1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright 2017 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
4 | */ |
5 | |
6 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
7 | |
8 | #include <linux/kvm_host.h> |
9 | |
10 | #include <asm/kvm_ppc.h> |
11 | #include <asm/kvm_book3s.h> |
12 | #include <asm/kvm_book3s_64.h> |
13 | #include <asm/reg.h> |
14 | #include <asm/ppc-opcode.h> |
15 | |
16 | static void emulate_tx_failure(struct kvm_vcpu *vcpu, u64 failure_cause) |
17 | { |
18 | u64 texasr, tfiar; |
19 | u64 msr = vcpu->arch.shregs.msr; |
20 | |
21 | tfiar = vcpu->arch.regs.nip & ~0x3ull; |
22 | texasr = (failure_cause << 56) | TEXASR_ABORT | TEXASR_FS | TEXASR_EXACT; |
23 | if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr)) |
24 | texasr |= TEXASR_SUSP; |
25 | if (msr & MSR_PR) { |
26 | texasr |= TEXASR_PR; |
27 | tfiar |= 1; |
28 | } |
29 | vcpu->arch.tfiar = tfiar; |
30 | /* Preserve ROT and TL fields of existing TEXASR */ |
31 | vcpu->arch.texasr = (vcpu->arch.texasr & 0x3ffffff) | texasr; |
32 | } |
33 | |
34 | /* |
35 | * This gets called on a softpatch interrupt on POWER9 DD2.2 processors. |
36 | * We expect to find a TM-related instruction to be emulated. The |
37 | * instruction image is in vcpu->arch.emul_inst. If the guest was in |
38 | * TM suspended or transactional state, the checkpointed state has been |
39 | * reclaimed and is in the vcpu struct. The CPU is in virtual mode in |
40 | * host context. |
41 | */ |
42 | int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) |
43 | { |
44 | u32 instr = vcpu->arch.emul_inst; |
45 | u64 msr = vcpu->arch.shregs.msr; |
46 | u64 newmsr, bescr; |
47 | int ra, rs; |
48 | |
49 | /* |
50 | * The TM softpatch interrupt sets NIP to the instruction following |
51 | * the faulting instruction, which is not executed. Rewind nip to the |
52 | * faulting instruction so it looks like a normal synchronous |
53 | * interrupt, then update nip in the places where the instruction is |
54 | * emulated. |
55 | */ |
56 | vcpu->arch.regs.nip -= 4; |
57 | |
58 | /* |
59 | * rfid, rfebb, and mtmsrd encode bit 31 = 0 since it's a reserved bit |
60 | * in these instructions, so masking bit 31 out doesn't change these |
61 | * instructions. For treclaim., tsr., and trechkpt. instructions if bit |
62 | * 31 = 0 then they are per ISA invalid forms, however P9 UM, in section |
63 | * 4.6.10 Book II Invalid Forms, informs specifically that ignoring bit |
64 | * 31 is an acceptable way to handle these invalid forms that have |
65 | * bit 31 = 0. Moreover, for emulation purposes both forms (w/ and wo/ |
66 | * bit 31 set) can generate a softpatch interrupt. Hence both forms |
67 | * are handled below for these instructions so they behave the same way. |
68 | */ |
69 | switch (instr & PO_XOP_OPCODE_MASK) { |
70 | case PPC_INST_RFID: |
71 | /* XXX do we need to check for PR=0 here? */ |
72 | newmsr = vcpu->arch.shregs.srr1; |
73 | /* should only get here for Sx -> T1 transition */ |
74 | WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) && |
75 | MSR_TM_TRANSACTIONAL(newmsr) && |
76 | (newmsr & MSR_TM))); |
77 | newmsr = sanitize_msr(newmsr); |
78 | vcpu->arch.shregs.msr = newmsr; |
79 | vcpu->arch.cfar = vcpu->arch.regs.nip; |
80 | vcpu->arch.regs.nip = vcpu->arch.shregs.srr0; |
81 | return RESUME_GUEST; |
82 | |
83 | case PPC_INST_RFEBB: |
84 | if ((msr & MSR_PR) && (vcpu->arch.vcore->pcr & PCR_ARCH_206)) { |
85 | /* generate an illegal instruction interrupt */ |
86 | kvmppc_core_queue_program(vcpu, SRR1_PROGILL); |
87 | return RESUME_GUEST; |
88 | } |
89 | /* check EBB facility is available */ |
90 | if (!(vcpu->arch.hfscr & HFSCR_EBB)) { |
91 | vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE; |
92 | vcpu->arch.hfscr |= (u64)FSCR_EBB_LG << 56; |
93 | vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL; |
94 | return -1; /* rerun host interrupt handler */ |
95 | } |
96 | if ((msr & MSR_PR) && !(vcpu->arch.fscr & FSCR_EBB)) { |
97 | /* generate a facility unavailable interrupt */ |
98 | vcpu->arch.fscr &= ~FSCR_INTR_CAUSE; |
99 | vcpu->arch.fscr |= (u64)FSCR_EBB_LG << 56; |
100 | kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_FAC_UNAVAIL); |
101 | return RESUME_GUEST; |
102 | } |
103 | bescr = vcpu->arch.bescr; |
104 | /* expect to see a S->T transition requested */ |
105 | WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) && |
106 | ((bescr >> 30) & 3) == 2)); |
107 | bescr &= ~BESCR_GE; |
108 | if (instr & (1 << 11)) |
109 | bescr |= BESCR_GE; |
110 | vcpu->arch.bescr = bescr; |
111 | msr = (msr & ~MSR_TS_MASK) | MSR_TS_T; |
112 | vcpu->arch.shregs.msr = msr; |
113 | vcpu->arch.cfar = vcpu->arch.regs.nip; |
114 | vcpu->arch.regs.nip = vcpu->arch.ebbrr; |
115 | return RESUME_GUEST; |
116 | |
117 | case PPC_INST_MTMSRD: |
118 | /* XXX do we need to check for PR=0 here? */ |
119 | rs = (instr >> 21) & 0x1f; |
120 | newmsr = kvmppc_get_gpr(vcpu, rs); |
121 | /* check this is a Sx -> T1 transition */ |
122 | WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) && |
123 | MSR_TM_TRANSACTIONAL(newmsr) && |
124 | (newmsr & MSR_TM))); |
125 | /* mtmsrd doesn't change LE */ |
126 | newmsr = (newmsr & ~MSR_LE) | (msr & MSR_LE); |
127 | newmsr = sanitize_msr(newmsr); |
128 | vcpu->arch.shregs.msr = newmsr; |
129 | vcpu->arch.regs.nip += 4; |
130 | return RESUME_GUEST; |
131 | |
132 | /* ignore bit 31, see comment above */ |
133 | case (PPC_INST_TSR & PO_XOP_OPCODE_MASK): |
134 | /* check for PR=1 and arch 2.06 bit set in PCR */ |
135 | if ((msr & MSR_PR) && (vcpu->arch.vcore->pcr & PCR_ARCH_206)) { |
136 | /* generate an illegal instruction interrupt */ |
137 | kvmppc_core_queue_program(vcpu, SRR1_PROGILL); |
138 | return RESUME_GUEST; |
139 | } |
140 | /* check for TM disabled in the HFSCR or MSR */ |
141 | if (!(vcpu->arch.hfscr & HFSCR_TM)) { |
142 | vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE; |
143 | vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56; |
144 | vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL; |
145 | return -1; /* rerun host interrupt handler */ |
146 | } |
147 | if (!(msr & MSR_TM)) { |
148 | /* generate a facility unavailable interrupt */ |
149 | vcpu->arch.fscr &= ~FSCR_INTR_CAUSE; |
150 | vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56; |
151 | kvmppc_book3s_queue_irqprio(vcpu, |
152 | BOOK3S_INTERRUPT_FAC_UNAVAIL); |
153 | return RESUME_GUEST; |
154 | } |
155 | /* Set CR0 to indicate previous transactional state */ |
156 | vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | |
157 | (((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29); |
158 | /* L=1 => tresume, L=0 => tsuspend */ |
159 | if (instr & (1 << 21)) { |
160 | if (MSR_TM_SUSPENDED(msr)) |
161 | msr = (msr & ~MSR_TS_MASK) | MSR_TS_T; |
162 | } else { |
163 | if (MSR_TM_TRANSACTIONAL(msr)) |
164 | msr = (msr & ~MSR_TS_MASK) | MSR_TS_S; |
165 | } |
166 | vcpu->arch.shregs.msr = msr; |
167 | vcpu->arch.regs.nip += 4; |
168 | return RESUME_GUEST; |
169 | |
170 | /* ignore bit 31, see comment above */ |
171 | case (PPC_INST_TRECLAIM & PO_XOP_OPCODE_MASK): |
172 | /* check for TM disabled in the HFSCR or MSR */ |
173 | if (!(vcpu->arch.hfscr & HFSCR_TM)) { |
174 | vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE; |
175 | vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56; |
176 | vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL; |
177 | return -1; /* rerun host interrupt handler */ |
178 | } |
179 | if (!(msr & MSR_TM)) { |
180 | /* generate a facility unavailable interrupt */ |
181 | vcpu->arch.fscr &= ~FSCR_INTR_CAUSE; |
182 | vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56; |
183 | kvmppc_book3s_queue_irqprio(vcpu, |
184 | BOOK3S_INTERRUPT_FAC_UNAVAIL); |
185 | return RESUME_GUEST; |
186 | } |
187 | /* If no transaction active, generate TM bad thing */ |
188 | if (!MSR_TM_ACTIVE(msr)) { |
189 | kvmppc_core_queue_program(vcpu, SRR1_PROGTM); |
190 | return RESUME_GUEST; |
191 | } |
192 | /* If failure was not previously recorded, recompute TEXASR */ |
193 | if (!(vcpu->arch.orig_texasr & TEXASR_FS)) { |
194 | ra = (instr >> 16) & 0x1f; |
195 | if (ra) |
196 | ra = kvmppc_get_gpr(vcpu, ra) & 0xff; |
197 | emulate_tx_failure(vcpu, failure_cause: ra); |
198 | } |
199 | |
200 | copy_from_checkpoint(vcpu); |
201 | |
202 | /* Set CR0 to indicate previous transactional state */ |
203 | vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | |
204 | (((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29); |
205 | vcpu->arch.shregs.msr &= ~MSR_TS_MASK; |
206 | vcpu->arch.regs.nip += 4; |
207 | return RESUME_GUEST; |
208 | |
209 | /* ignore bit 31, see comment above */ |
210 | case (PPC_INST_TRECHKPT & PO_XOP_OPCODE_MASK): |
211 | /* XXX do we need to check for PR=0 here? */ |
212 | /* check for TM disabled in the HFSCR or MSR */ |
213 | if (!(vcpu->arch.hfscr & HFSCR_TM)) { |
214 | vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE; |
215 | vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56; |
216 | vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL; |
217 | return -1; /* rerun host interrupt handler */ |
218 | } |
219 | if (!(msr & MSR_TM)) { |
220 | /* generate a facility unavailable interrupt */ |
221 | vcpu->arch.fscr &= ~FSCR_INTR_CAUSE; |
222 | vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56; |
223 | kvmppc_book3s_queue_irqprio(vcpu, |
224 | BOOK3S_INTERRUPT_FAC_UNAVAIL); |
225 | return RESUME_GUEST; |
226 | } |
227 | /* If transaction active or TEXASR[FS] = 0, bad thing */ |
228 | if (MSR_TM_ACTIVE(msr) || !(vcpu->arch.texasr & TEXASR_FS)) { |
229 | kvmppc_core_queue_program(vcpu, SRR1_PROGTM); |
230 | return RESUME_GUEST; |
231 | } |
232 | |
233 | copy_to_checkpoint(vcpu); |
234 | |
235 | /* Set CR0 to indicate previous transactional state */ |
236 | vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | |
237 | (((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29); |
238 | vcpu->arch.shregs.msr = msr | MSR_TS_S; |
239 | vcpu->arch.regs.nip += 4; |
240 | return RESUME_GUEST; |
241 | } |
242 | |
243 | /* What should we do here? We didn't recognize the instruction */ |
244 | kvmppc_core_queue_program(vcpu, SRR1_PROGILL); |
245 | pr_warn_ratelimited("Unrecognized TM-related instruction %#x for emulation" , instr); |
246 | |
247 | return RESUME_GUEST; |
248 | } |
249 | |