drivers/ide/rz1000.c

   1 /*
   2  *  Copyright (C) 1995-1998  Linus Torvalds & author (see below)
   3  */
   4
   5 /*
   6  *  Principal Author:  mlord@pobox.com (Mark Lord)
   7  *
   8  *  See linux/MAINTAINERS for address of current maintainer.
   9  *
  10  *  This file provides support for disabling the buggy read-ahead
  11  *  mode of the RZ1000 IDE chipset, commonly used on Intel motherboards.
  12  *
  13  *  Dunno if this fixes both ports, or only the primary port (?).
  14  */
  15
  16 #include <linux/types.h>
  17 #include <linux/module.h>
  18 #include <linux/kernel.h>
  19 #include <linux/pci.h>
  20 #include <linux/ide.h>
  21 #include <linux/init.h>
  22
  23 #define DRV_NAME "rz1000"
  24
  25 static int __devinit rz1000_disable_readahead(struct pci_dev *dev)
  26 {
  27         u16 reg;
  28
  29         if (!pci_read_config_word (dev, 0x40, &reg) &&
  30             !pci_write_config_word(dev, 0x40, reg & 0xdfff)) {
  31                 printk(KERN_INFO "%s: disabled chipset read-ahead "
  32                         "(buggy RZ1000/RZ1001)\n", pci_name(dev));
  33                 return 0;
  34         } else {
  35                 printk(KERN_INFO "%s: serialized, disabled unmasking "
  36                         "(buggy RZ1000/RZ1001)\n", pci_name(dev));
  37                 return 1;
  38         }
  39 }
  40
  41 static const struct ide_port_info rz1000_chipset __devinitconst = {
  42         .name           = DRV_NAME,
  43         .host_flags     = IDE_HFLAG_NO_DMA,
  44 };
  45
  46 static int __devinit rz1000_init_one(struct pci_dev *dev, const struct pci_device_id *id)
  47 {
  48         struct ide_port_info d = rz1000_chipset;
  49         int rc;
  50
  51         rc = pci_enable_device(dev);
  52         if (rc)
  53                 return rc;
  54
  55         if (rz1000_disable_readahead(dev)) {
  56                 d.host_flags |= IDE_HFLAG_SERIALIZE;
  57                 d.host_flags |= IDE_HFLAG_NO_UNMASK_IRQS;
  58         }
  59
  60         return ide_pci_init_one(dev, &d, NULL);
  61 }
  62
  63 static void rz1000_remove(struct pci_dev *dev)
  64 {
  65         ide_pci_remove(dev);
  66         pci_disable_device(dev);
  67 }
  68
  69 static const struct pci_device_id rz1000_pci_tbl[] = {
  70         { PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1000), 0 },
  71         { PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1001), 0 },
  72         { 0, },
  73 };
  74 MODULE_DEVICE_TABLE(pci, rz1000_pci_tbl);
  75
  76 static struct pci_driver rz1000_pci_driver = {
  77         .name           = "RZ1000_IDE",
  78         .id_table       = rz1000_pci_tbl,
  79         .probe          = rz1000_init_one,
  80         .remove         = rz1000_remove,
  81 };
  82
  83 static int __init rz1000_ide_init(void)
  84 {
  85         return ide_pci_register_driver(&rz1000_pci_driver);
  86 }
  87
  88 static void __exit rz1000_ide_exit(void)
  89 {
  90         pci_unregister_driver(&rz1000_pci_driver);
  91 }
  92
  93 module_init(rz1000_ide_init);
  94 module_exit(rz1000_ide_exit);
  95
  96 MODULE_AUTHOR("Andre Hedrick");
  97 MODULE_DESCRIPTION("PCI driver module for RZ1000 IDE");
  98 MODULE_LICENSE("GPL");
  99