1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  RZ1000/1001 driver based upon
4 *
5 *  linux/drivers/ide/pci/rz1000.c	Version 0.06	January 12, 2003
6 *  Copyright (C) 1995-1998  Linus Torvalds & author (see below)
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
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/pci.h>
18#include <linux/blkdev.h>
19#include <linux/delay.h>
20#include <scsi/scsi_host.h>
21#include <linux/libata.h>
22
23#define DRV_NAME	"pata_rz1000"
24#define DRV_VERSION	"0.2.4"
25
26
27/**
28 *	rz1000_set_mode		-	mode setting function
29 *	@link: ATA link
30 *	@unused: returned device on set_mode failure
31 *
32 *	Use a non standard set_mode function. We don't want to be tuned. We
33 *	would prefer to be BIOS generic but for the fact our hardware is
34 *	whacked out.
35 */
36
37static int rz1000_set_mode(struct ata_link *link, struct ata_device **unused)
38{
39	struct ata_device *dev;
40
41	ata_for_each_dev(dev, link, ENABLED) {
42		/* We don't really care */
43		dev->pio_mode = XFER_PIO_0;
44		dev->xfer_mode = XFER_PIO_0;
45		dev->xfer_shift = ATA_SHIFT_PIO;
46		dev->flags |= ATA_DFLAG_PIO;
47		ata_dev_info(dev, "configured for PIO\n");
48	}
49	return 0;
50}
51
52
53static const struct scsi_host_template rz1000_sht = {
54	ATA_PIO_SHT(DRV_NAME),
55};
56
57static struct ata_port_operations rz1000_port_ops = {
58	.inherits	= &ata_sff_port_ops,
59	.cable_detect	= ata_cable_40wire,
60	.set_mode	= rz1000_set_mode,
61};
62
63static int rz1000_fifo_disable(struct pci_dev *pdev)
64{
65	u16 reg;
66	/* Be exceptionally paranoid as we must be sure to apply the fix */
67	if (pci_read_config_word(pdev, 0x40, &reg) != 0)
68		return -1;
69	reg &= 0xDFFF;
70	if (pci_write_config_word(pdev, 0x40, reg) != 0)
71		return -1;
72	dev_info(&pdev->dev, "disabled chipset readahead.\n");
73	return 0;
74}
75
76/**
77 *	rz1000_init_one - Register RZ1000 ATA PCI device with kernel services
78 *	@pdev: PCI device to register
79 *	@ent: Entry in rz1000_pci_tbl matching with @pdev
80 *
81 *	Configure an RZ1000 interface. This doesn't require much special
82 *	handling except that we *MUST* kill the chipset readahead or the
83 *	user may experience data corruption.
84 */
85
86static int rz1000_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
87{
88	static const struct ata_port_info info = {
89		.flags = ATA_FLAG_SLAVE_POSS,
90		.pio_mask = ATA_PIO4,
91		.port_ops = &rz1000_port_ops
92	};
93	const struct ata_port_info *ppi[] = { &info, NULL };
94
95	ata_print_version_once(&pdev->dev, DRV_VERSION);
96
97	if (rz1000_fifo_disable(pdev) == 0)
98		return ata_pci_sff_init_one(pdev, ppi, &rz1000_sht, NULL, 0);
99
100	dev_err(&pdev->dev, "failed to disable read-ahead on chipset.\n");
101	/* Not safe to use so skip */
102	return -ENODEV;
103}
104
105#ifdef CONFIG_PM_SLEEP
106static int rz1000_reinit_one(struct pci_dev *pdev)
107{
108	struct ata_host *host = pci_get_drvdata(pdev);
109	int rc;
110
111	rc = ata_pci_device_do_resume(pdev);
112	if (rc)
113		return rc;
114
115	/* If this fails on resume (which is a "can't happen" case), we
116	   must stop as any progress risks data loss */
117	if (rz1000_fifo_disable(pdev))
118		panic("rz1000 fifo");
119
120	ata_host_resume(host);
121	return 0;
122}
123#endif
124
125static const struct pci_device_id pata_rz1000[] = {
126	{ PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1000), },
127	{ PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1001), },
128
129	{ },
130};
131
132static struct pci_driver rz1000_pci_driver = {
133	.name 		= DRV_NAME,
134	.id_table	= pata_rz1000,
135	.probe 		= rz1000_init_one,
136	.remove		= ata_pci_remove_one,
137#ifdef CONFIG_PM_SLEEP
138	.suspend	= ata_pci_device_suspend,
139	.resume		= rz1000_reinit_one,
140#endif
141};
142
143module_pci_driver(rz1000_pci_driver);
144
145MODULE_AUTHOR("Alan Cox");
146MODULE_DESCRIPTION("low-level driver for RZ1000 PCI ATA");
147MODULE_LICENSE("GPL");
148MODULE_DEVICE_TABLE(pci, pata_rz1000);
149MODULE_VERSION(DRV_VERSION);
150