xref: /linux/arch/x86/pci/amd_bus.c (revision a1c613ae4c322ddd58d5a8539dbfba2a0380a8c0)
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 
find_pci_root_info(int node,int link)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 
cap_resource(u64 val)54 static 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  */
early_root_info_init(void)68 static 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, 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, 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(min_bus, 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, 0, AMD_NB_F0_NODE_ID);
153 	def_node = (reg >> 8) & 0x07;
154 	reg = read_pci_config(bus, slot, 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, 0, 0, 0xffff + 1);
159 	/* io port resource */
160 	for (i = 0; i < 4; i++) {
161 		reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
162 		if (!(reg & 3))
163 			continue;
164 
165 		start = reg & 0xfff000;
166 		reg = read_pci_config(bus, slot, 1, 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, 1);
182 		subtract_range(range, RANGE_NUM, start, 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(def_node, 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, range[i].start, range[i].end - 1,
193 				   IORESOURCE_IO, 1);
194 		}
195 	}
196 
197 	memset(range, 0, sizeof(range));
198 	/* 0xfd00000000-0xffffffffff for HT */
199 	end = cap_resource((0xfdULL<<32) - 1);
200 	end++;
201 	add_range(range, RANGE_NUM, 0, 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, 0, end);
210 
211 	/* get mmconfig */
212 	fam10h_mmconf = amd_get_mmconfig_range(&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, fam10h_mmconf_start,
219 				 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, 1, 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, 1, 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, endx, IORESOURCE_MEM, 0);
271 				subtract_range(range, RANGE_NUM, start,
272 						 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, cap_resource(start), cap_resource(end),
288 				 IORESOURCE_MEM, 1);
289 		subtract_range(range, RANGE_NUM, start, 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, 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(def_node, 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, cap_resource(range[i].start),
318 				   cap_resource(range[i].end - 1),
319 				   IORESOURCE_MEM, 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 
amd_bus_cpu_online(unsigned int cpu)340 static 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, reg);
348 	}
349 	return 0;
350 }
351 
pci_enable_pci_io_ecs(void)352 static 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, 3, 0);
364 
365 			if (!early_is_amd_nb(val))
366 				continue;
367 
368 			val = read_pci_config(bus, slot, 3, 0x8c);
369 			if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
370 				val |= ENABLE_CF8_EXT_CFG >> 32;
371 				write_pci_config(bus, slot, 3, 0x8c, val);
372 			}
373 			++n;
374 		}
375 	}
376 #endif
377 }
378 
pci_io_ecs_init(void)379 static 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(CPUHP_AP_ONLINE_DYN, "pci/amd_bus:online",
392 				amd_bus_cpu_online, NULL);
393 	WARN_ON(ret < 0);
394 
395 	pci_probe |= PCI_HAS_IO_ECS;
396 
397 	return 0;
398 }
399 
amd_postcore_init(void)400 static 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 
412 postcore_initcall(amd_postcore_init);
413