arch/powerpc/kernel/eeh_sysfs.c

   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 }