root/arch/x86/pci/amd_bus.c

DEFINITIONS

1. find_pci_root_info
2. early_root_info_init
3. amd_bus_cpu_online
4. pci_enable_pci_io_ecs
5. pci_io_ecs_init
6. amd_postcore_init

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/init.h>
   3 #include <linux/pci.h>
   4 #include <linux/topology.h>
   5 #include <linux/cpu.h>
   6 #include <linux/range.h>
   7 
   8 #include <asm/amd_nb.h>
   9 #include <asm/pci_x86.h>
  10 
  11 #include <asm/pci-direct.h>
  12 
  13 #include "bus_numa.h"
  14 
  15 #define AMD_NB_F0_NODE_ID                       0x60
  16 #define AMD_NB_F0_UNIT_ID                       0x64
  17 #define AMD_NB_F1_CONFIG_MAP_REG                0xe0
  18 
  19 #define RANGE_NUM                               16
  20 #define AMD_NB_F1_CONFIG_MAP_RANGES             4
  21 
  22 struct amd_hostbridge {
  23         u32 bus;
  24         u32 slot;
  25         u32 device;
  26 };
  27 
  28 /*
  29  * IMPORTANT NOTE:
  30  * hb_probes[] and early_root_info_init() is in maintenance mode.
  31  * It only supports K8, Fam10h, Fam11h, and Fam15h_00h-0fh .
  32  * Future processor will rely on information in ACPI.
  33  */
  34 static struct amd_hostbridge hb_probes[] __initdata = {
  35         { 0, 0x18, 0x1100 }, /* K8 */
  36         { 0, 0x18, 0x1200 }, /* Family10h */
  37         { 0xff, 0, 0x1200 }, /* Family10h */
  38         { 0, 0x18, 0x1300 }, /* Family11h */
  39         { 0, 0x18, 0x1600 }, /* Family15h */
  40 };
  41 
  42 static struct pci_root_info __init *find_pci_root_info(int node, int link)
  43 {
  44         struct pci_root_info *info;
  45 
  46         /* find the position */
  47         list_for_each_entry(info, &pci_root_infos, list)
  48                 if (info->node == node && info->link == link)
  49                         return info;
  50 
  51         return NULL;
  52 }
  53 
  54 /**
  55  * early_root_info_init()
  56  * called before pcibios_scan_root and pci_scan_bus
  57  * fills the mp_bus_to_cpumask array based according
  58  * to the LDT Bus Number Registers found in the northbridge.
  59  */
  60 static int __init early_root_info_init(void)
  61 {
  62         int i;
  63         unsigned bus;
  64         unsigned slot;
  65         int node;
  66         int link;
  67         int def_node;
  68         int def_link;
  69         struct pci_root_info *info;
  70         u32 reg;
  71         u64 start;
  72         u64 end;
  73         struct range range[RANGE_NUM];
  74         u64 val;
  75         u32 address;
  76         bool found;
  77         struct resource fam10h_mmconf_res, *fam10h_mmconf;
  78         u64 fam10h_mmconf_start;
  79         u64 fam10h_mmconf_end;
  80 
  81         if (!early_pci_allowed())
  82                 return -1;
  83 
  84         found = false;
  85         for (i = 0; i < ARRAY_SIZE(hb_probes); i++) {
  86                 u32 id;
  87                 u16 device;
  88                 u16 vendor;
  89 
  90                 bus = hb_probes[i].bus;
  91                 slot = hb_probes[i].slot;
  92                 id = read_pci_config(bus, slot, 0, PCI_VENDOR_ID);
  93                 vendor = id & 0xffff;
  94                 device = (id>>16) & 0xffff;
  95 
  96                 if (vendor != PCI_VENDOR_ID_AMD &&
  97                     vendor != PCI_VENDOR_ID_HYGON)
  98                         continue;
  99 
 100                 if (hb_probes[i].device == device) {
 101                         found = true;
 102                         break;
 103                 }
 104         }
 105 
 106         if (!found)
 107                 return 0;
 108 
 109         /*
 110          * We should learn topology and routing information from _PXM and
 111          * _CRS methods in the ACPI namespace.  We extract node numbers
 112          * here to work around BIOSes that don't supply _PXM.
 113          */
 114         for (i = 0; i < AMD_NB_F1_CONFIG_MAP_RANGES; i++) {
 115                 int min_bus;
 116                 int max_bus;
 117                 reg = read_pci_config(bus, slot, 1,
 118                                 AMD_NB_F1_CONFIG_MAP_REG + (i << 2));
 119 
 120                 /* Check if that register is enabled for bus range */
 121                 if ((reg & 7) != 3)
 122                         continue;
 123 
 124                 min_bus = (reg >> 16) & 0xff;
 125                 max_bus = (reg >> 24) & 0xff;
 126                 node = (reg >> 4) & 0x07;
 127                 link = (reg >> 8) & 0x03;
 128 
 129                 info = alloc_pci_root_info(min_bus, max_bus, node, link);
 130         }
 131 
 132         /*
 133          * The following code extracts routing information for use on old
 134          * systems where Linux doesn't automatically use host bridge _CRS
 135          * methods (or when the user specifies "pci=nocrs").
 136          *
 137          * We only do this through Fam11h, because _CRS should be enough on
 138          * newer systems.
 139          */
 140         if (boot_cpu_data.x86 > 0x11)
 141                 return 0;
 142 
 143         /* get the default node and link for left over res */
 144         reg = read_pci_config(bus, slot, 0, AMD_NB_F0_NODE_ID);
 145         def_node = (reg >> 8) & 0x07;
 146         reg = read_pci_config(bus, slot, 0, AMD_NB_F0_UNIT_ID);
 147         def_link = (reg >> 8) & 0x03;
 148 
 149         memset(range, 0, sizeof(range));
 150         add_range(range, RANGE_NUM, 0, 0, 0xffff + 1);
 151         /* io port resource */
 152         for (i = 0; i < 4; i++) {
 153                 reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
 154                 if (!(reg & 3))
 155                         continue;
 156 
 157                 start = reg & 0xfff000;
 158                 reg = read_pci_config(bus, slot, 1, 0xc4 + (i << 3));
 159                 node = reg & 0x07;
 160                 link = (reg >> 4) & 0x03;
 161                 end = (reg & 0xfff000) | 0xfff;
 162 
 163                 info = find_pci_root_info(node, link);
 164                 if (!info)
 165                         continue; /* not found */
 166 
 167                 printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
 168                        node, link, start, end);
 169 
 170                 /* kernel only handle 16 bit only */
 171                 if (end > 0xffff)
 172                         end = 0xffff;
 173                 update_res(info, start, end, IORESOURCE_IO, 1);
 174                 subtract_range(range, RANGE_NUM, start, end + 1);
 175         }
 176         /* add left over io port range to def node/link, [0, 0xffff] */
 177         /* find the position */
 178         info = find_pci_root_info(def_node, def_link);
 179         if (info) {
 180                 for (i = 0; i < RANGE_NUM; i++) {
 181                         if (!range[i].end)
 182                                 continue;
 183 
 184                         update_res(info, range[i].start, range[i].end - 1,
 185                                    IORESOURCE_IO, 1);
 186                 }
 187         }
 188 
 189         memset(range, 0, sizeof(range));
 190         /* 0xfd00000000-0xffffffffff for HT */
 191         end = cap_resource((0xfdULL<<32) - 1);
 192         end++;
 193         add_range(range, RANGE_NUM, 0, 0, end);
 194 
 195         /* need to take out [0, TOM) for RAM*/
 196         address = MSR_K8_TOP_MEM1;
 197         rdmsrl(address, val);
 198         end = (val & 0xffffff800000ULL);
 199         printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
 200         if (end < (1ULL<<32))
 201                 subtract_range(range, RANGE_NUM, 0, end);
 202 
 203         /* get mmconfig */
 204         fam10h_mmconf = amd_get_mmconfig_range(&fam10h_mmconf_res);
 205         /* need to take out mmconf range */
 206         if (fam10h_mmconf) {
 207                 printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
 208                 fam10h_mmconf_start = fam10h_mmconf->start;
 209                 fam10h_mmconf_end = fam10h_mmconf->end;
 210                 subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
 211                                  fam10h_mmconf_end + 1);
 212         } else {
 213                 fam10h_mmconf_start = 0;
 214                 fam10h_mmconf_end = 0;
 215         }
 216 
 217         /* mmio resource */
 218         for (i = 0; i < 8; i++) {
 219                 reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
 220                 if (!(reg & 3))
 221                         continue;
 222 
 223                 start = reg & 0xffffff00; /* 39:16 on 31:8*/
 224                 start <<= 8;
 225                 reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
 226                 node = reg & 0x07;
 227                 link = (reg >> 4) & 0x03;
 228                 end = (reg & 0xffffff00);
 229                 end <<= 8;
 230                 end |= 0xffff;
 231 
 232                 info = find_pci_root_info(node, link);
 233 
 234                 if (!info)
 235                         continue;
 236 
 237                 printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
 238                        node, link, start, end);
 239                 /*
 240                  * some sick allocation would have range overlap with fam10h
 241                  * mmconf range, so need to update start and end.
 242                  */
 243                 if (fam10h_mmconf_end) {
 244                         int changed = 0;
 245                         u64 endx = 0;
 246                         if (start >= fam10h_mmconf_start &&
 247                             start <= fam10h_mmconf_end) {
 248                                 start = fam10h_mmconf_end + 1;
 249                                 changed = 1;
 250                         }
 251 
 252                         if (end >= fam10h_mmconf_start &&
 253                             end <= fam10h_mmconf_end) {
 254                                 end = fam10h_mmconf_start - 1;
 255                                 changed = 1;
 256                         }
 257 
 258                         if (start < fam10h_mmconf_start &&
 259                             end > fam10h_mmconf_end) {
 260                                 /* we got a hole */
 261                                 endx = fam10h_mmconf_start - 1;
 262                                 update_res(info, start, endx, IORESOURCE_MEM, 0);
 263                                 subtract_range(range, RANGE_NUM, start,
 264                                                  endx + 1);
 265                                 printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
 266                                 start = fam10h_mmconf_end + 1;
 267                                 changed = 1;
 268                         }
 269                         if (changed) {
 270                                 if (start <= end) {
 271                                         printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
 272                                 } else {
 273                                         printk(KERN_CONT "%s\n", endx?"":" ==> none");
 274                                         continue;
 275                                 }
 276                         }
 277                 }
 278 
 279                 update_res(info, cap_resource(start), cap_resource(end),
 280                                  IORESOURCE_MEM, 1);
 281                 subtract_range(range, RANGE_NUM, start, end + 1);
 282                 printk(KERN_CONT "\n");
 283         }
 284 
 285         /* need to take out [4G, TOM2) for RAM*/
 286         /* SYS_CFG */
 287         address = MSR_K8_SYSCFG;
 288         rdmsrl(address, val);
 289         /* TOP_MEM2 is enabled? */
 290         if (val & (1<<21)) {
 291                 /* TOP_MEM2 */
 292                 address = MSR_K8_TOP_MEM2;
 293                 rdmsrl(address, val);
 294                 end = (val & 0xffffff800000ULL);
 295                 printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
 296                 subtract_range(range, RANGE_NUM, 1ULL<<32, end);
 297         }
 298 
 299         /*
 300          * add left over mmio range to def node/link ?
 301          * that is tricky, just record range in from start_min to 4G
 302          */
 303         info = find_pci_root_info(def_node, def_link);
 304         if (info) {
 305                 for (i = 0; i < RANGE_NUM; i++) {
 306                         if (!range[i].end)
 307                                 continue;
 308 
 309                         update_res(info, cap_resource(range[i].start),
 310                                    cap_resource(range[i].end - 1),
 311                                    IORESOURCE_MEM, 1);
 312                 }
 313         }
 314 
 315         list_for_each_entry(info, &pci_root_infos, list) {
 316                 int busnum;
 317                 struct pci_root_res *root_res;
 318 
 319                 busnum = info->busn.start;
 320                 printk(KERN_DEBUG "bus: %pR on node %x link %x\n",
 321                        &info->busn, info->node, info->link);
 322                 list_for_each_entry(root_res, &info->resources, list)
 323                         printk(KERN_DEBUG "bus: %02x %pR\n",
 324                                        busnum, &root_res->res);
 325         }
 326 
 327         return 0;
 328 }
 329 
 330 #define ENABLE_CF8_EXT_CFG      (1ULL << 46)
 331 
 332 static int amd_bus_cpu_online(unsigned int cpu)
 333 {
 334         u64 reg;
 335 
 336         rdmsrl(MSR_AMD64_NB_CFG, reg);
 337         if (!(reg & ENABLE_CF8_EXT_CFG)) {
 338                 reg |= ENABLE_CF8_EXT_CFG;
 339                 wrmsrl(MSR_AMD64_NB_CFG, reg);
 340         }
 341         return 0;
 342 }
 343 
 344 static void __init pci_enable_pci_io_ecs(void)
 345 {
 346 #ifdef CONFIG_AMD_NB
 347         unsigned int i, n;
 348 
 349         for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
 350                 u8 bus = amd_nb_bus_dev_ranges[i].bus;
 351                 u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
 352                 u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
 353 
 354                 for (; slot < limit; ++slot) {
 355                         u32 val = read_pci_config(bus, slot, 3, 0);
 356 
 357                         if (!early_is_amd_nb(val))
 358                                 continue;
 359 
 360                         val = read_pci_config(bus, slot, 3, 0x8c);
 361                         if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
 362                                 val |= ENABLE_CF8_EXT_CFG >> 32;
 363                                 write_pci_config(bus, slot, 3, 0x8c, val);
 364                         }
 365                         ++n;
 366                 }
 367         }
 368 #endif
 369 }
 370 
 371 static int __init pci_io_ecs_init(void)
 372 {
 373         int ret;
 374 
 375         /* assume all cpus from fam10h have IO ECS */
 376         if (boot_cpu_data.x86 < 0x10)
 377                 return 0;
 378 
 379         /* Try the PCI method first. */
 380         if (early_pci_allowed())
 381                 pci_enable_pci_io_ecs();
 382 
 383         ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "pci/amd_bus:online",
 384                                 amd_bus_cpu_online, NULL);
 385         WARN_ON(ret < 0);
 386 
 387         pci_probe |= PCI_HAS_IO_ECS;
 388 
 389         return 0;
 390 }
 391 
 392 static int __init amd_postcore_init(void)
 393 {
 394         if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
 395             boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
 396                 return 0;
 397 
 398         early_root_info_init();
 399         pci_io_ecs_init();
 400 
 401         return 0;
 402 }
 403 
 404 postcore_initcall(amd_postcore_init);