powerpc/kernel/eeh_sysfs.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Sysfs entries for PCI Error Recovery for PAPR-compliant platform.
0004  * Copyright IBM Corporation 2007
0005  * Copyright Linas Vepstas <linas@austin.ibm.com> 2007
0006  *
0007  * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
0008  */
0009 #include <linux/of.h>
0010 #include <linux/pci.h>
0011 #include <linux/stat.h>
0012 #include <asm/ppc-pci.h>
0013 #include <asm/pci-bridge.h>
0014
0015 /**
0016  * EEH_SHOW_ATTR -- Create sysfs entry for eeh statistic
0017  * @_name: name of file in sysfs directory
0018  * @_memb: name of member in struct eeh_dev to access
0019  * @_format: printf format for display
0020  *
0021  * All of the attributes look very similar, so just
0022  * auto-gen a cut-n-paste routine to display them.
0023  */
0024 #define EEH_SHOW_ATTR(_name,_memb,_format)               \
0025 static ssize_t eeh_show_##_name(struct device *dev,      \
0026         struct device_attribute *attr, char *buf)          \
0027 {                                                        \
0028     struct pci_dev *pdev = to_pci_dev(dev);               \
0029     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);      \
0030                                                           \
0031     if (!edev)                                            \
0032         return 0;                                     \
0033                                                           \
0034     return sprintf(buf, _format "\n", edev->_memb);       \
0035 }                                                        \
0036 static DEVICE_ATTR(_name, 0444, eeh_show_##_name, NULL);
0037
0038 EEH_SHOW_ATTR(eeh_mode,            mode,            "0x%x");
0039 EEH_SHOW_ATTR(eeh_pe_config_addr,  pe_config_addr,  "0x%x");
0040
0041 static ssize_t eeh_pe_state_show(struct device *dev,
0042                  struct device_attribute *attr, char *buf)
0043 {
0044     struct pci_dev *pdev = to_pci_dev(dev);
0045     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0046     int state;
0047
0048     if (!edev || !edev->pe)
0049         return -ENODEV;
0050
0051     state = eeh_ops->get_state(edev->pe, NULL);
0052     return sprintf(buf, "0x%08x 0x%08x\n",
0053                state, edev->pe->state);
0054 }
0055
0056 static ssize_t eeh_pe_state_store(struct device *dev,
0057                   struct device_attribute *attr,
0058                   const char *buf, size_t count)
0059 {
0060     struct pci_dev *pdev = to_pci_dev(dev);
0061     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0062
0063     if (!edev || !edev->pe)
0064         return -ENODEV;
0065
0066     /* Nothing to do if it's not frozen */
0067     if (!(edev->pe->state & EEH_PE_ISOLATED))
0068         return count;
0069
0070     if (eeh_unfreeze_pe(edev->pe))
0071         return -EIO;
0072     eeh_pe_state_clear(edev->pe, EEH_PE_ISOLATED, true);
0073
0074     return count;
0075 }
0076
0077 static DEVICE_ATTR_RW(eeh_pe_state);
0078
0079 #if defined(CONFIG_PCI_IOV) && defined(CONFIG_PPC_PSERIES)
0080 static ssize_t eeh_notify_resume_show(struct device *dev,
0081                       struct device_attribute *attr, char *buf)
0082 {
0083     struct pci_dev *pdev = to_pci_dev(dev);
0084     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0085     struct pci_dn *pdn = pci_get_pdn(pdev);
0086
0087     if (!edev || !edev->pe)
0088         return -ENODEV;
0089
0090     return sprintf(buf, "%d\n", pdn->last_allow_rc);
0091 }
0092
0093 static ssize_t eeh_notify_resume_store(struct device *dev,
0094                        struct device_attribute *attr,
0095                        const char *buf, size_t count)
0096 {
0097     struct pci_dev *pdev = to_pci_dev(dev);
0098     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0099
0100     if (!edev || !edev->pe || !eeh_ops->notify_resume)
0101         return -ENODEV;
0102
0103     if (eeh_ops->notify_resume(edev))
0104         return -EIO;
0105
0106     return count;
0107 }
0108 static DEVICE_ATTR_RW(eeh_notify_resume);
0109
0110 static int eeh_notify_resume_add(struct pci_dev *pdev)
0111 {
0112     struct device_node *np;
0113     int rc = 0;
0114
0115     np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
0116
0117     if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
0118         rc = device_create_file(&pdev->dev, &dev_attr_eeh_notify_resume);
0119
0120     return rc;
0121 }
0122
0123 static void eeh_notify_resume_remove(struct pci_dev *pdev)
0124 {
0125     struct device_node *np;
0126
0127     np = pci_device_to_OF_node(pdev->is_physfn ? pdev : pdev->physfn);
0128
0129     if (of_property_read_bool(np, "ibm,is-open-sriov-pf"))
0130         device_remove_file(&pdev->dev, &dev_attr_eeh_notify_resume);
0131 }
0132 #else
0133 static inline int eeh_notify_resume_add(struct pci_dev *pdev) { return 0; }
0134 static inline void eeh_notify_resume_remove(struct pci_dev *pdev) { }
0135 #endif /* CONFIG_PCI_IOV && CONFIG PPC_PSERIES*/
0136
0137 void eeh_sysfs_add_device(struct pci_dev *pdev)
0138 {
0139     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0140     int rc=0;
0141
0142     if (!eeh_enabled())
0143         return;
0144
0145     if (edev && (edev->mode & EEH_DEV_SYSFS))
0146         return;
0147
0148     rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode);
0149     rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
0150     rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_state);
0151     rc += eeh_notify_resume_add(pdev);
0152
0153     if (rc)
0154         pr_warn("EEH: Unable to create sysfs entries\n");
0155     else if (edev)
0156         edev->mode |= EEH_DEV_SYSFS;
0157 }
0158
0159 void eeh_sysfs_remove_device(struct pci_dev *pdev)
0160 {
0161     struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
0162
0163     if (!edev) {
0164         WARN_ON(eeh_enabled());
0165         return;
0166     }
0167
0168     edev->mode &= ~EEH_DEV_SYSFS;
0169
0170     /*
0171      * The parent directory might have been removed. We needn't
0172      * continue for that case.
0173      */
0174     if (!pdev->dev.kobj.sd)
0175         return;
0176
0177     device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
0178     device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
0179     device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
0180
0181     eeh_notify_resume_remove(pdev);
0182 }