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
25static int 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
41static const struct ide_port_info rz1000_chipset = {
42	.name		= DRV_NAME,
43	.host_flags	= IDE_HFLAG_NO_DMA,
44};
45
46static int 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
63static void rz1000_remove(struct pci_dev *dev)
64{
65	ide_pci_remove(dev);
66	pci_disable_device(dev);
67}
68
69static 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};
74MODULE_DEVICE_TABLE(pci, rz1000_pci_tbl);
75
76static 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
83static int __init rz1000_ide_init(void)
84{
85	return ide_pci_register_driver(&rz1000_pci_driver);
86}
87
88static void __exit rz1000_ide_exit(void)
89{
90	pci_unregister_driver(&rz1000_pci_driver);
91}
92
93module_init(rz1000_ide_init);
94module_exit(rz1000_ide_exit);
95
96MODULE_AUTHOR("Andre Hedrick");
97MODULE_DESCRIPTION("PCI driver module for RZ1000 IDE");
98MODULE_LICENSE("GPL");
99
100