxt_to_vcpu(ctxt);
61 	return kvm_has_feat(kern_hyp_va(vcpu->kvm), ID_AA64MMFR3_EL1, S1PIE, IMP);
62 }
63 
ctxt_has_tcrx(struct kvm_cpu_context * ctxt)64 static inline bool ctxt_has_tcrx(struct kvm_cpu_context *ctxt)
65 {
66 	struct kvm_vcpu *vcpu;
67 
68 	if (!cpus_have_final_cap(ARM64_HAS_TCR2))
69 		return false;
70 
71 	vcpu = ctxt_to_vcpu(ctxt);
72 	return kvm_has_feat(kern_hyp_va(vcpu->kvm), ID_AA64MMFR3_EL1, TCRX, IMP);
73 }
74 
ctxt_has_s1poe(struct kvm_cpu_context * ctxt)75 static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt)
76 {
77 	struct kvm_vcpu *vcpu;
78 
79 	if (!system_supports_poe())
80 		return false;
81 
82 	vcpu = ctxt_to_vcpu(ctxt);
83 	return kvm_has_feat(kern_hyp_va(vcpu->kvm), ID_AA64MMFR3_EL1, S1POE, IMP);
84 }
85 
__sysreg_save_el1_state(struct kvm_cpu_context * ctxt)86 static inline void __sysreg_save_el1_state(struct kvm_cpu_context *ctxt)
87 {
88 	ctxt_sys_reg(ctxt, SCTLR_EL1)	= read_sysreg_el1(SYS_SCTLR);
89 	ctxt_sys_reg(ctxt, CPACR_EL1)	= read_sysreg_el1(SYS_CPACR);
90 	ctxt_sys_reg(ctxt, TTBR0_EL1)	= read_sysreg_el1(SYS_TTBR0);
91 	ctxt_sys_reg(ctxt, TTBR1_EL1)	= read_sysreg_el1(SYS_TTBR1);
92 	ctxt_sys_reg(ctxt, TCR_EL1)	= read_sysreg_el1(SYS_TCR);
93 	if (ctxt_has_tcrx(ctxt)) {
94 		ctxt_sys_reg(ctxt, TCR2_EL1)	= read_sysreg_el1(SYS_TCR2);
95 
96 		if (ctxt_has_s1pie(ctxt)) {
97 			ctxt_sys_reg(ctxt, PIR_EL1)	= read_sysreg_el1(SYS_PIR);
98 			ctxt_sys_reg(ctxt, PIRE0_EL1)	= read_sysreg_el1(SYS_PIRE0);
99 		}
100 
101 		if (ctxt_has_s1poe(ctxt))
102 			ctxt_sys_reg(ctxt, POR_EL1)	= read_sysreg_el1(SYS_POR);
103 	}
104 	ctxt_sys_reg(ctxt, ESR_EL1)	= read_sysreg_el1(SYS_ESR);
105 	ctxt_sys_reg(ctxt, AFSR0_EL1)	= read_sysreg_el1(SYS_AFSR0);
106 	ctxt_sys_reg(ctxt, AFSR1_EL1)	= read_sysreg_el1(SYS_AFSR1);
107 	ctxt_sys_reg(ctxt, FAR_EL1)	= read_sysreg_el1(SYS_FAR);
108 	ctxt_sys_reg(ctxt, MAIR_EL1)	= read_sysreg_el1(SYS_MAIR);
109 	ctxt_sys_reg(ctxt, VBAR_EL1)	= read_sysreg_el1(SYS_VBAR);
110 	ctxt_sys_reg(ctxt, CONTEXTIDR_EL1) = read_sysreg_el1(SYS_CONTEXTIDR);
111 	ctxt_sys_reg(ctxt, AMAIR_EL1)	= read_sysreg_el1(SYS_AMAIR);
112 	ctxt_sys_reg(ctxt, CNTKCTL_EL1)	= read_sysreg_el1(SYS_CNTKCTL);
113 	ctxt_sys_reg(ctxt, PAR_EL1)	= read_sysreg_par();
114 	ctxt_sys_reg(ctxt, TPIDR_EL1)	= read_sysreg(tpidr_el1);
115 
116 	if (ctxt_has_mte(ctxt)) {
117 		ctxt_sys_reg(ctxt, TFSR_EL1) = read_sysreg_el1(SYS_TFSR);
118 		ctxt_sys_reg(ctxt, TFSRE0_EL1) = read_sysreg_s(SYS_TFSRE0_EL1);
119 	}
120 
121 	ctxt_sys_reg(ctxt, SP_EL1)	= read_sysreg(sp_el1);
122 	ctxt_sys_reg(ctxt, ELR_EL1)	= read_sysreg_el1(SYS_ELR);
123 	ctxt_sys_reg(ctxt, SPSR_EL1)	= read_sysreg_el1(SYS_SPSR);
124 }
125 
__sysreg_save_el2_return_state(struct kvm_cpu_context * ctxt)126 static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt)
127 {
128 	ctxt->regs.pc			= read_sysreg_el2(SYS_ELR);
129 	/*
130 	 * Guest PSTATE gets saved at guest fixup time in all
131 	 * cases. We still need to handle the nVHE host side here.
132 	 */
133 	if (!has_vhe() && ctxt->__hyp_running_vcpu)
134 		ctxt->regs.pstate	= read_sysreg_el2(SYS_SPSR);
135 
136 	if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
137 		ctxt_sys_reg(ctxt, DISR_EL1) = read_sysreg_s(SYS_VDISR_EL2);
138 }
139 
__sysreg_restore_common_state(struct kvm_cpu_context * ctxt)140 static inline void __sysreg_restore_common_state(struct kvm_cpu_context *ctxt)
141 {
142 	write_sysreg(ctxt_sys_reg(ctxt, MDSCR_EL1),  mdscr_el1);
143 
144 	// POR_EL0 can affect uaccess, so must be saved/restored early.
145 	if (ctxt_has_s1poe(ctxt))
146 		write_sysreg_s(ctxt_sys_reg(ctxt, POR_EL0),	SYS_POR_EL0);
147 }
148 
__sysreg_restore_user_state(struct kvm_cpu_context * ctxt)149 static inline void __sysreg_restore_user_state(struct kvm_cpu_context *ctxt)
150 {
151 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL0),	tpidr_el0);
152 	write_sysreg(ctxt_sys_reg(ctxt, TPIDRRO_EL0),	tpidrro_el0);
153 }
154 
__sysreg_restore_el1_state(struct kvm_cpu_context * ctxt)155 static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
156 {
157 	write_sysreg(ctxt_sys_reg(ctxt, MPIDR_EL1),	vmpidr_el2);
158 
159 	if (has_vhe() ||
160 	    !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
161 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
162 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
163 	} else	if (!ctxt->__hyp_running_vcpu) {
164 		/*
165 		 * Must only be done for guest registers, hence the context
166 		 * test. We're coming from the host, so SCTLR.M is already
167 		 * set. Pairs with nVHE's __activate_traps().
168 		 */
169 		write_sysreg_el1((ctxt_sys_reg(ctxt, TCR_EL1) |
170 				  TCR_EPD1_MASK | TCR_EPD0_MASK),
171 				 SYS_TCR);
172 		isb();
173 	}
174 
175 	write_sysreg_el1(ctxt_sys_reg(ctxt, CPACR_EL1),	SYS_CPACR);
176 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR0_EL1),	SYS_TTBR0);
177 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR1_EL1),	SYS_TTBR1);
178 	if (ctxt_has_tcrx(ctxt)) {
179 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR2_EL1),	SYS_TCR2);
180 
181 		if (ctxt_has_s1pie(ctxt)) {
182 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIR_EL1),	SYS_PIR);
183 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIRE0_EL1),	SYS_PIRE0);
184 		}
185 
186 		if (ctxt_has_s1poe(ctxt))
187 			write_sysreg_el1(ctxt_sys_reg(ctxt, POR_EL1),	SYS_POR);
188 	}
189 	write_sysreg_el1(ctxt_sys_reg(ctxt, ESR_EL1),	SYS_ESR);
190 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR0_EL1),	SYS_AFSR0);
191 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR1_EL1),	SYS_AFSR1);
192 	write_sysreg_el1(ctxt_sys_reg(ctxt, FAR_EL1),	SYS_FAR);
193 	write_sysreg_el1(ctxt_sys_reg(ctxt, MAIR_EL1),	SYS_MAIR);
194 	write_sysreg_el1(ctxt_sys_reg(ctxt, VBAR_EL1),	SYS_VBAR);
195 	write_sysreg_el1(ctxt_sys_reg(ctxt, CONTEXTIDR_EL1), SYS_CONTEXTIDR);
196 	write_sysreg_el1(ctxt_sys_reg(ctxt, AMAIR_EL1),	SYS_AMAIR);
197 	write_sysreg_el1(ctxt_sys_reg(ctxt, CNTKCTL_EL1), SYS_CNTKCTL);
198 	write_sysreg(ctxt_sys_reg(ctxt, PAR_EL1),	par_el1);
199 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL1),	tpidr_el1);
200 
201 	if (ctxt_has_mte(ctxt)) {
202 		write_sysreg_el1(ctxt_sys_reg(ctxt, TFSR_EL1), SYS_TFSR);
203 		write_sysreg_s(ctxt_sys_reg(ctxt, TFSRE0_EL1), SYS_TFSRE0_EL1);
204 	}
205 
206 	if (!has_vhe() &&
207 	    cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) &&
208 	    ctxt->__hyp_running_vcpu) {
209 		/*
210 		 * Must only be done for host registers, hence the context
211 		 * test. Pairs with nVHE's __deactivate_traps().
212 		 */
213 		isb();
214 		/*
215 		 * At this stage, and thanks to the above isb(), S2 is
216 		 * deconfigured and disabled. We can now restore the host's
217 		 * S1 configuration: SCTLR, and only then TCR.
218 		 */
219 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
220 		isb();
221 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
222 	}
223 
224 	write_sysreg(ctxt_sys_reg(ctxt, SP_EL1),	sp_el1);
225 	write_sysreg_el1(ctxt_sys_reg(ctxt, ELR_EL1),	SYS_ELR);
226 	write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1),	SYS_SPSR);
227 }
228 
229 /* Read the VCPU state's PSTATE, but translate (v)EL2 to EL1. */
to_hw_pstate(const struct kvm_cpu_context * ctxt)230 static inline u64 to_hw_pstate(const struct kvm_cpu_context *ctxt)
231 {
232 	u64 mode = ctxt->regs.pstate & (PSR_MODE_MASK | PSR_MODE32_BIT);
233 
234 	switch (mode) {
235 	case PSR_MODE_EL2t:
236 		mode = PSR_MODE_EL1t;
237 		break;
238 	case PSR_MODE_EL2h:
239 		mode = PSR_MODE_EL1h;
240 		break;
241 	}
242 
243 	return (ctxt->regs.pstate & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
244 }
245 
__sysreg_restore_el2_return_state(struct kvm_cpu_context * ctxt)246 static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt)
247 {
248 	u64 pstate = to_hw_pstate(ctxt);
249 	u64 mode = pstate & PSR_AA32_MODE_MASK;
250 
251 	/*
252 	 * Safety check to ensure we're setting the CPU up to enter the guest
253 	 * in a less privileged mode.
254 	 *
255 	 * If we are attempting a return to EL2 or higher in AArch64 state,
256 	 * program SPSR_EL2 with M=EL2h and the IL bit set which ensures that
257 	 * we'll take an illegal exception state exception immediately after
258 	 * the ERET to the guest.  Attempts to return to AArch32 Hyp will
259 	 * result in an illegal exception return because EL2's execution state
260 	 * is determined by SCR_EL3.RW.
261 	 */
262 	if (!(mode & PSR_MODE32_BIT) && mode >= PSR_MODE_EL2t)
263 		pstate = PSR_MODE_EL2h | PSR_IL_BIT;
264 
265 	write_sysreg_el2(ctxt->regs.pc,			SYS_ELR);
266 	write_sysreg_el2(pstate,			SYS_SPSR);
267 
268 	if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
269 		write_sysreg_s(ctxt_sys_reg(ctxt, DISR_EL1), SYS_VDISR_EL2);
270 }
271 
__sysreg32_save_state(struct kvm_vcpu * vcpu)272 static inline void __sysreg32_save_state(struct kvm_vcpu *vcpu)
273 {
274 	if (!vcpu_el1_is_32bit(vcpu))
275 		return;
276 
277 	vcpu->arch.ctxt.spsr_abt = read_sysreg(spsr_abt);
278 	vcpu->arch.ctxt.spsr_und = read_sysreg(spsr_und);
279 	vcpu->arch.ctxt.spsr_irq = read_sysreg(spsr_irq);
280 	vcpu->arch.ctxt.spsr_fiq = read_sysreg(spsr_fiq);
281 
282 	__vcpu_sys_reg(vcpu, DACR32_EL2) = read_sysreg(dacr32_el2);
283 	__vcpu_sys_reg(vcpu, IFSR32_EL2) = read_sysreg(ifsr32_el2);
284 
285 	if (has_vhe() || vcpu_get_flag(vcpu, DEBUG_DIRTY))
286 		__vcpu_sys_reg(vcpu, DBGVCR32_EL2) = read_sysreg(dbgvcr32_el2);
287 }
288 
__sysreg32_restore_state(struct kvm_vcpu * vcpu)289 static inline void __sysreg32_restore_state(struct kvm_vcpu *vcpu)
290 {
291 	if (!vcpu_el1_is_32bit(vcpu))
292 		return;
293 
294 	write_sysreg(vcpu->arch.ctxt.spsr_abt, spsr_abt);
295 	write_sysreg(vcpu->arch.ctxt.spsr_und, spsr_und);
296 	write_sysreg(vcpu->arch.ctxt.spsr_irq, spsr_irq);
297 	write_sysreg(vcpu->arch.ctxt.spsr_fiq, spsr_fiq);
298 
299 	write_sysreg(__vcpu_sys_reg(vcpu, DACR32_EL2), dacr32_el2);
300 	write_sysreg(__vcpu_sys_reg(vcpu, IFSR32_EL2), ifsr32_el2);
301 
302 	if (has_vhe() || vcpu_get_flag(vcpu, DEBUG_DIRTY))
303 		write_sysreg(__vcpu_sys_reg(vcpu, DBGVCR32_EL2), dbgvcr32_el2);
304 }
305 
306 #endif /* __ARM64_KVM_HYP_SYSREG_SR_H__ */
307