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1// SPDX-License-Identifier: GPL-2.02/*3 * PCI Backend - Handle special overlays for broken devices.4 *5 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>6 * Author: Chris Bookholt <hap10@epoch.ncsc.mil>7 */8 9#define dev_fmt(fmt) DRV_NAME ": " fmt10 11#include <linux/kernel.h>12#include <linux/pci.h>13#include "pciback.h"14#include "conf_space.h"15#include "conf_space_quirks.h"16 17LIST_HEAD(xen_pcibk_quirks);18static inline const struct pci_device_id *19match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)20{21 if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&22 (id->device == PCI_ANY_ID || id->device == dev->device) &&23 (id->subvendor == PCI_ANY_ID ||24 id->subvendor == dev->subsystem_vendor) &&25 (id->subdevice == PCI_ANY_ID ||26 id->subdevice == dev->subsystem_device) &&27 !((id->class ^ dev->class) & id->class_mask))28 return id;29 return NULL;30}31 32static struct xen_pcibk_config_quirk *xen_pcibk_find_quirk(struct pci_dev *dev)33{34 struct xen_pcibk_config_quirk *tmp_quirk;35 36 list_for_each_entry(tmp_quirk, &xen_pcibk_quirks, quirks_list)37 if (match_one_device(&tmp_quirk->devid, dev) != NULL)38 goto out;39 tmp_quirk = NULL;40 dev_printk(KERN_DEBUG, &dev->dev,41 "quirk didn't match any device known\n");42out:43 return tmp_quirk;44}45 46static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)47{48 list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);49}50 51int xen_pcibk_field_is_dup(struct pci_dev *dev, unsigned int reg)52{53 int ret = 0;54 struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);55 struct config_field_entry *cfg_entry;56 57 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {58 if (OFFSET(cfg_entry) == reg) {59 ret = 1;60 break;61 }62 }63 return ret;64}65 66int xen_pcibk_config_quirks_add_field(struct pci_dev *dev, struct config_field67 *field)68{69 int err = 0;70 71 switch (field->size) {72 case 1:73 field->u.b.read = xen_pcibk_read_config_byte;74 field->u.b.write = xen_pcibk_write_config_byte;75 break;76 case 2:77 field->u.w.read = xen_pcibk_read_config_word;78 field->u.w.write = xen_pcibk_write_config_word;79 break;80 case 4:81 field->u.dw.read = xen_pcibk_read_config_dword;82 field->u.dw.write = xen_pcibk_write_config_dword;83 break;84 default:85 err = -EINVAL;86 goto out;87 }88 89 xen_pcibk_config_add_field(dev, field);90 91out:92 return err;93}94 95int xen_pcibk_config_quirks_init(struct pci_dev *dev)96{97 struct xen_pcibk_config_quirk *quirk;98 int ret = 0;99 100 quirk = kzalloc(sizeof(*quirk), GFP_KERNEL);101 if (!quirk) {102 ret = -ENOMEM;103 goto out;104 }105 106 quirk->devid.vendor = dev->vendor;107 quirk->devid.device = dev->device;108 quirk->devid.subvendor = dev->subsystem_vendor;109 quirk->devid.subdevice = dev->subsystem_device;110 quirk->devid.class = 0;111 quirk->devid.class_mask = 0;112 quirk->devid.driver_data = 0UL;113 114 quirk->pdev = dev;115 116 register_quirk(quirk);117out:118 return ret;119}120 121void xen_pcibk_config_field_free(struct config_field *field)122{123 kfree(field);124}125 126int xen_pcibk_config_quirk_release(struct pci_dev *dev)127{128 struct xen_pcibk_config_quirk *quirk;129 int ret = 0;130 131 quirk = xen_pcibk_find_quirk(dev);132 if (!quirk) {133 ret = -ENXIO;134 goto out;135 }136 137 list_del(&quirk->quirks_list);138 kfree(quirk);139 140out:141 return ret;142}143