src/device/pci_ops.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright (C) 2004 Linux Networx
   5  * (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
   6  * Copyright (C) 2009 coresystems GmbH
   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; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <console/console.h>
  19 #include <device/pci.h>
  20 #include <device/pci_ops.h>
  21
  22 static const struct pci_bus_operations *pci_bus_ops(struct bus *bus, struct device *dev)
  23 {
  24         const struct pci_bus_operations *bops;
  25         bops = NULL;
  26         if (bus && bus->dev && bus->dev->ops && bus->dev->ops->ops_pci_bus) {
  27                 bops = bus->dev->ops->ops_pci_bus(dev);
  28         }
  29         if (!bops)
  30                 bops = pci_bus_default_ops(dev);
  31         return bops;
  32 }
  33
  34 /*
  35  * The only consumer of the return value of get_pbus() is pci_bus_ops().
  36  * pci_bus_ops() can handle being passed NULL and auto-picks working ops.
  37  */
  38 static struct bus *get_pbus(struct device *dev)
  39 {
  40         struct bus *pbus = NULL;
  41
  42         if (!dev)
  43                 die("get_pbus: dev is NULL!\n");
  44         else
  45                 pbus = dev->bus;
  46
  47         while (pbus && pbus->dev && !pci_bus_ops(pbus, dev)) {
  48                 if (pbus == pbus->dev->bus) {
  49                         printk(BIOS_ALERT, "%s in endless loop looking for a "
  50                                "parent bus with pci_bus_ops for %s, breaking "
  51                                "out.\n", __func__, dev_path(dev));
  52                         break;
  53                 }
  54                 pbus = pbus->dev->bus;
  55         }
  56
  57         if (!pbus || !pbus->dev || !pbus->dev->ops
  58             || !pbus->dev->ops->ops_pci_bus) {
  59                 /* This can happen before the device tree is fully set up. */
  60
  61                 // printk(BIOS_EMERG, "%s: Cannot find PCI bus operations.\n",
  62                 // dev_path(dev));
  63
  64                 pbus = NULL;
  65         }
  66
  67         return pbus;
  68 }
  69
  70 u8 pci_read_config8(struct device *dev, unsigned int where)
  71 {
  72         struct bus *pbus = get_pbus(dev);
  73         return pci_bus_ops(pbus, dev)->read8(pbus, dev->bus->secondary,
  74                                         dev->path.pci.devfn, where);
  75 }
  76
  77 u16 pci_read_config16(struct device *dev, unsigned int where)
  78 {
  79         struct bus *pbus = get_pbus(dev);
  80         return pci_bus_ops(pbus, dev)->read16(pbus, dev->bus->secondary,
  81                                          dev->path.pci.devfn, where);
  82 }
  83
  84 u32 pci_read_config32(struct device *dev, unsigned int where)
  85 {
  86         struct bus *pbus = get_pbus(dev);
  87         return pci_bus_ops(pbus, dev)->read32(pbus, dev->bus->secondary,
  88                                          dev->path.pci.devfn, where);
  89 }
  90
  91 void pci_write_config8(struct device *dev, unsigned int where, u8 val)
  92 {
  93         struct bus *pbus = get_pbus(dev);
  94         pci_bus_ops(pbus, dev)->write8(pbus, dev->bus->secondary,
  95                                   dev->path.pci.devfn, where, val);
  96 }
  97
  98 void pci_write_config16(struct device *dev, unsigned int where, u16 val)
  99 {
 100         struct bus *pbus = get_pbus(dev);
 101         pci_bus_ops(pbus, dev)->write16(pbus, dev->bus->secondary,
 102                                    dev->path.pci.devfn, where, val);
 103 }
 104
 105 void pci_write_config32(struct device *dev, unsigned int where, u32 val)
 106 {
 107         struct bus *pbus = get_pbus(dev);
 108         pci_bus_ops(pbus, dev)->write32(pbus, dev->bus->secondary,
 109                                    dev->path.pci.devfn, where, val);
 110 }