1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Shared support code for AMD K8 northbridges and derivatives.
4 * Copyright 2006 Andi Kleen, SUSE Labs.
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <linux/types.h>
10#include <linux/slab.h>
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <linux/export.h>
14#include <linux/spinlock.h>
15#include <linux/pci_ids.h>
16
17#include <asm/amd/nb.h>
18#include <asm/cpuid/api.h>
19
20static u32 *flush_words;
21
22static const struct pci_device_id amd_nb_misc_ids[] = {
23 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
24 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
25 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
26 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
27 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
28 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
29 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
30 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
31 {}
32};
33
34const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
35 { 0x00, 0x18, 0x20 },
36 { 0xff, 0x00, 0x20 },
37 { 0xfe, 0x00, 0x20 },
38 { }
39};
40
41static struct amd_northbridge_info amd_northbridges;
42
43u16 amd_nb_num(void)
44{
45 return amd_northbridges.num;
46}
47EXPORT_SYMBOL_GPL(amd_nb_num);
48
49bool amd_nb_has_feature(unsigned int feature)
50{
51 return ((amd_northbridges.flags & feature) == feature);
52}
53EXPORT_SYMBOL_GPL(amd_nb_has_feature);
54
55struct amd_northbridge *node_to_amd_nb(int node)
56{
57 return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
58}
59EXPORT_SYMBOL_GPL(node_to_amd_nb);
60
61static int amd_cache_northbridges(void)
62{
63 struct amd_northbridge *nb;
64 u16 i;
65
66 if (amd_northbridges.num)
67 return 0;
68
69 amd_northbridges.num = amd_num_nodes();
70
71 nb = kcalloc(amd_northbridges.num, sizeof(struct amd_northbridge), GFP_KERNEL);
72 if (!nb)
73 return -ENOMEM;
74
75 amd_northbridges.nb = nb;
76
77 for (i = 0; i < amd_northbridges.num; i++) {
78 node_to_amd_nb(i)->misc = amd_node_get_func(node: i, func: 3);
79
80 /*
81 * Each Northbridge must have a 'misc' device.
82 * If not, then uninitialize everything.
83 */
84 if (!node_to_amd_nb(i)->misc) {
85 amd_northbridges.num = 0;
86 kfree(objp: nb);
87 return -ENODEV;
88 }
89
90 node_to_amd_nb(i)->link = amd_node_get_func(node: i, func: 4);
91 }
92
93 if (amd_gart_present())
94 amd_northbridges.flags |= AMD_NB_GART;
95
96 if (!cpuid_amd_hygon_has_l3_cache())
97 return 0;
98
99 /*
100 * Some CPU families support L3 Cache Index Disable. There are some
101 * limitations because of E382 and E388 on family 0x10.
102 */
103 if (boot_cpu_data.x86 == 0x10 &&
104 boot_cpu_data.x86_model >= 0x8 &&
105 (boot_cpu_data.x86_model > 0x9 ||
106 boot_cpu_data.x86_stepping >= 0x1))
107 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
108
109 if (boot_cpu_data.x86 == 0x15)
110 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
111
112 /* L3 cache partitioning is supported on family 0x15 */
113 if (boot_cpu_data.x86 == 0x15)
114 amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
115
116 return 0;
117}
118
119/*
120 * Ignores subdevice/subvendor but as far as I can figure out
121 * they're useless anyways
122 */
123bool __init early_is_amd_nb(u32 device)
124{
125 const struct pci_device_id *id;
126 u32 vendor = device & 0xffff;
127
128 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
129 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
130 return false;
131
132 if (cpu_feature_enabled(X86_FEATURE_ZEN))
133 return false;
134
135 device >>= 16;
136 for (id = amd_nb_misc_ids; id->vendor; id++)
137 if (vendor == id->vendor && device == id->device)
138 return true;
139 return false;
140}
141
142struct resource *amd_get_mmconfig_range(struct resource *res)
143{
144 u64 base, msr;
145 unsigned int segn_busn_bits;
146
147 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
148 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
149 return NULL;
150
151 /* Assume CPUs from Fam10h have mmconfig, although not all VMs do */
152 if (boot_cpu_data.x86 < 0x10 ||
153 rdmsrq_safe(MSR_FAM10H_MMIO_CONF_BASE, p: &msr))
154 return NULL;
155
156 /* mmconfig is not enabled */
157 if (!(msr & FAM10H_MMIO_CONF_ENABLE))
158 return NULL;
159
160 base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
161
162 segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
163 FAM10H_MMIO_CONF_BUSRANGE_MASK;
164
165 res->flags = IORESOURCE_MEM;
166 res->start = base;
167 res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
168 return res;
169}
170
171int amd_get_subcaches(int cpu)
172{
173 struct pci_dev *link = node_to_amd_nb(topology_amd_node_id(cpu))->link;
174 unsigned int mask;
175
176 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
177 return 0;
178
179 pci_read_config_dword(dev: link, where: 0x1d4, val: &mask);
180
181 return (mask >> (4 * cpu_data(cpu).topo.core_id)) & 0xf;
182}
183
184int amd_set_subcaches(int cpu, unsigned long mask)
185{
186 static unsigned int reset, ban;
187 struct amd_northbridge *nb = node_to_amd_nb(topology_amd_node_id(cpu));
188 unsigned int reg;
189 int cuid;
190
191 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
192 return -EINVAL;
193
194 /* if necessary, collect reset state of L3 partitioning and BAN mode */
195 if (reset == 0) {
196 pci_read_config_dword(dev: nb->link, where: 0x1d4, val: &reset);
197 pci_read_config_dword(dev: nb->misc, where: 0x1b8, val: &ban);
198 ban &= 0x180000;
199 }
200
201 /* deactivate BAN mode if any subcaches are to be disabled */
202 if (mask != 0xf) {
203 pci_read_config_dword(dev: nb->misc, where: 0x1b8, val: &reg);
204 pci_write_config_dword(dev: nb->misc, where: 0x1b8, val: reg & ~0x180000);
205 }
206
207 cuid = cpu_data(cpu).topo.core_id;
208 mask <<= 4 * cuid;
209 mask |= (0xf ^ (1 << cuid)) << 26;
210
211 pci_write_config_dword(dev: nb->link, where: 0x1d4, val: mask);
212
213 /* reset BAN mode if L3 partitioning returned to reset state */
214 pci_read_config_dword(dev: nb->link, where: 0x1d4, val: &reg);
215 if (reg == reset) {
216 pci_read_config_dword(dev: nb->misc, where: 0x1b8, val: &reg);
217 reg &= ~0x180000;
218 pci_write_config_dword(dev: nb->misc, where: 0x1b8, val: reg | ban);
219 }
220
221 return 0;
222}
223
224static void amd_cache_gart(void)
225{
226 u16 i;
227
228 if (!amd_nb_has_feature(AMD_NB_GART))
229 return;
230
231 flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
232 if (!flush_words) {
233 amd_northbridges.flags &= ~AMD_NB_GART;
234 pr_notice("Cannot initialize GART flush words, GART support disabled\n");
235 return;
236 }
237
238 for (i = 0; i != amd_northbridges.num; i++)
239 pci_read_config_dword(dev: node_to_amd_nb(i)->misc, where: 0x9c, val: &flush_words[i]);
240}
241
242void amd_flush_garts(void)
243{
244 int flushed, i;
245 unsigned long flags;
246 static DEFINE_SPINLOCK(gart_lock);
247
248 if (!amd_nb_has_feature(AMD_NB_GART))
249 return;
250
251 /*
252 * Avoid races between AGP and IOMMU. In theory it's not needed
253 * but I'm not sure if the hardware won't lose flush requests
254 * when another is pending. This whole thing is so expensive anyways
255 * that it doesn't matter to serialize more. -AK
256 */
257 spin_lock_irqsave(&gart_lock, flags);
258 flushed = 0;
259 for (i = 0; i < amd_northbridges.num; i++) {
260 pci_write_config_dword(dev: node_to_amd_nb(i)->misc, where: 0x9c,
261 val: flush_words[i] | 1);
262 flushed++;
263 }
264 for (i = 0; i < amd_northbridges.num; i++) {
265 u32 w;
266 /* Make sure the hardware actually executed the flush*/
267 for (;;) {
268 pci_read_config_dword(dev: node_to_amd_nb(i)->misc,
269 where: 0x9c, val: &w);
270 if (!(w & 1))
271 break;
272 cpu_relax();
273 }
274 }
275 spin_unlock_irqrestore(lock: &gart_lock, flags);
276 if (!flushed)
277 pr_notice("nothing to flush?\n");
278}
279EXPORT_SYMBOL_GPL(amd_flush_garts);
280
281static void __fix_erratum_688(void *info)
282{
283#define MSR_AMD64_IC_CFG 0xC0011021
284
285 msr_set_bit(MSR_AMD64_IC_CFG, bit: 3);
286 msr_set_bit(MSR_AMD64_IC_CFG, bit: 14);
287}
288
289/* Apply erratum 688 fix so machines without a BIOS fix work. */
290static __init void fix_erratum_688(void)
291{
292 struct pci_dev *F4;
293 u32 val;
294
295 if (boot_cpu_data.x86 != 0x14)
296 return;
297
298 if (!amd_northbridges.num)
299 return;
300
301 F4 = node_to_amd_nb(0)->link;
302 if (!F4)
303 return;
304
305 if (pci_read_config_dword(dev: F4, where: 0x164, val: &val))
306 return;
307
308 if (val & BIT(2))
309 return;
310
311 on_each_cpu(func: __fix_erratum_688, NULL, wait: 0);
312
313 pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
314}
315
316static __init int init_amd_nbs(void)
317{
318 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
319 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
320 return 0;
321
322 amd_cache_northbridges();
323 amd_cache_gart();
324
325 fix_erratum_688();
326
327 return 0;
328}
329
330/* This has to go after the PCI subsystem */
331fs_initcall(init_amd_nbs);
332