hw/cxl/cxl-host.c

   1 /*
   2  * CXL host parameter parsing routines
   3  *
   4  * Copyright (c) 2022 Huawei
   5  * Modeled loosely on the NUMA options handling in hw/core/numa.c
   6  */
   7
   8 #include "qemu/osdep.h"
   9 #include "qemu/units.h"
  10 #include "qemu/bitmap.h"
  11 #include "qemu/error-report.h"
  12 #include "qapi/error.h"
  13 #include "sysemu/qtest.h"
  14 #include "hw/boards.h"
  15
  16 #include "qapi/qapi-visit-machine.h"
  17 #include "hw/cxl/cxl.h"
  18 #include "hw/cxl/cxl_host.h"
  19 #include "hw/pci/pci_bus.h"
  20 #include "hw/pci/pci_bridge.h"
  21 #include "hw/pci/pci_host.h"
  22 #include "hw/pci/pcie_port.h"
  23 #include "hw/pci-bridge/pci_expander_bridge.h"
  24
  25 static void cxl_fixed_memory_window_config(CXLState *cxl_state,
  26                                            CXLFixedMemoryWindowOptions *object,
  27                                            Error **errp)
  28 {
  29     ERRP_GUARD();
  30     g_autofree CXLFixedWindow *fw = g_malloc0(sizeof(*fw));
  31     strList *target;
  32     int i;
  33
  34     for (target = object->targets; target; target = target->next) {
  35         fw->num_targets++;
  36     }
  37
  38     fw->enc_int_ways = cxl_interleave_ways_enc(fw->num_targets, errp);
  39     if (*errp) {
  40         return;
  41     }
  42
  43     if (object->size % (256 * MiB)) {
  44         error_setg(errp,
  45                    "Size of a CXL fixed memory window must be a multiple of 256MiB");
  46         return;
  47     }
  48     fw->size = object->size;
  49
  50     if (object->has_interleave_granularity) {
  51         fw->enc_int_gran =
  52             cxl_interleave_granularity_enc(object->interleave_granularity,
  53                                            errp);
  54         if (*errp) {
  55             return;
  56         }
  57     } else {
  58         /* Default to 256 byte interleave */
  59         fw->enc_int_gran = 0;
  60     }
  61
  62     fw->targets = g_malloc0_n(fw->num_targets, sizeof(*fw->targets));
  63     for (i = 0, target = object->targets; target; i++, target = target->next) {
  64         /* This link cannot be resolved yet, so stash the name for now */
  65         fw->targets[i] = g_strdup(target->value);
  66     }
  67
  68     cxl_state->fixed_windows = g_list_append(cxl_state->fixed_windows,
  69                                              g_steal_pointer(&fw));
  70
  71     return;
  72 }
  73
  74 void cxl_fmws_link_targets(CXLState *cxl_state, Error **errp)
  75 {
  76     if (cxl_state && cxl_state->fixed_windows) {
  77         GList *it;
  78
  79         for (it = cxl_state->fixed_windows; it; it = it->next) {
  80             CXLFixedWindow *fw = it->data;
  81             int i;
  82
  83             for (i = 0; i < fw->num_targets; i++) {
  84                 Object *o;
  85                 bool ambig;
  86
  87                 o = object_resolve_path_type(fw->targets[i],
  88                                              TYPE_PXB_CXL_DEV,
  89                                              &ambig);
  90                 if (!o) {
  91                     error_setg(errp, "Could not resolve CXLFM target %s",
  92                                fw->targets[i]);
  93                     return;
  94                 }
  95                 fw->target_hbs[i] = PXB_CXL_DEV(o);
  96             }
  97         }
  98     }
  99 }
 100
 101 static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
 102                                 uint8_t *target)
 103 {
 104     int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
 105     unsigned int hdm_count;
 106     bool found = false;
 107     int i;
 108     uint32_t cap;
 109
 110     cap = ldl_le_p(cache_mem + R_CXL_HDM_DECODER_CAPABILITY);
 111     hdm_count = cxl_decoder_count_dec(FIELD_EX32(cap,
 112                                                  CXL_HDM_DECODER_CAPABILITY,
 113                                                  DECODER_COUNT));
 114     for (i = 0; i < hdm_count; i++) {
 115         uint32_t ctrl, ig_enc, iw_enc, target_idx;
 116         uint32_t low, high;
 117         uint64_t base, size;
 118
 119         low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc);
 120         high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc);
 121         base = (low & 0xf0000000) | ((uint64_t)high << 32);
 122         low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc);
 123         high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc);
 124         size = (low & 0xf0000000) | ((uint64_t)high << 32);
 125         if (addr < base || addr >= base + size) {
 126             continue;
 127         }
 128
 129         ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + i * hdm_inc);
 130         if (!FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
 131             return false;
 132         }
 133         found = true;
 134         ig_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IG);
 135         iw_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IW);
 136         target_idx = (addr / cxl_decode_ig(ig_enc)) % (1 << iw_enc);
 137
 138         if (target_idx < 4) {
 139             uint32_t val = ldl_le_p(cache_mem +
 140                                     R_CXL_HDM_DECODER0_TARGET_LIST_LO +
 141                                     i * hdm_inc);
 142             *target = extract32(val, target_idx * 8, 8);
 143         } else {
 144             uint32_t val = ldl_le_p(cache_mem +
 145                                     R_CXL_HDM_DECODER0_TARGET_LIST_HI +
 146                                     i * hdm_inc);
 147             *target = extract32(val, (target_idx - 4) * 8, 8);
 148         }
 149         break;
 150     }
 151
 152     return found;
 153 }
 154
 155 static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
 156 {
 157     CXLComponentState *hb_cstate, *usp_cstate;
 158     PCIHostState *hb;
 159     CXLUpstreamPort *usp;
 160     int rb_index;
 161     uint32_t *cache_mem;
 162     uint8_t target;
 163     bool target_found;
 164     PCIDevice *rp, *d;
 165
 166     /* Address is relative to memory region. Convert to HPA */
 167     addr += fw->base;
 168
 169     rb_index = (addr / cxl_decode_ig(fw->enc_int_gran)) % fw->num_targets;
 170     hb = PCI_HOST_BRIDGE(fw->target_hbs[rb_index]->cxl_host_bridge);
 171     if (!hb || !hb->bus || !pci_bus_is_cxl(hb->bus)) {
 172         return NULL;
 173     }
 174
 175     if (cxl_get_hb_passthrough(hb)) {
 176         rp = pcie_find_port_first(hb->bus);
 177         if (!rp) {
 178             return NULL;
 179         }
 180     } else {
 181         hb_cstate = cxl_get_hb_cstate(hb);
 182         if (!hb_cstate) {
 183             return NULL;
 184         }
 185
 186         cache_mem = hb_cstate->crb.cache_mem_registers;
 187
 188         target_found = cxl_hdm_find_target(cache_mem, addr, &target);
 189         if (!target_found) {
 190             return NULL;
 191         }
 192
 193         rp = pcie_find_port_by_pn(hb->bus, target);
 194         if (!rp) {
 195             return NULL;
 196         }
 197     }
 198
 199     d = pci_bridge_get_sec_bus(PCI_BRIDGE(rp))->devices[0];
 200     if (!d) {
 201         return NULL;
 202     }
 203
 204     if (object_dynamic_cast(OBJECT(d), TYPE_CXL_TYPE3)) {
 205         return d;
 206     }
 207
 208     /*
 209      * Could also be a switch.  Note only one level of switching currently
 210      * supported.
 211      */
 212     if (!object_dynamic_cast(OBJECT(d), TYPE_CXL_USP)) {
 213         return NULL;
 214     }
 215     usp = CXL_USP(d);
 216
 217     usp_cstate = cxl_usp_to_cstate(usp);
 218     if (!usp_cstate) {
 219         return NULL;
 220     }
 221
 222     cache_mem = usp_cstate->crb.cache_mem_registers;
 223
 224     target_found = cxl_hdm_find_target(cache_mem, addr, &target);
 225     if (!target_found) {
 226         return NULL;
 227     }
 228
 229     d = pcie_find_port_by_pn(&PCI_BRIDGE(d)->sec_bus, target);
 230     if (!d) {
 231         return NULL;
 232     }
 233
 234     d = pci_bridge_get_sec_bus(PCI_BRIDGE(d))->devices[0];
 235     if (!d) {
 236         return NULL;
 237     }
 238
 239     if (!object_dynamic_cast(OBJECT(d), TYPE_CXL_TYPE3)) {
 240         return NULL;
 241     }
 242
 243     return d;
 244 }
 245
 246 static MemTxResult cxl_read_cfmws(void *opaque, hwaddr addr, uint64_t *data,
 247                                   unsigned size, MemTxAttrs attrs)
 248 {
 249     CXLFixedWindow *fw = opaque;
 250     PCIDevice *d;
 251
 252     d = cxl_cfmws_find_device(fw, addr);
 253     if (d == NULL) {
 254         *data = 0;
 255         /* Reads to invalid address return poison */
 256         return MEMTX_ERROR;
 257     }
 258
 259     return cxl_type3_read(d, addr + fw->base, data, size, attrs);
 260 }
 261
 262 static MemTxResult cxl_write_cfmws(void *opaque, hwaddr addr,
 263                                    uint64_t data, unsigned size,
 264                                    MemTxAttrs attrs)
 265 {
 266     CXLFixedWindow *fw = opaque;
 267     PCIDevice *d;
 268
 269     d = cxl_cfmws_find_device(fw, addr);
 270     if (d == NULL) {
 271         /* Writes to invalid address are silent */
 272         return MEMTX_OK;
 273     }
 274
 275     return cxl_type3_write(d, addr + fw->base, data, size, attrs);
 276 }
 277
 278 const MemoryRegionOps cfmws_ops = {
 279     .read_with_attrs = cxl_read_cfmws,
 280     .write_with_attrs = cxl_write_cfmws,
 281     .endianness = DEVICE_LITTLE_ENDIAN,
 282     .valid = {
 283         .min_access_size = 1,
 284         .max_access_size = 8,
 285         .unaligned = true,
 286     },
 287     .impl = {
 288         .min_access_size = 1,
 289         .max_access_size = 8,
 290         .unaligned = true,
 291     },
 292 };
 293
 294 static void machine_get_cxl(Object *obj, Visitor *v, const char *name,
 295                             void *opaque, Error **errp)
 296 {
 297     CXLState *cxl_state = opaque;
 298     bool value = cxl_state->is_enabled;
 299
 300     visit_type_bool(v, name, &value, errp);
 301 }
 302
 303 static void machine_set_cxl(Object *obj, Visitor *v, const char *name,
 304                             void *opaque, Error **errp)
 305 {
 306     CXLState *cxl_state = opaque;
 307     bool value;
 308
 309     if (!visit_type_bool(v, name, &value, errp)) {
 310         return;
 311     }
 312     cxl_state->is_enabled = value;
 313 }
 314
 315 static void machine_get_cfmw(Object *obj, Visitor *v, const char *name,
 316                              void *opaque, Error **errp)
 317 {
 318     CXLFixedMemoryWindowOptionsList **list = opaque;
 319
 320     visit_type_CXLFixedMemoryWindowOptionsList(v, name, list, errp);
 321 }
 322
 323 static void machine_set_cfmw(Object *obj, Visitor *v, const char *name,
 324                              void *opaque, Error **errp)
 325 {
 326     CXLState *state = opaque;
 327     CXLFixedMemoryWindowOptionsList *cfmw_list = NULL;
 328     CXLFixedMemoryWindowOptionsList *it;
 329
 330     visit_type_CXLFixedMemoryWindowOptionsList(v, name, &cfmw_list, errp);
 331     if (!cfmw_list) {
 332         return;
 333     }
 334
 335     for (it = cfmw_list; it; it = it->next) {
 336         cxl_fixed_memory_window_config(state, it->value, errp);
 337     }
 338     state->cfmw_list = cfmw_list;
 339 }
 340
 341 void cxl_machine_init(Object *obj, CXLState *state)
 342 {
 343     object_property_add(obj, "cxl", "bool", machine_get_cxl,
 344                         machine_set_cxl, NULL, state);
 345     object_property_set_description(obj, "cxl",
 346                                     "Set on/off to enable/disable "
 347                                     "CXL instantiation");
 348
 349     object_property_add(obj, "cxl-fmw", "CXLFixedMemoryWindow",
 350                         machine_get_cfmw, machine_set_cfmw,
 351                         NULL, state);
 352     object_property_set_description(obj, "cxl-fmw",
 353                                     "CXL Fixed Memory Windows (array)");
 354 }
 355
 356 void cxl_hook_up_pxb_registers(PCIBus *bus, CXLState *state, Error **errp)
 357 {
 358     /* Walk the pci busses looking for pxb busses to hook up */
 359     if (bus) {
 360         QLIST_FOREACH(bus, &bus->child, sibling) {
 361             if (!pci_bus_is_root(bus)) {
 362                 continue;
 363             }
 364             if (pci_bus_is_cxl(bus)) {
 365                 if (!state->is_enabled) {
 366                     error_setg(errp, "CXL host bridges present, but cxl=off");
 367                     return;
 368                 }
 369                 pxb_cxl_hook_up_registers(state, bus, errp);
 370             }
 371         }
 372     }
 373 }