xref: /openbmc/linux/drivers/ata/pata_rz1000.c (revision 60772e48)
1 /*
2  *  RZ1000/1001 driver based upon
3  *
4  *  linux/drivers/ide/pci/rz1000.c	Version 0.06	January 12, 2003
5  *  Copyright (C) 1995-1998  Linus Torvalds & author (see below)
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 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pci.h>
17 #include <linux/blkdev.h>
18 #include <linux/delay.h>
19 #include <scsi/scsi_host.h>
20 #include <linux/libata.h>
21 
22 #define DRV_NAME	"pata_rz1000"
23 #define DRV_VERSION	"0.2.4"
24 
25 
26 /**
27  *	rz1000_set_mode		-	mode setting function
28  *	@link: ATA link
29  *	@unused: returned device on set_mode failure
30  *
31  *	Use a non standard set_mode function. We don't want to be tuned. We
32  *	would prefer to be BIOS generic but for the fact our hardware is
33  *	whacked out.
34  */
35 
36 static int rz1000_set_mode(struct ata_link *link, struct ata_device **unused)
37 {
38 	struct ata_device *dev;
39 
40 	ata_for_each_dev(dev, link, ENABLED) {
41 		/* We don't really care */
42 		dev->pio_mode = XFER_PIO_0;
43 		dev->xfer_mode = XFER_PIO_0;
44 		dev->xfer_shift = ATA_SHIFT_PIO;
45 		dev->flags |= ATA_DFLAG_PIO;
46 		ata_dev_info(dev, "configured for PIO\n");
47 	}
48 	return 0;
49 }
50 
51 
52 static struct scsi_host_template rz1000_sht = {
53 	ATA_PIO_SHT(DRV_NAME),
54 };
55 
56 static struct ata_port_operations rz1000_port_ops = {
57 	.inherits	= &ata_sff_port_ops,
58 	.cable_detect	= ata_cable_40wire,
59 	.set_mode	= rz1000_set_mode,
60 };
61 
62 static int rz1000_fifo_disable(struct pci_dev *pdev)
63 {
64 	u16 reg;
65 	/* Be exceptionally paranoid as we must be sure to apply the fix */
66 	if (pci_read_config_word(pdev, 0x40, &reg) != 0)
67 		return -1;
68 	reg &= 0xDFFF;
69 	if (pci_write_config_word(pdev, 0x40, reg) != 0)
70 		return -1;
71 	printk(KERN_INFO DRV_NAME ": disabled chipset readahead.\n");
72 	return 0;
73 }
74 
75 /**
76  *	rz1000_init_one - Register RZ1000 ATA PCI device with kernel services
77  *	@pdev: PCI device to register
78  *	@ent: Entry in rz1000_pci_tbl matching with @pdev
79  *
80  *	Configure an RZ1000 interface. This doesn't require much special
81  *	handling except that we *MUST* kill the chipset readahead or the
82  *	user may experience data corruption.
83  */
84 
85 static int rz1000_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
86 {
87 	static const struct ata_port_info info = {
88 		.flags = ATA_FLAG_SLAVE_POSS,
89 		.pio_mask = ATA_PIO4,
90 		.port_ops = &rz1000_port_ops
91 	};
92 	const struct ata_port_info *ppi[] = { &info, NULL };
93 
94 	ata_print_version_once(&pdev->dev, DRV_VERSION);
95 
96 	if (rz1000_fifo_disable(pdev) == 0)
97 		return ata_pci_sff_init_one(pdev, ppi, &rz1000_sht, NULL, 0);
98 
99 	printk(KERN_ERR DRV_NAME ": failed to disable read-ahead on chipset..\n");
100 	/* Not safe to use so skip */
101 	return -ENODEV;
102 }
103 
104 #ifdef CONFIG_PM_SLEEP
105 static int rz1000_reinit_one(struct pci_dev *pdev)
106 {
107 	struct ata_host *host = pci_get_drvdata(pdev);
108 	int rc;
109 
110 	rc = ata_pci_device_do_resume(pdev);
111 	if (rc)
112 		return rc;
113 
114 	/* If this fails on resume (which is a "can't happen" case), we
115 	   must stop as any progress risks data loss */
116 	if (rz1000_fifo_disable(pdev))
117 		panic("rz1000 fifo");
118 
119 	ata_host_resume(host);
120 	return 0;
121 }
122 #endif
123 
124 static const struct pci_device_id pata_rz1000[] = {
125 	{ PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1000), },
126 	{ PCI_VDEVICE(PCTECH, PCI_DEVICE_ID_PCTECH_RZ1001), },
127 
128 	{ },
129 };
130 
131 static struct pci_driver rz1000_pci_driver = {
132 	.name 		= DRV_NAME,
133 	.id_table	= pata_rz1000,
134 	.probe 		= rz1000_init_one,
135 	.remove		= ata_pci_remove_one,
136 #ifdef CONFIG_PM_SLEEP
137 	.suspend	= ata_pci_device_suspend,
138 	.resume		= rz1000_reinit_one,
139 #endif
140 };
141 
142 module_pci_driver(rz1000_pci_driver);
143 
144 MODULE_AUTHOR("Alan Cox");
145 MODULE_DESCRIPTION("low-level driver for RZ1000 PCI ATA");
146 MODULE_LICENSE("GPL");
147 MODULE_DEVICE_TABLE(pci, pata_rz1000);
148 MODULE_VERSION(DRV_VERSION);
149