xref: /openbmc/linux/arch/x86/pci/amd_bus.c (revision dea54fba)
1 #include <linux/init.h>
2 #include <linux/pci.h>
3 #include <linux/topology.h>
4 #include <linux/cpu.h>
5 #include <linux/range.h>
6 
7 #include <asm/amd_nb.h>
8 #include <asm/pci_x86.h>
9 
10 #include <asm/pci-direct.h>
11 
12 #include "bus_numa.h"
13 
14 #define AMD_NB_F0_NODE_ID			0x60
15 #define AMD_NB_F0_UNIT_ID			0x64
16 #define AMD_NB_F1_CONFIG_MAP_REG		0xe0
17 
18 #define RANGE_NUM				16
19 #define AMD_NB_F1_CONFIG_MAP_RANGES		4
20 
21 struct amd_hostbridge {
22 	u32 bus;
23 	u32 slot;
24 	u32 device;
25 };
26 
27 /*
28  * IMPORTANT NOTE:
29  * hb_probes[] and early_root_info_init() is in maintenance mode.
30  * It only supports K8, Fam10h, Fam11h, and Fam15h_00h-0fh .
31  * Future processor will rely on information in ACPI.
32  */
33 static struct amd_hostbridge hb_probes[] __initdata = {
34 	{ 0, 0x18, 0x1100 }, /* K8 */
35 	{ 0, 0x18, 0x1200 }, /* Family10h */
36 	{ 0xff, 0, 0x1200 }, /* Family10h */
37 	{ 0, 0x18, 0x1300 }, /* Family11h */
38 	{ 0, 0x18, 0x1600 }, /* Family15h */
39 };
40 
41 static struct pci_root_info __init *find_pci_root_info(int node, int link)
42 {
43 	struct pci_root_info *info;
44 
45 	/* find the position */
46 	list_for_each_entry(info, &pci_root_infos, list)
47 		if (info->node == node && info->link == link)
48 			return info;
49 
50 	return NULL;
51 }
52 
53 /**
54  * early_root_info_init()
55  * called before pcibios_scan_root and pci_scan_bus
56  * fills the mp_bus_to_cpumask array based according
57  * to the LDT Bus Number Registers found in the northbridge.
58  */
59 static int __init early_root_info_init(void)
60 {
61 	int i;
62 	unsigned bus;
63 	unsigned slot;
64 	int node;
65 	int link;
66 	int def_node;
67 	int def_link;
68 	struct pci_root_info *info;
69 	u32 reg;
70 	u64 start;
71 	u64 end;
72 	struct range range[RANGE_NUM];
73 	u64 val;
74 	u32 address;
75 	bool found;
76 	struct resource fam10h_mmconf_res, *fam10h_mmconf;
77 	u64 fam10h_mmconf_start;
78 	u64 fam10h_mmconf_end;
79 
80 	if (!early_pci_allowed())
81 		return -1;
82 
83 	found = false;
84 	for (i = 0; i < ARRAY_SIZE(hb_probes); i++) {
85 		u32 id;
86 		u16 device;
87 		u16 vendor;
88 
89 		bus = hb_probes[i].bus;
90 		slot = hb_probes[i].slot;
91 		id = read_pci_config(bus, slot, 0, PCI_VENDOR_ID);
92 		vendor = id & 0xffff;
93 		device = (id>>16) & 0xffff;
94 
95 		if (vendor != PCI_VENDOR_ID_AMD)
96 			continue;
97 
98 		if (hb_probes[i].device == device) {
99 			found = true;
100 			break;
101 		}
102 	}
103 
104 	if (!found)
105 		return 0;
106 
107 	/*
108 	 * We should learn topology and routing information from _PXM and
109 	 * _CRS methods in the ACPI namespace.  We extract node numbers
110 	 * here to work around BIOSes that don't supply _PXM.
111 	 */
112 	for (i = 0; i < AMD_NB_F1_CONFIG_MAP_RANGES; i++) {
113 		int min_bus;
114 		int max_bus;
115 		reg = read_pci_config(bus, slot, 1,
116 				AMD_NB_F1_CONFIG_MAP_REG + (i << 2));
117 
118 		/* Check if that register is enabled for bus range */
119 		if ((reg & 7) != 3)
120 			continue;
121 
122 		min_bus = (reg >> 16) & 0xff;
123 		max_bus = (reg >> 24) & 0xff;
124 		node = (reg >> 4) & 0x07;
125 		link = (reg >> 8) & 0x03;
126 
127 		info = alloc_pci_root_info(min_bus, max_bus, node, link);
128 	}
129 
130 	/*
131 	 * The following code extracts routing information for use on old
132 	 * systems where Linux doesn't automatically use host bridge _CRS
133 	 * methods (or when the user specifies "pci=nocrs").
134 	 *
135 	 * We only do this through Fam11h, because _CRS should be enough on
136 	 * newer systems.
137 	 */
138 	if (boot_cpu_data.x86 > 0x11)
139 		return 0;
140 
141 	/* get the default node and link for left over res */
142 	reg = read_pci_config(bus, slot, 0, AMD_NB_F0_NODE_ID);
143 	def_node = (reg >> 8) & 0x07;
144 	reg = read_pci_config(bus, slot, 0, AMD_NB_F0_UNIT_ID);
145 	def_link = (reg >> 8) & 0x03;
146 
147 	memset(range, 0, sizeof(range));
148 	add_range(range, RANGE_NUM, 0, 0, 0xffff + 1);
149 	/* io port resource */
150 	for (i = 0; i < 4; i++) {
151 		reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
152 		if (!(reg & 3))
153 			continue;
154 
155 		start = reg & 0xfff000;
156 		reg = read_pci_config(bus, slot, 1, 0xc4 + (i << 3));
157 		node = reg & 0x07;
158 		link = (reg >> 4) & 0x03;
159 		end = (reg & 0xfff000) | 0xfff;
160 
161 		info = find_pci_root_info(node, link);
162 		if (!info)
163 			continue; /* not found */
164 
165 		printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
166 		       node, link, start, end);
167 
168 		/* kernel only handle 16 bit only */
169 		if (end > 0xffff)
170 			end = 0xffff;
171 		update_res(info, start, end, IORESOURCE_IO, 1);
172 		subtract_range(range, RANGE_NUM, start, end + 1);
173 	}
174 	/* add left over io port range to def node/link, [0, 0xffff] */
175 	/* find the position */
176 	info = find_pci_root_info(def_node, def_link);
177 	if (info) {
178 		for (i = 0; i < RANGE_NUM; i++) {
179 			if (!range[i].end)
180 				continue;
181 
182 			update_res(info, range[i].start, range[i].end - 1,
183 				   IORESOURCE_IO, 1);
184 		}
185 	}
186 
187 	memset(range, 0, sizeof(range));
188 	/* 0xfd00000000-0xffffffffff for HT */
189 	end = cap_resource((0xfdULL<<32) - 1);
190 	end++;
191 	add_range(range, RANGE_NUM, 0, 0, end);
192 
193 	/* need to take out [0, TOM) for RAM*/
194 	address = MSR_K8_TOP_MEM1;
195 	rdmsrl(address, val);
196 	end = (val & 0xffffff800000ULL);
197 	printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
198 	if (end < (1ULL<<32))
199 		subtract_range(range, RANGE_NUM, 0, end);
200 
201 	/* get mmconfig */
202 	fam10h_mmconf = amd_get_mmconfig_range(&fam10h_mmconf_res);
203 	/* need to take out mmconf range */
204 	if (fam10h_mmconf) {
205 		printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
206 		fam10h_mmconf_start = fam10h_mmconf->start;
207 		fam10h_mmconf_end = fam10h_mmconf->end;
208 		subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
209 				 fam10h_mmconf_end + 1);
210 	} else {
211 		fam10h_mmconf_start = 0;
212 		fam10h_mmconf_end = 0;
213 	}
214 
215 	/* mmio resource */
216 	for (i = 0; i < 8; i++) {
217 		reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
218 		if (!(reg & 3))
219 			continue;
220 
221 		start = reg & 0xffffff00; /* 39:16 on 31:8*/
222 		start <<= 8;
223 		reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
224 		node = reg & 0x07;
225 		link = (reg >> 4) & 0x03;
226 		end = (reg & 0xffffff00);
227 		end <<= 8;
228 		end |= 0xffff;
229 
230 		info = find_pci_root_info(node, link);
231 
232 		if (!info)
233 			continue;
234 
235 		printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
236 		       node, link, start, end);
237 		/*
238 		 * some sick allocation would have range overlap with fam10h
239 		 * mmconf range, so need to update start and end.
240 		 */
241 		if (fam10h_mmconf_end) {
242 			int changed = 0;
243 			u64 endx = 0;
244 			if (start >= fam10h_mmconf_start &&
245 			    start <= fam10h_mmconf_end) {
246 				start = fam10h_mmconf_end + 1;
247 				changed = 1;
248 			}
249 
250 			if (end >= fam10h_mmconf_start &&
251 			    end <= fam10h_mmconf_end) {
252 				end = fam10h_mmconf_start - 1;
253 				changed = 1;
254 			}
255 
256 			if (start < fam10h_mmconf_start &&
257 			    end > fam10h_mmconf_end) {
258 				/* we got a hole */
259 				endx = fam10h_mmconf_start - 1;
260 				update_res(info, start, endx, IORESOURCE_MEM, 0);
261 				subtract_range(range, RANGE_NUM, start,
262 						 endx + 1);
263 				printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
264 				start = fam10h_mmconf_end + 1;
265 				changed = 1;
266 			}
267 			if (changed) {
268 				if (start <= end) {
269 					printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
270 				} else {
271 					printk(KERN_CONT "%s\n", endx?"":" ==> none");
272 					continue;
273 				}
274 			}
275 		}
276 
277 		update_res(info, cap_resource(start), cap_resource(end),
278 				 IORESOURCE_MEM, 1);
279 		subtract_range(range, RANGE_NUM, start, end + 1);
280 		printk(KERN_CONT "\n");
281 	}
282 
283 	/* need to take out [4G, TOM2) for RAM*/
284 	/* SYS_CFG */
285 	address = MSR_K8_SYSCFG;
286 	rdmsrl(address, val);
287 	/* TOP_MEM2 is enabled? */
288 	if (val & (1<<21)) {
289 		/* TOP_MEM2 */
290 		address = MSR_K8_TOP_MEM2;
291 		rdmsrl(address, val);
292 		end = (val & 0xffffff800000ULL);
293 		printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
294 		subtract_range(range, RANGE_NUM, 1ULL<<32, end);
295 	}
296 
297 	/*
298 	 * add left over mmio range to def node/link ?
299 	 * that is tricky, just record range in from start_min to 4G
300 	 */
301 	info = find_pci_root_info(def_node, def_link);
302 	if (info) {
303 		for (i = 0; i < RANGE_NUM; i++) {
304 			if (!range[i].end)
305 				continue;
306 
307 			update_res(info, cap_resource(range[i].start),
308 				   cap_resource(range[i].end - 1),
309 				   IORESOURCE_MEM, 1);
310 		}
311 	}
312 
313 	list_for_each_entry(info, &pci_root_infos, list) {
314 		int busnum;
315 		struct pci_root_res *root_res;
316 
317 		busnum = info->busn.start;
318 		printk(KERN_DEBUG "bus: %pR on node %x link %x\n",
319 		       &info->busn, info->node, info->link);
320 		list_for_each_entry(root_res, &info->resources, list)
321 			printk(KERN_DEBUG "bus: %02x %pR\n",
322 				       busnum, &root_res->res);
323 	}
324 
325 	return 0;
326 }
327 
328 #define ENABLE_CF8_EXT_CFG      (1ULL << 46)
329 
330 static int amd_bus_cpu_online(unsigned int cpu)
331 {
332 	u64 reg;
333 
334 	rdmsrl(MSR_AMD64_NB_CFG, reg);
335 	if (!(reg & ENABLE_CF8_EXT_CFG)) {
336 		reg |= ENABLE_CF8_EXT_CFG;
337 		wrmsrl(MSR_AMD64_NB_CFG, reg);
338 	}
339 	return 0;
340 }
341 
342 static void __init pci_enable_pci_io_ecs(void)
343 {
344 #ifdef CONFIG_AMD_NB
345 	unsigned int i, n;
346 
347 	for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
348 		u8 bus = amd_nb_bus_dev_ranges[i].bus;
349 		u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
350 		u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
351 
352 		for (; slot < limit; ++slot) {
353 			u32 val = read_pci_config(bus, slot, 3, 0);
354 
355 			if (!early_is_amd_nb(val))
356 				continue;
357 
358 			val = read_pci_config(bus, slot, 3, 0x8c);
359 			if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
360 				val |= ENABLE_CF8_EXT_CFG >> 32;
361 				write_pci_config(bus, slot, 3, 0x8c, val);
362 			}
363 			++n;
364 		}
365 	}
366 #endif
367 }
368 
369 static int __init pci_io_ecs_init(void)
370 {
371 	int ret;
372 
373 	/* assume all cpus from fam10h have IO ECS */
374 	if (boot_cpu_data.x86 < 0x10)
375 		return 0;
376 
377 	/* Try the PCI method first. */
378 	if (early_pci_allowed())
379 		pci_enable_pci_io_ecs();
380 
381 	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "pci/amd_bus:online",
382 				amd_bus_cpu_online, NULL);
383 	WARN_ON(ret < 0);
384 
385 	pci_probe |= PCI_HAS_IO_ECS;
386 
387 	return 0;
388 }
389 
390 static int __init amd_postcore_init(void)
391 {
392 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
393 		return 0;
394 
395 	early_root_info_init();
396 	pci_io_ecs_init();
397 
398 	return 0;
399 }
400 
401 postcore_initcall(amd_postcore_init);
402