xref: /openbmc/linux/arch/powerpc/kernel/eeh_sysfs.c (revision 2c684d89)
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, S_IRUGO, eeh_show_##_name, NULL);
52 
53 EEH_SHOW_ATTR(eeh_mode,            mode,            "0x%x");
54 EEH_SHOW_ATTR(eeh_config_addr,     config_addr,     "0x%x");
55 EEH_SHOW_ATTR(eeh_pe_config_addr,  pe_config_addr,  "0x%x");
56 
57 static ssize_t eeh_pe_state_show(struct device *dev,
58 				 struct device_attribute *attr, char *buf)
59 {
60 	struct pci_dev *pdev = to_pci_dev(dev);
61 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
62 	int state;
63 
64 	if (!edev || !edev->pe)
65 		return -ENODEV;
66 
67 	state = eeh_ops->get_state(edev->pe, NULL);
68 	return sprintf(buf, "0x%08x 0x%08x\n",
69 		       state, edev->pe->state);
70 }
71 
72 static ssize_t eeh_pe_state_store(struct device *dev,
73 				  struct device_attribute *attr,
74 				  const char *buf, size_t count)
75 {
76 	struct pci_dev *pdev = to_pci_dev(dev);
77 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
78 
79 	if (!edev || !edev->pe)
80 		return -ENODEV;
81 
82 	/* Nothing to do if it's not frozen */
83 	if (!(edev->pe->state & EEH_PE_ISOLATED))
84 		return count;
85 
86 	if (eeh_unfreeze_pe(edev->pe, true))
87 		return -EIO;
88 
89 	return count;
90 }
91 
92 static DEVICE_ATTR_RW(eeh_pe_state);
93 
94 void eeh_sysfs_add_device(struct pci_dev *pdev)
95 {
96 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
97 	int rc=0;
98 
99 	if (!eeh_enabled())
100 		return;
101 
102 	if (edev && (edev->mode & EEH_DEV_SYSFS))
103 		return;
104 
105 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode);
106 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_config_addr);
107 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
108 	rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_state);
109 
110 	if (rc)
111 		pr_warn("EEH: Unable to create sysfs entries\n");
112 	else if (edev)
113 		edev->mode |= EEH_DEV_SYSFS;
114 }
115 
116 void eeh_sysfs_remove_device(struct pci_dev *pdev)
117 {
118 	struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
119 
120 	/*
121 	 * The parent directory might have been removed. We needn't
122 	 * continue for that case.
123 	 */
124 	if (!pdev->dev.kobj.sd) {
125 		if (edev)
126 			edev->mode &= ~EEH_DEV_SYSFS;
127 		return;
128 	}
129 
130 	device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
131 	device_remove_file(&pdev->dev, &dev_attr_eeh_config_addr);
132 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
133 	device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
134 
135 	if (edev)
136 		edev->mode &= ~EEH_DEV_SYSFS;
137 }
138