drivers/pci/hotplug/cpci_hotplug_pci.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * CompactPCI Hot Plug Driver PCI functions
   4  *
   5  * Copyright (C) 2002,2005 by SOMA Networks, Inc.
   6  *
   7  * All rights reserved.
   8  *
   9  * Send feedback to <[email protected]>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/pci.h>
  15 #include <linux/pci_hotplug.h>
  16 #include <linux/proc_fs.h>
  17 #include "../pci.h"
  18 #include "cpci_hotplug.h"
  19
  20 #define MY_NAME "cpci_hotplug"
  21
  22 #define dbg(format, arg...)                                     \
  23         do {                                                    \
  24                 if (cpci_debug)                                 \
  25                         printk(KERN_DEBUG "%s: " format "\n",   \
  26                                 MY_NAME, ## arg);               \
  27         } while (0)
  28 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
  29 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
  30 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
  31
  32
  33 u8 cpci_get_attention_status(struct slot *slot)
  34 {
  35         int hs_cap;
  36         u16 hs_csr;
  37
  38         hs_cap = pci_bus_find_capability(slot->bus,
  39                                          slot->devfn,
  40                                          PCI_CAP_ID_CHSWP);
  41         if (!hs_cap)
  42                 return 0;
  43
  44         if (pci_bus_read_config_word(slot->bus,
  45                                      slot->devfn,
  46                                      hs_cap + 2,
  47                                      &hs_csr))
  48                 return 0;
  49
  50         return hs_csr & 0x0008 ? 1 : 0;
  51 }
  52
  53 int cpci_set_attention_status(struct slot *slot, int status)
  54 {
  55         int hs_cap;
  56         u16 hs_csr;
  57
  58         hs_cap = pci_bus_find_capability(slot->bus,
  59                                          slot->devfn,
  60                                          PCI_CAP_ID_CHSWP);
  61         if (!hs_cap)
  62                 return 0;
  63         if (pci_bus_read_config_word(slot->bus,
  64                                      slot->devfn,
  65                                      hs_cap + 2,
  66                                      &hs_csr))
  67                 return 0;
  68         if (status)
  69                 hs_csr |= HS_CSR_LOO;
  70         else
  71                 hs_csr &= ~HS_CSR_LOO;
  72         if (pci_bus_write_config_word(slot->bus,
  73                                       slot->devfn,
  74                                       hs_cap + 2,
  75                                       hs_csr))
  76                 return 0;
  77         return 1;
  78 }
  79
  80 u16 cpci_get_hs_csr(struct slot *slot)
  81 {
  82         int hs_cap;
  83         u16 hs_csr;
  84
  85         hs_cap = pci_bus_find_capability(slot->bus,
  86                                          slot->devfn,
  87                                          PCI_CAP_ID_CHSWP);
  88         if (!hs_cap)
  89                 return 0xFFFF;
  90         if (pci_bus_read_config_word(slot->bus,
  91                                      slot->devfn,
  92                                      hs_cap + 2,
  93                                      &hs_csr))
  94                 return 0xFFFF;
  95         return hs_csr;
  96 }
  97
  98 int cpci_check_and_clear_ins(struct slot *slot)
  99 {
 100         int hs_cap;
 101         u16 hs_csr;
 102         int ins = 0;
 103
 104         hs_cap = pci_bus_find_capability(slot->bus,
 105                                          slot->devfn,
 106                                          PCI_CAP_ID_CHSWP);
 107         if (!hs_cap)
 108                 return 0;
 109         if (pci_bus_read_config_word(slot->bus,
 110                                      slot->devfn,
 111                                      hs_cap + 2,
 112                                      &hs_csr))
 113                 return 0;
 114         if (hs_csr & HS_CSR_INS) {
 115                 /* Clear INS (by setting it) */
 116                 if (pci_bus_write_config_word(slot->bus,
 117                                               slot->devfn,
 118                                               hs_cap + 2,
 119                                               hs_csr))
 120                         ins = 0;
 121                 else
 122                         ins = 1;
 123         }
 124         return ins;
 125 }
 126
 127 int cpci_check_ext(struct slot *slot)
 128 {
 129         int hs_cap;
 130         u16 hs_csr;
 131         int ext = 0;
 132
 133         hs_cap = pci_bus_find_capability(slot->bus,
 134                                          slot->devfn,
 135                                          PCI_CAP_ID_CHSWP);
 136         if (!hs_cap)
 137                 return 0;
 138         if (pci_bus_read_config_word(slot->bus,
 139                                      slot->devfn,
 140                                      hs_cap + 2,
 141                                      &hs_csr))
 142                 return 0;
 143         if (hs_csr & HS_CSR_EXT)
 144                 ext = 1;
 145         return ext;
 146 }
 147
 148 int cpci_clear_ext(struct slot *slot)
 149 {
 150         int hs_cap;
 151         u16 hs_csr;
 152
 153         hs_cap = pci_bus_find_capability(slot->bus,
 154                                          slot->devfn,
 155                                          PCI_CAP_ID_CHSWP);
 156         if (!hs_cap)
 157                 return -ENODEV;
 158         if (pci_bus_read_config_word(slot->bus,
 159                                      slot->devfn,
 160                                      hs_cap + 2,
 161                                      &hs_csr))
 162                 return -ENODEV;
 163         if (hs_csr & HS_CSR_EXT) {
 164                 /* Clear EXT (by setting it) */
 165                 if (pci_bus_write_config_word(slot->bus,
 166                                               slot->devfn,
 167                                               hs_cap + 2,
 168                                               hs_csr))
 169                         return -ENODEV;
 170         }
 171         return 0;
 172 }
 173
 174 int cpci_led_on(struct slot *slot)
 175 {
 176         int hs_cap;
 177         u16 hs_csr;
 178
 179         hs_cap = pci_bus_find_capability(slot->bus,
 180                                          slot->devfn,
 181                                          PCI_CAP_ID_CHSWP);
 182         if (!hs_cap)
 183                 return -ENODEV;
 184         if (pci_bus_read_config_word(slot->bus,
 185                                      slot->devfn,
 186                                      hs_cap + 2,
 187                                      &hs_csr))
 188                 return -ENODEV;
 189         if ((hs_csr & HS_CSR_LOO) != HS_CSR_LOO) {
 190                 hs_csr |= HS_CSR_LOO;
 191                 if (pci_bus_write_config_word(slot->bus,
 192                                               slot->devfn,
 193                                               hs_cap + 2,
 194                                               hs_csr)) {
 195                         err("Could not set LOO for slot %s", slot_name(slot));
 196                         return -ENODEV;
 197                 }
 198         }
 199         return 0;
 200 }
 201
 202 int cpci_led_off(struct slot *slot)
 203 {
 204         int hs_cap;
 205         u16 hs_csr;
 206
 207         hs_cap = pci_bus_find_capability(slot->bus,
 208                                          slot->devfn,
 209                                          PCI_CAP_ID_CHSWP);
 210         if (!hs_cap)
 211                 return -ENODEV;
 212         if (pci_bus_read_config_word(slot->bus,
 213                                      slot->devfn,
 214                                      hs_cap + 2,
 215                                      &hs_csr))
 216                 return -ENODEV;
 217         if (hs_csr & HS_CSR_LOO) {
 218                 hs_csr &= ~HS_CSR_LOO;
 219                 if (pci_bus_write_config_word(slot->bus,
 220                                               slot->devfn,
 221                                               hs_cap + 2,
 222                                               hs_csr)) {
 223                         err("Could not clear LOO for slot %s", slot_name(slot));
 224                         return -ENODEV;
 225                 }
 226         }
 227         return 0;
 228 }
 229
 230
 231 /*
 232  * Device configuration functions
 233  */
 234
 235 int cpci_configure_slot(struct slot *slot)
 236 {
 237         struct pci_dev *dev;
 238         struct pci_bus *parent;
 239         int ret = 0;
 240
 241         dbg("%s - enter", __func__);
 242
 243         pci_lock_rescan_remove();
 244
 245         if (slot->dev == NULL) {
 246                 dbg("pci_dev null, finding %02x:%02x:%x",
 247                     slot->bus->number, PCI_SLOT(slot->devfn), PCI_FUNC(slot->devfn));
 248                 slot->dev = pci_get_slot(slot->bus, slot->devfn);
 249         }
 250
 251         /* Still NULL? Well then scan for it! */
 252         if (slot->dev == NULL) {
 253                 int n;
 254                 dbg("pci_dev still null");
 255
 256                 /*
 257                  * This will generate pci_dev structures for all functions, but
 258                  * we will only call this case when lookup fails.
 259                  */
 260                 n = pci_scan_slot(slot->bus, slot->devfn);
 261                 dbg("%s: pci_scan_slot returned %d", __func__, n);
 262                 slot->dev = pci_get_slot(slot->bus, slot->devfn);
 263                 if (slot->dev == NULL) {
 264                         err("Could not find PCI device for slot %02x", slot->number);
 265                         ret = -ENODEV;
 266                         goto out;
 267                 }
 268         }
 269         parent = slot->dev->bus;
 270
 271         for_each_pci_bridge(dev, parent) {
 272                 if (PCI_SLOT(dev->devfn) == PCI_SLOT(slot->devfn))
 273                         pci_hp_add_bridge(dev);
 274         }
 275
 276         pci_assign_unassigned_bridge_resources(parent->self);
 277
 278         pci_bus_add_devices(parent);
 279
 280  out:
 281         pci_unlock_rescan_remove();
 282         dbg("%s - exit", __func__);
 283         return ret;
 284 }
 285
 286 int cpci_unconfigure_slot(struct slot *slot)
 287 {
 288         struct pci_dev *dev, *temp;
 289
 290         dbg("%s - enter", __func__);
 291         if (!slot->dev) {
 292                 err("No device for slot %02x\n", slot->number);
 293                 return -ENODEV;
 294         }
 295
 296         pci_lock_rescan_remove();
 297
 298         list_for_each_entry_safe(dev, temp, &slot->bus->devices, bus_list) {
 299                 if (PCI_SLOT(dev->devfn) != PCI_SLOT(slot->devfn))
 300                         continue;
 301                 pci_dev_get(dev);
 302                 pci_stop_and_remove_bus_device(dev);
 303                 pci_dev_put(dev);
 304         }
 305         pci_dev_put(slot->dev);
 306         slot->dev = NULL;
 307
 308         pci_unlock_rescan_remove();
 309
 310         dbg("%s - exit", __func__);
 311         return 0;
 312 }