xref: /openbmc/linux/arch/powerpc/kernel/eeh_sysfs.c (revision b830f94f)
1 /*
2  * Sysfs entries for PCI Error Recovery for PAPR-compliant platform.
3  * Copyright IBM Corporation 2007
4  * Copyright Linas Vepstas <linas@austin.ibm.com> 2007
5  *
6  * All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or (at
11  * your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
24  */
25 #include <linux/pci.h>
26 #include <linux/stat.h>
27 #include <asm/ppc-pci.h>
28 #include <asm/pci-bridge.h>
29 
30 /**
31  * EEH_SHOW_ATTR -- Create sysfs entry for eeh statistic
32  * @_name: name of file in sysfs directory
33  * @_memb: name of member in struct pci_dn to access
34  * @_format: printf format for display
35  *
36  * All of the attributes look very similar, so just
37  * auto-gen a cut-n-paste routine to display them.
38  */
39 #define EEH_SHOW_ATTR(_name,_memb,_format)               \
40 static ssize_t eeh_show_##_name(struct device *dev,      \
41 		struct device_attribute *attr, char *buf)          \
42 {                                                        \
43 	struct pci_dev *pdev = to_pci_dev(dev);               \
44 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);      \
45 	                                                      \
46 	if (!edev)                                            \
47 		return 0;                                     \
48 	                                                      \
49 	return sprintf(buf, _format "\n", edev->_memb);       \
50 }                                                        \
51 static DEVICE_ATTR(_name, 0444, eeh_show_##_name, NULL);
52 
53 EEH_SHOW_ATTR(eeh_mode,            mode,            "0x%x");
54 EEH_SHOW_ATTR(eeh_pe_config_addr,  pe_config_addr,  "0x%x");
55 
56 static ssize_t eeh_pe_state_show(struct device *dev,
57 				 struct device_attribute *attr, char *buf)
58 {
59 	struct pci_dev *pdev = to_pci_dev(dev);
60 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
61 	int state;
62 
63 	if (!edev || !edev->pe)
64 		return -ENODEV;
65 
66 	state = eeh_ops->get_state(edev->pe, NULL);
67 	return sprintf(buf, "0x%08x 0x%08x\n",
68 		       state, edev->pe->state);
69 }
70 
71 static ssize_t eeh_pe_state_store(struct device *dev,
72 				  struct device_attribute *attr,
73 				  const char *buf, size_t count)
74 {
75 	struct pci_dev *pdev = to_pci_dev(dev);
76 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
77 
78 	if (!edev || !edev->pe)
79 		return -ENODEV;
80 
81 	/* Nothing to do if it's not frozen */
82 	if (!(edev->pe->state & EEH_PE_ISOLATED))
83 		return count;
84 
85 	if (eeh_unfreeze_pe(edev->pe))
86 		return -EIO;
87 	eeh_pe_state_clear(edev->pe, EEH_PE_ISOLATED, true);
88 
89 	return count;
90 }
91 
92 static DEVICE_ATTR_RW(eeh_pe_state);
93 
94 #ifdef CONFIG_PCI_IOV
95 static ssize_t eeh_notify_resume_show(struct device *dev,
96 				      struct device_attribute *attr, char *buf)
97 {
98 	struct pci_dev *pdev = to_pci_dev(dev);
99 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
100 	struct pci_dn *pdn = pci_get_pdn(pdev);
101 
102 	if (!edev || !edev->pe)
103 		return -ENODEV;
104 
105 	pdn = pci_get_pdn(pdev);
106 	return sprintf(buf, "%d\n", pdn->last_allow_rc);
107 }
108 
109 static ssize_t eeh_notify_resume_store(struct device *dev,
110 				       struct device_attribute *attr,
111 				       const char *buf, size_t count)
112 {
113 	struct pci_dev *pdev = to_pci_dev(dev);
114 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
115 
116 	if (!edev || !edev->pe || !eeh_ops->notify_resume)
117 		return -ENODEV;
118 
119 	if (eeh_ops->notify_resume(pci_get_pdn(pdev)))
120 		return -EIO;
121 
122 	return count;
123 }
124 static DEVICE_ATTR_RW(eeh_notify_resume);
125 
126 static int eeh_notify_resume_add(struct pci_dev *pdev)
127 {
128 	struct device_node *np;
129 	int rc = 0;
130 
131 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
132 
133 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
134 		rc = device_create_file(&pdev->dev, &dev_attr_eeh_notify_resume);
135 
136 	return rc;
137 }
138 
139 static void eeh_notify_resume_remove(struct pci_dev *pdev)
140 {
141 	struct device_node *np;
142 
143 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
144 
145 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
146 		device_remove_file(&pdev->dev, &dev_attr_eeh_notify_resume);
147 }
148 #else
149 static inline int eeh_notify_resume_add(struct pci_dev *pdev) { return 0; }
150 static inline void eeh_notify_resume_remove(struct pci_dev *pdev) { }
151 #endif /* CONFIG_PCI_IOV */
152 
153 void eeh_sysfs_add_device(struct pci_dev *pdev)
154 {
155 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
156 	int rc=0;
157 
158 	if (!eeh_enabled())
159 		return;
160 
161 	if (edev && (edev->mode & EEH_DEV_SYSFS))
162 		return;
163 
164 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode);
165 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
166 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_state);
167 	rc += eeh_notify_resume_add(pdev);
168 
169 	if (rc)
170 		pr_warn("EEH: Unable to create sysfs entries\n");
171 	else if (edev)
172 		edev->mode |= EEH_DEV_SYSFS;
173 }
174 
175 void eeh_sysfs_remove_device(struct pci_dev *pdev)
176 {
177 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
178 
179 	/*
180 	 * The parent directory might have been removed. We needn't
181 	 * continue for that case.
182 	 */
183 	if (!pdev->dev.kobj.sd) {
184 		if (edev)
185 			edev->mode &= ~EEH_DEV_SYSFS;
186 		return;
187 	}
188 
189 	device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
190 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
191 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
192 
193 	eeh_notify_resume_remove(pdev);
194 
195 	if (edev)
196 		edev->mode &= ~EEH_DEV_SYSFS;
197 }
198