| 1 | # |
| 2 | # Local APIC acceleration for Windows XP and related guests |
| 3 | # |
| 4 | # Copyright 2011 Red Hat, Inc. and/or its affiliates |
| 5 | # |
| 6 | # Author: Avi Kivity <avi@redhat.com> |
| 7 | # |
| 8 | # This work is licensed under the terms of the GNU GPL, version 2, or (at your |
| 9 | # option) any later version. See the COPYING file in the top-level directory. |
| 10 | # |
| 11 | |
| 12 | #include "optionrom.h" |
| 13 | |
| 14 | OPTION_ROM_START |
| 15 | |
| 16 | # clear vapic area: firmware load using rep insb may cause |
| 17 | # stale tpr/isr/irr data to corrupt the vapic area. |
| 18 | push %es |
| 19 | push %cs |
| 20 | pop %es |
| 21 | xor %ax, %ax |
| 22 | mov $vapic_size/2, %cx |
| 23 | lea vapic, %di |
| 24 | cld |
| 25 | rep stosw |
| 26 | pop %es |
| 27 | |
| 28 | # announce presence to the hypervisor |
| 29 | mov $vapic_base, %ax |
| 30 | out %ax, $0x7e |
| 31 | |
| 32 | lret |
| 33 | |
| 34 | .code32 |
| 35 | vapic_size = 2*4096 |
| 36 | |
| 37 | .macro fixup delta=-4 |
| 38 | 777: |
| 39 | .text 1 |
| 40 | .long 777b + \delta - vapic_base |
| 41 | .text 0 |
| 42 | .endm |
| 43 | |
| 44 | .macro reenable_vtpr |
| 45 | out %al, $0x7e |
| 46 | .endm |
| 47 | |
| 48 | .text 1 |
| 49 | fixup_start = . |
| 50 | .text 0 |
| 51 | |
| 52 | .align 16 |
| 53 | |
| 54 | vapic_base: |
| 55 | .ascii "kvm aPiC" |
| 56 | |
| 57 | /* relocation data */ |
| 58 | .long vapic_base ; fixup |
| 59 | .long fixup_start ; fixup |
| 60 | .long fixup_end ; fixup |
| 61 | |
| 62 | .long vapic ; fixup |
| 63 | .long vapic_size |
| 64 | vcpu_shift: |
| 65 | .long 0 |
| 66 | real_tpr: |
| 67 | .long 0 |
| 68 | .long up_set_tpr ; fixup |
| 69 | .long up_set_tpr_eax ; fixup |
| 70 | .long up_get_tpr_eax ; fixup |
| 71 | .long up_get_tpr_ecx ; fixup |
| 72 | .long up_get_tpr_edx ; fixup |
| 73 | .long up_get_tpr_ebx ; fixup |
| 74 | .long 0 /* esp. won't work. */ |
| 75 | .long up_get_tpr_ebp ; fixup |
| 76 | .long up_get_tpr_esi ; fixup |
| 77 | .long up_get_tpr_edi ; fixup |
| 78 | .long up_get_tpr_stack ; fixup |
| 79 | .long mp_set_tpr ; fixup |
| 80 | .long mp_set_tpr_eax ; fixup |
| 81 | .long mp_get_tpr_eax ; fixup |
| 82 | .long mp_get_tpr_ecx ; fixup |
| 83 | .long mp_get_tpr_edx ; fixup |
| 84 | .long mp_get_tpr_ebx ; fixup |
| 85 | .long 0 /* esp. won't work. */ |
| 86 | .long mp_get_tpr_ebp ; fixup |
| 87 | .long mp_get_tpr_esi ; fixup |
| 88 | .long mp_get_tpr_edi ; fixup |
| 89 | .long mp_get_tpr_stack ; fixup |
| 90 | |
| 91 | .macro kvm_hypercall |
| 92 | .byte 0x0f, 0x01, 0xc1 |
| 93 | .endm |
| 94 | |
| 95 | kvm_hypercall_vapic_poll_irq = 1 |
| 96 | |
| 97 | pcr_cpu = 0x51 |
| 98 | |
| 99 | .align 64 |
| 100 | |
| 101 | mp_get_tpr_eax: |
| 102 | pushf |
| 103 | cli |
| 104 | reenable_vtpr |
| 105 | push %ecx |
| 106 | |
| 107 | fs/movzbl pcr_cpu, %eax |
| 108 | |
| 109 | mov vcpu_shift, %ecx ; fixup |
| 110 | shl %cl, %eax |
| 111 | testb $1, vapic+4(%eax) ; fixup delta=-5 |
| 112 | jz mp_get_tpr_bad |
| 113 | movzbl vapic(%eax), %eax ; fixup |
| 114 | |
| 115 | mp_get_tpr_out: |
| 116 | pop %ecx |
| 117 | popf |
| 118 | ret |
| 119 | |
| 120 | mp_get_tpr_bad: |
| 121 | mov real_tpr, %eax ; fixup |
| 122 | mov (%eax), %eax |
| 123 | jmp mp_get_tpr_out |
| 124 | |
| 125 | mp_get_tpr_ebx: |
| 126 | mov %eax, %ebx |
| 127 | call mp_get_tpr_eax |
| 128 | xchg %eax, %ebx |
| 129 | ret |
| 130 | |
| 131 | mp_get_tpr_ecx: |
| 132 | mov %eax, %ecx |
| 133 | call mp_get_tpr_eax |
| 134 | xchg %eax, %ecx |
| 135 | ret |
| 136 | |
| 137 | mp_get_tpr_edx: |
| 138 | mov %eax, %edx |
| 139 | call mp_get_tpr_eax |
| 140 | xchg %eax, %edx |
| 141 | ret |
| 142 | |
| 143 | mp_get_tpr_esi: |
| 144 | mov %eax, %esi |
| 145 | call mp_get_tpr_eax |
| 146 | xchg %eax, %esi |
| 147 | ret |
| 148 | |
| 149 | mp_get_tpr_edi: |
| 150 | mov %eax, %edi |
| 151 | call mp_get_tpr_edi |
| 152 | xchg %eax, %edi |
| 153 | ret |
| 154 | |
| 155 | mp_get_tpr_ebp: |
| 156 | mov %eax, %ebp |
| 157 | call mp_get_tpr_eax |
| 158 | xchg %eax, %ebp |
| 159 | ret |
| 160 | |
| 161 | mp_get_tpr_stack: |
| 162 | call mp_get_tpr_eax |
| 163 | xchg %eax, 4(%esp) |
| 164 | ret |
| 165 | |
| 166 | mp_set_tpr_eax: |
| 167 | push %eax |
| 168 | call mp_set_tpr |
| 169 | ret |
| 170 | |
| 171 | mp_set_tpr: |
| 172 | pushf |
| 173 | push %eax |
| 174 | push %ecx |
| 175 | push %edx |
| 176 | push %ebx |
| 177 | cli |
| 178 | reenable_vtpr |
| 179 | |
| 180 | mp_set_tpr_failed: |
| 181 | fs/movzbl pcr_cpu, %edx |
| 182 | |
| 183 | mov vcpu_shift, %ecx ; fixup |
| 184 | shl %cl, %edx |
| 185 | |
| 186 | testb $1, vapic+4(%edx) ; fixup delta=-5 |
| 187 | jz mp_set_tpr_bad |
| 188 | |
| 189 | mov vapic(%edx), %eax ; fixup |
| 190 | |
| 191 | mov %eax, %ebx |
| 192 | mov 24(%esp), %bl |
| 193 | |
| 194 | /* %ebx = new vapic (%bl = tpr, %bh = isr, %b3 = irr) */ |
| 195 | |
| 196 | lock cmpxchg %ebx, vapic(%edx) ; fixup |
| 197 | jnz mp_set_tpr_failed |
| 198 | |
| 199 | /* compute ppr */ |
| 200 | cmp %bh, %bl |
| 201 | jae mp_tpr_is_bigger |
| 202 | mp_isr_is_bigger: |
| 203 | mov %bh, %bl |
| 204 | mp_tpr_is_bigger: |
| 205 | /* %bl = ppr */ |
| 206 | rol $8, %ebx |
| 207 | /* now: %bl = irr, %bh = ppr */ |
| 208 | cmp %bh, %bl |
| 209 | ja mp_set_tpr_poll_irq |
| 210 | |
| 211 | mp_set_tpr_out: |
| 212 | pop %ebx |
| 213 | pop %edx |
| 214 | pop %ecx |
| 215 | pop %eax |
| 216 | popf |
| 217 | ret $4 |
| 218 | |
| 219 | mp_set_tpr_poll_irq: |
| 220 | mov $kvm_hypercall_vapic_poll_irq, %eax |
| 221 | kvm_hypercall |
| 222 | jmp mp_set_tpr_out |
| 223 | |
| 224 | mp_set_tpr_bad: |
| 225 | mov 24(%esp), %ecx |
| 226 | mov real_tpr, %eax ; fixup |
| 227 | mov %ecx, (%eax) |
| 228 | jmp mp_set_tpr_out |
| 229 | |
| 230 | up_get_tpr_eax: |
| 231 | reenable_vtpr |
| 232 | movzbl vapic, %eax ; fixup |
| 233 | ret |
| 234 | |
| 235 | up_get_tpr_ebx: |
| 236 | reenable_vtpr |
| 237 | movzbl vapic, %ebx ; fixup |
| 238 | ret |
| 239 | |
| 240 | up_get_tpr_ecx: |
| 241 | reenable_vtpr |
| 242 | movzbl vapic, %ecx ; fixup |
| 243 | ret |
| 244 | |
| 245 | up_get_tpr_edx: |
| 246 | reenable_vtpr |
| 247 | movzbl vapic, %edx ; fixup |
| 248 | ret |
| 249 | |
| 250 | up_get_tpr_esi: |
| 251 | reenable_vtpr |
| 252 | movzbl vapic, %esi ; fixup |
| 253 | ret |
| 254 | |
| 255 | up_get_tpr_edi: |
| 256 | reenable_vtpr |
| 257 | movzbl vapic, %edi ; fixup |
| 258 | ret |
| 259 | |
| 260 | up_get_tpr_ebp: |
| 261 | reenable_vtpr |
| 262 | movzbl vapic, %ebp ; fixup |
| 263 | ret |
| 264 | |
| 265 | up_get_tpr_stack: |
| 266 | reenable_vtpr |
| 267 | movzbl vapic, %eax ; fixup |
| 268 | xchg %eax, 4(%esp) |
| 269 | ret |
| 270 | |
| 271 | up_set_tpr_eax: |
| 272 | push %eax |
| 273 | call up_set_tpr |
| 274 | ret |
| 275 | |
| 276 | up_set_tpr: |
| 277 | pushf |
| 278 | push %eax |
| 279 | push %ebx |
| 280 | reenable_vtpr |
| 281 | |
| 282 | up_set_tpr_failed: |
| 283 | mov vapic, %eax ; fixup |
| 284 | |
| 285 | mov %eax, %ebx |
| 286 | mov 16(%esp), %bl |
| 287 | |
| 288 | /* %ebx = new vapic (%bl = tpr, %bh = isr, %b3 = irr) */ |
| 289 | |
| 290 | lock cmpxchg %ebx, vapic ; fixup |
| 291 | jnz up_set_tpr_failed |
| 292 | |
| 293 | /* compute ppr */ |
| 294 | cmp %bh, %bl |
| 295 | jae up_tpr_is_bigger |
| 296 | up_isr_is_bigger: |
| 297 | mov %bh, %bl |
| 298 | up_tpr_is_bigger: |
| 299 | /* %bl = ppr */ |
| 300 | rol $8, %ebx |
| 301 | /* now: %bl = irr, %bh = ppr */ |
| 302 | cmp %bh, %bl |
| 303 | ja up_set_tpr_poll_irq |
| 304 | |
| 305 | up_set_tpr_out: |
| 306 | pop %ebx |
| 307 | pop %eax |
| 308 | popf |
| 309 | ret $4 |
| 310 | |
| 311 | up_set_tpr_poll_irq: |
| 312 | mov $kvm_hypercall_vapic_poll_irq, %eax |
| 313 | kvm_hypercall |
| 314 | jmp up_set_tpr_out |
| 315 | |
| 316 | .text 1 |
| 317 | fixup_end = . |
| 318 | .text 0 |
| 319 | |
| 320 | /* |
| 321 | * vapic format: |
| 322 | * per-vcpu records of size 2^vcpu shift. |
| 323 | * byte 0: tpr (r/w) |
| 324 | * byte 1: highest in-service interrupt (isr) (r/o); bits 3:0 are zero |
| 325 | * byte 2: zero (r/o) |
| 326 | * byte 3: highest pending interrupt (irr) (r/o) |
| 327 | */ |
| 328 | .text 2 |
| 329 | |
| 330 | .align 128 |
| 331 | |
| 332 | vapic: |
| 333 | . = . + vapic_size |
| 334 | |
| 335 | OPTION_ROM_END |