arch/mips/pci/pci-virtio-guest.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2013 Cavium, Inc.
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/pci.h>
  13
  14 #include <uapi/asm/bitfield.h>
  15 #include <asm/byteorder.h>
  16 #include <asm/io.h>
  17
  18 #define PCI_CONFIG_ADDRESS      0xcf8
  19 #define PCI_CONFIG_DATA         0xcfc
  20
  21 union pci_config_address {
  22         struct {
  23                 __BITFIELD_FIELD(unsigned enable_bit      : 1,  /* 31       */
  24                 __BITFIELD_FIELD(unsigned reserved        : 7,  /* 30 .. 24 */
  25                 __BITFIELD_FIELD(unsigned bus_number      : 8,  /* 23 .. 16 */
  26                 __BITFIELD_FIELD(unsigned devfn_number    : 8,  /* 15 .. 8  */
  27                 __BITFIELD_FIELD(unsigned register_number : 8,  /* 7  .. 0  */
  28                 )))));
  29         };
  30         u32 w;
  31 };
  32
  33 int pcibios_plat_dev_init(struct pci_dev *dev)
  34 {
  35         return 0;
  36 }
  37
  38 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
  39 {
  40         return ((pin + slot) % 4)+ MIPS_IRQ_PCIA;
  41 }
  42
  43 static void pci_virtio_guest_write_config_addr(struct pci_bus *bus,
  44                                         unsigned int devfn, int reg)
  45 {
  46         union pci_config_address pca = { .w = 0 };
  47
  48         pca.register_number = reg;
  49         pca.devfn_number = devfn;
  50         pca.bus_number = bus->number;
  51         pca.enable_bit = 1;
  52
  53         outl(pca.w, PCI_CONFIG_ADDRESS);
  54 }
  55
  56 static int pci_virtio_guest_write_config(struct pci_bus *bus,
  57                 unsigned int devfn, int reg, int size, u32 val)
  58 {
  59         pci_virtio_guest_write_config_addr(bus, devfn, reg);
  60
  61         switch (size) {
  62         case 1:
  63                 outb(val, PCI_CONFIG_DATA + (reg & 3));
  64                 break;
  65         case 2:
  66                 outw(val, PCI_CONFIG_DATA + (reg & 2));
  67                 break;
  68         case 4:
  69                 outl(val, PCI_CONFIG_DATA);
  70                 break;
  71         }
  72
  73         return PCIBIOS_SUCCESSFUL;
  74 }
  75
  76 static int pci_virtio_guest_read_config(struct pci_bus *bus, unsigned int devfn,
  77                                         int reg, int size, u32 *val)
  78 {
  79         pci_virtio_guest_write_config_addr(bus, devfn, reg);
  80
  81         switch (size) {
  82         case 1:
  83                 *val = inb(PCI_CONFIG_DATA + (reg & 3));
  84                 break;
  85         case 2:
  86                 *val = inw(PCI_CONFIG_DATA + (reg & 2));
  87                 break;
  88         case 4:
  89                 *val = inl(PCI_CONFIG_DATA);
  90                 break;
  91         }
  92         return PCIBIOS_SUCCESSFUL;
  93 }
  94
  95 static struct pci_ops pci_virtio_guest_ops = {
  96         .read  = pci_virtio_guest_read_config,
  97         .write = pci_virtio_guest_write_config,
  98 };
  99
 100 static struct resource pci_virtio_guest_mem_resource = {
 101         .name = "Virtio MEM",
 102         .flags = IORESOURCE_MEM,
 103         .start  = 0x10000000,
 104         .end    = 0x1dffffff
 105 };
 106
 107 static struct resource pci_virtio_guest_io_resource = {
 108         .name = "Virtio IO",
 109         .flags = IORESOURCE_IO,
 110         .start  = 0,
 111         .end    = 0xffff
 112 };
 113
 114 static struct pci_controller pci_virtio_guest_controller = {
 115         .pci_ops = &pci_virtio_guest_ops,
 116         .mem_resource = &pci_virtio_guest_mem_resource,
 117         .io_resource = &pci_virtio_guest_io_resource,
 118 };
 119
 120 static int __init pci_virtio_guest_setup(void)
 121 {
 122         pr_err("pci_virtio_guest_setup\n");
 123
 124         /* Virtio comes pre-assigned */
 125         pci_set_flags(PCI_PROBE_ONLY);
 126
 127         pci_virtio_guest_controller.io_map_base = mips_io_port_base;
 128         register_pci_controller(&pci_virtio_guest_controller);
 129         return 0;
 130 }
 131 arch_initcall(pci_virtio_guest_setup);