1 /*
2  * eeh.h
3  * Copyright (C) 2001  Dave Engebretsen & Todd Inglett IBM Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
18  */
19 
20 #ifndef _POWERPC_EEH_H
21 #define _POWERPC_EEH_H
22 #ifdef __KERNEL__
23 
24 #include <linux/init.h>
25 #include <linux/list.h>
26 #include <linux/string.h>
27 
28 struct pci_dev;
29 struct pci_bus;
30 struct device_node;
31 
32 #ifdef CONFIG_EEH
33 
34 extern int eeh_subsystem_enabled;
35 
36 /* Values for eeh_mode bits in device_node */
37 #define EEH_MODE_SUPPORTED     (1<<0)
38 #define EEH_MODE_NOCHECK       (1<<1)
39 #define EEH_MODE_ISOLATED      (1<<2)
40 #define EEH_MODE_RECOVERING    (1<<3)
41 #define EEH_MODE_IRQ_DISABLED  (1<<4)
42 
43 /* Max number of EEH freezes allowed before we consider the device
44  * to be permanently disabled. */
45 #define EEH_MAX_ALLOWED_FREEZES 5
46 
47 void __init eeh_init(void);
48 unsigned long eeh_check_failure(const volatile void __iomem *token,
49 				unsigned long val);
50 int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev);
51 void __init pci_addr_cache_build(void);
52 
53 /**
54  * eeh_add_device_early
55  * eeh_add_device_late
56  *
57  * Perform eeh initialization for devices added after boot.
58  * Call eeh_add_device_early before doing any i/o to the
59  * device (including config space i/o).  Call eeh_add_device_late
60  * to finish the eeh setup for this device.
61  */
62 void eeh_add_device_tree_early(struct device_node *);
63 void eeh_add_device_tree_late(struct pci_bus *);
64 
65 /**
66  * eeh_remove_device_recursive - undo EEH for device & children.
67  * @dev: pci device to be removed
68  *
69  * As above, this removes the device; it also removes child
70  * pci devices as well.
71  */
72 void eeh_remove_bus_device(struct pci_dev *);
73 
74 /**
75  * EEH_POSSIBLE_ERROR() -- test for possible MMIO failure.
76  *
77  * If this macro yields TRUE, the caller relays to eeh_check_failure()
78  * which does further tests out of line.
79  */
80 #define EEH_POSSIBLE_ERROR(val, type)	((val) == (type)~0 && eeh_subsystem_enabled)
81 
82 /*
83  * Reads from a device which has been isolated by EEH will return
84  * all 1s.  This macro gives an all-1s value of the given size (in
85  * bytes: 1, 2, or 4) for comparing with the result of a read.
86  */
87 #define EEH_IO_ERROR_VALUE(size)	(~0U >> ((4 - (size)) * 8))
88 
89 #else /* !CONFIG_EEH */
eeh_init(void)90 static inline void eeh_init(void) { }
91 
eeh_check_failure(const volatile void __iomem * token,unsigned long val)92 static inline unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val)
93 {
94 	return val;
95 }
96 
eeh_dn_check_failure(struct device_node * dn,struct pci_dev * dev)97 static inline int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev)
98 {
99 	return 0;
100 }
101 
pci_addr_cache_build(void)102 static inline void pci_addr_cache_build(void) { }
103 
eeh_add_device_tree_early(struct device_node * dn)104 static inline void eeh_add_device_tree_early(struct device_node *dn) { }
105 
eeh_add_device_tree_late(struct pci_bus * bus)106 static inline void eeh_add_device_tree_late(struct pci_bus *bus) { }
107 
eeh_remove_bus_device(struct pci_dev * dev)108 static inline void eeh_remove_bus_device(struct pci_dev *dev) { }
109 #define EEH_POSSIBLE_ERROR(val, type) (0)
110 #define EEH_IO_ERROR_VALUE(size) (-1UL)
111 #endif /* CONFIG_EEH */
112 
113 #ifdef CONFIG_PPC64
114 /*
115  * MMIO read/write operations with EEH support.
116  */
eeh_readb(const volatile void __iomem * addr)117 static inline u8 eeh_readb(const volatile void __iomem *addr)
118 {
119 	u8 val = in_8(addr);
120 	if (EEH_POSSIBLE_ERROR(val, u8))
121 		return eeh_check_failure(addr, val);
122 	return val;
123 }
124 
eeh_readw(const volatile void __iomem * addr)125 static inline u16 eeh_readw(const volatile void __iomem *addr)
126 {
127 	u16 val = in_le16(addr);
128 	if (EEH_POSSIBLE_ERROR(val, u16))
129 		return eeh_check_failure(addr, val);
130 	return val;
131 }
132 
eeh_readl(const volatile void __iomem * addr)133 static inline u32 eeh_readl(const volatile void __iomem *addr)
134 {
135 	u32 val = in_le32(addr);
136 	if (EEH_POSSIBLE_ERROR(val, u32))
137 		return eeh_check_failure(addr, val);
138 	return val;
139 }
140 
eeh_readq(const volatile void __iomem * addr)141 static inline u64 eeh_readq(const volatile void __iomem *addr)
142 {
143 	u64 val = in_le64(addr);
144 	if (EEH_POSSIBLE_ERROR(val, u64))
145 		return eeh_check_failure(addr, val);
146 	return val;
147 }
148 
eeh_readw_be(const volatile void __iomem * addr)149 static inline u16 eeh_readw_be(const volatile void __iomem *addr)
150 {
151 	u16 val = in_be16(addr);
152 	if (EEH_POSSIBLE_ERROR(val, u16))
153 		return eeh_check_failure(addr, val);
154 	return val;
155 }
156 
eeh_readl_be(const volatile void __iomem * addr)157 static inline u32 eeh_readl_be(const volatile void __iomem *addr)
158 {
159 	u32 val = in_be32(addr);
160 	if (EEH_POSSIBLE_ERROR(val, u32))
161 		return eeh_check_failure(addr, val);
162 	return val;
163 }
164 
eeh_readq_be(const volatile void __iomem * addr)165 static inline u64 eeh_readq_be(const volatile void __iomem *addr)
166 {
167 	u64 val = in_be64(addr);
168 	if (EEH_POSSIBLE_ERROR(val, u64))
169 		return eeh_check_failure(addr, val);
170 	return val;
171 }
172 
eeh_memcpy_fromio(void * dest,const volatile void __iomem * src,unsigned long n)173 static inline void eeh_memcpy_fromio(void *dest, const
174 				     volatile void __iomem *src,
175 				     unsigned long n)
176 {
177 	_memcpy_fromio(dest, src, n);
178 
179 	/* Look for ffff's here at dest[n].  Assume that at least 4 bytes
180 	 * were copied. Check all four bytes.
181 	 */
182 	if (n >= 4 && EEH_POSSIBLE_ERROR(*((u32 *)(dest + n - 4)), u32))
183 		eeh_check_failure(src, *((u32 *)(dest + n - 4)));
184 }
185 
186 /* in-string eeh macros */
eeh_readsb(const volatile void __iomem * addr,void * buf,int ns)187 static inline void eeh_readsb(const volatile void __iomem *addr, void * buf,
188 			      int ns)
189 {
190 	_insb(addr, buf, ns);
191 	if (EEH_POSSIBLE_ERROR((*(((u8*)buf)+ns-1)), u8))
192 		eeh_check_failure(addr, *(u8*)buf);
193 }
194 
eeh_readsw(const volatile void __iomem * addr,void * buf,int ns)195 static inline void eeh_readsw(const volatile void __iomem *addr, void * buf,
196 			      int ns)
197 {
198 	_insw(addr, buf, ns);
199 	if (EEH_POSSIBLE_ERROR((*(((u16*)buf)+ns-1)), u16))
200 		eeh_check_failure(addr, *(u16*)buf);
201 }
202 
eeh_readsl(const volatile void __iomem * addr,void * buf,int nl)203 static inline void eeh_readsl(const volatile void __iomem *addr, void * buf,
204 			      int nl)
205 {
206 	_insl(addr, buf, nl);
207 	if (EEH_POSSIBLE_ERROR((*(((u32*)buf)+nl-1)), u32))
208 		eeh_check_failure(addr, *(u32*)buf);
209 }
210 
211 #endif /* CONFIG_PPC64 */
212 #endif /* __KERNEL__ */
213 #endif /* _POWERPC_EEH_H */
214