kvm_emul.S (8167B)
1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * 4 * Copyright SUSE Linux Products GmbH 2010 5 * Copyright 2010-2011 Freescale Semiconductor, Inc. 6 * 7 * Authors: Alexander Graf <agraf@suse.de> 8 */ 9 10#include <asm/ppc_asm.h> 11#include <asm/kvm_asm.h> 12#include <asm/reg.h> 13#include <asm/page.h> 14#include <asm/asm-offsets.h> 15#include <asm/asm-compat.h> 16 17#define KVM_MAGIC_PAGE (-4096) 18 19#ifdef CONFIG_64BIT 20#define LL64(reg, offs, reg2) ld reg, (offs)(reg2) 21#define STL64(reg, offs, reg2) std reg, (offs)(reg2) 22#else 23#define LL64(reg, offs, reg2) lwz reg, (offs + 4)(reg2) 24#define STL64(reg, offs, reg2) stw reg, (offs + 4)(reg2) 25#endif 26 27#define SCRATCH_SAVE \ 28 /* Enable critical section. We are critical if \ 29 shared->critical == r1 */ \ 30 STL64(r1, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0); \ 31 \ 32 /* Save state */ \ 33 PPC_STL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \ 34 PPC_STL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \ 35 mfcr r31; \ 36 stw r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0); 37 38#define SCRATCH_RESTORE \ 39 /* Restore state */ \ 40 PPC_LL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \ 41 lwz r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0); \ 42 mtcr r30; \ 43 PPC_LL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \ 44 \ 45 /* Disable critical section. We are critical if \ 46 shared->critical == r1 and r2 is always != r1 */ \ 47 STL64(r2, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0); 48 49.global kvm_template_start 50kvm_template_start: 51 52.global kvm_emulate_mtmsrd 53kvm_emulate_mtmsrd: 54 55 SCRATCH_SAVE 56 57 /* Put MSR & ~(MSR_EE|MSR_RI) in r31 */ 58 LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 59 lis r30, (~(MSR_EE | MSR_RI))@h 60 ori r30, r30, (~(MSR_EE | MSR_RI))@l 61 and r31, r31, r30 62 63 /* OR the register's (MSR_EE|MSR_RI) on MSR */ 64kvm_emulate_mtmsrd_reg: 65 ori r30, r0, 0 66 andi. r30, r30, (MSR_EE|MSR_RI) 67 or r31, r31, r30 68 69 /* Put MSR back into magic page */ 70 STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 71 72 /* Check if we have to fetch an interrupt */ 73 lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0) 74 cmpwi r31, 0 75 beq+ no_check 76 77 /* Check if we may trigger an interrupt */ 78 andi. r30, r30, MSR_EE 79 beq no_check 80 81 SCRATCH_RESTORE 82 83 /* Nag hypervisor */ 84kvm_emulate_mtmsrd_orig_ins: 85 tlbsync 86 87 b kvm_emulate_mtmsrd_branch 88 89no_check: 90 91 SCRATCH_RESTORE 92 93 /* Go back to caller */ 94kvm_emulate_mtmsrd_branch: 95 b . 96kvm_emulate_mtmsrd_end: 97 98.global kvm_emulate_mtmsrd_branch_offs 99kvm_emulate_mtmsrd_branch_offs: 100 .long (kvm_emulate_mtmsrd_branch - kvm_emulate_mtmsrd) / 4 101 102.global kvm_emulate_mtmsrd_reg_offs 103kvm_emulate_mtmsrd_reg_offs: 104 .long (kvm_emulate_mtmsrd_reg - kvm_emulate_mtmsrd) / 4 105 106.global kvm_emulate_mtmsrd_orig_ins_offs 107kvm_emulate_mtmsrd_orig_ins_offs: 108 .long (kvm_emulate_mtmsrd_orig_ins - kvm_emulate_mtmsrd) / 4 109 110.global kvm_emulate_mtmsrd_len 111kvm_emulate_mtmsrd_len: 112 .long (kvm_emulate_mtmsrd_end - kvm_emulate_mtmsrd) / 4 113 114 115#define MSR_SAFE_BITS (MSR_EE | MSR_RI) 116#define MSR_CRITICAL_BITS ~MSR_SAFE_BITS 117 118.global kvm_emulate_mtmsr 119kvm_emulate_mtmsr: 120 121 SCRATCH_SAVE 122 123 /* Fetch old MSR in r31 */ 124 LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 125 126 /* Find the changed bits between old and new MSR */ 127kvm_emulate_mtmsr_reg1: 128 ori r30, r0, 0 129 xor r31, r30, r31 130 131 /* Check if we need to really do mtmsr */ 132 LOAD_REG_IMMEDIATE(r30, MSR_CRITICAL_BITS) 133 and. r31, r31, r30 134 135 /* No critical bits changed? Maybe we can stay in the guest. */ 136 beq maybe_stay_in_guest 137 138do_mtmsr: 139 140 SCRATCH_RESTORE 141 142 /* Just fire off the mtmsr if it's critical */ 143kvm_emulate_mtmsr_orig_ins: 144 mtmsr r0 145 146 b kvm_emulate_mtmsr_branch 147 148maybe_stay_in_guest: 149 150 /* Get the target register in r30 */ 151kvm_emulate_mtmsr_reg2: 152 ori r30, r0, 0 153 154 /* Put MSR into magic page because we don't call mtmsr */ 155 STL64(r30, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 156 157 /* Check if we have to fetch an interrupt */ 158 lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0) 159 cmpwi r31, 0 160 beq+ no_mtmsr 161 162 /* Check if we may trigger an interrupt */ 163 andi. r31, r30, MSR_EE 164 bne do_mtmsr 165 166no_mtmsr: 167 168 SCRATCH_RESTORE 169 170 /* Go back to caller */ 171kvm_emulate_mtmsr_branch: 172 b . 173kvm_emulate_mtmsr_end: 174 175.global kvm_emulate_mtmsr_branch_offs 176kvm_emulate_mtmsr_branch_offs: 177 .long (kvm_emulate_mtmsr_branch - kvm_emulate_mtmsr) / 4 178 179.global kvm_emulate_mtmsr_reg1_offs 180kvm_emulate_mtmsr_reg1_offs: 181 .long (kvm_emulate_mtmsr_reg1 - kvm_emulate_mtmsr) / 4 182 183.global kvm_emulate_mtmsr_reg2_offs 184kvm_emulate_mtmsr_reg2_offs: 185 .long (kvm_emulate_mtmsr_reg2 - kvm_emulate_mtmsr) / 4 186 187.global kvm_emulate_mtmsr_orig_ins_offs 188kvm_emulate_mtmsr_orig_ins_offs: 189 .long (kvm_emulate_mtmsr_orig_ins - kvm_emulate_mtmsr) / 4 190 191.global kvm_emulate_mtmsr_len 192kvm_emulate_mtmsr_len: 193 .long (kvm_emulate_mtmsr_end - kvm_emulate_mtmsr) / 4 194 195#ifdef CONFIG_BOOKE 196 197/* also used for wrteei 1 */ 198.global kvm_emulate_wrtee 199kvm_emulate_wrtee: 200 201 SCRATCH_SAVE 202 203 /* Fetch old MSR in r31 */ 204 LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 205 206 /* Insert new MSR[EE] */ 207kvm_emulate_wrtee_reg: 208 ori r30, r0, 0 209 rlwimi r31, r30, 0, MSR_EE 210 211 /* 212 * If MSR[EE] is now set, check for a pending interrupt. 213 * We could skip this if MSR[EE] was already on, but that 214 * should be rare, so don't bother. 215 */ 216 andi. r30, r30, MSR_EE 217 218 /* Put MSR into magic page because we don't call wrtee */ 219 STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 220 221 beq no_wrtee 222 223 /* Check if we have to fetch an interrupt */ 224 lwz r30, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0) 225 cmpwi r30, 0 226 bne do_wrtee 227 228no_wrtee: 229 SCRATCH_RESTORE 230 231 /* Go back to caller */ 232kvm_emulate_wrtee_branch: 233 b . 234 235do_wrtee: 236 SCRATCH_RESTORE 237 238 /* Just fire off the wrtee if it's critical */ 239kvm_emulate_wrtee_orig_ins: 240 wrtee r0 241 242 b kvm_emulate_wrtee_branch 243 244kvm_emulate_wrtee_end: 245 246.global kvm_emulate_wrtee_branch_offs 247kvm_emulate_wrtee_branch_offs: 248 .long (kvm_emulate_wrtee_branch - kvm_emulate_wrtee) / 4 249 250.global kvm_emulate_wrtee_reg_offs 251kvm_emulate_wrtee_reg_offs: 252 .long (kvm_emulate_wrtee_reg - kvm_emulate_wrtee) / 4 253 254.global kvm_emulate_wrtee_orig_ins_offs 255kvm_emulate_wrtee_orig_ins_offs: 256 .long (kvm_emulate_wrtee_orig_ins - kvm_emulate_wrtee) / 4 257 258.global kvm_emulate_wrtee_len 259kvm_emulate_wrtee_len: 260 .long (kvm_emulate_wrtee_end - kvm_emulate_wrtee) / 4 261 262.global kvm_emulate_wrteei_0 263kvm_emulate_wrteei_0: 264 SCRATCH_SAVE 265 266 /* Fetch old MSR in r31 */ 267 LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 268 269 /* Remove MSR_EE from old MSR */ 270 rlwinm r31, r31, 0, ~MSR_EE 271 272 /* Write new MSR value back */ 273 STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 274 275 SCRATCH_RESTORE 276 277 /* Go back to caller */ 278kvm_emulate_wrteei_0_branch: 279 b . 280kvm_emulate_wrteei_0_end: 281 282.global kvm_emulate_wrteei_0_branch_offs 283kvm_emulate_wrteei_0_branch_offs: 284 .long (kvm_emulate_wrteei_0_branch - kvm_emulate_wrteei_0) / 4 285 286.global kvm_emulate_wrteei_0_len 287kvm_emulate_wrteei_0_len: 288 .long (kvm_emulate_wrteei_0_end - kvm_emulate_wrteei_0) / 4 289 290#endif /* CONFIG_BOOKE */ 291 292#ifdef CONFIG_PPC_BOOK3S_32 293 294.global kvm_emulate_mtsrin 295kvm_emulate_mtsrin: 296 297 SCRATCH_SAVE 298 299 LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) 300 andi. r31, r31, MSR_DR | MSR_IR 301 beq kvm_emulate_mtsrin_reg1 302 303 SCRATCH_RESTORE 304 305kvm_emulate_mtsrin_orig_ins: 306 nop 307 b kvm_emulate_mtsrin_branch 308 309kvm_emulate_mtsrin_reg1: 310 /* rX >> 26 */ 311 rlwinm r30,r0,6,26,29 312 313kvm_emulate_mtsrin_reg2: 314 stw r0, (KVM_MAGIC_PAGE + KVM_MAGIC_SR)(r30) 315 316 SCRATCH_RESTORE 317 318 /* Go back to caller */ 319kvm_emulate_mtsrin_branch: 320 b . 321kvm_emulate_mtsrin_end: 322 323.global kvm_emulate_mtsrin_branch_offs 324kvm_emulate_mtsrin_branch_offs: 325 .long (kvm_emulate_mtsrin_branch - kvm_emulate_mtsrin) / 4 326 327.global kvm_emulate_mtsrin_reg1_offs 328kvm_emulate_mtsrin_reg1_offs: 329 .long (kvm_emulate_mtsrin_reg1 - kvm_emulate_mtsrin) / 4 330 331.global kvm_emulate_mtsrin_reg2_offs 332kvm_emulate_mtsrin_reg2_offs: 333 .long (kvm_emulate_mtsrin_reg2 - kvm_emulate_mtsrin) / 4 334 335.global kvm_emulate_mtsrin_orig_ins_offs 336kvm_emulate_mtsrin_orig_ins_offs: 337 .long (kvm_emulate_mtsrin_orig_ins - kvm_emulate_mtsrin) / 4 338 339.global kvm_emulate_mtsrin_len 340kvm_emulate_mtsrin_len: 341 .long (kvm_emulate_mtsrin_end - kvm_emulate_mtsrin) / 4 342 343#endif /* CONFIG_PPC_BOOK3S_32 */ 344 345 .balign 4 346 .global kvm_tmp 347kvm_tmp: 348 .space (64 * 1024) 349 350.global kvm_tmp_end 351kvm_tmp_end: 352 353.global kvm_template_end 354kvm_template_end: