arch/powerpc/kernel/eeh_sysfs.c

   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 }