xref: /openbmc/linux/arch/x86/pci/amd_bus.c (revision feac8c8b)
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 			continue;
98 
99 		if (hb_probes[i].device == device) {
100 			found = true;
101 			break;
102 		}
103 	}
104 
105 	if (!found)
106 		return 0;
107 
108 	/*
109 	 * We should learn topology and routing information from _PXM and
110 	 * _CRS methods in the ACPI namespace.  We extract node numbers
111 	 * here to work around BIOSes that don't supply _PXM.
112 	 */
113 	for (i = 0; i < AMD_NB_F1_CONFIG_MAP_RANGES; i++) {
114 		int min_bus;
115 		int max_bus;
116 		reg = read_pci_config(bus, slot, 1,
117 				AMD_NB_F1_CONFIG_MAP_REG + (i << 2));
118 
119 		/* Check if that register is enabled for bus range */
120 		if ((reg & 7) != 3)
121 			continue;
122 
123 		min_bus = (reg >> 16) & 0xff;
124 		max_bus = (reg >> 24) & 0xff;
125 		node = (reg >> 4) & 0x07;
126 		link = (reg >> 8) & 0x03;
127 
128 		info = alloc_pci_root_info(min_bus, max_bus, node, link);
129 	}
130 
131 	/*
132 	 * The following code extracts routing information for use on old
133 	 * systems where Linux doesn't automatically use host bridge _CRS
134 	 * methods (or when the user specifies "pci=nocrs").
135 	 *
136 	 * We only do this through Fam11h, because _CRS should be enough on
137 	 * newer systems.
138 	 */
139 	if (boot_cpu_data.x86 > 0x11)
140 		return 0;
141 
142 	/* get the default node and link for left over res */
143 	reg = read_pci_config(bus, slot, 0, AMD_NB_F0_NODE_ID);
144 	def_node = (reg >> 8) & 0x07;
145 	reg = read_pci_config(bus, slot, 0, AMD_NB_F0_UNIT_ID);
146 	def_link = (reg >> 8) & 0x03;
147 
148 	memset(range, 0, sizeof(range));
149 	add_range(range, RANGE_NUM, 0, 0, 0xffff + 1);
150 	/* io port resource */
151 	for (i = 0; i < 4; i++) {
152 		reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
153 		if (!(reg & 3))
154 			continue;
155 
156 		start = reg & 0xfff000;
157 		reg = read_pci_config(bus, slot, 1, 0xc4 + (i << 3));
158 		node = reg & 0x07;
159 		link = (reg >> 4) & 0x03;
160 		end = (reg & 0xfff000) | 0xfff;
161 
162 		info = find_pci_root_info(node, link);
163 		if (!info)
164 			continue; /* not found */
165 
166 		printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
167 		       node, link, start, end);
168 
169 		/* kernel only handle 16 bit only */
170 		if (end > 0xffff)
171 			end = 0xffff;
172 		update_res(info, start, end, IORESOURCE_IO, 1);
173 		subtract_range(range, RANGE_NUM, start, end + 1);
174 	}
175 	/* add left over io port range to def node/link, [0, 0xffff] */
176 	/* find the position */
177 	info = find_pci_root_info(def_node, def_link);
178 	if (info) {
179 		for (i = 0; i < RANGE_NUM; i++) {
180 			if (!range[i].end)
181 				continue;
182 
183 			update_res(info, range[i].start, range[i].end - 1,
184 				   IORESOURCE_IO, 1);
185 		}
186 	}
187 
188 	memset(range, 0, sizeof(range));
189 	/* 0xfd00000000-0xffffffffff for HT */
190 	end = cap_resource((0xfdULL<<32) - 1);
191 	end++;
192 	add_range(range, RANGE_NUM, 0, 0, end);
193 
194 	/* need to take out [0, TOM) for RAM*/
195 	address = MSR_K8_TOP_MEM1;
196 	rdmsrl(address, val);
197 	end = (val & 0xffffff800000ULL);
198 	printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
199 	if (end < (1ULL<<32))
200 		subtract_range(range, RANGE_NUM, 0, end);
201 
202 	/* get mmconfig */
203 	fam10h_mmconf = amd_get_mmconfig_range(&fam10h_mmconf_res);
204 	/* need to take out mmconf range */
205 	if (fam10h_mmconf) {
206 		printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
207 		fam10h_mmconf_start = fam10h_mmconf->start;
208 		fam10h_mmconf_end = fam10h_mmconf->end;
209 		subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
210 				 fam10h_mmconf_end + 1);
211 	} else {
212 		fam10h_mmconf_start = 0;
213 		fam10h_mmconf_end = 0;
214 	}
215 
216 	/* mmio resource */
217 	for (i = 0; i < 8; i++) {
218 		reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
219 		if (!(reg & 3))
220 			continue;
221 
222 		start = reg & 0xffffff00; /* 39:16 on 31:8*/
223 		start <<= 8;
224 		reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
225 		node = reg & 0x07;
226 		link = (reg >> 4) & 0x03;
227 		end = (reg & 0xffffff00);
228 		end <<= 8;
229 		end |= 0xffff;
230 
231 		info = find_pci_root_info(node, link);
232 
233 		if (!info)
234 			continue;
235 
236 		printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
237 		       node, link, start, end);
238 		/*
239 		 * some sick allocation would have range overlap with fam10h
240 		 * mmconf range, so need to update start and end.
241 		 */
242 		if (fam10h_mmconf_end) {
243 			int changed = 0;
244 			u64 endx = 0;
245 			if (start >= fam10h_mmconf_start &&
246 			    start <= fam10h_mmconf_end) {
247 				start = fam10h_mmconf_end + 1;
248 				changed = 1;
249 			}
250 
251 			if (end >= fam10h_mmconf_start &&
252 			    end <= fam10h_mmconf_end) {
253 				end = fam10h_mmconf_start - 1;
254 				changed = 1;
255 			}
256 
257 			if (start < fam10h_mmconf_start &&
258 			    end > fam10h_mmconf_end) {
259 				/* we got a hole */
260 				endx = fam10h_mmconf_start - 1;
261 				update_res(info, start, endx, IORESOURCE_MEM, 0);
262 				subtract_range(range, RANGE_NUM, start,
263 						 endx + 1);
264 				printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
265 				start = fam10h_mmconf_end + 1;
266 				changed = 1;
267 			}
268 			if (changed) {
269 				if (start <= end) {
270 					printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
271 				} else {
272 					printk(KERN_CONT "%s\n", endx?"":" ==> none");
273 					continue;
274 				}
275 			}
276 		}
277 
278 		update_res(info, cap_resource(start), cap_resource(end),
279 				 IORESOURCE_MEM, 1);
280 		subtract_range(range, RANGE_NUM, start, end + 1);
281 		printk(KERN_CONT "\n");
282 	}
283 
284 	/* need to take out [4G, TOM2) for RAM*/
285 	/* SYS_CFG */
286 	address = MSR_K8_SYSCFG;
287 	rdmsrl(address, val);
288 	/* TOP_MEM2 is enabled? */
289 	if (val & (1<<21)) {
290 		/* TOP_MEM2 */
291 		address = MSR_K8_TOP_MEM2;
292 		rdmsrl(address, val);
293 		end = (val & 0xffffff800000ULL);
294 		printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
295 		subtract_range(range, RANGE_NUM, 1ULL<<32, end);
296 	}
297 
298 	/*
299 	 * add left over mmio range to def node/link ?
300 	 * that is tricky, just record range in from start_min to 4G
301 	 */
302 	info = find_pci_root_info(def_node, def_link);
303 	if (info) {
304 		for (i = 0; i < RANGE_NUM; i++) {
305 			if (!range[i].end)
306 				continue;
307 
308 			update_res(info, cap_resource(range[i].start),
309 				   cap_resource(range[i].end - 1),
310 				   IORESOURCE_MEM, 1);
311 		}
312 	}
313 
314 	list_for_each_entry(info, &pci_root_infos, list) {
315 		int busnum;
316 		struct pci_root_res *root_res;
317 
318 		busnum = info->busn.start;
319 		printk(KERN_DEBUG "bus: %pR on node %x link %x\n",
320 		       &info->busn, info->node, info->link);
321 		list_for_each_entry(root_res, &info->resources, list)
322 			printk(KERN_DEBUG "bus: %02x %pR\n",
323 				       busnum, &root_res->res);
324 	}
325 
326 	return 0;
327 }
328 
329 #define ENABLE_CF8_EXT_CFG      (1ULL << 46)
330 
331 static int amd_bus_cpu_online(unsigned int cpu)
332 {
333 	u64 reg;
334 
335 	rdmsrl(MSR_AMD64_NB_CFG, reg);
336 	if (!(reg & ENABLE_CF8_EXT_CFG)) {
337 		reg |= ENABLE_CF8_EXT_CFG;
338 		wrmsrl(MSR_AMD64_NB_CFG, reg);
339 	}
340 	return 0;
341 }
342 
343 static void __init pci_enable_pci_io_ecs(void)
344 {
345 #ifdef CONFIG_AMD_NB
346 	unsigned int i, n;
347 
348 	for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
349 		u8 bus = amd_nb_bus_dev_ranges[i].bus;
350 		u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
351 		u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
352 
353 		for (; slot < limit; ++slot) {
354 			u32 val = read_pci_config(bus, slot, 3, 0);
355 
356 			if (!early_is_amd_nb(val))
357 				continue;
358 
359 			val = read_pci_config(bus, slot, 3, 0x8c);
360 			if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
361 				val |= ENABLE_CF8_EXT_CFG >> 32;
362 				write_pci_config(bus, slot, 3, 0x8c, val);
363 			}
364 			++n;
365 		}
366 	}
367 #endif
368 }
369 
370 static int __init pci_io_ecs_init(void)
371 {
372 	int ret;
373 
374 	/* assume all cpus from fam10h have IO ECS */
375 	if (boot_cpu_data.x86 < 0x10)
376 		return 0;
377 
378 	/* Try the PCI method first. */
379 	if (early_pci_allowed())
380 		pci_enable_pci_io_ecs();
381 
382 	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "pci/amd_bus:online",
383 				amd_bus_cpu_online, NULL);
384 	WARN_ON(ret < 0);
385 
386 	pci_probe |= PCI_HAS_IO_ECS;
387 
388 	return 0;
389 }
390 
391 static int __init amd_postcore_init(void)
392 {
393 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
394 		return 0;
395 
396 	early_root_info_init();
397 	pci_io_ecs_init();
398 
399 	return 0;
400 }
401 
402 postcore_initcall(amd_postcore_init);
403