1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   * The file intends to implement the platform dependent EEH operations on pseries.
4   * Actually, the pseries platform is built based on RTAS heavily. That means the
5   * pseries platform dependent EEH operations will be built on RTAS calls. The functions
6   * are derived from arch/powerpc/platforms/pseries/eeh.c and necessary cleanup has
7   * been done.
8   *
9   * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2011.
10   * Copyright IBM Corporation 2001, 2005, 2006
11   * Copyright Dave Engebretsen & Todd Inglett 2001
12   * Copyright Linas Vepstas 2005, 2006
13   */
14  
15  #include <linux/atomic.h>
16  #include <linux/delay.h>
17  #include <linux/export.h>
18  #include <linux/init.h>
19  #include <linux/list.h>
20  #include <linux/of.h>
21  #include <linux/pci.h>
22  #include <linux/proc_fs.h>
23  #include <linux/rbtree.h>
24  #include <linux/sched.h>
25  #include <linux/seq_file.h>
26  #include <linux/spinlock.h>
27  #include <linux/crash_dump.h>
28  
29  #include <asm/eeh.h>
30  #include <asm/eeh_event.h>
31  #include <asm/io.h>
32  #include <asm/machdep.h>
33  #include <asm/ppc-pci.h>
34  #include <asm/rtas.h>
35  
36  /* RTAS tokens */
37  static int ibm_set_eeh_option;
38  static int ibm_set_slot_reset;
39  static int ibm_read_slot_reset_state;
40  static int ibm_read_slot_reset_state2;
41  static int ibm_slot_error_detail;
42  static int ibm_get_config_addr_info;
43  static int ibm_get_config_addr_info2;
44  static int ibm_configure_pe;
45  
46  static void pseries_eeh_init_edev(struct pci_dn *pdn);
47  
pseries_pcibios_bus_add_device(struct pci_dev * pdev)48  static void pseries_pcibios_bus_add_device(struct pci_dev *pdev)
49  {
50  	struct pci_dn *pdn = pci_get_pdn(pdev);
51  
52  	if (eeh_has_flag(EEH_FORCE_DISABLED))
53  		return;
54  
55  	dev_dbg(&pdev->dev, "EEH: Setting up device\n");
56  #ifdef CONFIG_PCI_IOV
57  	if (pdev->is_virtfn) {
58  		pdn->device_id  =  pdev->device;
59  		pdn->vendor_id  =  pdev->vendor;
60  		pdn->class_code =  pdev->class;
61  		/*
62  		 * Last allow unfreeze return code used for retrieval
63  		 * by user space in eeh-sysfs to show the last command
64  		 * completion from platform.
65  		 */
66  		pdn->last_allow_rc =  0;
67  	}
68  #endif
69  	pseries_eeh_init_edev(pdn);
70  #ifdef CONFIG_PCI_IOV
71  	if (pdev->is_virtfn) {
72  		/*
73  		 * FIXME: This really should be handled by choosing the right
74  		 *        parent PE in pseries_eeh_init_edev().
75  		 */
76  		struct eeh_pe *physfn_pe = pci_dev_to_eeh_dev(pdev->physfn)->pe;
77  		struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
78  
79  		edev->pe_config_addr =  (pdn->busno << 16) | (pdn->devfn << 8);
80  		eeh_pe_tree_remove(edev); /* Remove as it is adding to bus pe */
81  		eeh_pe_tree_insert(edev, physfn_pe);   /* Add as VF PE type */
82  	}
83  #endif
84  	eeh_probe_device(pdev);
85  }
86  
87  
88  /**
89   * pseries_eeh_get_pe_config_addr - Find the pe_config_addr for a device
90   * @pdn: pci_dn of the input device
91   *
92   * The EEH RTAS calls use a tuple consisting of: (buid_hi, buid_lo,
93   * pe_config_addr) as a handle to a given PE. This function finds the
94   * pe_config_addr based on the device's config addr.
95   *
96   * Keep in mind that the pe_config_addr *might* be numerically identical to the
97   * device's config addr, but the two are conceptually distinct.
98   *
99   * Returns the pe_config_addr, or a negative error code.
100   */
pseries_eeh_get_pe_config_addr(struct pci_dn * pdn)101  static int pseries_eeh_get_pe_config_addr(struct pci_dn *pdn)
102  {
103  	int config_addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
104  	struct pci_controller *phb = pdn->phb;
105  	int ret, rets[3];
106  
107  	if (ibm_get_config_addr_info2 != RTAS_UNKNOWN_SERVICE) {
108  		/*
109  		 * First of all, use function 1 to determine if this device is
110  		 * part of a PE or not. ret[0] being zero indicates it's not.
111  		 */
112  		ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
113  				config_addr, BUID_HI(phb->buid),
114  				BUID_LO(phb->buid), 1);
115  		if (ret || (rets[0] == 0))
116  			return -ENOENT;
117  
118  		/* Retrieve the associated PE config address with function 0 */
119  		ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
120  				config_addr, BUID_HI(phb->buid),
121  				BUID_LO(phb->buid), 0);
122  		if (ret) {
123  			pr_warn("%s: Failed to get address for PHB#%x-PE#%x\n",
124  				__func__, phb->global_number, config_addr);
125  			return -ENXIO;
126  		}
127  
128  		return rets[0];
129  	}
130  
131  	if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) {
132  		ret = rtas_call(ibm_get_config_addr_info, 4, 2, rets,
133  				config_addr, BUID_HI(phb->buid),
134  				BUID_LO(phb->buid), 0);
135  		if (ret) {
136  			pr_warn("%s: Failed to get address for PHB#%x-PE#%x\n",
137  				__func__, phb->global_number, config_addr);
138  			return -ENXIO;
139  		}
140  
141  		return rets[0];
142  	}
143  
144  	/*
145  	 * PAPR does describe a process for finding the pe_config_addr that was
146  	 * used before the ibm,get-config-addr-info calls were added. However,
147  	 * I haven't found *any* systems that don't have that RTAS call
148  	 * implemented. If you happen to find one that needs the old DT based
149  	 * process, patches are welcome!
150  	 */
151  	return -ENOENT;
152  }
153  
154  /**
155   * pseries_eeh_phb_reset - Reset the specified PHB
156   * @phb: PCI controller
157   * @config_addr: the associated config address
158   * @option: reset option
159   *
160   * Reset the specified PHB/PE
161   */
pseries_eeh_phb_reset(struct pci_controller * phb,int config_addr,int option)162  static int pseries_eeh_phb_reset(struct pci_controller *phb, int config_addr, int option)
163  {
164  	int ret;
165  
166  	/* Reset PE through RTAS call */
167  	ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
168  			config_addr, BUID_HI(phb->buid),
169  			BUID_LO(phb->buid), option);
170  
171  	/* If fundamental-reset not supported, try hot-reset */
172  	if (option == EEH_RESET_FUNDAMENTAL && ret == -8) {
173  		option = EEH_RESET_HOT;
174  		ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
175  				config_addr, BUID_HI(phb->buid),
176  				BUID_LO(phb->buid), option);
177  	}
178  
179  	/* We need reset hold or settlement delay */
180  	if (option == EEH_RESET_FUNDAMENTAL || option == EEH_RESET_HOT)
181  		msleep(EEH_PE_RST_HOLD_TIME);
182  	else
183  		msleep(EEH_PE_RST_SETTLE_TIME);
184  
185  	return ret;
186  }
187  
188  /**
189   * pseries_eeh_phb_configure_bridge - Configure PCI bridges in the indicated PE
190   * @phb: PCI controller
191   * @config_addr: the associated config address
192   *
193   * The function will be called to reconfigure the bridges included
194   * in the specified PE so that the mulfunctional PE would be recovered
195   * again.
196   */
pseries_eeh_phb_configure_bridge(struct pci_controller * phb,int config_addr)197  static int pseries_eeh_phb_configure_bridge(struct pci_controller *phb, int config_addr)
198  {
199  	int ret;
200  	/* Waiting 0.2s maximum before skipping configuration */
201  	int max_wait = 200;
202  
203  	while (max_wait > 0) {
204  		ret = rtas_call(ibm_configure_pe, 3, 1, NULL,
205  				config_addr, BUID_HI(phb->buid),
206  				BUID_LO(phb->buid));
207  
208  		if (!ret)
209  			return ret;
210  		if (ret < 0)
211  			break;
212  
213  		/*
214  		 * If RTAS returns a delay value that's above 100ms, cut it
215  		 * down to 100ms in case firmware made a mistake.  For more
216  		 * on how these delay values work see rtas_busy_delay_time
217  		 */
218  		if (ret > RTAS_EXTENDED_DELAY_MIN+2 &&
219  		    ret <= RTAS_EXTENDED_DELAY_MAX)
220  			ret = RTAS_EXTENDED_DELAY_MIN+2;
221  
222  		max_wait -= rtas_busy_delay_time(ret);
223  
224  		if (max_wait < 0)
225  			break;
226  
227  		rtas_busy_delay(ret);
228  	}
229  
230  	pr_warn("%s: Unable to configure bridge PHB#%x-PE#%x (%d)\n",
231  		__func__, phb->global_number, config_addr, ret);
232  	/* PAPR defines -3 as "Parameter Error" for this function: */
233  	if (ret == -3)
234  		return -EINVAL;
235  	else
236  		return -EIO;
237  }
238  
239  /*
240   * Buffer for reporting slot-error-detail rtas calls. Its here
241   * in BSS, and not dynamically alloced, so that it ends up in
242   * RMO where RTAS can access it.
243   */
244  static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX];
245  static DEFINE_SPINLOCK(slot_errbuf_lock);
246  static int eeh_error_buf_size;
247  
pseries_eeh_cap_start(struct pci_dn * pdn)248  static int pseries_eeh_cap_start(struct pci_dn *pdn)
249  {
250  	u32 status;
251  
252  	if (!pdn)
253  		return 0;
254  
255  	rtas_pci_dn_read_config(pdn, PCI_STATUS, 2, &status);
256  	if (!(status & PCI_STATUS_CAP_LIST))
257  		return 0;
258  
259  	return PCI_CAPABILITY_LIST;
260  }
261  
262  
pseries_eeh_find_cap(struct pci_dn * pdn,int cap)263  static int pseries_eeh_find_cap(struct pci_dn *pdn, int cap)
264  {
265  	int pos = pseries_eeh_cap_start(pdn);
266  	int cnt = 48;	/* Maximal number of capabilities */
267  	u32 id;
268  
269  	if (!pos)
270  		return 0;
271  
272          while (cnt--) {
273  		rtas_pci_dn_read_config(pdn, pos, 1, &pos);
274  		if (pos < 0x40)
275  			break;
276  		pos &= ~3;
277  		rtas_pci_dn_read_config(pdn, pos + PCI_CAP_LIST_ID, 1, &id);
278  		if (id == 0xff)
279  			break;
280  		if (id == cap)
281  			return pos;
282  		pos += PCI_CAP_LIST_NEXT;
283  	}
284  
285  	return 0;
286  }
287  
pseries_eeh_find_ecap(struct pci_dn * pdn,int cap)288  static int pseries_eeh_find_ecap(struct pci_dn *pdn, int cap)
289  {
290  	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
291  	u32 header;
292  	int pos = 256;
293  	int ttl = (4096 - 256) / 8;
294  
295  	if (!edev || !edev->pcie_cap)
296  		return 0;
297  	if (rtas_pci_dn_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
298  		return 0;
299  	else if (!header)
300  		return 0;
301  
302  	while (ttl-- > 0) {
303  		if (PCI_EXT_CAP_ID(header) == cap && pos)
304  			return pos;
305  
306  		pos = PCI_EXT_CAP_NEXT(header);
307  		if (pos < 256)
308  			break;
309  
310  		if (rtas_pci_dn_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
311  			break;
312  	}
313  
314  	return 0;
315  }
316  
317  /**
318   * pseries_eeh_pe_get_parent - Retrieve the parent PE
319   * @edev: EEH device
320   *
321   * The whole PEs existing in the system are organized as hierarchy
322   * tree. The function is used to retrieve the parent PE according
323   * to the parent EEH device.
324   */
pseries_eeh_pe_get_parent(struct eeh_dev * edev)325  static struct eeh_pe *pseries_eeh_pe_get_parent(struct eeh_dev *edev)
326  {
327  	struct eeh_dev *parent;
328  	struct pci_dn *pdn = eeh_dev_to_pdn(edev);
329  
330  	/*
331  	 * It might have the case for the indirect parent
332  	 * EEH device already having associated PE, but
333  	 * the direct parent EEH device doesn't have yet.
334  	 */
335  	if (edev->physfn)
336  		pdn = pci_get_pdn(edev->physfn);
337  	else
338  		pdn = pdn ? pdn->parent : NULL;
339  	while (pdn) {
340  		/* We're poking out of PCI territory */
341  		parent = pdn_to_eeh_dev(pdn);
342  		if (!parent)
343  			return NULL;
344  
345  		if (parent->pe)
346  			return parent->pe;
347  
348  		pdn = pdn->parent;
349  	}
350  
351  	return NULL;
352  }
353  
354  /**
355   * pseries_eeh_init_edev - initialise the eeh_dev and eeh_pe for a pci_dn
356   *
357   * @pdn: PCI device node
358   *
359   * When we discover a new PCI device via the device-tree we create a
360   * corresponding pci_dn and we allocate, but don't initialise, an eeh_dev.
361   * This function takes care of the initialisation and inserts the eeh_dev
362   * into the correct eeh_pe. If no eeh_pe exists we'll allocate one.
363   */
pseries_eeh_init_edev(struct pci_dn * pdn)364  static void pseries_eeh_init_edev(struct pci_dn *pdn)
365  {
366  	struct eeh_pe pe, *parent;
367  	struct eeh_dev *edev;
368  	u32 pcie_flags;
369  	int ret;
370  
371  	if (WARN_ON_ONCE(!eeh_has_flag(EEH_PROBE_MODE_DEVTREE)))
372  		return;
373  
374  	/*
375  	 * Find the eeh_dev for this pdn. The storage for the eeh_dev was
376  	 * allocated at the same time as the pci_dn.
377  	 *
378  	 * XXX: We should probably re-visit that.
379  	 */
380  	edev = pdn_to_eeh_dev(pdn);
381  	if (!edev)
382  		return;
383  
384  	/*
385  	 * If ->pe is set then we've already probed this device. We hit
386  	 * this path when a pci_dev is removed and rescanned while recovering
387  	 * a PE (i.e. for devices where the driver doesn't support error
388  	 * recovery).
389  	 */
390  	if (edev->pe)
391  		return;
392  
393  	/* Check class/vendor/device IDs */
394  	if (!pdn->vendor_id || !pdn->device_id || !pdn->class_code)
395  		return;
396  
397  	/* Skip for PCI-ISA bridge */
398          if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_ISA)
399  		return;
400  
401  	eeh_edev_dbg(edev, "Probing device\n");
402  
403  	/*
404  	 * Update class code and mode of eeh device. We need
405  	 * correctly reflects that current device is root port
406  	 * or PCIe switch downstream port.
407  	 */
408  	edev->pcix_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
409  	edev->pcie_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
410  	edev->aer_cap = pseries_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
411  	edev->mode &= 0xFFFFFF00;
412  	if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
413  		edev->mode |= EEH_DEV_BRIDGE;
414  		if (edev->pcie_cap) {
415  			rtas_pci_dn_read_config(pdn, edev->pcie_cap + PCI_EXP_FLAGS,
416  						2, &pcie_flags);
417  			pcie_flags = (pcie_flags & PCI_EXP_FLAGS_TYPE) >> 4;
418  			if (pcie_flags == PCI_EXP_TYPE_ROOT_PORT)
419  				edev->mode |= EEH_DEV_ROOT_PORT;
420  			else if (pcie_flags == PCI_EXP_TYPE_DOWNSTREAM)
421  				edev->mode |= EEH_DEV_DS_PORT;
422  		}
423  	}
424  
425  	/* first up, find the pe_config_addr for the PE containing the device */
426  	ret = pseries_eeh_get_pe_config_addr(pdn);
427  	if (ret < 0) {
428  		eeh_edev_dbg(edev, "Unable to find pe_config_addr\n");
429  		goto err;
430  	}
431  
432  	/* Try enable EEH on the fake PE */
433  	memset(&pe, 0, sizeof(struct eeh_pe));
434  	pe.phb = pdn->phb;
435  	pe.addr = ret;
436  
437  	eeh_edev_dbg(edev, "Enabling EEH on device\n");
438  	ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
439  	if (ret) {
440  		eeh_edev_dbg(edev, "EEH failed to enable on device (code %d)\n", ret);
441  		goto err;
442  	}
443  
444  	edev->pe_config_addr = pe.addr;
445  
446  	eeh_add_flag(EEH_ENABLED);
447  
448  	parent = pseries_eeh_pe_get_parent(edev);
449  	eeh_pe_tree_insert(edev, parent);
450  	eeh_save_bars(edev);
451  	eeh_edev_dbg(edev, "EEH enabled for device");
452  
453  	return;
454  
455  err:
456  	eeh_edev_dbg(edev, "EEH is unsupported on device (code = %d)\n", ret);
457  }
458  
pseries_eeh_probe(struct pci_dev * pdev)459  static struct eeh_dev *pseries_eeh_probe(struct pci_dev *pdev)
460  {
461  	struct eeh_dev *edev;
462  	struct pci_dn *pdn;
463  
464  	pdn = pci_get_pdn_by_devfn(pdev->bus, pdev->devfn);
465  	if (!pdn)
466  		return NULL;
467  
468  	/*
469  	 * If the system supports EEH on this device then the eeh_dev was
470  	 * configured and inserted into a PE in pseries_eeh_init_edev()
471  	 */
472  	edev = pdn_to_eeh_dev(pdn);
473  	if (!edev || !edev->pe)
474  		return NULL;
475  
476  	return edev;
477  }
478  
479  /**
480   * pseries_eeh_init_edev_recursive - Enable EEH for the indicated device
481   * @pdn: PCI device node
482   *
483   * This routine must be used to perform EEH initialization for the
484   * indicated PCI device that was added after system boot (e.g.
485   * hotplug, dlpar).
486   */
pseries_eeh_init_edev_recursive(struct pci_dn * pdn)487  void pseries_eeh_init_edev_recursive(struct pci_dn *pdn)
488  {
489  	struct pci_dn *n;
490  
491  	if (!pdn)
492  		return;
493  
494  	list_for_each_entry(n, &pdn->child_list, list)
495  		pseries_eeh_init_edev_recursive(n);
496  
497  	pseries_eeh_init_edev(pdn);
498  }
499  EXPORT_SYMBOL_GPL(pseries_eeh_init_edev_recursive);
500  
501  /**
502   * pseries_eeh_set_option - Initialize EEH or MMIO/DMA reenable
503   * @pe: EEH PE
504   * @option: operation to be issued
505   *
506   * The function is used to control the EEH functionality globally.
507   * Currently, following options are support according to PAPR:
508   * Enable EEH, Disable EEH, Enable MMIO and Enable DMA
509   */
pseries_eeh_set_option(struct eeh_pe * pe,int option)510  static int pseries_eeh_set_option(struct eeh_pe *pe, int option)
511  {
512  	int ret = 0;
513  
514  	/*
515  	 * When we're enabling or disabling EEH functionality on
516  	 * the particular PE, the PE config address is possibly
517  	 * unavailable. Therefore, we have to figure it out from
518  	 * the FDT node.
519  	 */
520  	switch (option) {
521  	case EEH_OPT_DISABLE:
522  	case EEH_OPT_ENABLE:
523  	case EEH_OPT_THAW_MMIO:
524  	case EEH_OPT_THAW_DMA:
525  		break;
526  	case EEH_OPT_FREEZE_PE:
527  		/* Not support */
528  		return 0;
529  	default:
530  		pr_err("%s: Invalid option %d\n", __func__, option);
531  		return -EINVAL;
532  	}
533  
534  	ret = rtas_call(ibm_set_eeh_option, 4, 1, NULL,
535  			pe->addr, BUID_HI(pe->phb->buid),
536  			BUID_LO(pe->phb->buid), option);
537  
538  	return ret;
539  }
540  
541  /**
542   * pseries_eeh_get_state - Retrieve PE state
543   * @pe: EEH PE
544   * @delay: suggested time to wait if state is unavailable
545   *
546   * Retrieve the state of the specified PE. On RTAS compliant
547   * pseries platform, there already has one dedicated RTAS function
548   * for the purpose. It's notable that the associated PE config address
549   * might be ready when calling the function. Therefore, endeavour to
550   * use the PE config address if possible. Further more, there're 2
551   * RTAS calls for the purpose, we need to try the new one and back
552   * to the old one if the new one couldn't work properly.
553   */
pseries_eeh_get_state(struct eeh_pe * pe,int * delay)554  static int pseries_eeh_get_state(struct eeh_pe *pe, int *delay)
555  {
556  	int ret;
557  	int rets[4];
558  	int result;
559  
560  	if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) {
561  		ret = rtas_call(ibm_read_slot_reset_state2, 3, 4, rets,
562  				pe->addr, BUID_HI(pe->phb->buid),
563  				BUID_LO(pe->phb->buid));
564  	} else if (ibm_read_slot_reset_state != RTAS_UNKNOWN_SERVICE) {
565  		/* Fake PE unavailable info */
566  		rets[2] = 0;
567  		ret = rtas_call(ibm_read_slot_reset_state, 3, 3, rets,
568  				pe->addr, BUID_HI(pe->phb->buid),
569  				BUID_LO(pe->phb->buid));
570  	} else {
571  		return EEH_STATE_NOT_SUPPORT;
572  	}
573  
574  	if (ret)
575  		return ret;
576  
577  	/* Parse the result out */
578  	if (!rets[1])
579  		return EEH_STATE_NOT_SUPPORT;
580  
581  	switch(rets[0]) {
582  	case 0:
583  		result = EEH_STATE_MMIO_ACTIVE |
584  			 EEH_STATE_DMA_ACTIVE;
585  		break;
586  	case 1:
587  		result = EEH_STATE_RESET_ACTIVE |
588  			 EEH_STATE_MMIO_ACTIVE  |
589  			 EEH_STATE_DMA_ACTIVE;
590  		break;
591  	case 2:
592  		result = 0;
593  		break;
594  	case 4:
595  		result = EEH_STATE_MMIO_ENABLED;
596  		break;
597  	case 5:
598  		if (rets[2]) {
599  			if (delay)
600  				*delay = rets[2];
601  			result = EEH_STATE_UNAVAILABLE;
602  		} else {
603  			result = EEH_STATE_NOT_SUPPORT;
604  		}
605  		break;
606  	default:
607  		result = EEH_STATE_NOT_SUPPORT;
608  	}
609  
610  	return result;
611  }
612  
613  /**
614   * pseries_eeh_reset - Reset the specified PE
615   * @pe: EEH PE
616   * @option: reset option
617   *
618   * Reset the specified PE
619   */
pseries_eeh_reset(struct eeh_pe * pe,int option)620  static int pseries_eeh_reset(struct eeh_pe *pe, int option)
621  {
622  	return pseries_eeh_phb_reset(pe->phb, pe->addr, option);
623  }
624  
625  /**
626   * pseries_eeh_get_log - Retrieve error log
627   * @pe: EEH PE
628   * @severity: temporary or permanent error log
629   * @drv_log: driver log to be combined with retrieved error log
630   * @len: length of driver log
631   *
632   * Retrieve the temporary or permanent error from the PE.
633   * Actually, the error will be retrieved through the dedicated
634   * RTAS call.
635   */
pseries_eeh_get_log(struct eeh_pe * pe,int severity,char * drv_log,unsigned long len)636  static int pseries_eeh_get_log(struct eeh_pe *pe, int severity, char *drv_log, unsigned long len)
637  {
638  	unsigned long flags;
639  	int ret;
640  
641  	spin_lock_irqsave(&slot_errbuf_lock, flags);
642  	memset(slot_errbuf, 0, eeh_error_buf_size);
643  
644  	ret = rtas_call(ibm_slot_error_detail, 8, 1, NULL, pe->addr,
645  			BUID_HI(pe->phb->buid), BUID_LO(pe->phb->buid),
646  			virt_to_phys(drv_log), len,
647  			virt_to_phys(slot_errbuf), eeh_error_buf_size,
648  			severity);
649  	if (!ret)
650  		log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
651  	spin_unlock_irqrestore(&slot_errbuf_lock, flags);
652  
653  	return ret;
654  }
655  
656  /**
657   * pseries_eeh_configure_bridge - Configure PCI bridges in the indicated PE
658   * @pe: EEH PE
659   *
660   */
pseries_eeh_configure_bridge(struct eeh_pe * pe)661  static int pseries_eeh_configure_bridge(struct eeh_pe *pe)
662  {
663  	return pseries_eeh_phb_configure_bridge(pe->phb, pe->addr);
664  }
665  
666  /**
667   * pseries_eeh_read_config - Read PCI config space
668   * @edev: EEH device handle
669   * @where: PCI config space offset
670   * @size: size to read
671   * @val: return value
672   *
673   * Read config space from the speicifed device
674   */
pseries_eeh_read_config(struct eeh_dev * edev,int where,int size,u32 * val)675  static int pseries_eeh_read_config(struct eeh_dev *edev, int where, int size, u32 *val)
676  {
677  	struct pci_dn *pdn = eeh_dev_to_pdn(edev);
678  
679  	return rtas_pci_dn_read_config(pdn, where, size, val);
680  }
681  
682  /**
683   * pseries_eeh_write_config - Write PCI config space
684   * @edev: EEH device handle
685   * @where: PCI config space offset
686   * @size: size to write
687   * @val: value to be written
688   *
689   * Write config space to the specified device
690   */
pseries_eeh_write_config(struct eeh_dev * edev,int where,int size,u32 val)691  static int pseries_eeh_write_config(struct eeh_dev *edev, int where, int size, u32 val)
692  {
693  	struct pci_dn *pdn = eeh_dev_to_pdn(edev);
694  
695  	return rtas_pci_dn_write_config(pdn, where, size, val);
696  }
697  
698  #ifdef CONFIG_PCI_IOV
pseries_send_allow_unfreeze(struct pci_dn * pdn,u16 * vf_pe_array,int cur_vfs)699  static int pseries_send_allow_unfreeze(struct pci_dn *pdn, u16 *vf_pe_array, int cur_vfs)
700  {
701  	int rc;
702  	int ibm_allow_unfreeze = rtas_function_token(RTAS_FN_IBM_OPEN_SRIOV_ALLOW_UNFREEZE);
703  	unsigned long buid, addr;
704  
705  	addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
706  	buid = pdn->phb->buid;
707  	spin_lock(&rtas_data_buf_lock);
708  	memcpy(rtas_data_buf, vf_pe_array, RTAS_DATA_BUF_SIZE);
709  	rc = rtas_call(ibm_allow_unfreeze, 5, 1, NULL,
710  		       addr,
711  		       BUID_HI(buid),
712  		       BUID_LO(buid),
713  		       rtas_data_buf, cur_vfs * sizeof(u16));
714  	spin_unlock(&rtas_data_buf_lock);
715  	if (rc)
716  		pr_warn("%s: Failed to allow unfreeze for PHB#%x-PE#%lx, rc=%x\n",
717  			__func__,
718  			pdn->phb->global_number, addr, rc);
719  	return rc;
720  }
721  
pseries_call_allow_unfreeze(struct eeh_dev * edev)722  static int pseries_call_allow_unfreeze(struct eeh_dev *edev)
723  {
724  	int cur_vfs = 0, rc = 0, vf_index, bus, devfn, vf_pe_num;
725  	struct pci_dn *pdn, *tmp, *parent, *physfn_pdn;
726  	u16 *vf_pe_array;
727  
728  	vf_pe_array = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
729  	if (!vf_pe_array)
730  		return -ENOMEM;
731  	if (pci_num_vf(edev->physfn ? edev->physfn : edev->pdev)) {
732  		if (edev->pdev->is_physfn) {
733  			cur_vfs = pci_num_vf(edev->pdev);
734  			pdn = eeh_dev_to_pdn(edev);
735  			parent = pdn->parent;
736  			for (vf_index = 0; vf_index < cur_vfs; vf_index++)
737  				vf_pe_array[vf_index] =
738  					cpu_to_be16(pdn->pe_num_map[vf_index]);
739  			rc = pseries_send_allow_unfreeze(pdn, vf_pe_array,
740  							 cur_vfs);
741  			pdn->last_allow_rc = rc;
742  			for (vf_index = 0; vf_index < cur_vfs; vf_index++) {
743  				list_for_each_entry_safe(pdn, tmp,
744  							 &parent->child_list,
745  							 list) {
746  					bus = pci_iov_virtfn_bus(edev->pdev,
747  								 vf_index);
748  					devfn = pci_iov_virtfn_devfn(edev->pdev,
749  								     vf_index);
750  					if (pdn->busno != bus ||
751  					    pdn->devfn != devfn)
752  						continue;
753  					pdn->last_allow_rc = rc;
754  				}
755  			}
756  		} else {
757  			pdn = pci_get_pdn(edev->pdev);
758  			physfn_pdn = pci_get_pdn(edev->physfn);
759  
760  			vf_pe_num = physfn_pdn->pe_num_map[edev->vf_index];
761  			vf_pe_array[0] = cpu_to_be16(vf_pe_num);
762  			rc = pseries_send_allow_unfreeze(physfn_pdn,
763  							 vf_pe_array, 1);
764  			pdn->last_allow_rc = rc;
765  		}
766  	}
767  
768  	kfree(vf_pe_array);
769  	return rc;
770  }
771  
pseries_notify_resume(struct eeh_dev * edev)772  static int pseries_notify_resume(struct eeh_dev *edev)
773  {
774  	if (!edev)
775  		return -EEXIST;
776  
777  	if (rtas_function_token(RTAS_FN_IBM_OPEN_SRIOV_ALLOW_UNFREEZE) == RTAS_UNKNOWN_SERVICE)
778  		return -EINVAL;
779  
780  	if (edev->pdev->is_physfn || edev->pdev->is_virtfn)
781  		return pseries_call_allow_unfreeze(edev);
782  
783  	return 0;
784  }
785  #endif
786  
787  /**
788   * pseries_eeh_err_inject - Inject specified error to the indicated PE
789   * @pe: the indicated PE
790   * @type: error type
791   * @func: specific error type
792   * @addr: address
793   * @mask: address mask
794   * The routine is called to inject specified error, which is
795   * determined by @type and @func, to the indicated PE
796   */
pseries_eeh_err_inject(struct eeh_pe * pe,int type,int func,unsigned long addr,unsigned long mask)797  static int pseries_eeh_err_inject(struct eeh_pe *pe, int type, int func,
798  				  unsigned long addr, unsigned long mask)
799  {
800  	struct	eeh_dev	*pdev;
801  
802  	/* Check on PCI error type */
803  	if (type != EEH_ERR_TYPE_32 && type != EEH_ERR_TYPE_64)
804  		return -EINVAL;
805  
806  	switch (func) {
807  	case EEH_ERR_FUNC_LD_MEM_ADDR:
808  	case EEH_ERR_FUNC_LD_MEM_DATA:
809  	case EEH_ERR_FUNC_ST_MEM_ADDR:
810  	case EEH_ERR_FUNC_ST_MEM_DATA:
811  		/* injects a MMIO error for all pdev's belonging to PE */
812  		pci_lock_rescan_remove();
813  		list_for_each_entry(pdev, &pe->edevs, entry)
814  			eeh_pe_inject_mmio_error(pdev->pdev);
815  		pci_unlock_rescan_remove();
816  		break;
817  	default:
818  		return -ERANGE;
819  	}
820  
821  	return 0;
822  }
823  
824  static struct eeh_ops pseries_eeh_ops = {
825  	.name			= "pseries",
826  	.probe			= pseries_eeh_probe,
827  	.set_option		= pseries_eeh_set_option,
828  	.get_state		= pseries_eeh_get_state,
829  	.reset			= pseries_eeh_reset,
830  	.get_log		= pseries_eeh_get_log,
831  	.configure_bridge       = pseries_eeh_configure_bridge,
832  	.err_inject		= pseries_eeh_err_inject,
833  	.read_config		= pseries_eeh_read_config,
834  	.write_config		= pseries_eeh_write_config,
835  	.next_error		= NULL,
836  	.restore_config		= NULL, /* NB: configure_bridge() does this */
837  #ifdef CONFIG_PCI_IOV
838  	.notify_resume		= pseries_notify_resume
839  #endif
840  };
841  
842  /**
843   * eeh_pseries_init - Register platform dependent EEH operations
844   *
845   * EEH initialization on pseries platform. This function should be
846   * called before any EEH related functions.
847   */
eeh_pseries_init(void)848  static int __init eeh_pseries_init(void)
849  {
850  	struct pci_controller *phb;
851  	struct pci_dn *pdn;
852  	int ret, config_addr;
853  
854  	/* figure out EEH RTAS function call tokens */
855  	ibm_set_eeh_option		= rtas_function_token(RTAS_FN_IBM_SET_EEH_OPTION);
856  	ibm_set_slot_reset		= rtas_function_token(RTAS_FN_IBM_SET_SLOT_RESET);
857  	ibm_read_slot_reset_state2	= rtas_function_token(RTAS_FN_IBM_READ_SLOT_RESET_STATE2);
858  	ibm_read_slot_reset_state	= rtas_function_token(RTAS_FN_IBM_READ_SLOT_RESET_STATE);
859  	ibm_slot_error_detail		= rtas_function_token(RTAS_FN_IBM_SLOT_ERROR_DETAIL);
860  	ibm_get_config_addr_info2	= rtas_function_token(RTAS_FN_IBM_GET_CONFIG_ADDR_INFO2);
861  	ibm_get_config_addr_info	= rtas_function_token(RTAS_FN_IBM_GET_CONFIG_ADDR_INFO);
862  	ibm_configure_pe		= rtas_function_token(RTAS_FN_IBM_CONFIGURE_PE);
863  
864  	/*
865  	 * ibm,configure-pe and ibm,configure-bridge have the same semantics,
866  	 * however ibm,configure-pe can be faster.  If we can't find
867  	 * ibm,configure-pe then fall back to using ibm,configure-bridge.
868  	 */
869  	if (ibm_configure_pe == RTAS_UNKNOWN_SERVICE)
870  		ibm_configure_pe	= rtas_function_token(RTAS_FN_IBM_CONFIGURE_BRIDGE);
871  
872  	/*
873  	 * Necessary sanity check. We needn't check "get-config-addr-info"
874  	 * and its variant since the old firmware probably support address
875  	 * of domain/bus/slot/function for EEH RTAS operations.
876  	 */
877  	if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE		||
878  	    ibm_set_slot_reset == RTAS_UNKNOWN_SERVICE		||
879  	    (ibm_read_slot_reset_state2 == RTAS_UNKNOWN_SERVICE &&
880  	     ibm_read_slot_reset_state == RTAS_UNKNOWN_SERVICE)	||
881  	    ibm_slot_error_detail == RTAS_UNKNOWN_SERVICE	||
882  	    ibm_configure_pe == RTAS_UNKNOWN_SERVICE) {
883  		pr_info("EEH functionality not supported\n");
884  		return -EINVAL;
885  	}
886  
887  	/* Initialize error log size */
888  	eeh_error_buf_size = rtas_get_error_log_max();
889  
890  	/* Set EEH probe mode */
891  	eeh_add_flag(EEH_PROBE_MODE_DEVTREE | EEH_ENABLE_IO_FOR_LOG);
892  
893  	/* Set EEH machine dependent code */
894  	ppc_md.pcibios_bus_add_device = pseries_pcibios_bus_add_device;
895  
896  	if (is_kdump_kernel() || reset_devices) {
897  		pr_info("Issue PHB reset ...\n");
898  		list_for_each_entry(phb, &hose_list, list_node) {
899  			// Skip if the slot is empty
900  			if (list_empty(&PCI_DN(phb->dn)->child_list))
901  				continue;
902  
903  			pdn = list_first_entry(&PCI_DN(phb->dn)->child_list, struct pci_dn, list);
904  			config_addr = pseries_eeh_get_pe_config_addr(pdn);
905  
906  			/* invalid PE config addr */
907  			if (config_addr < 0)
908  				continue;
909  
910  			pseries_eeh_phb_reset(phb, config_addr, EEH_RESET_FUNDAMENTAL);
911  			pseries_eeh_phb_reset(phb, config_addr, EEH_RESET_DEACTIVATE);
912  			pseries_eeh_phb_configure_bridge(phb, config_addr);
913  		}
914  	}
915  
916  	ret = eeh_init(&pseries_eeh_ops);
917  	if (!ret)
918  		pr_info("EEH: pSeries platform initialized\n");
919  	else
920  		pr_info("EEH: pSeries platform initialization failure (%d)\n",
921  			ret);
922  	return ret;
923  }
924  machine_arch_initcall(pseries, eeh_pseries_init);
925