hw/tpm/tpm_crb.c

   1 /*
   2  * tpm_crb.c - QEMU's TPM CRB interface emulator
   3  *
   4  * Copyright (c) 2018 Red Hat, Inc.
   5  *
   6  * Authors:
   7  *   Marc-André Lureau <marcandre.lureau@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  *
  12  * tpm_crb is a device for TPM 2.0 Command Response Buffer (CRB) Interface
  13  * as defined in TCG PC Client Platform TPM Profile (PTP) Specification
  14  * Family “2.0” Level 00 Revision 01.03 v22
  15  */
  16
  17 #include "qemu/osdep.h"
  18
  19 #include "qemu/module.h"
  20 #include "qapi/error.h"
  21 #include "exec/address-spaces.h"
  22
  23 #include "hw/qdev-core.h"
  24 #include "hw/qdev-properties.h"
  25 #include "hw/pci/pci_ids.h"
  26 #include "hw/acpi/tpm.h"
  27 #include "migration/vmstate.h"
  28 #include "sysemu/tpm_backend.h"
  29 #include "sysemu/reset.h"
  30 #include "tpm_int.h"
  31 #include "tpm_util.h"
  32 #include "tpm_ppi.h"
  33 #include "trace.h"
  34
  35 typedef struct CRBState {
  36     DeviceState parent_obj;
  37
  38     TPMBackend *tpmbe;
  39     TPMBackendCmd cmd;
  40     uint32_t regs[TPM_CRB_R_MAX];
  41     MemoryRegion mmio;
  42     MemoryRegion cmdmem;
  43
  44     size_t be_buffer_size;
  45
  46     bool ppi_enabled;
  47     TPMPPI ppi;
  48 } CRBState;
  49
  50 #define CRB(obj) OBJECT_CHECK(CRBState, (obj), TYPE_TPM_CRB)
  51
  52 #define CRB_INTF_TYPE_CRB_ACTIVE 0b1
  53 #define CRB_INTF_VERSION_CRB 0b1
  54 #define CRB_INTF_CAP_LOCALITY_0_ONLY 0b0
  55 #define CRB_INTF_CAP_IDLE_FAST 0b0
  56 #define CRB_INTF_CAP_XFER_SIZE_64 0b11
  57 #define CRB_INTF_CAP_FIFO_NOT_SUPPORTED 0b0
  58 #define CRB_INTF_CAP_CRB_SUPPORTED 0b1
  59 #define CRB_INTF_IF_SELECTOR_CRB 0b1
  60
  61 #define CRB_CTRL_CMD_SIZE (TPM_CRB_ADDR_SIZE - A_CRB_DATA_BUFFER)
  62
  63 enum crb_loc_ctrl {
  64     CRB_LOC_CTRL_REQUEST_ACCESS = BIT(0),
  65     CRB_LOC_CTRL_RELINQUISH = BIT(1),
  66     CRB_LOC_CTRL_SEIZE = BIT(2),
  67     CRB_LOC_CTRL_RESET_ESTABLISHMENT_BIT = BIT(3),
  68 };
  69
  70 enum crb_ctrl_req {
  71     CRB_CTRL_REQ_CMD_READY = BIT(0),
  72     CRB_CTRL_REQ_GO_IDLE = BIT(1),
  73 };
  74
  75 enum crb_start {
  76     CRB_START_INVOKE = BIT(0),
  77 };
  78
  79 enum crb_cancel {
  80     CRB_CANCEL_INVOKE = BIT(0),
  81 };
  82
  83 #define TPM_CRB_NO_LOCALITY 0xff
  84
  85 static uint64_t tpm_crb_mmio_read(void *opaque, hwaddr addr,
  86                                   unsigned size)
  87 {
  88     CRBState *s = CRB(opaque);
  89     void *regs = (void *)&s->regs + (addr & ~3);
  90     unsigned offset = addr & 3;
  91     uint32_t val = *(uint32_t *)regs >> (8 * offset);
  92
  93     switch (addr) {
  94     case A_CRB_LOC_STATE:
  95         val |= !tpm_backend_get_tpm_established_flag(s->tpmbe);
  96         break;
  97     }
  98
  99     trace_tpm_crb_mmio_read(addr, size, val);
 100
 101     return val;
 102 }
 103
 104 static uint8_t tpm_crb_get_active_locty(CRBState *s)
 105 {
 106     if (!ARRAY_FIELD_EX32(s->regs, CRB_LOC_STATE, locAssigned)) {
 107         return TPM_CRB_NO_LOCALITY;
 108     }
 109     return ARRAY_FIELD_EX32(s->regs, CRB_LOC_STATE, activeLocality);
 110 }
 111
 112 static void tpm_crb_mmio_write(void *opaque, hwaddr addr,
 113                                uint64_t val, unsigned size)
 114 {
 115     CRBState *s = CRB(opaque);
 116     uint8_t locty =  addr >> 12;
 117
 118     trace_tpm_crb_mmio_write(addr, size, val);
 119
 120     switch (addr) {
 121     case A_CRB_CTRL_REQ:
 122         switch (val) {
 123         case CRB_CTRL_REQ_CMD_READY:
 124             ARRAY_FIELD_DP32(s->regs, CRB_CTRL_STS,
 125                              tpmIdle, 0);
 126             break;
 127         case CRB_CTRL_REQ_GO_IDLE:
 128             ARRAY_FIELD_DP32(s->regs, CRB_CTRL_STS,
 129                              tpmIdle, 1);
 130             break;
 131         }
 132         break;
 133     case A_CRB_CTRL_CANCEL:
 134         if (val == CRB_CANCEL_INVOKE &&
 135             s->regs[R_CRB_CTRL_START] & CRB_START_INVOKE) {
 136             tpm_backend_cancel_cmd(s->tpmbe);
 137         }
 138         break;
 139     case A_CRB_CTRL_START:
 140         if (val == CRB_START_INVOKE &&
 141             !(s->regs[R_CRB_CTRL_START] & CRB_START_INVOKE) &&
 142             tpm_crb_get_active_locty(s) == locty) {
 143             void *mem = memory_region_get_ram_ptr(&s->cmdmem);
 144
 145             s->regs[R_CRB_CTRL_START] |= CRB_START_INVOKE;
 146             s->cmd = (TPMBackendCmd) {
 147                 .in = mem,
 148                 .in_len = MIN(tpm_cmd_get_size(mem), s->be_buffer_size),
 149                 .out = mem,
 150                 .out_len = s->be_buffer_size,
 151             };
 152
 153             tpm_backend_deliver_request(s->tpmbe, &s->cmd);
 154         }
 155         break;
 156     case A_CRB_LOC_CTRL:
 157         switch (val) {
 158         case CRB_LOC_CTRL_RESET_ESTABLISHMENT_BIT:
 159             /* not loc 3 or 4 */
 160             break;
 161         case CRB_LOC_CTRL_RELINQUISH:
 162             ARRAY_FIELD_DP32(s->regs, CRB_LOC_STATE,
 163                              locAssigned, 0);
 164             ARRAY_FIELD_DP32(s->regs, CRB_LOC_STS,
 165                              Granted, 0);
 166             break;
 167         case CRB_LOC_CTRL_REQUEST_ACCESS:
 168             ARRAY_FIELD_DP32(s->regs, CRB_LOC_STS,
 169                              Granted, 1);
 170             ARRAY_FIELD_DP32(s->regs, CRB_LOC_STS,
 171                              beenSeized, 0);
 172             ARRAY_FIELD_DP32(s->regs, CRB_LOC_STATE,
 173                              locAssigned, 1);
 174             break;
 175         }
 176         break;
 177     }
 178 }
 179
 180 static const MemoryRegionOps tpm_crb_memory_ops = {
 181     .read = tpm_crb_mmio_read,
 182     .write = tpm_crb_mmio_write,
 183     .endianness = DEVICE_LITTLE_ENDIAN,
 184     .valid = {
 185         .min_access_size = 1,
 186         .max_access_size = 4,
 187     },
 188 };
 189
 190 static void tpm_crb_request_completed(TPMIf *ti, int ret)
 191 {
 192     CRBState *s = CRB(ti);
 193
 194     s->regs[R_CRB_CTRL_START] &= ~CRB_START_INVOKE;
 195     if (ret != 0) {
 196         ARRAY_FIELD_DP32(s->regs, CRB_CTRL_STS,
 197                          tpmSts, 1); /* fatal error */
 198     }
 199 }
 200
 201 static enum TPMVersion tpm_crb_get_version(TPMIf *ti)
 202 {
 203     CRBState *s = CRB(ti);
 204
 205     return tpm_backend_get_tpm_version(s->tpmbe);
 206 }
 207
 208 static int tpm_crb_pre_save(void *opaque)
 209 {
 210     CRBState *s = opaque;
 211
 212     tpm_backend_finish_sync(s->tpmbe);
 213
 214     return 0;
 215 }
 216
 217 static const VMStateDescription vmstate_tpm_crb = {
 218     .name = "tpm-crb",
 219     .pre_save = tpm_crb_pre_save,
 220     .fields = (VMStateField[]) {
 221         VMSTATE_UINT32_ARRAY(regs, CRBState, TPM_CRB_R_MAX),
 222         VMSTATE_END_OF_LIST(),
 223     }
 224 };
 225
 226 static Property tpm_crb_properties[] = {
 227     DEFINE_PROP_TPMBE("tpmdev", CRBState, tpmbe),
 228     DEFINE_PROP_BOOL("ppi", CRBState, ppi_enabled, true),
 229     DEFINE_PROP_END_OF_LIST(),
 230 };
 231
 232 static void tpm_crb_reset(void *dev)
 233 {
 234     CRBState *s = CRB(dev);
 235
 236     if (s->ppi_enabled) {
 237         tpm_ppi_reset(&s->ppi);
 238     }
 239     tpm_backend_reset(s->tpmbe);
 240
 241     memset(s->regs, 0, sizeof(s->regs));
 242
 243     ARRAY_FIELD_DP32(s->regs, CRB_LOC_STATE,
 244                      tpmRegValidSts, 1);
 245     ARRAY_FIELD_DP32(s->regs, CRB_CTRL_STS,
 246                      tpmIdle, 1);
 247     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 248                      InterfaceType, CRB_INTF_TYPE_CRB_ACTIVE);
 249     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 250                      InterfaceVersion, CRB_INTF_VERSION_CRB);
 251     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 252                      CapLocality, CRB_INTF_CAP_LOCALITY_0_ONLY);
 253     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 254                      CapCRBIdleBypass, CRB_INTF_CAP_IDLE_FAST);
 255     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 256                      CapDataXferSizeSupport, CRB_INTF_CAP_XFER_SIZE_64);
 257     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 258                      CapFIFO, CRB_INTF_CAP_FIFO_NOT_SUPPORTED);
 259     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 260                      CapCRB, CRB_INTF_CAP_CRB_SUPPORTED);
 261     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 262                      InterfaceSelector, CRB_INTF_IF_SELECTOR_CRB);
 263     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID,
 264                      RID, 0b0000);
 265     ARRAY_FIELD_DP32(s->regs, CRB_INTF_ID2,
 266                      VID, PCI_VENDOR_ID_IBM);
 267
 268     s->regs[R_CRB_CTRL_CMD_SIZE] = CRB_CTRL_CMD_SIZE;
 269     s->regs[R_CRB_CTRL_CMD_LADDR] = TPM_CRB_ADDR_BASE + A_CRB_DATA_BUFFER;
 270     s->regs[R_CRB_CTRL_RSP_SIZE] = CRB_CTRL_CMD_SIZE;
 271     s->regs[R_CRB_CTRL_RSP_ADDR] = TPM_CRB_ADDR_BASE + A_CRB_DATA_BUFFER;
 272
 273     s->be_buffer_size = MIN(tpm_backend_get_buffer_size(s->tpmbe),
 274                             CRB_CTRL_CMD_SIZE);
 275
 276     tpm_backend_startup_tpm(s->tpmbe, s->be_buffer_size);
 277 }
 278
 279 static void tpm_crb_realize(DeviceState *dev, Error **errp)
 280 {
 281     CRBState *s = CRB(dev);
 282
 283     if (!tpm_find()) {
 284         error_setg(errp, "at most one TPM device is permitted");
 285         return;
 286     }
 287     if (!s->tpmbe) {
 288         error_setg(errp, "'tpmdev' property is required");
 289         return;
 290     }
 291
 292     memory_region_init_io(&s->mmio, OBJECT(s), &tpm_crb_memory_ops, s,
 293         "tpm-crb-mmio", sizeof(s->regs));
 294     memory_region_init_ram(&s->cmdmem, OBJECT(s),
 295         "tpm-crb-cmd", CRB_CTRL_CMD_SIZE, errp);
 296
 297     memory_region_add_subregion(get_system_memory(),
 298         TPM_CRB_ADDR_BASE, &s->mmio);
 299     memory_region_add_subregion(get_system_memory(),
 300         TPM_CRB_ADDR_BASE + sizeof(s->regs), &s->cmdmem);
 301
 302     if (s->ppi_enabled) {
 303         tpm_ppi_init(&s->ppi, get_system_memory(),
 304                      TPM_PPI_ADDR_BASE, OBJECT(s));
 305     }
 306
 307     qemu_register_reset(tpm_crb_reset, dev);
 308 }
 309
 310 static void tpm_crb_class_init(ObjectClass *klass, void *data)
 311 {
 312     DeviceClass *dc = DEVICE_CLASS(klass);
 313     TPMIfClass *tc = TPM_IF_CLASS(klass);
 314
 315     dc->realize = tpm_crb_realize;
 316     dc->props = tpm_crb_properties;
 317     dc->vmsd  = &vmstate_tpm_crb;
 318     dc->user_creatable = true;
 319     tc->model = TPM_MODEL_TPM_CRB;
 320     tc->get_version = tpm_crb_get_version;
 321     tc->request_completed = tpm_crb_request_completed;
 322
 323     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 324 }
 325
 326 static const TypeInfo tpm_crb_info = {
 327     .name = TYPE_TPM_CRB,
 328     /* could be TYPE_SYS_BUS_DEVICE (or LPC etc) */
 329     .parent = TYPE_DEVICE,
 330     .instance_size = sizeof(CRBState),
 331     .class_init  = tpm_crb_class_init,
 332     .interfaces = (InterfaceInfo[]) {
 333         { TYPE_TPM_IF },
 334         { }
 335     }
 336 };
 337
 338 static void tpm_crb_register(void)
 339 {
 340     type_register_static(&tpm_crb_info);
 341 }
 342
 343 type_init(tpm_crb_register)