hc
2024-02-19 1c055e55a242a33e574e48be530e06770a210dcd
kernel/drivers/pci/pcie/dpc.c
....@@ -6,6 +6,8 @@
66 * Copyright (C) 2016 Intel Corp.
77 */
88
9
+#define dev_fmt(fmt) "DPC: " fmt
10
+
911 #include <linux/aer.h>
1012 #include <linux/delay.h>
1113 #include <linux/interrupt.h>
....@@ -14,13 +16,6 @@
1416
1517 #include "portdrv.h"
1618 #include "../pci.h"
17
-
18
-struct dpc_dev {
19
- struct pcie_device *dev;
20
- u16 cap_pos;
21
- bool rp_extensions;
22
- u8 rp_log_size;
23
-};
2419
2520 static const char * const rp_pio_error_string[] = {
2621 "Configuration Request received UR Completion", /* Bit Position 0 */
....@@ -44,12 +39,94 @@
4439 "Memory Request Completion Timeout", /* Bit Position 18 */
4540 };
4641
47
-static int dpc_wait_rp_inactive(struct dpc_dev *dpc)
42
+void pci_save_dpc_state(struct pci_dev *dev)
43
+{
44
+ struct pci_cap_saved_state *save_state;
45
+ u16 *cap;
46
+
47
+ if (!pci_is_pcie(dev))
48
+ return;
49
+
50
+ save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC);
51
+ if (!save_state)
52
+ return;
53
+
54
+ cap = (u16 *)&save_state->cap.data[0];
55
+ pci_read_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, cap);
56
+}
57
+
58
+void pci_restore_dpc_state(struct pci_dev *dev)
59
+{
60
+ struct pci_cap_saved_state *save_state;
61
+ u16 *cap;
62
+
63
+ if (!pci_is_pcie(dev))
64
+ return;
65
+
66
+ save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC);
67
+ if (!save_state)
68
+ return;
69
+
70
+ cap = (u16 *)&save_state->cap.data[0];
71
+ pci_write_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, *cap);
72
+}
73
+
74
+static DECLARE_WAIT_QUEUE_HEAD(dpc_completed_waitqueue);
75
+
76
+#ifdef CONFIG_HOTPLUG_PCI_PCIE
77
+static bool dpc_completed(struct pci_dev *pdev)
78
+{
79
+ u16 status;
80
+
81
+ pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_STATUS, &status);
82
+ if ((status != 0xffff) && (status & PCI_EXP_DPC_STATUS_TRIGGER))
83
+ return false;
84
+
85
+ if (test_bit(PCI_DPC_RECOVERING, &pdev->priv_flags))
86
+ return false;
87
+
88
+ return true;
89
+}
90
+
91
+/**
92
+ * pci_dpc_recovered - whether DPC triggered and has recovered successfully
93
+ * @pdev: PCI device
94
+ *
95
+ * Return true if DPC was triggered for @pdev and has recovered successfully.
96
+ * Wait for recovery if it hasn't completed yet. Called from the PCIe hotplug
97
+ * driver to recognize and ignore Link Down/Up events caused by DPC.
98
+ */
99
+bool pci_dpc_recovered(struct pci_dev *pdev)
100
+{
101
+ struct pci_host_bridge *host;
102
+
103
+ if (!pdev->dpc_cap)
104
+ return false;
105
+
106
+ /*
107
+ * Synchronization between hotplug and DPC is not supported
108
+ * if DPC is owned by firmware and EDR is not enabled.
109
+ */
110
+ host = pci_find_host_bridge(pdev->bus);
111
+ if (!host->native_dpc && !IS_ENABLED(CONFIG_PCIE_EDR))
112
+ return false;
113
+
114
+ /*
115
+ * Need a timeout in case DPC never completes due to failure of
116
+ * dpc_wait_rp_inactive(). The spec doesn't mandate a time limit,
117
+ * but reports indicate that DPC completes within 4 seconds.
118
+ */
119
+ wait_event_timeout(dpc_completed_waitqueue, dpc_completed(pdev),
120
+ msecs_to_jiffies(4000));
121
+
122
+ return test_and_clear_bit(PCI_DPC_RECOVERED, &pdev->priv_flags);
123
+}
124
+#endif /* CONFIG_HOTPLUG_PCI_PCIE */
125
+
126
+static int dpc_wait_rp_inactive(struct pci_dev *pdev)
48127 {
49128 unsigned long timeout = jiffies + HZ;
50
- struct pci_dev *pdev = dpc->dev->port;
51
- struct device *dev = &dpc->dev->device;
52
- u16 cap = dpc->cap_pos, status;
129
+ u16 cap = pdev->dpc_cap, status;
53130
54131 pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
55132 while (status & PCI_EXP_DPC_RP_BUSY &&
....@@ -58,62 +135,70 @@
58135 pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
59136 }
60137 if (status & PCI_EXP_DPC_RP_BUSY) {
61
- dev_warn(dev, "DPC root port still busy\n");
138
+ pci_warn(pdev, "root port still busy\n");
62139 return -EBUSY;
63140 }
64141 return 0;
65142 }
66143
67
-static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
144
+pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
68145 {
69
- struct dpc_dev *dpc;
70
- struct pcie_device *pciedev;
71
- struct device *devdpc;
72
-
146
+ pci_ers_result_t ret;
73147 u16 cap;
148
+
149
+ set_bit(PCI_DPC_RECOVERING, &pdev->priv_flags);
74150
75151 /*
76152 * DPC disables the Link automatically in hardware, so it has
77153 * already been reset by the time we get here.
78154 */
79
- devdpc = pcie_port_find_device(pdev, PCIE_PORT_SERVICE_DPC);
80
- pciedev = to_pcie_device(devdpc);
81
- dpc = get_service_data(pciedev);
82
- cap = dpc->cap_pos;
155
+ cap = pdev->dpc_cap;
83156
84157 /*
85158 * Wait until the Link is inactive, then clear DPC Trigger Status
86159 * to allow the Port to leave DPC.
87160 */
88
- pcie_wait_for_link(pdev, false);
161
+ if (!pcie_wait_for_link(pdev, false))
162
+ pci_info(pdev, "Data Link Layer Link Active not cleared in 1000 msec\n");
89163
90
- if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc))
91
- return PCI_ERS_RESULT_DISCONNECT;
164
+ if (pdev->dpc_rp_extensions && dpc_wait_rp_inactive(pdev)) {
165
+ clear_bit(PCI_DPC_RECOVERED, &pdev->priv_flags);
166
+ ret = PCI_ERS_RESULT_DISCONNECT;
167
+ goto out;
168
+ }
92169
93170 pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
94171 PCI_EXP_DPC_STATUS_TRIGGER);
95172
96
- return PCI_ERS_RESULT_RECOVERED;
173
+ if (pci_bridge_wait_for_secondary_bus(pdev, "DPC",
174
+ PCIE_RESET_READY_POLL_MS)) {
175
+ clear_bit(PCI_DPC_RECOVERED, &pdev->priv_flags);
176
+ ret = PCI_ERS_RESULT_DISCONNECT;
177
+ } else {
178
+ set_bit(PCI_DPC_RECOVERED, &pdev->priv_flags);
179
+ ret = PCI_ERS_RESULT_RECOVERED;
180
+ }
181
+out:
182
+ clear_bit(PCI_DPC_RECOVERING, &pdev->priv_flags);
183
+ wake_up_all(&dpc_completed_waitqueue);
184
+ return ret;
97185 }
98186
99
-
100
-static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
187
+static void dpc_process_rp_pio_error(struct pci_dev *pdev)
101188 {
102
- struct device *dev = &dpc->dev->device;
103
- struct pci_dev *pdev = dpc->dev->port;
104
- u16 cap = dpc->cap_pos, dpc_status, first_error;
189
+ u16 cap = pdev->dpc_cap, dpc_status, first_error;
105190 u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix;
106191 int i;
107192
108193 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, &status);
109194 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_MASK, &mask);
110
- dev_err(dev, "rp_pio_status: %#010x, rp_pio_mask: %#010x\n",
195
+ pci_err(pdev, "rp_pio_status: %#010x, rp_pio_mask: %#010x\n",
111196 status, mask);
112197
113198 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SEVERITY, &sev);
114199 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SYSERROR, &syserr);
115200 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_EXCEPTION, &exc);
116
- dev_err(dev, "RP PIO severity=%#010x, syserror=%#010x, exception=%#010x\n",
201
+ pci_err(pdev, "RP PIO severity=%#010x, syserror=%#010x, exception=%#010x\n",
117202 sev, syserr, exc);
118203
119204 /* Get First Error Pointer */
....@@ -122,11 +207,11 @@
122207
123208 for (i = 0; i < ARRAY_SIZE(rp_pio_error_string); i++) {
124209 if ((status & ~mask) & (1 << i))
125
- dev_err(dev, "[%2d] %s%s\n", i, rp_pio_error_string[i],
210
+ pci_err(pdev, "[%2d] %s%s\n", i, rp_pio_error_string[i],
126211 first_error == i ? " (First)" : "");
127212 }
128213
129
- if (dpc->rp_log_size < 4)
214
+ if (pdev->dpc_rp_log_size < 4)
130215 goto clear_status;
131216 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
132217 &dw0);
....@@ -136,18 +221,18 @@
136221 &dw2);
137222 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 12,
138223 &dw3);
139
- dev_err(dev, "TLP Header: %#010x %#010x %#010x %#010x\n",
224
+ pci_err(pdev, "TLP Header: %#010x %#010x %#010x %#010x\n",
140225 dw0, dw1, dw2, dw3);
141226
142
- if (dpc->rp_log_size < 5)
227
+ if (pdev->dpc_rp_log_size < 5)
143228 goto clear_status;
144229 pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log);
145
- dev_err(dev, "RP PIO ImpSpec Log %#010x\n", log);
230
+ pci_err(pdev, "RP PIO ImpSpec Log %#010x\n", log);
146231
147
- for (i = 0; i < dpc->rp_log_size - 5; i++) {
232
+ for (i = 0; i < pdev->dpc_rp_log_size - 5; i++) {
148233 pci_read_config_dword(pdev,
149234 cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix);
150
- dev_err(dev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
235
+ pci_err(pdev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
151236 }
152237 clear_status:
153238 pci_write_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, status);
....@@ -175,23 +260,20 @@
175260 return 1;
176261 }
177262
178
-static irqreturn_t dpc_handler(int irq, void *context)
263
+void dpc_process_error(struct pci_dev *pdev)
179264 {
265
+ u16 cap = pdev->dpc_cap, status, source, reason, ext_reason;
180266 struct aer_err_info info;
181
- struct dpc_dev *dpc = context;
182
- struct pci_dev *pdev = dpc->dev->port;
183
- struct device *dev = &dpc->dev->device;
184
- u16 cap = dpc->cap_pos, status, source, reason, ext_reason;
185267
186268 pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
187269 pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID, &source);
188270
189
- dev_info(dev, "DPC containment event, status:%#06x source:%#06x\n",
271
+ pci_info(pdev, "containment event, status:%#06x source:%#06x\n",
190272 status, source);
191273
192274 reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN) >> 1;
193275 ext_reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN_EXT) >> 5;
194
- dev_warn(dev, "DPC %s detected, remove downstream devices\n",
276
+ pci_warn(pdev, "%s detected\n",
195277 (reason == 0) ? "unmasked uncorrectable error" :
196278 (reason == 1) ? "ERR_NONFATAL" :
197279 (reason == 2) ? "ERR_FATAL" :
....@@ -200,27 +282,33 @@
200282 "reserved error");
201283
202284 /* show RP PIO error detail information */
203
- if (dpc->rp_extensions && reason == 3 && ext_reason == 0)
204
- dpc_process_rp_pio_error(dpc);
285
+ if (pdev->dpc_rp_extensions && reason == 3 && ext_reason == 0)
286
+ dpc_process_rp_pio_error(pdev);
205287 else if (reason == 0 &&
206288 dpc_get_aer_uncorrect_severity(pdev, &info) &&
207289 aer_get_device_error_info(pdev, &info)) {
208290 aer_print_error(pdev, &info);
209
- pci_cleanup_aer_uncorrect_error_status(pdev);
291
+ pci_aer_clear_nonfatal_status(pdev);
210292 pci_aer_clear_fatal_status(pdev);
211293 }
294
+}
295
+
296
+static irqreturn_t dpc_handler(int irq, void *context)
297
+{
298
+ struct pci_dev *pdev = context;
299
+
300
+ dpc_process_error(pdev);
212301
213302 /* We configure DPC so it only triggers on ERR_FATAL */
214
- pcie_do_fatal_recovery(pdev, PCIE_PORT_SERVICE_DPC);
303
+ pcie_do_recovery(pdev, pci_channel_io_frozen, dpc_reset_link);
215304
216305 return IRQ_HANDLED;
217306 }
218307
219308 static irqreturn_t dpc_irq(int irq, void *context)
220309 {
221
- struct dpc_dev *dpc = (struct dpc_dev *)context;
222
- struct pci_dev *pdev = dpc->dev->port;
223
- u16 cap = dpc->cap_pos, status;
310
+ struct pci_dev *pdev = context;
311
+ u16 cap = pdev->dpc_cap, status;
224312
225313 pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
226314
....@@ -234,68 +322,72 @@
234322 return IRQ_HANDLED;
235323 }
236324
325
+void pci_dpc_init(struct pci_dev *pdev)
326
+{
327
+ u16 cap;
328
+
329
+ pdev->dpc_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
330
+ if (!pdev->dpc_cap)
331
+ return;
332
+
333
+ pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CAP, &cap);
334
+ if (!(cap & PCI_EXP_DPC_CAP_RP_EXT))
335
+ return;
336
+
337
+ pdev->dpc_rp_extensions = true;
338
+ pdev->dpc_rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
339
+ if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) {
340
+ pci_err(pdev, "RP PIO log size %u is invalid\n",
341
+ pdev->dpc_rp_log_size);
342
+ pdev->dpc_rp_log_size = 0;
343
+ }
344
+}
345
+
237346 #define FLAG(x, y) (((x) & (y)) ? '+' : '-')
238347 static int dpc_probe(struct pcie_device *dev)
239348 {
240
- struct dpc_dev *dpc;
241349 struct pci_dev *pdev = dev->port;
242350 struct device *device = &dev->device;
243351 int status;
244352 u16 ctl, cap;
245353
246
- if (pcie_aer_get_firmware_first(pdev))
354
+ if (!pcie_aer_is_native(pdev) && !pcie_ports_dpc_native)
247355 return -ENOTSUPP;
248
-
249
- dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL);
250
- if (!dpc)
251
- return -ENOMEM;
252
-
253
- dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
254
- dpc->dev = dev;
255
- set_service_data(dev, dpc);
256356
257357 status = devm_request_threaded_irq(device, dev->irq, dpc_irq,
258358 dpc_handler, IRQF_SHARED,
259
- "pcie-dpc", dpc);
359
+ "pcie-dpc", pdev);
260360 if (status) {
261
- dev_warn(device, "request IRQ%d failed: %d\n", dev->irq,
361
+ pci_warn(pdev, "request IRQ%d failed: %d\n", dev->irq,
262362 status);
263363 return status;
264364 }
265365
266
- pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap);
267
- pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
268
-
269
- dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT);
270
- if (dpc->rp_extensions) {
271
- dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
272
- if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) {
273
- dev_err(device, "RP PIO log size %u is invalid\n",
274
- dpc->rp_log_size);
275
- dpc->rp_log_size = 0;
276
- }
277
- }
366
+ pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CAP, &cap);
367
+ pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
278368
279369 ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN;
280
- pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
370
+ pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
371
+ pci_info(pdev, "enabled with IRQ %d\n", dev->irq);
281372
282
- dev_info(device, "DPC error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
283
- cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
284
- FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP),
285
- FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size,
286
- FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE));
373
+ pci_info(pdev, "error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
374
+ cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
375
+ FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP),
376
+ FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), pdev->dpc_rp_log_size,
377
+ FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE));
378
+
379
+ pci_add_ext_cap_save_buffer(pdev, PCI_EXT_CAP_ID_DPC, sizeof(u16));
287380 return status;
288381 }
289382
290383 static void dpc_remove(struct pcie_device *dev)
291384 {
292
- struct dpc_dev *dpc = get_service_data(dev);
293385 struct pci_dev *pdev = dev->port;
294386 u16 ctl;
295387
296
- pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
388
+ pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
297389 ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN);
298
- pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
390
+ pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
299391 }
300392
301393 static struct pcie_port_service_driver dpcdriver = {
....@@ -304,7 +396,6 @@
304396 .service = PCIE_PORT_SERVICE_DPC,
305397 .probe = dpc_probe,
306398 .remove = dpc_remove,
307
- .reset_link = dpc_reset_link,
308399 };
309400
310401 int __init pcie_dpc_init(void)