1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 1995-1998 Linus Torvalds & author (see below)
4 */
5
6 /*
7 * Principal Author: mlord@pobox.com (Mark Lord)
8 *
9 * See linux/MAINTAINERS for address of current maintainer.
10 *
11 * This file provides support for disabling the buggy read-ahead
12 * mode of the RZ1000 IDE chipset, commonly used on Intel motherboards.
13 *
14 * Dunno if this fixes both ports, or only the primary port (?).
15 */
16
17 #include <linux/types.h>
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/ide.h>
22 #include <linux/init.h>
23
24 #define DRV_NAME "rz1000"
25
rz1000_disable_readahead(struct pci_dev * dev)26 static int rz1000_disable_readahead(struct pci_dev *dev)
27 {
28 u16 reg;
29
30 if (!pci_read_config_word (dev, 0x40, ®) &&
31 !pci_write_config_word(dev, 0x40, reg & 0xdfff)) {
32 printk(KERN_INFO "%s: disabled chipset read-ahead "
33 "(buggy RZ1000/RZ1001)\n", pci_name(dev));
34 return 0;
35 } else {
36 printk(KERN_INFO "%s: serialized, disabled unmasking "
37 "(buggy RZ1000/RZ1001)\n", pci_name(dev));
38 return 1;
39 }
40 }
41
42 static const struct ide_port_info rz1000_chipset = {
43 .name = DRV_NAME,
44 .host_flags = IDE_HFLAG_NO_DMA,
45 };
46
rz1000_init_one(struct pci_dev * dev,const struct pci_device_id * id)47 static int rz1000_init_one(struct pci_dev *dev, const struct pci_device_id *id)
48 {
49 struct ide_port_info d = rz1000_chipset;
50 int rc;
51
52 rc = pci_enable_device(dev);
53 if (rc)
54 return rc;
55
56 if (rz1000_disable_readahead(dev)) {
57 d.host_flags |= IDE_HFLAG_SERIALIZE;
58 d.host_flags |= IDE_HFLAG_NO_UNMASK_IRQS;
59 }
60
61 return ide_pci_init_one(dev, &d, NULL);
62 }
63
rz1000_remove(struct pci_dev * dev)64 static void rz1000_remove(struct pci_dev *dev)
65 {
66 ide_pci_remove(dev);
67 pci_disable_device(dev);
68 }
69
70 static const struct pci_device_id rz1000_pci_tbl[] = {
71 { PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1000), 0 },
72 { PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1001), 0 },
73 { 0, },
74 };
75 MODULE_DEVICE_TABLE(pci, rz1000_pci_tbl);
76
77 static struct pci_driver rz1000_pci_driver = {
78 .name = "RZ1000_IDE",
79 .id_table = rz1000_pci_tbl,
80 .probe = rz1000_init_one,
81 .remove = rz1000_remove,
82 };
83
rz1000_ide_init(void)84 static int __init rz1000_ide_init(void)
85 {
86 return ide_pci_register_driver(&rz1000_pci_driver);
87 }
88
rz1000_ide_exit(void)89 static void __exit rz1000_ide_exit(void)
90 {
91 pci_unregister_driver(&rz1000_pci_driver);
92 }
93
94 module_init(rz1000_ide_init);
95 module_exit(rz1000_ide_exit);
96
97 MODULE_AUTHOR("Andre Hedrick");
98 MODULE_DESCRIPTION("PCI driver module for RZ1000 IDE");
99 MODULE_LICENSE("GPL");
100
101