1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2001  Dave Engebretsen & Todd Inglett IBM Corporation.
4  * Copyright 2001-2012 IBM Corporation.
5  */
6 
7 #ifndef _POWERPC_EEH_H
8 #define _POWERPC_EEH_H
9 #ifdef __KERNEL__
10 
11 #include <linux/init.h>
12 #include <linux/list.h>
13 #include <linux/string.h>
14 #include <linux/time.h>
15 #include <linux/atomic.h>
16 
17 #include <uapi/asm/eeh.h>
18 
19 struct pci_dev;
20 struct pci_bus;
21 struct pci_dn;
22 
23 #ifdef CONFIG_EEH
24 
25 /* EEH subsystem flags */
26 #define EEH_ENABLED		0x01	/* EEH enabled			     */
27 #define EEH_FORCE_DISABLED	0x02	/* EEH disabled			     */
28 #define EEH_PROBE_MODE_DEV	0x04	/* From PCI device		     */
29 #define EEH_PROBE_MODE_DEVTREE	0x08	/* From device tree		     */
30 #define EEH_ENABLE_IO_FOR_LOG	0x20	/* Enable IO for log		     */
31 #define EEH_EARLY_DUMP_LOG	0x40	/* Dump log immediately		     */
32 
33 /*
34  * Delay for PE reset, all in ms
35  *
36  * PCI specification has reset hold time of 100 milliseconds.
37  * We have 250 milliseconds here. The PCI bus settlement time
38  * is specified as 1.5 seconds and we have 1.8 seconds.
39  */
40 #define EEH_PE_RST_HOLD_TIME		250
41 #define EEH_PE_RST_SETTLE_TIME		1800
42 
43 /*
44  * The struct is used to trace PE related EEH functionality.
45  * In theory, there will have one instance of the struct to
46  * be created against particular PE. In nature, PEs correlate
47  * to each other. the struct has to reflect that hierarchy in
48  * order to easily pick up those affected PEs when one particular
49  * PE has EEH errors.
50  *
51  * Also, one particular PE might be composed of PCI device, PCI
52  * bus and its subordinate components. The struct also need ship
53  * the information. Further more, one particular PE is only meaingful
54  * in the corresponding PHB. Therefore, the root PEs should be created
55  * against existing PHBs in on-to-one fashion.
56  */
57 #define EEH_PE_INVALID	(1 << 0)	/* Invalid   */
58 #define EEH_PE_PHB	(1 << 1)	/* PHB PE    */
59 #define EEH_PE_DEVICE 	(1 << 2)	/* Device PE */
60 #define EEH_PE_BUS	(1 << 3)	/* Bus PE    */
61 #define EEH_PE_VF	(1 << 4)	/* VF PE     */
62 
63 #define EEH_PE_ISOLATED		(1 << 0)	/* Isolated PE		*/
64 #define EEH_PE_RECOVERING	(1 << 1)	/* Recovering PE	*/
65 #define EEH_PE_CFG_BLOCKED	(1 << 2)	/* Block config access	*/
66 #define EEH_PE_RESET		(1 << 3)	/* PE reset in progress */
67 
68 #define EEH_PE_KEEP		(1 << 8)	/* Keep PE on hotplug	*/
69 #define EEH_PE_CFG_RESTRICTED	(1 << 9)	/* Block config on error */
70 #define EEH_PE_REMOVED		(1 << 10)	/* Removed permanently	*/
71 #define EEH_PE_PRI_BUS		(1 << 11)	/* Cached primary bus   */
72 
73 struct eeh_pe {
74 	int type;			/* PE type: PHB/Bus/Device	*/
75 	int state;			/* PE EEH dependent mode	*/
76 	int addr;			/* PE configuration address	*/
77 	struct pci_controller *phb;	/* Associated PHB		*/
78 	struct pci_bus *bus;		/* Top PCI bus for bus PE	*/
79 	int check_count;		/* Times of ignored error	*/
80 	int freeze_count;		/* Times of froze up		*/
81 	time64_t tstamp;		/* Time on first-time freeze	*/
82 	int false_positives;		/* Times of reported #ff's	*/
83 	atomic_t pass_dev_cnt;		/* Count of passed through devs	*/
84 	struct eeh_pe *parent;		/* Parent PE			*/
85 	void *data;			/* PE auxillary data		*/
86 	struct list_head child_list;	/* List of PEs below this PE	*/
87 	struct list_head child;		/* Memb. child_list/eeh_phb_pe	*/
88 	struct list_head edevs;		/* List of eeh_dev in this PE	*/
89 
90 #ifdef CONFIG_STACKTRACE
91 	/*
92 	 * Saved stack trace. When we find a PE freeze in eeh_dev_check_failure
93 	 * the stack trace is saved here so we can print it in the recovery
94 	 * thread if it turns out to due to a real problem rather than
95 	 * a hot-remove.
96 	 *
97 	 * A max of 64 entries might be overkill, but it also might not be.
98 	 */
99 	unsigned long stack_trace[64];
100 	int trace_entries;
101 #endif /* CONFIG_STACKTRACE */
102 };
103 
104 #define eeh_pe_for_each_dev(pe, edev, tmp) \
105 		list_for_each_entry_safe(edev, tmp, &pe->edevs, entry)
106 
107 #define eeh_for_each_pe(root, pe) \
108 	for (pe = root; pe; pe = eeh_pe_next(pe, root))
109 
eeh_pe_passed(struct eeh_pe * pe)110 static inline bool eeh_pe_passed(struct eeh_pe *pe)
111 {
112 	return pe ? !!atomic_read(&pe->pass_dev_cnt) : false;
113 }
114 
115 /*
116  * The struct is used to trace EEH state for the associated
117  * PCI device node or PCI device. In future, it might
118  * represent PE as well so that the EEH device to form
119  * another tree except the currently existing tree of PCI
120  * buses and PCI devices
121  */
122 #define EEH_DEV_BRIDGE		(1 << 0)	/* PCI bridge		*/
123 #define EEH_DEV_ROOT_PORT	(1 << 1)	/* PCIe root port	*/
124 #define EEH_DEV_DS_PORT		(1 << 2)	/* Downstream port	*/
125 #define EEH_DEV_IRQ_DISABLED	(1 << 3)	/* Interrupt disabled	*/
126 #define EEH_DEV_DISCONNECTED	(1 << 4)	/* Removing from PE	*/
127 
128 #define EEH_DEV_NO_HANDLER	(1 << 8)	/* No error handler	*/
129 #define EEH_DEV_SYSFS		(1 << 9)	/* Sysfs created	*/
130 #define EEH_DEV_REMOVED		(1 << 10)	/* Removed permanently	*/
131 
132 struct eeh_dev {
133 	int mode;			/* EEH mode			*/
134 	int bdfn;			/* bdfn of device (for cfg ops) */
135 	struct pci_controller *controller;
136 	int pe_config_addr;		/* PE config address		*/
137 	u32 config_space[16];		/* Saved PCI config space	*/
138 	int pcix_cap;			/* Saved PCIx capability	*/
139 	int pcie_cap;			/* Saved PCIe capability	*/
140 	int aer_cap;			/* Saved AER capability		*/
141 	int af_cap;			/* Saved AF capability		*/
142 	struct eeh_pe *pe;		/* Associated PE		*/
143 	struct list_head entry;		/* Membership in eeh_pe.edevs	*/
144 	struct list_head rmv_entry;	/* Membership in rmv_list	*/
145 	struct pci_dn *pdn;		/* Associated PCI device node	*/
146 	struct pci_dev *pdev;		/* Associated PCI device	*/
147 	bool in_error;			/* Error flag for edev		*/
148 
149 	/* VF specific properties */
150 	struct pci_dev *physfn;		/* Associated SRIOV PF		*/
151 	int vf_index;			/* Index of this VF 		*/
152 };
153 
154 /* "fmt" must be a simple literal string */
155 #define EEH_EDEV_PRINT(level, edev, fmt, ...) \
156 	pr_##level("PCI %04x:%02x:%02x.%x#%04x: EEH: " fmt, \
157 	(edev)->controller->global_number, PCI_BUSNO((edev)->bdfn), \
158 	PCI_SLOT((edev)->bdfn), PCI_FUNC((edev)->bdfn), \
159 	((edev)->pe ? (edev)->pe_config_addr : 0xffff), ##__VA_ARGS__)
160 #define eeh_edev_dbg(edev, fmt, ...) EEH_EDEV_PRINT(debug, (edev), fmt, ##__VA_ARGS__)
161 #define eeh_edev_info(edev, fmt, ...) EEH_EDEV_PRINT(info, (edev), fmt, ##__VA_ARGS__)
162 #define eeh_edev_warn(edev, fmt, ...) EEH_EDEV_PRINT(warn, (edev), fmt, ##__VA_ARGS__)
163 #define eeh_edev_err(edev, fmt, ...) EEH_EDEV_PRINT(err, (edev), fmt, ##__VA_ARGS__)
164 
eeh_dev_to_pdn(struct eeh_dev * edev)165 static inline struct pci_dn *eeh_dev_to_pdn(struct eeh_dev *edev)
166 {
167 	return edev ? edev->pdn : NULL;
168 }
169 
eeh_dev_to_pci_dev(struct eeh_dev * edev)170 static inline struct pci_dev *eeh_dev_to_pci_dev(struct eeh_dev *edev)
171 {
172 	return edev ? edev->pdev : NULL;
173 }
174 
eeh_dev_to_pe(struct eeh_dev * edev)175 static inline struct eeh_pe *eeh_dev_to_pe(struct eeh_dev* edev)
176 {
177 	return edev ? edev->pe : NULL;
178 }
179 
180 /* Return values from eeh_ops::next_error */
181 enum {
182 	EEH_NEXT_ERR_NONE = 0,
183 	EEH_NEXT_ERR_INF,
184 	EEH_NEXT_ERR_FROZEN_PE,
185 	EEH_NEXT_ERR_FENCED_PHB,
186 	EEH_NEXT_ERR_DEAD_PHB,
187 	EEH_NEXT_ERR_DEAD_IOC
188 };
189 
190 /*
191  * The struct is used to trace the registered EEH operation
192  * callback functions. Actually, those operation callback
193  * functions are heavily platform dependent. That means the
194  * platform should register its own EEH operation callback
195  * functions before any EEH further operations.
196  */
197 #define EEH_OPT_DISABLE		0	/* EEH disable	*/
198 #define EEH_OPT_ENABLE		1	/* EEH enable	*/
199 #define EEH_OPT_THAW_MMIO	2	/* MMIO enable	*/
200 #define EEH_OPT_THAW_DMA	3	/* DMA enable	*/
201 #define EEH_OPT_FREEZE_PE	4	/* Freeze PE	*/
202 #define EEH_STATE_UNAVAILABLE	(1 << 0)	/* State unavailable	*/
203 #define EEH_STATE_NOT_SUPPORT	(1 << 1)	/* EEH not supported	*/
204 #define EEH_STATE_RESET_ACTIVE	(1 << 2)	/* Active reset		*/
205 #define EEH_STATE_MMIO_ACTIVE	(1 << 3)	/* Active MMIO		*/
206 #define EEH_STATE_DMA_ACTIVE	(1 << 4)	/* Active DMA		*/
207 #define EEH_STATE_MMIO_ENABLED	(1 << 5)	/* MMIO enabled		*/
208 #define EEH_STATE_DMA_ENABLED	(1 << 6)	/* DMA enabled		*/
209 #define EEH_RESET_DEACTIVATE	0	/* Deactivate the PE reset	*/
210 #define EEH_RESET_HOT		1	/* Hot reset			*/
211 #define EEH_RESET_FUNDAMENTAL	3	/* Fundamental reset		*/
212 #define EEH_LOG_TEMP		1	/* EEH temporary error log	*/
213 #define EEH_LOG_PERM		2	/* EEH permanent error log	*/
214 
215 struct eeh_ops {
216 	char *name;
217 	struct eeh_dev *(*probe)(struct pci_dev *pdev);
218 	int (*set_option)(struct eeh_pe *pe, int option);
219 	int (*get_state)(struct eeh_pe *pe, int *delay);
220 	int (*reset)(struct eeh_pe *pe, int option);
221 	int (*get_log)(struct eeh_pe *pe, int severity, char *drv_log, unsigned long len);
222 	int (*configure_bridge)(struct eeh_pe *pe);
223 	int (*err_inject)(struct eeh_pe *pe, int type, int func,
224 			  unsigned long addr, unsigned long mask);
225 	int (*read_config)(struct eeh_dev *edev, int where, int size, u32 *val);
226 	int (*write_config)(struct eeh_dev *edev, int where, int size, u32 val);
227 	int (*next_error)(struct eeh_pe **pe);
228 	int (*restore_config)(struct eeh_dev *edev);
229 	int (*notify_resume)(struct eeh_dev *edev);
230 };
231 
232 extern int eeh_subsystem_flags;
233 extern u32 eeh_max_freezes;
234 extern bool eeh_debugfs_no_recover;
235 extern struct eeh_ops *eeh_ops;
236 extern raw_spinlock_t confirm_error_lock;
237 
eeh_add_flag(int flag)238 static inline void eeh_add_flag(int flag)
239 {
240 	eeh_subsystem_flags |= flag;
241 }
242 
eeh_clear_flag(int flag)243 static inline void eeh_clear_flag(int flag)
244 {
245 	eeh_subsystem_flags &= ~flag;
246 }
247 
eeh_has_flag(int flag)248 static inline bool eeh_has_flag(int flag)
249 {
250         return !!(eeh_subsystem_flags & flag);
251 }
252 
eeh_enabled(void)253 static inline bool eeh_enabled(void)
254 {
255 	return eeh_has_flag(EEH_ENABLED) && !eeh_has_flag(EEH_FORCE_DISABLED);
256 }
257 
eeh_serialize_lock(unsigned long * flags)258 static inline void eeh_serialize_lock(unsigned long *flags)
259 {
260 	raw_spin_lock_irqsave(&confirm_error_lock, *flags);
261 }
262 
eeh_serialize_unlock(unsigned long flags)263 static inline void eeh_serialize_unlock(unsigned long flags)
264 {
265 	raw_spin_unlock_irqrestore(&confirm_error_lock, flags);
266 }
267 
eeh_state_active(int state)268 static inline bool eeh_state_active(int state)
269 {
270 	return (state & (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE))
271 	== (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE);
272 }
273 
274 typedef void (*eeh_edev_traverse_func)(struct eeh_dev *edev, void *flag);
275 typedef void *(*eeh_pe_traverse_func)(struct eeh_pe *pe, void *flag);
276 void eeh_set_pe_aux_size(int size);
277 int eeh_phb_pe_create(struct pci_controller *phb);
278 int eeh_wait_state(struct eeh_pe *pe, int max_wait);
279 struct eeh_pe *eeh_phb_pe_get(struct pci_controller *phb);
280 struct eeh_pe *eeh_pe_next(struct eeh_pe *pe, struct eeh_pe *root);
281 struct eeh_pe *eeh_pe_get(struct pci_controller *phb, int pe_no);
282 int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent);
283 int eeh_pe_tree_remove(struct eeh_dev *edev);
284 void eeh_pe_update_time_stamp(struct eeh_pe *pe);
285 void *eeh_pe_traverse(struct eeh_pe *root,
286 		      eeh_pe_traverse_func fn, void *flag);
287 void eeh_pe_dev_traverse(struct eeh_pe *root,
288 			 eeh_edev_traverse_func fn, void *flag);
289 void eeh_pe_restore_bars(struct eeh_pe *pe);
290 const char *eeh_pe_loc_get(struct eeh_pe *pe);
291 struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe);
292 
293 void eeh_show_enabled(void);
294 int __init eeh_init(struct eeh_ops *ops);
295 int eeh_check_failure(const volatile void __iomem *token);
296 int eeh_dev_check_failure(struct eeh_dev *edev);
297 void eeh_addr_cache_init(void);
298 void eeh_probe_device(struct pci_dev *pdev);
299 void eeh_remove_device(struct pci_dev *);
300 int eeh_unfreeze_pe(struct eeh_pe *pe);
301 int eeh_pe_reset_and_recover(struct eeh_pe *pe);
302 int eeh_dev_open(struct pci_dev *pdev);
303 void eeh_dev_release(struct pci_dev *pdev);
304 struct eeh_pe *eeh_iommu_group_to_pe(struct iommu_group *group);
305 int eeh_pe_set_option(struct eeh_pe *pe, int option);
306 int eeh_pe_get_state(struct eeh_pe *pe);
307 int eeh_pe_reset(struct eeh_pe *pe, int option, bool include_passed);
308 int eeh_pe_configure(struct eeh_pe *pe);
309 int eeh_pe_inject_err(struct eeh_pe *pe, int type, int func,
310 		      unsigned long addr, unsigned long mask);
311 
312 /**
313  * EEH_POSSIBLE_ERROR() -- test for possible MMIO failure.
314  *
315  * If this macro yields TRUE, the caller relays to eeh_check_failure()
316  * which does further tests out of line.
317  */
318 #define EEH_POSSIBLE_ERROR(val, type)	((val) == (type)~0 && eeh_enabled())
319 
320 /*
321  * Reads from a device which has been isolated by EEH will return
322  * all 1s.  This macro gives an all-1s value of the given size (in
323  * bytes: 1, 2, or 4) for comparing with the result of a read.
324  */
325 #define EEH_IO_ERROR_VALUE(size)	(~0U >> ((4 - (size)) * 8))
326 
327 #else /* !CONFIG_EEH */
328 
eeh_enabled(void)329 static inline bool eeh_enabled(void)
330 {
331         return false;
332 }
333 
eeh_show_enabled(void)334 static inline void eeh_show_enabled(void) { }
335 
eeh_dev_phb_init_dynamic(struct pci_controller * phb)336 static inline void eeh_dev_phb_init_dynamic(struct pci_controller *phb) { }
337 
eeh_check_failure(const volatile void __iomem * token)338 static inline int eeh_check_failure(const volatile void __iomem *token)
339 {
340 	return 0;
341 }
342 
343 #define eeh_dev_check_failure(x) (0)
344 
eeh_addr_cache_init(void)345 static inline void eeh_addr_cache_init(void) { }
346 
eeh_probe_device(struct pci_dev * dev)347 static inline void eeh_probe_device(struct pci_dev *dev) { }
348 
eeh_remove_device(struct pci_dev * dev)349 static inline void eeh_remove_device(struct pci_dev *dev) { }
350 
351 #define EEH_POSSIBLE_ERROR(val, type) (0)
352 #define EEH_IO_ERROR_VALUE(size) (-1UL)
eeh_phb_pe_create(struct pci_controller * phb)353 static inline int eeh_phb_pe_create(struct pci_controller *phb) { return 0; }
354 #endif /* CONFIG_EEH */
355 
356 #if defined(CONFIG_PPC_PSERIES) && defined(CONFIG_EEH)
357 void pseries_eeh_init_edev(struct pci_dn *pdn);
358 void pseries_eeh_init_edev_recursive(struct pci_dn *pdn);
359 #else
pseries_eeh_add_device_early(struct pci_dn * pdn)360 static inline void pseries_eeh_add_device_early(struct pci_dn *pdn) { }
pseries_eeh_add_device_tree_early(struct pci_dn * pdn)361 static inline void pseries_eeh_add_device_tree_early(struct pci_dn *pdn) { }
362 #endif
363 
364 #ifdef CONFIG_PPC64
365 /*
366  * MMIO read/write operations with EEH support.
367  */
eeh_readb(const volatile void __iomem * addr)368 static inline u8 eeh_readb(const volatile void __iomem *addr)
369 {
370 	u8 val = in_8(addr);
371 	if (EEH_POSSIBLE_ERROR(val, u8))
372 		eeh_check_failure(addr);
373 	return val;
374 }
375 
eeh_readw(const volatile void __iomem * addr)376 static inline u16 eeh_readw(const volatile void __iomem *addr)
377 {
378 	u16 val = in_le16(addr);
379 	if (EEH_POSSIBLE_ERROR(val, u16))
380 		eeh_check_failure(addr);
381 	return val;
382 }
383 
eeh_readl(const volatile void __iomem * addr)384 static inline u32 eeh_readl(const volatile void __iomem *addr)
385 {
386 	u32 val = in_le32(addr);
387 	if (EEH_POSSIBLE_ERROR(val, u32))
388 		eeh_check_failure(addr);
389 	return val;
390 }
391 
eeh_readq(const volatile void __iomem * addr)392 static inline u64 eeh_readq(const volatile void __iomem *addr)
393 {
394 	u64 val = in_le64(addr);
395 	if (EEH_POSSIBLE_ERROR(val, u64))
396 		eeh_check_failure(addr);
397 	return val;
398 }
399 
eeh_readw_be(const volatile void __iomem * addr)400 static inline u16 eeh_readw_be(const volatile void __iomem *addr)
401 {
402 	u16 val = in_be16(addr);
403 	if (EEH_POSSIBLE_ERROR(val, u16))
404 		eeh_check_failure(addr);
405 	return val;
406 }
407 
eeh_readl_be(const volatile void __iomem * addr)408 static inline u32 eeh_readl_be(const volatile void __iomem *addr)
409 {
410 	u32 val = in_be32(addr);
411 	if (EEH_POSSIBLE_ERROR(val, u32))
412 		eeh_check_failure(addr);
413 	return val;
414 }
415 
eeh_readq_be(const volatile void __iomem * addr)416 static inline u64 eeh_readq_be(const volatile void __iomem *addr)
417 {
418 	u64 val = in_be64(addr);
419 	if (EEH_POSSIBLE_ERROR(val, u64))
420 		eeh_check_failure(addr);
421 	return val;
422 }
423 
eeh_memcpy_fromio(void * dest,const volatile void __iomem * src,unsigned long n)424 static inline void eeh_memcpy_fromio(void *dest, const
425 				     volatile void __iomem *src,
426 				     unsigned long n)
427 {
428 	_memcpy_fromio(dest, src, n);
429 
430 	/* Look for ffff's here at dest[n].  Assume that at least 4 bytes
431 	 * were copied. Check all four bytes.
432 	 */
433 	if (n >= 4 && EEH_POSSIBLE_ERROR(*((u32 *)(dest + n - 4)), u32))
434 		eeh_check_failure(src);
435 }
436 
437 /* in-string eeh macros */
eeh_readsb(const volatile void __iomem * addr,void * buf,int ns)438 static inline void eeh_readsb(const volatile void __iomem *addr, void * buf,
439 			      int ns)
440 {
441 	_insb(addr, buf, ns);
442 	if (EEH_POSSIBLE_ERROR((*(((u8*)buf)+ns-1)), u8))
443 		eeh_check_failure(addr);
444 }
445 
eeh_readsw(const volatile void __iomem * addr,void * buf,int ns)446 static inline void eeh_readsw(const volatile void __iomem *addr, void * buf,
447 			      int ns)
448 {
449 	_insw(addr, buf, ns);
450 	if (EEH_POSSIBLE_ERROR((*(((u16*)buf)+ns-1)), u16))
451 		eeh_check_failure(addr);
452 }
453 
eeh_readsl(const volatile void __iomem * addr,void * buf,int nl)454 static inline void eeh_readsl(const volatile void __iomem *addr, void * buf,
455 			      int nl)
456 {
457 	_insl(addr, buf, nl);
458 	if (EEH_POSSIBLE_ERROR((*(((u32*)buf)+nl-1)), u32))
459 		eeh_check_failure(addr);
460 }
461 
462 
463 void eeh_cache_debugfs_init(void);
464 
465 #endif /* CONFIG_PPC64 */
466 #endif /* __KERNEL__ */
467 #endif /* _POWERPC_EEH_H */
468