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/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 }