payloads/libpayload/drivers/pci_ops.c

   1 /*
   2  *
   3  * Copyright (C) 2008 Advanced Micro Devices, Inc.
   4  * Copyright (C) 2008 coresystems GmbH
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <libpayload.h>
  31 #include <pci.h>
  32
  33 static int find_on_bus(int bus, unsigned short vid, unsigned short did,
  34                        pcidev_t * dev)
  35 {
  36         int devfn;
  37         u32 val;
  38         unsigned char hdr;
  39
  40         for (devfn = 0; devfn < 0x100; devfn++) {
  41                 int func = devfn & 0x7;
  42                 int slot = (devfn >> 3) & 0x1f;
  43
  44                 val = pci_read_config32(PCI_DEV(bus, slot, func),
  45                                         REG_VENDOR_ID);
  46
  47                 if (val == 0xffffffff || val == 0x00000000 ||
  48                     val == 0x0000ffff || val == 0xffff0000)
  49                         continue;
  50
  51                 if (val == ((did << 16) | vid)) {
  52                         *dev = PCI_DEV(bus, slot, func);
  53                         return 1;
  54                 }
  55
  56                 hdr = pci_read_config8(PCI_DEV(bus, slot, func),
  57                                        REG_HEADER_TYPE);
  58                 hdr &= 0x7F;
  59
  60                 if (hdr == HEADER_TYPE_BRIDGE || hdr == HEADER_TYPE_CARDBUS) {
  61                         unsigned int busses;
  62                         busses = pci_read_config32(PCI_DEV(bus, slot, func),
  63                                                    REG_PRIMARY_BUS);
  64                         busses = (busses >> 8) & 0xFF;
  65
  66                         /* Avoid recursion if the new bus is the same as
  67                          * the old bus (insert lame The Who joke here) */
  68
  69                         if ((busses != bus) &&
  70                             find_on_bus(busses, vid, did, dev))
  71                                 return 1;
  72                 }
  73         }
  74
  75         return 0;
  76 }
  77
  78 int pci_find_device(u16 vid, u16 did, pcidev_t * dev)
  79 {
  80         return find_on_bus(0, vid, did, dev);
  81 }
  82
  83 u32 pci_read_resource(pcidev_t dev, int bar)
  84 {
  85         return pci_read_config32(dev, 0x10 + (bar * 4));
  86 }
  87
  88 void pci_set_bus_master(pcidev_t dev)
  89 {
  90         u16 val = pci_read_config16(dev, REG_COMMAND);
  91         val |= REG_COMMAND_BM;
  92         pci_write_config16(dev, REG_COMMAND, val);
  93 }