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
22struct 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 */
34static 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
42static 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
54static inline resource_size_t cap_resource(u64 val)
55{
56 if (val > RESOURCE_SIZE_MAX)
57 return RESOURCE_SIZE_MAX;
58
59 return val;
60}
61
62/**
63 * early_root_info_init()
64 * called before pcibios_scan_root and pci_scan_bus
65 * fills the mp_bus_to_cpumask array based according
66 * to the LDT Bus Number Registers found in the northbridge.
67 */
68static int __init early_root_info_init(void)
69{
70 int i;
71 unsigned bus;
72 unsigned slot;
73 int node;
74 int link;
75 int def_node;
76 int def_link;
77 struct pci_root_info *info;
78 u32 reg;
79 u64 start;
80 u64 end;
81 struct range range[RANGE_NUM];
82 u64 val;
83 u32 address;
84 bool found;
85 struct resource fam10h_mmconf_res, *fam10h_mmconf;
86 u64 fam10h_mmconf_start;
87 u64 fam10h_mmconf_end;
88
89 if (!early_pci_allowed())
90 return -1;
91
92 found = false;
93 for (i = 0; i < ARRAY_SIZE(hb_probes); i++) {
94 u32 id;
95 u16 device;
96 u16 vendor;
97
98 bus = hb_probes[i].bus;
99 slot = hb_probes[i].slot;
100 id = read_pci_config(bus, slot, func: 0, PCI_VENDOR_ID);
101 vendor = id & 0xffff;
102 device = (id>>16) & 0xffff;
103
104 if (vendor != PCI_VENDOR_ID_AMD &&
105 vendor != PCI_VENDOR_ID_HYGON)
106 continue;
107
108 if (hb_probes[i].device == device) {
109 found = true;
110 break;
111 }
112 }
113
114 if (!found)
115 return 0;
116
117 /*
118 * We should learn topology and routing information from _PXM and
119 * _CRS methods in the ACPI namespace. We extract node numbers
120 * here to work around BIOSes that don't supply _PXM.
121 */
122 for (i = 0; i < AMD_NB_F1_CONFIG_MAP_RANGES; i++) {
123 int min_bus;
124 int max_bus;
125 reg = read_pci_config(bus, slot, func: 1,
126 AMD_NB_F1_CONFIG_MAP_REG + (i << 2));
127
128 /* Check if that register is enabled for bus range */
129 if ((reg & 7) != 3)
130 continue;
131
132 min_bus = (reg >> 16) & 0xff;
133 max_bus = (reg >> 24) & 0xff;
134 node = (reg >> 4) & 0x07;
135 link = (reg >> 8) & 0x03;
136
137 alloc_pci_root_info(bus_min: min_bus, bus_max: max_bus, node, link);
138 }
139
140 /*
141 * The following code extracts routing information for use on old
142 * systems where Linux doesn't automatically use host bridge _CRS
143 * methods (or when the user specifies "pci=nocrs").
144 *
145 * We only do this through Fam11h, because _CRS should be enough on
146 * newer systems.
147 */
148 if (boot_cpu_data.x86 > 0x11)
149 return 0;
150
151 /* get the default node and link for left over res */
152 reg = read_pci_config(bus, slot, func: 0, AMD_NB_F0_NODE_ID);
153 def_node = (reg >> 8) & 0x07;
154 reg = read_pci_config(bus, slot, func: 0, AMD_NB_F0_UNIT_ID);
155 def_link = (reg >> 8) & 0x03;
156
157 memset(range, 0, sizeof(range));
158 add_range(range, RANGE_NUM, nr_range: 0, start: 0, end: 0xffff + 1);
159 /* io port resource */
160 for (i = 0; i < 4; i++) {
161 reg = read_pci_config(bus, slot, func: 1, offset: 0xc0 + (i << 3));
162 if (!(reg & 3))
163 continue;
164
165 start = reg & 0xfff000;
166 reg = read_pci_config(bus, slot, func: 1, offset: 0xc4 + (i << 3));
167 node = reg & 0x07;
168 link = (reg >> 4) & 0x03;
169 end = (reg & 0xfff000) | 0xfff;
170
171 info = find_pci_root_info(node, link);
172 if (!info)
173 continue; /* not found */
174
175 printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
176 node, link, start, end);
177
178 /* kernel only handle 16 bit only */
179 if (end > 0xffff)
180 end = 0xffff;
181 update_res(info, start, end, IORESOURCE_IO, merge: 1);
182 subtract_range(range, RANGE_NUM, start, end: end + 1);
183 }
184 /* add left over io port range to def node/link, [0, 0xffff] */
185 /* find the position */
186 info = find_pci_root_info(node: def_node, link: def_link);
187 if (info) {
188 for (i = 0; i < RANGE_NUM; i++) {
189 if (!range[i].end)
190 continue;
191
192 update_res(info, start: range[i].start, end: range[i].end - 1,
193 IORESOURCE_IO, merge: 1);
194 }
195 }
196
197 memset(range, 0, sizeof(range));
198 /* 0xfd00000000-0xffffffffff for HT */
199 end = cap_resource(val: (0xfdULL<<32) - 1);
200 end++;
201 add_range(range, RANGE_NUM, nr_range: 0, start: 0, end);
202
203 /* need to take out [0, TOM) for RAM*/
204 address = MSR_K8_TOP_MEM1;
205 rdmsrl(address, val);
206 end = (val & 0xffffff800000ULL);
207 printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
208 if (end < (1ULL<<32))
209 subtract_range(range, RANGE_NUM, start: 0, end);
210
211 /* get mmconfig */
212 fam10h_mmconf = amd_get_mmconfig_range(res: &fam10h_mmconf_res);
213 /* need to take out mmconf range */
214 if (fam10h_mmconf) {
215 printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
216 fam10h_mmconf_start = fam10h_mmconf->start;
217 fam10h_mmconf_end = fam10h_mmconf->end;
218 subtract_range(range, RANGE_NUM, start: fam10h_mmconf_start,
219 end: fam10h_mmconf_end + 1);
220 } else {
221 fam10h_mmconf_start = 0;
222 fam10h_mmconf_end = 0;
223 }
224
225 /* mmio resource */
226 for (i = 0; i < 8; i++) {
227 reg = read_pci_config(bus, slot, func: 1, offset: 0x80 + (i << 3));
228 if (!(reg & 3))
229 continue;
230
231 start = reg & 0xffffff00; /* 39:16 on 31:8*/
232 start <<= 8;
233 reg = read_pci_config(bus, slot, func: 1, offset: 0x84 + (i << 3));
234 node = reg & 0x07;
235 link = (reg >> 4) & 0x03;
236 end = (reg & 0xffffff00);
237 end <<= 8;
238 end |= 0xffff;
239
240 info = find_pci_root_info(node, link);
241
242 if (!info)
243 continue;
244
245 printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
246 node, link, start, end);
247 /*
248 * some sick allocation would have range overlap with fam10h
249 * mmconf range, so need to update start and end.
250 */
251 if (fam10h_mmconf_end) {
252 int changed = 0;
253 u64 endx = 0;
254 if (start >= fam10h_mmconf_start &&
255 start <= fam10h_mmconf_end) {
256 start = fam10h_mmconf_end + 1;
257 changed = 1;
258 }
259
260 if (end >= fam10h_mmconf_start &&
261 end <= fam10h_mmconf_end) {
262 end = fam10h_mmconf_start - 1;
263 changed = 1;
264 }
265
266 if (start < fam10h_mmconf_start &&
267 end > fam10h_mmconf_end) {
268 /* we got a hole */
269 endx = fam10h_mmconf_start - 1;
270 update_res(info, start, end: endx, IORESOURCE_MEM, merge: 0);
271 subtract_range(range, RANGE_NUM, start,
272 end: endx + 1);
273 printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
274 start = fam10h_mmconf_end + 1;
275 changed = 1;
276 }
277 if (changed) {
278 if (start <= end) {
279 printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
280 } else {
281 printk(KERN_CONT "%s\n", endx?"":" ==> none");
282 continue;
283 }
284 }
285 }
286
287 update_res(info, start: cap_resource(val: start), end: cap_resource(val: end),
288 IORESOURCE_MEM, merge: 1);
289 subtract_range(range, RANGE_NUM, start, end: end + 1);
290 printk(KERN_CONT "\n");
291 }
292
293 /* need to take out [4G, TOM2) for RAM*/
294 /* SYS_CFG */
295 address = MSR_AMD64_SYSCFG;
296 rdmsrl(address, val);
297 /* TOP_MEM2 is enabled? */
298 if (val & (1<<21)) {
299 /* TOP_MEM2 */
300 address = MSR_K8_TOP_MEM2;
301 rdmsrl(address, val);
302 end = (val & 0xffffff800000ULL);
303 printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
304 subtract_range(range, RANGE_NUM, start: 1ULL<<32, end);
305 }
306
307 /*
308 * add left over mmio range to def node/link ?
309 * that is tricky, just record range in from start_min to 4G
310 */
311 info = find_pci_root_info(node: def_node, link: def_link);
312 if (info) {
313 for (i = 0; i < RANGE_NUM; i++) {
314 if (!range[i].end)
315 continue;
316
317 update_res(info, start: cap_resource(val: range[i].start),
318 end: cap_resource(val: range[i].end - 1),
319 IORESOURCE_MEM, merge: 1);
320 }
321 }
322
323 list_for_each_entry(info, &pci_root_infos, list) {
324 int busnum;
325 struct pci_root_res *root_res;
326
327 busnum = info->busn.start;
328 printk(KERN_DEBUG "bus: %pR on node %x link %x\n",
329 &info->busn, info->node, info->link);
330 list_for_each_entry(root_res, &info->resources, list)
331 printk(KERN_DEBUG "bus: %02x %pR\n",
332 busnum, &root_res->res);
333 }
334
335 return 0;
336}
337
338#define ENABLE_CF8_EXT_CFG (1ULL << 46)
339
340static int amd_bus_cpu_online(unsigned int cpu)
341{
342 u64 reg;
343
344 rdmsrl(MSR_AMD64_NB_CFG, reg);
345 if (!(reg & ENABLE_CF8_EXT_CFG)) {
346 reg |= ENABLE_CF8_EXT_CFG;
347 wrmsrl(MSR_AMD64_NB_CFG, val: reg);
348 }
349 return 0;
350}
351
352static void __init pci_enable_pci_io_ecs(void)
353{
354#ifdef CONFIG_AMD_NB
355 unsigned int i, n;
356
357 for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
358 u8 bus = amd_nb_bus_dev_ranges[i].bus;
359 u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
360 u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
361
362 for (; slot < limit; ++slot) {
363 u32 val = read_pci_config(bus, slot, func: 3, offset: 0);
364
365 if (!early_is_amd_nb(value: val))
366 continue;
367
368 val = read_pci_config(bus, slot, func: 3, offset: 0x8c);
369 if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
370 val |= ENABLE_CF8_EXT_CFG >> 32;
371 write_pci_config(bus, slot, func: 3, offset: 0x8c, val);
372 }
373 ++n;
374 }
375 }
376#endif
377}
378
379static int __init pci_io_ecs_init(void)
380{
381 int ret;
382
383 /* assume all cpus from fam10h have IO ECS */
384 if (boot_cpu_data.x86 < 0x10)
385 return 0;
386
387 /* Try the PCI method first. */
388 if (early_pci_allowed())
389 pci_enable_pci_io_ecs();
390
391 ret = cpuhp_setup_state(state: CPUHP_AP_ONLINE_DYN, name: "pci/amd_bus:online",
392 startup: amd_bus_cpu_online, NULL);
393 WARN_ON(ret < 0);
394
395 pci_probe |= PCI_HAS_IO_ECS;
396
397 return 0;
398}
399
400static int __init amd_postcore_init(void)
401{
402 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
403 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
404 return 0;
405
406 early_root_info_init();
407 pci_io_ecs_init();
408
409 return 0;
410}
411
412postcore_initcall(amd_postcore_init);
413

source code of linux/arch/x86/pci/amd_bus.c