src/southbridge/intel/i82801ix/smbus.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright (C) 2008-2009 coresystems GmbH
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; version 2 of
   9  * the License.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #include <console/console.h>
  18 #include <device/device.h>
  19 #include <device/path.h>
  20 #include <device/smbus.h>
  21 #include <device/pci.h>
  22 #include <device/pci_ids.h>
  23 #include <device/pci_ops.h>
  24 #include <arch/io.h>
  25 #include "smbus.h"
  26
  27 static void pch_smbus_init(device_t dev)
  28 {
  29         u16 reg16;
  30
  31         /* Enable clock gating */
  32         reg16 = pci_read_config16(dev, 0x80);
  33         reg16 &= ~((1 << 8)|(1 << 10)|(1 << 12)|(1 << 14));
  34         pci_write_config16(dev, 0x80, reg16);
  35 }
  36
  37 static int lsmbus_read_byte(device_t dev, u8 address)
  38 {
  39         u16 device;
  40         struct resource *res;
  41         struct bus *pbus;
  42
  43         device = dev->path.i2c.device;
  44         pbus = get_pbus_smbus(dev);
  45         res = find_resource(pbus->dev, 0x20);
  46
  47         return do_smbus_read_byte(res->base, device, address);
  48 }
  49
  50 static int lsmbus_write_byte(device_t dev, u8 address, u8 val)
  51 {
  52         u16 device;
  53         struct resource *res;
  54         struct bus *pbus;
  55
  56         device = dev->path.i2c.device;
  57         pbus = get_pbus_smbus(dev);
  58         res = find_resource(pbus->dev, 0x20);
  59
  60         return do_smbus_write_byte(res->base, device, address, val);
  61 }
  62
  63 static struct smbus_bus_operations lops_smbus_bus = {
  64         .read_byte      = lsmbus_read_byte,
  65         .write_byte     = lsmbus_write_byte,
  66 };
  67
  68 static void smbus_set_subsystem(device_t dev, unsigned vendor, unsigned device)
  69 {
  70         if (!vendor || !device) {
  71                 pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
  72                                 pci_read_config32(dev, PCI_VENDOR_ID));
  73         } else {
  74                 pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
  75                                 ((device & 0xffff) << 16) | (vendor & 0xffff));
  76         }
  77 }
  78
  79 static struct pci_operations smbus_pci_ops = {
  80         .set_subsystem    = smbus_set_subsystem,
  81 };
  82
  83 static void smbus_read_resources(device_t dev)
  84 {
  85         struct resource *res = new_resource(dev, PCI_BASE_ADDRESS_4);
  86         res->base = SMBUS_IO_BASE;
  87         res->size = 32;
  88         res->limit = res->base + res->size - 1;
  89         res->flags = IORESOURCE_IO | IORESOURCE_FIXED | IORESOURCE_RESERVE |
  90                      IORESOURCE_STORED | IORESOURCE_ASSIGNED;
  91
  92         /* Also add MMIO resource */
  93         res = pci_get_resource(dev, PCI_BASE_ADDRESS_0);
  94 }
  95
  96 static struct device_operations smbus_ops = {
  97         .read_resources         = smbus_read_resources,
  98         .set_resources          = pci_dev_set_resources,
  99         .enable_resources       = pci_dev_enable_resources,
 100         .scan_bus               = scan_smbus,
 101         .init                   = pch_smbus_init,
 102         .ops_smbus_bus          = &lops_smbus_bus,
 103         .ops_pci                = &smbus_pci_ops,
 104 };
 105
 106 static const unsigned short pci_device_ids[] = { 0x2930, 0 };
 107
 108 static const struct pci_driver pch_smbus __pci_driver = {
 109         .ops     = &smbus_ops,
 110         .vendor  = PCI_VENDOR_ID_INTEL,
 111         .devices = pci_device_ids,
 112 };