IPXE/ipxe-3fe683e/src/arch/x86/drivers/xen/hvm.c

   1 /*
   2  * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA.
  18  *
  19  * You can also choose to distribute this program under the terms of
  20  * the Unmodified Binary Distribution Licence (as given in the file
  21  * COPYING.UBDL), provided that you have satisfied its requirements.
  22  */
  23
  24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  25
  26 #include <stdint.h>
  27 #include <stdio.h>
  28 #include <errno.h>
  29 #include <ipxe/malloc.h>
  30 #include <ipxe/pci.h>
  31 #include <ipxe/cpuid.h>
  32 #include <ipxe/msr.h>
  33 #include <ipxe/xen.h>
  34 #include <ipxe/xenver.h>
  35 #include <ipxe/xenmem.h>
  36 #include <ipxe/xenstore.h>
  37 #include <ipxe/xenbus.h>
  38 #include <ipxe/xengrant.h>
  39 #include "hvm.h"
  40
  41 /** @file
  42  *
  43  * Xen HVM driver
  44  *
  45  */
  46
  47 /**
  48  * Get CPUID base
  49  *
  50  * @v hvm               HVM device
  51  * @ret rc              Return status code
  52  */
  53 static int hvm_cpuid_base ( struct hvm_device *hvm ) {
  54         struct {
  55                 uint32_t ebx;
  56                 uint32_t ecx;
  57                 uint32_t edx;
  58         } __attribute__ (( packed )) signature;
  59         uint32_t base;
  60         uint32_t version;
  61         uint32_t discard_eax;
  62         uint32_t discard_ebx;
  63         uint32_t discard_ecx;
  64         uint32_t discard_edx;
  65
  66         /* Scan for magic signature */
  67         for ( base = HVM_CPUID_MIN ; base <= HVM_CPUID_MAX ;
  68               base += HVM_CPUID_STEP ) {
  69                 cpuid ( base, 0, &discard_eax, &signature.ebx, &signature.ecx,
  70                         &signature.edx );
  71                 if ( memcmp ( &signature, HVM_CPUID_MAGIC,
  72                               sizeof ( signature ) ) == 0 ) {
  73                         hvm->cpuid_base = base;
  74                         cpuid ( ( base + HVM_CPUID_VERSION ), 0, &version,
  75                                 &discard_ebx, &discard_ecx, &discard_edx );
  76                         DBGC2 ( hvm, "HVM using CPUID base %#08x (v%d.%d)\n",
  77                                 base, ( version >> 16 ), ( version & 0xffff ) );
  78                         return 0;
  79                 }
  80         }
  81
  82         DBGC ( hvm, "HVM could not find hypervisor\n" );
  83         return -ENODEV;
  84 }
  85
  86 /**
  87  * Map hypercall page(s)
  88  *
  89  * @v hvm               HVM device
  90  * @ret rc              Return status code
  91  */
  92 static int hvm_map_hypercall ( struct hvm_device *hvm ) {
  93         uint32_t pages;
  94         uint32_t msr;
  95         uint32_t discard_ecx;
  96         uint32_t discard_edx;
  97         physaddr_t hypercall_phys;
  98         uint32_t version;
  99         static xen_extraversion_t extraversion;
 100         int xenrc;
 101         int rc;
 102
 103         /* Get number of hypercall pages and MSR to use */
 104         cpuid ( ( hvm->cpuid_base + HVM_CPUID_PAGES ), 0, &pages, &msr,
 105                 &discard_ecx, &discard_edx );
 106
 107         /* Allocate pages */
 108         hvm->hypercall_len = ( pages * PAGE_SIZE );
 109         hvm->xen.hypercall = malloc_dma ( hvm->hypercall_len, PAGE_SIZE );
 110         if ( ! hvm->xen.hypercall ) {
 111                 DBGC ( hvm, "HVM could not allocate %d hypercall page(s)\n",
 112                        pages );
 113                 return -ENOMEM;
 114         }
 115         hypercall_phys = virt_to_phys ( hvm->xen.hypercall );
 116         DBGC2 ( hvm, "HVM hypercall page(s) at [%#08lx,%#08lx) via MSR %#08x\n",
 117                 hypercall_phys, ( hypercall_phys + hvm->hypercall_len ), msr );
 118
 119         /* Write to MSR */
 120         wrmsr ( msr, hypercall_phys );
 121
 122         /* Check that hypercall mechanism is working */
 123         version = xenver_version ( &hvm->xen );
 124         if ( ( xenrc = xenver_extraversion ( &hvm->xen, &extraversion ) ) != 0){
 125                 rc = -EXEN ( xenrc );
 126                 DBGC ( hvm, "HVM could not get extraversion: %s\n",
 127                        strerror ( rc ) );
 128                 return rc;
 129         }
 130         DBGC2 ( hvm, "HVM found Xen version %d.%d%s\n",
 131                 ( version >> 16 ), ( version & 0xffff ) , extraversion );
 132
 133         return 0;
 134 }
 135
 136 /**
 137  * Unmap hypercall page(s)
 138  *
 139  * @v hvm               HVM device
 140  */
 141 static void hvm_unmap_hypercall ( struct hvm_device *hvm ) {
 142
 143         /* Free pages */
 144         free_dma ( hvm->xen.hypercall, hvm->hypercall_len );
 145 }
 146
 147 /**
 148  * Allocate and map MMIO space
 149  *
 150  * @v hvm               HVM device
 151  * @v space             Source mapping space
 152  * @v len               Length (must be a multiple of PAGE_SIZE)
 153  * @ret mmio            MMIO space address, or NULL on error
 154  */
 155 static void * hvm_ioremap ( struct hvm_device *hvm, unsigned int space,
 156                             size_t len ) {
 157         struct xen_add_to_physmap add;
 158         struct xen_remove_from_physmap remove;
 159         unsigned int pages = ( len / PAGE_SIZE );
 160         physaddr_t mmio_phys;
 161         unsigned int i;
 162         void *mmio;
 163         int xenrc;
 164         int rc;
 165
 166         /* Sanity check */
 167         assert ( ( len % PAGE_SIZE ) == 0 );
 168
 169         /* Check for available space */
 170         if ( ( hvm->mmio_offset + len ) > hvm->mmio_len ) {
 171                 DBGC ( hvm, "HVM could not allocate %zd bytes of MMIO space "
 172                        "(%zd of %zd remaining)\n", len,
 173                        ( hvm->mmio_len - hvm->mmio_offset ), hvm->mmio_len );
 174                 goto err_no_space;
 175         }
 176
 177         /* Map this space */
 178         mmio = ioremap ( ( hvm->mmio + hvm->mmio_offset ), len );
 179         if ( ! mmio ) {
 180                 DBGC ( hvm, "HVM could not map MMIO space [%08lx,%08lx)\n",
 181                        ( hvm->mmio + hvm->mmio_offset ),
 182                        ( hvm->mmio + hvm->mmio_offset + len ) );
 183                 goto err_ioremap;
 184         }
 185         mmio_phys = virt_to_phys ( mmio );
 186
 187         /* Add to physical address space */
 188         for ( i = 0 ; i < pages ; i++ ) {
 189                 add.domid = DOMID_SELF;
 190                 add.idx = i;
 191                 add.space = space;
 192                 add.gpfn = ( ( mmio_phys / PAGE_SIZE ) + i );
 193                 if ( ( xenrc = xenmem_add_to_physmap ( &hvm->xen, &add ) ) !=0){
 194                         rc = -EXEN ( xenrc );
 195                         DBGC ( hvm, "HVM could not add space %d idx %d at "
 196                                "[%08lx,%08lx): %s\n", space, i,
 197                                ( mmio_phys + ( i * PAGE_SIZE ) ),
 198                                ( mmio_phys + ( ( i + 1 ) * PAGE_SIZE ) ),
 199                                strerror ( rc ) );
 200                         goto err_add_to_physmap;
 201                 }
 202         }
 203
 204         /* Update offset */
 205         hvm->mmio_offset += len;
 206
 207         return mmio;
 208
 209         i = pages;
 210  err_add_to_physmap:
 211         for ( i-- ; ( signed int ) i >= 0 ; i-- ) {
 212                 remove.domid = DOMID_SELF;
 213                 add.gpfn = ( ( mmio_phys / PAGE_SIZE ) + i );
 214                 xenmem_remove_from_physmap ( &hvm->xen, &remove );
 215         }
 216         iounmap ( mmio );
 217  err_ioremap:
 218  err_no_space:
 219         return NULL;
 220 }
 221
 222 /**
 223  * Unmap MMIO space
 224  *
 225  * @v hvm               HVM device
 226  * @v mmio              MMIO space address
 227  * @v len               Length (must be a multiple of PAGE_SIZE)
 228  */
 229 static void hvm_iounmap ( struct hvm_device *hvm, void *mmio, size_t len ) {
 230         struct xen_remove_from_physmap remove;
 231         physaddr_t mmio_phys = virt_to_phys ( mmio );
 232         unsigned int pages = ( len / PAGE_SIZE );
 233         unsigned int i;
 234         int xenrc;
 235         int rc;
 236
 237         /* Unmap this space */
 238         iounmap ( mmio );
 239
 240         /* Remove from physical address space */
 241         for ( i = 0 ; i < pages ; i++ ) {
 242                 remove.domid = DOMID_SELF;
 243                 remove.gpfn = ( ( mmio_phys / PAGE_SIZE ) + i );
 244                 if ( ( xenrc = xenmem_remove_from_physmap ( &hvm->xen,
 245                                                             &remove ) ) != 0 ) {
 246                         rc = -EXEN ( xenrc );
 247                         DBGC ( hvm, "HVM could not remove space [%08lx,%08lx): "
 248                                "%s\n", ( mmio_phys + ( i * PAGE_SIZE ) ),
 249                                ( mmio_phys + ( ( i + 1 ) * PAGE_SIZE ) ),
 250                                strerror ( rc ) );
 251                         /* Nothing we can do about this */
 252                 }
 253         }
 254 }
 255
 256 /**
 257  * Map shared info page
 258  *
 259  * @v hvm               HVM device
 260  * @ret rc              Return status code
 261  */
 262 static int hvm_map_shared_info ( struct hvm_device *hvm ) {
 263         physaddr_t shared_info_phys;
 264         int rc;
 265
 266         /* Map shared info page */
 267         hvm->xen.shared = hvm_ioremap ( hvm, XENMAPSPACE_shared_info,
 268                                         PAGE_SIZE );
 269         if ( ! hvm->xen.shared ) {
 270                 rc = -ENOMEM;
 271                 goto err_alloc;
 272         }
 273         shared_info_phys = virt_to_phys ( hvm->xen.shared );
 274         DBGC2 ( hvm, "HVM shared info page at [%#08lx,%#08lx)\n",
 275                 shared_info_phys, ( shared_info_phys + PAGE_SIZE ) );
 276
 277         /* Sanity check */
 278         DBGC2 ( hvm, "HVM wallclock time is %d\n",
 279                 readl ( &hvm->xen.shared->wc_sec ) );
 280
 281         return 0;
 282
 283         hvm_iounmap ( hvm, hvm->xen.shared, PAGE_SIZE );
 284  err_alloc:
 285         return rc;
 286 }
 287
 288 /**
 289  * Unmap shared info page
 290  *
 291  * @v hvm               HVM device
 292  */
 293 static void hvm_unmap_shared_info ( struct hvm_device *hvm ) {
 294
 295         /* Unmap shared info page */
 296         hvm_iounmap ( hvm, hvm->xen.shared, PAGE_SIZE );
 297 }
 298
 299 /**
 300  * Map grant table
 301  *
 302  * @v hvm               HVM device
 303  * @ret rc              Return status code
 304  */
 305 static int hvm_map_grant ( struct hvm_device *hvm ) {
 306         physaddr_t grant_phys;
 307         int rc;
 308
 309         /* Initialise grant table */
 310         if ( ( rc = xengrant_init ( &hvm->xen ) ) != 0 ) {
 311                 DBGC ( hvm, "HVM could not initialise grant table: %s\n",
 312                        strerror ( rc ) );
 313                 return rc;
 314         }
 315
 316         /* Map grant table */
 317         hvm->xen.grant.table = hvm_ioremap ( hvm, XENMAPSPACE_grant_table,
 318                                              hvm->xen.grant.len );
 319         if ( ! hvm->xen.grant.table )
 320                 return -ENODEV;
 321
 322         grant_phys = virt_to_phys ( hvm->xen.grant.table );
 323         DBGC2 ( hvm, "HVM mapped grant table at [%08lx,%08lx)\n",
 324                 grant_phys, ( grant_phys + hvm->xen.grant.len ) );
 325         return 0;
 326 }
 327
 328 /**
 329  * Unmap grant table
 330  *
 331  * @v hvm               HVM device
 332  */
 333 static void hvm_unmap_grant ( struct hvm_device *hvm ) {
 334
 335         /* Unmap grant table */
 336         hvm_iounmap ( hvm, hvm->xen.grant.table, hvm->xen.grant.len );
 337 }
 338
 339 /**
 340  * Map XenStore
 341  *
 342  * @v hvm               HVM device
 343  * @ret rc              Return status code
 344  */
 345 static int hvm_map_xenstore ( struct hvm_device *hvm ) {
 346         uint64_t xenstore_evtchn;
 347         uint64_t xenstore_pfn;
 348         physaddr_t xenstore_phys;
 349         char *name;
 350         int xenrc;
 351         int rc;
 352
 353         /* Get XenStore event channel */
 354         if ( ( xenrc = xen_hvm_get_param ( &hvm->xen, HVM_PARAM_STORE_EVTCHN,
 355                                            &xenstore_evtchn ) ) != 0 ) {
 356                 rc = -EXEN ( xenrc );
 357                 DBGC ( hvm, "HVM could not get XenStore event channel: %s\n",
 358                        strerror ( rc ) );
 359                 return rc;
 360         }
 361         hvm->xen.store.port = xenstore_evtchn;
 362
 363         /* Get XenStore PFN */
 364         if ( ( xenrc = xen_hvm_get_param ( &hvm->xen, HVM_PARAM_STORE_PFN,
 365                                            &xenstore_pfn ) ) != 0 ) {
 366                 rc = -EXEN ( xenrc );
 367                 DBGC ( hvm, "HVM could not get XenStore PFN: %s\n",
 368                        strerror ( rc ) );
 369                 return rc;
 370         }
 371         xenstore_phys = ( xenstore_pfn * PAGE_SIZE );
 372
 373         /* Map XenStore */
 374         hvm->xen.store.intf = ioremap ( xenstore_phys, PAGE_SIZE );
 375         if ( ! hvm->xen.store.intf ) {
 376                 DBGC ( hvm, "HVM could not map XenStore at [%08lx,%08lx)\n",
 377                        xenstore_phys, ( xenstore_phys + PAGE_SIZE ) );
 378                 return -ENODEV;
 379         }
 380         DBGC2 ( hvm, "HVM mapped XenStore at [%08lx,%08lx) with event port "
 381                 "%d\n", xenstore_phys, ( xenstore_phys + PAGE_SIZE ),
 382                 hvm->xen.store.port );
 383
 384         /* Check that XenStore is working */
 385         if ( ( rc = xenstore_read ( &hvm->xen, &name, "name", NULL ) ) != 0 ) {
 386                 DBGC ( hvm, "HVM could not read domain name: %s\n",
 387                        strerror ( rc ) );
 388                 return rc;
 389         }
 390         DBGC2 ( hvm, "HVM running in domain \"%s\"\n", name );
 391         free ( name );
 392
 393         return 0;
 394 }
 395
 396 /**
 397  * Unmap XenStore
 398  *
 399  * @v hvm               HVM device
 400  */
 401 static void hvm_unmap_xenstore ( struct hvm_device *hvm ) {
 402
 403         /* Unmap XenStore */
 404         iounmap ( hvm->xen.store.intf );
 405 }
 406
 407 /**
 408  * Probe PCI device
 409  *
 410  * @v pci               PCI device
 411  * @ret rc              Return status code
 412  */
 413 static int hvm_probe ( struct pci_device *pci ) {
 414         struct hvm_device *hvm;
 415         int rc;
 416
 417         /* Allocate and initialise structure */
 418         hvm = zalloc ( sizeof ( *hvm ) );
 419         if ( ! hvm ) {
 420                 rc = -ENOMEM;
 421                 goto err_alloc;
 422         }
 423         hvm->mmio = pci_bar_start ( pci, HVM_MMIO_BAR );
 424         hvm->mmio_len = pci_bar_size ( pci, HVM_MMIO_BAR );
 425         DBGC2 ( hvm, "HVM has MMIO space [%08lx,%08lx)\n",
 426                 hvm->mmio, ( hvm->mmio + hvm->mmio_len ) );
 427
 428         /* Fix up PCI device */
 429         adjust_pci_device ( pci );
 430
 431         /* Attach to hypervisor */
 432         if ( ( rc = hvm_cpuid_base ( hvm ) ) != 0 )
 433                 goto err_cpuid_base;
 434         if ( ( rc = hvm_map_hypercall ( hvm ) ) != 0 )
 435                 goto err_map_hypercall;
 436         if ( ( rc = hvm_map_shared_info ( hvm ) ) != 0 )
 437                 goto err_map_shared_info;
 438         if ( ( rc = hvm_map_grant ( hvm ) ) != 0 )
 439                 goto err_map_grant;
 440         if ( ( rc = hvm_map_xenstore ( hvm ) ) != 0 )
 441                 goto err_map_xenstore;
 442
 443         /* Probe Xen devices */
 444         if ( ( rc = xenbus_probe ( &hvm->xen, &pci->dev ) ) != 0 ) {
 445                 DBGC ( hvm, "HVM could not probe Xen bus: %s\n",
 446                        strerror ( rc ) );
 447                 goto err_xenbus_probe;
 448         }
 449
 450         pci_set_drvdata ( pci, hvm );
 451         return 0;
 452
 453         xenbus_remove ( &hvm->xen, &pci->dev );
 454  err_xenbus_probe:
 455         hvm_unmap_xenstore ( hvm );
 456  err_map_xenstore:
 457         hvm_unmap_grant ( hvm );
 458  err_map_grant:
 459         hvm_unmap_shared_info ( hvm );
 460  err_map_shared_info:
 461         hvm_unmap_hypercall ( hvm );
 462  err_map_hypercall:
 463  err_cpuid_base:
 464         free ( hvm );
 465  err_alloc:
 466         return rc;
 467 }
 468
 469 /**
 470  * Remove PCI device
 471  *
 472  * @v pci               PCI device
 473  */
 474 static void hvm_remove ( struct pci_device *pci ) {
 475         struct hvm_device *hvm = pci_get_drvdata ( pci );
 476
 477         xenbus_remove ( &hvm->xen, &pci->dev );
 478         hvm_unmap_xenstore ( hvm );
 479         hvm_unmap_grant ( hvm );
 480         hvm_unmap_shared_info ( hvm );
 481         hvm_unmap_hypercall ( hvm );
 482         free ( hvm );
 483 }
 484
 485 /** PCI device IDs */
 486 static struct pci_device_id hvm_ids[] = {
 487         PCI_ROM ( 0x5853, 0x0001, "hvm", "hvm", 0 ),
 488         PCI_ROM ( 0x5853, 0x0002, "hvm2", "hvm2", 0 ),
 489 };
 490
 491 /** PCI driver */
 492 struct pci_driver hvm_driver __pci_driver = {
 493         .ids = hvm_ids,
 494         .id_count = ( sizeof ( hvm_ids ) / sizeof ( hvm_ids[0] ) ),
 495         .probe = hvm_probe,
 496         .remove = hvm_remove,
 497 };
 498
 499 /* Drag in objects via hvm_driver */
 500 REQUIRING_SYMBOL ( hvm_driver );
 501
 502 /* Drag in netfront driver */
 503 //REQUIRE_OBJECT ( netfront );