tjh.dev
Linux kernel mirror (for testing)
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linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Intel Platform Monitoring Technology PMT driver
4 *
5 * Copyright (c) 2020, Intel Corporation.
6 * All Rights Reserved.
7 *
8 * Author: David E. Box <david.e.box@linux.intel.com>
9 */
10
11#include <linux/bits.h>
12#include <linux/kernel.h>
13#include <linux/mfd/core.h>
14#include <linux/module.h>
15#include <linux/pci.h>
16#include <linux/platform_device.h>
17#include <linux/pm.h>
18#include <linux/pm_runtime.h>
19#include <linux/types.h>
20
21/* Intel DVSEC capability vendor space offsets */
22#define INTEL_DVSEC_ENTRIES 0xA
23#define INTEL_DVSEC_SIZE 0xB
24#define INTEL_DVSEC_TABLE 0xC
25#define INTEL_DVSEC_TABLE_BAR(x) ((x) & GENMASK(2, 0))
26#define INTEL_DVSEC_TABLE_OFFSET(x) ((x) & GENMASK(31, 3))
27#define INTEL_DVSEC_ENTRY_SIZE 4
28
29/* PMT capabilities */
30#define DVSEC_INTEL_ID_TELEMETRY 2
31#define DVSEC_INTEL_ID_WATCHER 3
32#define DVSEC_INTEL_ID_CRASHLOG 4
33
34struct intel_dvsec_header {
35 u16 length;
36 u16 id;
37 u8 num_entries;
38 u8 entry_size;
39 u8 tbir;
40 u32 offset;
41};
42
43enum pmt_quirks {
44 /* Watcher capability not supported */
45 PMT_QUIRK_NO_WATCHER = BIT(0),
46
47 /* Crashlog capability not supported */
48 PMT_QUIRK_NO_CRASHLOG = BIT(1),
49
50 /* Use shift instead of mask to read discovery table offset */
51 PMT_QUIRK_TABLE_SHIFT = BIT(2),
52
53 /* DVSEC not present (provided in driver data) */
54 PMT_QUIRK_NO_DVSEC = BIT(3),
55};
56
57struct pmt_platform_info {
58 unsigned long quirks;
59 struct intel_dvsec_header **capabilities;
60};
61
62static const struct pmt_platform_info tgl_info = {
63 .quirks = PMT_QUIRK_NO_WATCHER | PMT_QUIRK_NO_CRASHLOG |
64 PMT_QUIRK_TABLE_SHIFT,
65};
66
67/* DG1 Platform with DVSEC quirk*/
68static struct intel_dvsec_header dg1_telemetry = {
69 .length = 0x10,
70 .id = 2,
71 .num_entries = 1,
72 .entry_size = 3,
73 .tbir = 0,
74 .offset = 0x466000,
75};
76
77static struct intel_dvsec_header *dg1_capabilities[] = {
78 &dg1_telemetry,
79 NULL
80};
81
82static const struct pmt_platform_info dg1_info = {
83 .quirks = PMT_QUIRK_NO_DVSEC,
84 .capabilities = dg1_capabilities,
85};
86
87static int pmt_add_dev(struct pci_dev *pdev, struct intel_dvsec_header *header,
88 unsigned long quirks)
89{
90 struct device *dev = &pdev->dev;
91 struct resource *res, *tmp;
92 struct mfd_cell *cell;
93 const char *name;
94 int count = header->num_entries;
95 int size = header->entry_size;
96 int id = header->id;
97 int i;
98
99 switch (id) {
100 case DVSEC_INTEL_ID_TELEMETRY:
101 name = "pmt_telemetry";
102 break;
103 case DVSEC_INTEL_ID_WATCHER:
104 if (quirks & PMT_QUIRK_NO_WATCHER) {
105 dev_info(dev, "Watcher not supported\n");
106 return -EINVAL;
107 }
108 name = "pmt_watcher";
109 break;
110 case DVSEC_INTEL_ID_CRASHLOG:
111 if (quirks & PMT_QUIRK_NO_CRASHLOG) {
112 dev_info(dev, "Crashlog not supported\n");
113 return -EINVAL;
114 }
115 name = "pmt_crashlog";
116 break;
117 default:
118 return -EINVAL;
119 }
120
121 if (!header->num_entries || !header->entry_size) {
122 dev_err(dev, "Invalid count or size for %s header\n", name);
123 return -EINVAL;
124 }
125
126 cell = devm_kzalloc(dev, sizeof(*cell), GFP_KERNEL);
127 if (!cell)
128 return -ENOMEM;
129
130 res = devm_kcalloc(dev, count, sizeof(*res), GFP_KERNEL);
131 if (!res)
132 return -ENOMEM;
133
134 if (quirks & PMT_QUIRK_TABLE_SHIFT)
135 header->offset >>= 3;
136
137 /*
138 * The PMT DVSEC contains the starting offset and count for a block of
139 * discovery tables, each providing access to monitoring facilities for
140 * a section of the device. Create a resource list of these tables to
141 * provide to the driver.
142 */
143 for (i = 0, tmp = res; i < count; i++, tmp++) {
144 tmp->start = pdev->resource[header->tbir].start +
145 header->offset + i * (size << 2);
146 tmp->end = tmp->start + (size << 2) - 1;
147 tmp->flags = IORESOURCE_MEM;
148 }
149
150 cell->resources = res;
151 cell->num_resources = count;
152 cell->name = name;
153
154 return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, cell, 1, NULL, 0,
155 NULL);
156}
157
158static int pmt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
159{
160 struct pmt_platform_info *info;
161 unsigned long quirks = 0;
162 bool found_devices = false;
163 int ret, pos = 0;
164
165 ret = pcim_enable_device(pdev);
166 if (ret)
167 return ret;
168
169 info = (struct pmt_platform_info *)id->driver_data;
170
171 if (info)
172 quirks = info->quirks;
173
174 if (info && (info->quirks & PMT_QUIRK_NO_DVSEC)) {
175 struct intel_dvsec_header **header;
176
177 header = info->capabilities;
178 while (*header) {
179 ret = pmt_add_dev(pdev, *header, quirks);
180 if (ret)
181 dev_warn(&pdev->dev,
182 "Failed to add device for DVSEC id %d\n",
183 (*header)->id);
184 else
185 found_devices = true;
186
187 ++header;
188 }
189 } else {
190 do {
191 struct intel_dvsec_header header;
192 u32 table;
193 u16 vid;
194
195 pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_DVSEC);
196 if (!pos)
197 break;
198
199 pci_read_config_word(pdev, pos + PCI_DVSEC_HEADER1, &vid);
200 if (vid != PCI_VENDOR_ID_INTEL)
201 continue;
202
203 pci_read_config_word(pdev, pos + PCI_DVSEC_HEADER2,
204 &header.id);
205 pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES,
206 &header.num_entries);
207 pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE,
208 &header.entry_size);
209 pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE,
210 &table);
211
212 header.tbir = INTEL_DVSEC_TABLE_BAR(table);
213 header.offset = INTEL_DVSEC_TABLE_OFFSET(table);
214
215 ret = pmt_add_dev(pdev, &header, quirks);
216 if (ret)
217 continue;
218
219 found_devices = true;
220 } while (true);
221 }
222
223 if (!found_devices)
224 return -ENODEV;
225
226 pm_runtime_put(&pdev->dev);
227 pm_runtime_allow(&pdev->dev);
228
229 return 0;
230}
231
232static void pmt_pci_remove(struct pci_dev *pdev)
233{
234 pm_runtime_forbid(&pdev->dev);
235 pm_runtime_get_sync(&pdev->dev);
236}
237
238#define PCI_DEVICE_ID_INTEL_PMT_ADL 0x467d
239#define PCI_DEVICE_ID_INTEL_PMT_DG1 0x490e
240#define PCI_DEVICE_ID_INTEL_PMT_OOBMSM 0x09a7
241#define PCI_DEVICE_ID_INTEL_PMT_TGL 0x9a0d
242static const struct pci_device_id pmt_pci_ids[] = {
243 { PCI_DEVICE_DATA(INTEL, PMT_ADL, &tgl_info) },
244 { PCI_DEVICE_DATA(INTEL, PMT_DG1, &dg1_info) },
245 { PCI_DEVICE_DATA(INTEL, PMT_OOBMSM, NULL) },
246 { PCI_DEVICE_DATA(INTEL, PMT_TGL, &tgl_info) },
247 { }
248};
249MODULE_DEVICE_TABLE(pci, pmt_pci_ids);
250
251static struct pci_driver pmt_pci_driver = {
252 .name = "intel-pmt",
253 .id_table = pmt_pci_ids,
254 .probe = pmt_pci_probe,
255 .remove = pmt_pci_remove,
256};
257module_pci_driver(pmt_pci_driver);
258
259MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
260MODULE_DESCRIPTION("Intel Platform Monitoring Technology PMT driver");
261MODULE_LICENSE("GPL v2");