xref: /openbmc/linux/arch/powerpc/kernel/eeh_sysfs.c (revision b5265c81)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Sysfs entries for PCI Error Recovery for PAPR-compliant platform.
4  * Copyright IBM Corporation 2007
5  * Copyright Linas Vepstas <linas@austin.ibm.com> 2007
6  *
7  * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
8  */
9 #include <linux/pci.h>
10 #include <linux/stat.h>
11 #include <asm/ppc-pci.h>
12 #include <asm/pci-bridge.h>
13 
14 /**
15  * EEH_SHOW_ATTR -- Create sysfs entry for eeh statistic
16  * @_name: name of file in sysfs directory
17  * @_memb: name of member in struct eeh_dev to access
18  * @_format: printf format for display
19  *
20  * All of the attributes look very similar, so just
21  * auto-gen a cut-n-paste routine to display them.
22  */
23 #define EEH_SHOW_ATTR(_name,_memb,_format)               \
24 static ssize_t eeh_show_##_name(struct device *dev,      \
25 		struct device_attribute *attr, char *buf)          \
26 {                                                        \
27 	struct pci_dev *pdev = to_pci_dev(dev);               \
28 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);      \
29 	                                                      \
30 	if (!edev)                                            \
31 		return 0;                                     \
32 	                                                      \
33 	return sprintf(buf, _format "\n", edev->_memb);       \
34 }                                                        \
35 static DEVICE_ATTR(_name, 0444, eeh_show_##_name, NULL);
36 
37 EEH_SHOW_ATTR(eeh_mode,            mode,            "0x%x");
38 EEH_SHOW_ATTR(eeh_pe_config_addr,  pe_config_addr,  "0x%x");
39 
40 static ssize_t eeh_pe_state_show(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 	int state;
46 
47 	if (!edev || !edev->pe)
48 		return -ENODEV;
49 
50 	state = eeh_ops->get_state(edev->pe, NULL);
51 	return sprintf(buf, "0x%08x 0x%08x\n",
52 		       state, edev->pe->state);
53 }
54 
55 static ssize_t eeh_pe_state_store(struct device *dev,
56 				  struct device_attribute *attr,
57 				  const char *buf, size_t count)
58 {
59 	struct pci_dev *pdev = to_pci_dev(dev);
60 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
61 
62 	if (!edev || !edev->pe)
63 		return -ENODEV;
64 
65 	/* Nothing to do if it's not frozen */
66 	if (!(edev->pe->state & EEH_PE_ISOLATED))
67 		return count;
68 
69 	if (eeh_unfreeze_pe(edev->pe))
70 		return -EIO;
71 	eeh_pe_state_clear(edev->pe, EEH_PE_ISOLATED, true);
72 
73 	return count;
74 }
75 
76 static DEVICE_ATTR_RW(eeh_pe_state);
77 
78 #if defined(CONFIG_PCI_IOV) && defined(CONFIG_PPC_PSERIES)
79 static ssize_t eeh_notify_resume_show(struct device *dev,
80 				      struct device_attribute *attr, char *buf)
81 {
82 	struct pci_dev *pdev = to_pci_dev(dev);
83 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
84 	struct pci_dn *pdn = pci_get_pdn(pdev);
85 
86 	if (!edev || !edev->pe)
87 		return -ENODEV;
88 
89 	return sprintf(buf, "%d\n", pdn->last_allow_rc);
90 }
91 
92 static ssize_t eeh_notify_resume_store(struct device *dev,
93 				       struct device_attribute *attr,
94 				       const char *buf, size_t count)
95 {
96 	struct pci_dev *pdev = to_pci_dev(dev);
97 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
98 
99 	if (!edev || !edev->pe || !eeh_ops->notify_resume)
100 		return -ENODEV;
101 
102 	if (eeh_ops->notify_resume(pci_get_pdn(pdev)))
103 		return -EIO;
104 
105 	return count;
106 }
107 static DEVICE_ATTR_RW(eeh_notify_resume);
108 
109 static int eeh_notify_resume_add(struct pci_dev *pdev)
110 {
111 	struct device_node *np;
112 	int rc = 0;
113 
114 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
115 
116 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
117 		rc = device_create_file(&pdev->dev, &dev_attr_eeh_notify_resume);
118 
119 	return rc;
120 }
121 
122 static void eeh_notify_resume_remove(struct pci_dev *pdev)
123 {
124 	struct device_node *np;
125 
126 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
127 
128 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
129 		device_remove_file(&pdev->dev, &dev_attr_eeh_notify_resume);
130 }
131 #else
132 static inline int eeh_notify_resume_add(struct pci_dev *pdev) { return 0; }
133 static inline void eeh_notify_resume_remove(struct pci_dev *pdev) { }
134 #endif /* CONFIG_PCI_IOV && CONFIG PPC_PSERIES*/
135 
136 void eeh_sysfs_add_device(struct pci_dev *pdev)
137 {
138 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
139 	int rc=0;
140 
141 	if (!eeh_enabled())
142 		return;
143 
144 	if (edev && (edev->mode & EEH_DEV_SYSFS))
145 		return;
146 
147 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode);
148 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
149 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_state);
150 	rc += eeh_notify_resume_add(pdev);
151 
152 	if (rc)
153 		pr_warn("EEH: Unable to create sysfs entries\n");
154 	else if (edev)
155 		edev->mode |= EEH_DEV_SYSFS;
156 }
157 
158 void eeh_sysfs_remove_device(struct pci_dev *pdev)
159 {
160 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
161 
162 	if (!edev) {
163 		WARN_ON(eeh_enabled());
164 		return;
165 	}
166 
167 	edev->mode &= ~EEH_DEV_SYSFS;
168 
169 	/*
170 	 * The parent directory might have been removed. We needn't
171 	 * continue for that case.
172 	 */
173 	if (!pdev->dev.kobj.sd)
174 		return;
175 
176 	device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
177 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
178 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
179 
180 	eeh_notify_resume_remove(pdev);
181 }
182