xref: /linux/arch/powerpc/kernel/eeh_sysfs.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
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/of.h>
10 #include <linux/pci.h>
11 #include <linux/stat.h>
12 #include <asm/ppc-pci.h>
13 #include <asm/pci-bridge.h>
14 
15 /**
16  * EEH_SHOW_ATTR -- Create sysfs entry for eeh statistic
17  * @_name: name of file in sysfs directory
18  * @_memb: name of member in struct eeh_dev to access
19  * @_format: printf format for display
20  *
21  * All of the attributes look very similar, so just
22  * auto-gen a cut-n-paste routine to display them.
23  */
24 #define EEH_SHOW_ATTR(_name,_memb,_format)               \
25 static ssize_t eeh_show_##_name(struct device *dev,      \
26 		struct device_attribute *attr, char *buf)          \
27 {                                                        \
28 	struct pci_dev *pdev = to_pci_dev(dev);               \
29 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);      \
30 	                                                      \
31 	if (!edev)                                            \
32 		return 0;                                     \
33 	                                                      \
34 	return sprintf(buf, _format "\n", edev->_memb);       \
35 }                                                        \
36 static DEVICE_ATTR(_name, 0444, eeh_show_##_name, NULL);
37 
38 EEH_SHOW_ATTR(eeh_mode,            mode,            "0x%x");
39 EEH_SHOW_ATTR(eeh_pe_config_addr,  pe_config_addr,  "0x%x");
40 
41 static ssize_t eeh_pe_state_show(struct device *dev,
42 				 struct device_attribute *attr, char *buf)
43 {
44 	struct pci_dev *pdev = to_pci_dev(dev);
45 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
46 	int state;
47 
48 	if (!edev || !edev->pe)
49 		return -ENODEV;
50 
51 	state = eeh_ops->get_state(edev->pe, NULL);
52 	return sprintf(buf, "0x%08x 0x%08x\n",
53 		       state, edev->pe->state);
54 }
55 
56 static ssize_t eeh_pe_state_store(struct device *dev,
57 				  struct device_attribute *attr,
58 				  const char *buf, size_t count)
59 {
60 	struct pci_dev *pdev = to_pci_dev(dev);
61 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
62 
63 	if (!edev || !edev->pe)
64 		return -ENODEV;
65 
66 	/* Nothing to do if it's not frozen */
67 	if (!(edev->pe->state & EEH_PE_ISOLATED))
68 		return count;
69 
70 	if (eeh_unfreeze_pe(edev->pe))
71 		return -EIO;
72 	eeh_pe_state_clear(edev->pe, EEH_PE_ISOLATED, true);
73 
74 	return count;
75 }
76 
77 static DEVICE_ATTR_RW(eeh_pe_state);
78 
79 #if defined(CONFIG_PCI_IOV) && defined(CONFIG_PPC_PSERIES)
80 static ssize_t eeh_notify_resume_show(struct device *dev,
81 				      struct device_attribute *attr, char *buf)
82 {
83 	struct pci_dev *pdev = to_pci_dev(dev);
84 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
85 	struct pci_dn *pdn = pci_get_pdn(pdev);
86 
87 	if (!edev || !edev->pe)
88 		return -ENODEV;
89 
90 	return sprintf(buf, "%d\n", pdn->last_allow_rc);
91 }
92 
93 static ssize_t eeh_notify_resume_store(struct device *dev,
94 				       struct device_attribute *attr,
95 				       const char *buf, size_t count)
96 {
97 	struct pci_dev *pdev = to_pci_dev(dev);
98 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
99 
100 	if (!edev || !edev->pe || !eeh_ops->notify_resume)
101 		return -ENODEV;
102 
103 	if (eeh_ops->notify_resume(edev))
104 		return -EIO;
105 
106 	return count;
107 }
108 static DEVICE_ATTR_RW(eeh_notify_resume);
109 
110 static int eeh_notify_resume_add(struct pci_dev *pdev)
111 {
112 	struct device_node *np;
113 	int rc = 0;
114 
115 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
116 
117 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
118 		rc = device_create_file(&pdev->dev, &dev_attr_eeh_notify_resume);
119 
120 	return rc;
121 }
122 
123 static void eeh_notify_resume_remove(struct pci_dev *pdev)
124 {
125 	struct device_node *np;
126 
127 	np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
128 
129 	if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
130 		device_remove_file(&pdev->dev, &dev_attr_eeh_notify_resume);
131 }
132 #else
133 static inline int eeh_notify_resume_add(struct pci_dev *pdev) { return 0; }
134 static inline void eeh_notify_resume_remove(struct pci_dev *pdev) { }
135 #endif /* CONFIG_PCI_IOV && CONFIG PPC_PSERIES*/
136 
137 void eeh_sysfs_add_device(struct pci_dev *pdev)
138 {
139 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
140 	int rc=0;
141 
142 	if (!eeh_enabled())
143 		return;
144 
145 	if (edev && (edev->mode & EEH_DEV_SYSFS))
146 		return;
147 
148 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode);
149 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
150 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_state);
151 	rc += eeh_notify_resume_add(pdev);
152 
153 	if (rc)
154 		pr_warn("EEH: Unable to create sysfs entries\n");
155 	else if (edev)
156 		edev->mode |= EEH_DEV_SYSFS;
157 }
158 
159 void eeh_sysfs_remove_device(struct pci_dev *pdev)
160 {
161 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
162 
163 	if (!edev) {
164 		WARN_ON(eeh_enabled());
165 		return;
166 	}
167 
168 	edev->mode &= ~EEH_DEV_SYSFS;
169 
170 	/*
171 	 * The parent directory might have been removed. We needn't
172 	 * continue for that case.
173 	 */
174 	if (!pdev->dev.kobj.sd)
175 		return;
176 
177 	device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
178 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
179 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
180 
181 	eeh_notify_resume_remove(pdev);
182 }
183