root/drivers/gpu/drm/i915/gvt/cfg_space.c

DEFINITIONS

1. vgpu_pci_cfg_mem_write
2. intel_vgpu_emulate_cfg_read
3. map_aperture
4. trap_gttmmio
5. emulate_pci_command_write
6. emulate_pci_rom_bar_write
7. emulate_pci_bar_write
8. intel_vgpu_emulate_cfg_write
9. intel_vgpu_init_cfg_space
10. intel_vgpu_reset_cfg_space

   1 /*
   2  * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eddie Dong <eddie.dong@intel.com>
  25  *    Jike Song <jike.song@intel.com>
  26  *
  27  * Contributors:
  28  *    Zhi Wang <zhi.a.wang@intel.com>
  29  *    Min He <min.he@intel.com>
  30  *    Bing Niu <bing.niu@intel.com>
  31  *
  32  */
  33 
  34 #include "i915_drv.h"
  35 #include "gvt.h"
  36 
  37 enum {
  38         INTEL_GVT_PCI_BAR_GTTMMIO = 0,
  39         INTEL_GVT_PCI_BAR_APERTURE,
  40         INTEL_GVT_PCI_BAR_PIO,
  41         INTEL_GVT_PCI_BAR_MAX,
  42 };
  43 
  44 /* bitmap for writable bits (RW or RW1C bits, but cannot co-exist in one
  45  * byte) byte by byte in standard pci configuration space. (not the full
  46  * 256 bytes.)
  47  */
  48 static const u8 pci_cfg_space_rw_bmp[PCI_INTERRUPT_LINE + 4] = {
  49         [PCI_COMMAND]           = 0xff, 0x07,
  50         [PCI_STATUS]            = 0x00, 0xf9, /* the only one RW1C byte */
  51         [PCI_CACHE_LINE_SIZE]   = 0xff,
  52         [PCI_BASE_ADDRESS_0 ... PCI_CARDBUS_CIS - 1] = 0xff,
  53         [PCI_ROM_ADDRESS]       = 0x01, 0xf8, 0xff, 0xff,
  54         [PCI_INTERRUPT_LINE]    = 0xff,
  55 };
  56 
  57 /**
  58  * vgpu_pci_cfg_mem_write - write virtual cfg space memory
  59  * @vgpu: target vgpu
  60  * @off: offset
  61  * @src: src ptr to write
  62  * @bytes: number of bytes
  63  *
  64  * Use this function to write virtual cfg space memory.
  65  * For standard cfg space, only RW bits can be changed,
  66  * and we emulates the RW1C behavior of PCI_STATUS register.
  67  */
  68 static void vgpu_pci_cfg_mem_write(struct intel_vgpu *vgpu, unsigned int off,
  69                                    u8 *src, unsigned int bytes)
  70 {
  71         u8 *cfg_base = vgpu_cfg_space(vgpu);
  72         u8 mask, new, old;
  73         int i = 0;
  74 
  75         for (; i < bytes && (off + i < sizeof(pci_cfg_space_rw_bmp)); i++) {
  76                 mask = pci_cfg_space_rw_bmp[off + i];
  77                 old = cfg_base[off + i];
  78                 new = src[i] & mask;
  79 
  80                 /**
  81                  * The PCI_STATUS high byte has RW1C bits, here
  82                  * emulates clear by writing 1 for these bits.
  83                  * Writing a 0b to RW1C bits has no effect.
  84                  */
  85                 if (off + i == PCI_STATUS + 1)
  86                         new = (~new & old) & mask;
  87 
  88                 cfg_base[off + i] = (old & ~mask) | new;
  89         }
  90 
  91         /* For other configuration space directly copy as it is. */
  92         if (i < bytes)
  93                 memcpy(cfg_base + off + i, src + i, bytes - i);
  94 }
  95 
  96 /**
  97  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space read
  98  * @vgpu: target vgpu
  99  * @offset: offset
 100  * @p_data: return data ptr
 101  * @bytes: number of bytes to read
 102  *
 103  * Returns:
 104  * Zero on success, negative error code if failed.
 105  */
 106 int intel_vgpu_emulate_cfg_read(struct intel_vgpu *vgpu, unsigned int offset,
 107         void *p_data, unsigned int bytes)
 108 {
 109         if (WARN_ON(bytes > 4))
 110                 return -EINVAL;
 111 
 112         if (WARN_ON(offset + bytes > vgpu->gvt->device_info.cfg_space_size))
 113                 return -EINVAL;
 114 
 115         memcpy(p_data, vgpu_cfg_space(vgpu) + offset, bytes);
 116         return 0;
 117 }
 118 
 119 static int map_aperture(struct intel_vgpu *vgpu, bool map)
 120 {
 121         phys_addr_t aperture_pa = vgpu_aperture_pa_base(vgpu);
 122         unsigned long aperture_sz = vgpu_aperture_sz(vgpu);
 123         u64 first_gfn;
 124         u64 val;
 125         int ret;
 126 
 127         if (map == vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked)
 128                 return 0;
 129 
 130         val = vgpu_cfg_space(vgpu)[PCI_BASE_ADDRESS_2];
 131         if (val & PCI_BASE_ADDRESS_MEM_TYPE_64)
 132                 val = *(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_2);
 133         else
 134                 val = *(u32 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_2);
 135 
 136         first_gfn = (val + vgpu_aperture_offset(vgpu)) >> PAGE_SHIFT;
 137 
 138         ret = intel_gvt_hypervisor_map_gfn_to_mfn(vgpu, first_gfn,
 139                                                   aperture_pa >> PAGE_SHIFT,
 140                                                   aperture_sz >> PAGE_SHIFT,
 141                                                   map);
 142         if (ret)
 143                 return ret;
 144 
 145         vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked = map;
 146         return 0;
 147 }
 148 
 149 static int trap_gttmmio(struct intel_vgpu *vgpu, bool trap)
 150 {
 151         u64 start, end;
 152         u64 val;
 153         int ret;
 154 
 155         if (trap == vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked)
 156                 return 0;
 157 
 158         val = vgpu_cfg_space(vgpu)[PCI_BASE_ADDRESS_0];
 159         if (val & PCI_BASE_ADDRESS_MEM_TYPE_64)
 160                 start = *(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0);
 161         else
 162                 start = *(u32 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0);
 163 
 164         start &= ~GENMASK(3, 0);
 165         end = start + vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size - 1;
 166 
 167         ret = intel_gvt_hypervisor_set_trap_area(vgpu, start, end, trap);
 168         if (ret)
 169                 return ret;
 170 
 171         vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked = trap;
 172         return 0;
 173 }
 174 
 175 static int emulate_pci_command_write(struct intel_vgpu *vgpu,
 176         unsigned int offset, void *p_data, unsigned int bytes)
 177 {
 178         u8 old = vgpu_cfg_space(vgpu)[offset];
 179         u8 new = *(u8 *)p_data;
 180         u8 changed = old ^ new;
 181         int ret;
 182 
 183         vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
 184         if (!(changed & PCI_COMMAND_MEMORY))
 185                 return 0;
 186 
 187         if (old & PCI_COMMAND_MEMORY) {
 188                 ret = trap_gttmmio(vgpu, false);
 189                 if (ret)
 190                         return ret;
 191                 ret = map_aperture(vgpu, false);
 192                 if (ret)
 193                         return ret;
 194         } else {
 195                 ret = trap_gttmmio(vgpu, true);
 196                 if (ret)
 197                         return ret;
 198                 ret = map_aperture(vgpu, true);
 199                 if (ret)
 200                         return ret;
 201         }
 202 
 203         return 0;
 204 }
 205 
 206 static int emulate_pci_rom_bar_write(struct intel_vgpu *vgpu,
 207         unsigned int offset, void *p_data, unsigned int bytes)
 208 {
 209         u32 *pval = (u32 *)(vgpu_cfg_space(vgpu) + offset);
 210         u32 new = *(u32 *)(p_data);
 211 
 212         if ((new & PCI_ROM_ADDRESS_MASK) == PCI_ROM_ADDRESS_MASK)
 213                 /* We don't have rom, return size of 0. */
 214                 *pval = 0;
 215         else
 216                 vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
 217         return 0;
 218 }
 219 
 220 static int emulate_pci_bar_write(struct intel_vgpu *vgpu, unsigned int offset,
 221         void *p_data, unsigned int bytes)
 222 {
 223         u32 new = *(u32 *)(p_data);
 224         bool lo = IS_ALIGNED(offset, 8);
 225         u64 size;
 226         int ret = 0;
 227         bool mmio_enabled =
 228                 vgpu_cfg_space(vgpu)[PCI_COMMAND] & PCI_COMMAND_MEMORY;
 229         struct intel_vgpu_pci_bar *bars = vgpu->cfg_space.bar;
 230 
 231         /*
 232          * Power-up software can determine how much address
 233          * space the device requires by writing a value of
 234          * all 1's to the register and then reading the value
 235          * back. The device will return 0's in all don't-care
 236          * address bits.
 237          */
 238         if (new == 0xffffffff) {
 239                 switch (offset) {
 240                 case PCI_BASE_ADDRESS_0:
 241                 case PCI_BASE_ADDRESS_1:
 242                         size = ~(bars[INTEL_GVT_PCI_BAR_GTTMMIO].size -1);
 243                         intel_vgpu_write_pci_bar(vgpu, offset,
 244                                                 size >> (lo ? 0 : 32), lo);
 245                         /*
 246                          * Untrap the BAR, since guest hasn't configured a
 247                          * valid GPA
 248                          */
 249                         ret = trap_gttmmio(vgpu, false);
 250                         break;
 251                 case PCI_BASE_ADDRESS_2:
 252                 case PCI_BASE_ADDRESS_3:
 253                         size = ~(bars[INTEL_GVT_PCI_BAR_APERTURE].size -1);
 254                         intel_vgpu_write_pci_bar(vgpu, offset,
 255                                                 size >> (lo ? 0 : 32), lo);
 256                         ret = map_aperture(vgpu, false);
 257                         break;
 258                 default:
 259                         /* Unimplemented BARs */
 260                         intel_vgpu_write_pci_bar(vgpu, offset, 0x0, false);
 261                 }
 262         } else {
 263                 switch (offset) {
 264                 case PCI_BASE_ADDRESS_0:
 265                 case PCI_BASE_ADDRESS_1:
 266                         /*
 267                          * Untrap the old BAR first, since guest has
 268                          * re-configured the BAR
 269                          */
 270                         trap_gttmmio(vgpu, false);
 271                         intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
 272                         ret = trap_gttmmio(vgpu, mmio_enabled);
 273                         break;
 274                 case PCI_BASE_ADDRESS_2:
 275                 case PCI_BASE_ADDRESS_3:
 276                         map_aperture(vgpu, false);
 277                         intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
 278                         ret = map_aperture(vgpu, mmio_enabled);
 279                         break;
 280                 default:
 281                         intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
 282                 }
 283         }
 284         return ret;
 285 }
 286 
 287 /**
 288  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space write
 289  * @vgpu: target vgpu
 290  * @offset: offset
 291  * @p_data: write data ptr
 292  * @bytes: number of bytes to write
 293  *
 294  * Returns:
 295  * Zero on success, negative error code if failed.
 296  */
 297 int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
 298         void *p_data, unsigned int bytes)
 299 {
 300         int ret;
 301 
 302         if (WARN_ON(bytes > 4))
 303                 return -EINVAL;
 304 
 305         if (WARN_ON(offset + bytes > vgpu->gvt->device_info.cfg_space_size))
 306                 return -EINVAL;
 307 
 308         /* First check if it's PCI_COMMAND */
 309         if (IS_ALIGNED(offset, 2) && offset == PCI_COMMAND) {
 310                 if (WARN_ON(bytes > 2))
 311                         return -EINVAL;
 312                 return emulate_pci_command_write(vgpu, offset, p_data, bytes);
 313         }
 314 
 315         switch (rounddown(offset, 4)) {
 316         case PCI_ROM_ADDRESS:
 317                 if (WARN_ON(!IS_ALIGNED(offset, 4)))
 318                         return -EINVAL;
 319                 return emulate_pci_rom_bar_write(vgpu, offset, p_data, bytes);
 320 
 321         case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_5:
 322                 if (WARN_ON(!IS_ALIGNED(offset, 4)))
 323                         return -EINVAL;
 324                 return emulate_pci_bar_write(vgpu, offset, p_data, bytes);
 325 
 326         case INTEL_GVT_PCI_SWSCI:
 327                 if (WARN_ON(!IS_ALIGNED(offset, 4)))
 328                         return -EINVAL;
 329                 ret = intel_vgpu_emulate_opregion_request(vgpu, *(u32 *)p_data);
 330                 if (ret)
 331                         return ret;
 332                 break;
 333 
 334         case INTEL_GVT_PCI_OPREGION:
 335                 if (WARN_ON(!IS_ALIGNED(offset, 4)))
 336                         return -EINVAL;
 337                 ret = intel_vgpu_opregion_base_write_handler(vgpu,
 338                                                    *(u32 *)p_data);
 339                 if (ret)
 340                         return ret;
 341 
 342                 vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
 343                 break;
 344         default:
 345                 vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
 346                 break;
 347         }
 348         return 0;
 349 }
 350 
 351 /**
 352  * intel_vgpu_init_cfg_space - init vGPU configuration space when create vGPU
 353  *
 354  * @vgpu: a vGPU
 355  * @primary: is the vGPU presented as primary
 356  *
 357  */
 358 void intel_vgpu_init_cfg_space(struct intel_vgpu *vgpu,
 359                                bool primary)
 360 {
 361         struct intel_gvt *gvt = vgpu->gvt;
 362         const struct intel_gvt_device_info *info = &gvt->device_info;
 363         u16 *gmch_ctl;
 364 
 365         memcpy(vgpu_cfg_space(vgpu), gvt->firmware.cfg_space,
 366                info->cfg_space_size);
 367 
 368         if (!primary) {
 369                 vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] =
 370                         INTEL_GVT_PCI_CLASS_VGA_OTHER;
 371                 vgpu_cfg_space(vgpu)[PCI_CLASS_PROG] =
 372                         INTEL_GVT_PCI_CLASS_VGA_OTHER;
 373         }
 374 
 375         /* Show guest that there isn't any stolen memory.*/
 376         gmch_ctl = (u16 *)(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_GMCH_CONTROL);
 377         *gmch_ctl &= ~(BDW_GMCH_GMS_MASK << BDW_GMCH_GMS_SHIFT);
 378 
 379         intel_vgpu_write_pci_bar(vgpu, PCI_BASE_ADDRESS_2,
 380                                  gvt_aperture_pa_base(gvt), true);
 381 
 382         vgpu_cfg_space(vgpu)[PCI_COMMAND] &= ~(PCI_COMMAND_IO
 383                                              | PCI_COMMAND_MEMORY
 384                                              | PCI_COMMAND_MASTER);
 385         /*
 386          * Clear the bar upper 32bit and let guest to assign the new value
 387          */
 388         memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_1, 0, 4);
 389         memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_3, 0, 4);
 390         memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_4, 0, 8);
 391         memset(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_OPREGION, 0, 4);
 392 
 393         vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size =
 394                                 pci_resource_len(gvt->dev_priv->drm.pdev, 0);
 395         vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].size =
 396                                 pci_resource_len(gvt->dev_priv->drm.pdev, 2);
 397 
 398         memset(vgpu_cfg_space(vgpu) + PCI_ROM_ADDRESS, 0, 4);
 399 }
 400 
 401 /**
 402  * intel_vgpu_reset_cfg_space - reset vGPU configuration space
 403  *
 404  * @vgpu: a vGPU
 405  *
 406  */
 407 void intel_vgpu_reset_cfg_space(struct intel_vgpu *vgpu)
 408 {
 409         u8 cmd = vgpu_cfg_space(vgpu)[PCI_COMMAND];
 410         bool primary = vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] !=
 411                                 INTEL_GVT_PCI_CLASS_VGA_OTHER;
 412 
 413         if (cmd & PCI_COMMAND_MEMORY) {
 414                 trap_gttmmio(vgpu, false);
 415                 map_aperture(vgpu, false);
 416         }
 417 
 418         /**
 419          * Currently we only do such reset when vGPU is not
 420          * owned by any VM, so we simply restore entire cfg
 421          * space to default value.
 422          */
 423         intel_vgpu_init_cfg_space(vgpu, primary);
 424 }