xref: /openbmc/linux/drivers/ata/pata_opti.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * pata_opti.c 	- ATI PATA for new ATA layer
4  *			  (C) 2005 Red Hat Inc
5  *
6  * Based on
7  *  linux/drivers/ide/pci/opti621.c		Version 0.7	Sept 10, 2002
8  *
9  *  Copyright (C) 1996-1998  Linus Torvalds & authors (see below)
10  *
11  * Authors:
12  * Jaromir Koutek <miri@punknet.cz>,
13  * Jan Harkes <jaharkes@cwi.nl>,
14  * Mark Lord <mlord@pobox.com>
15  * Some parts of code are from ali14xx.c and from rz1000.c.
16  *
17  * Also consulted the FreeBSD prototype driver by Kevin Day to try
18  * and resolve some confusions. Further documentation can be found in
19  * Ralf Brown's interrupt list
20  *
21  * If you have other variants of the Opti range (Viper/Vendetta) please
22  * try this driver with those PCI idents and report back. For the later
23  * chips see the pata_optidma driver
24  *
25  */
26 
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/pci.h>
30 #include <linux/blkdev.h>
31 #include <linux/delay.h>
32 #include <scsi/scsi_host.h>
33 #include <linux/libata.h>
34 
35 #define DRV_NAME "pata_opti"
36 #define DRV_VERSION "0.2.9"
37 
38 enum {
39 	READ_REG	= 0,	/* index of Read cycle timing register */
40 	WRITE_REG 	= 1,	/* index of Write cycle timing register */
41 	CNTRL_REG 	= 3,	/* index of Control register */
42 	STRAP_REG 	= 5,	/* index of Strap register */
43 	MISC_REG 	= 6	/* index of Miscellaneous register */
44 };
45 
46 /**
47  *	opti_pre_reset		-	probe begin
48  *	@link: ATA link
49  *	@deadline: deadline jiffies for the operation
50  *
51  *	Set up cable type and use generic probe init
52  */
53 
54 static int opti_pre_reset(struct ata_link *link, unsigned long deadline)
55 {
56 	struct ata_port *ap = link->ap;
57 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
58 	static const struct pci_bits opti_enable_bits[] = {
59 		{ 0x45, 1, 0x80, 0x00 },
60 		{ 0x40, 1, 0x08, 0x00 }
61 	};
62 
63 	if (!pci_test_config_bits(pdev, &opti_enable_bits[ap->port_no]))
64 		return -ENOENT;
65 
66 	return ata_sff_prereset(link, deadline);
67 }
68 
69 /**
70  *	opti_write_reg		-	control register setup
71  *	@ap: ATA port
72  *	@value: value
73  *	@reg: control register number
74  *
75  *	The Opti uses magic 'trapdoor' register accesses to do configuration
76  *	rather than using PCI space as other controllers do. The double inw
77  *	on the error register activates configuration mode. We can then write
78  *	the control register
79  */
80 
81 static void opti_write_reg(struct ata_port *ap, u8 val, int reg)
82 {
83 	void __iomem *regio = ap->ioaddr.cmd_addr;
84 
85 	/* These 3 unlock the control register access */
86 	ioread16(regio + 1);
87 	ioread16(regio + 1);
88 	iowrite8(3, regio + 2);
89 
90 	/* Do the I/O */
91 	iowrite8(val, regio + reg);
92 
93 	/* Relock */
94 	iowrite8(0x83, regio + 2);
95 }
96 
97 /**
98  *	opti_set_piomode	-	set initial PIO mode data
99  *	@ap: ATA interface
100  *	@adev: ATA device
101  *
102  *	Called to do the PIO mode setup. Timing numbers are taken from
103  *	the FreeBSD driver then pre computed to keep the code clean. There
104  *	are two tables depending on the hardware clock speed.
105  */
106 
107 static void opti_set_piomode(struct ata_port *ap, struct ata_device *adev)
108 {
109 	struct ata_device *pair = ata_dev_pair(adev);
110 	int clock;
111 	int pio = adev->pio_mode - XFER_PIO_0;
112 	void __iomem *regio = ap->ioaddr.cmd_addr;
113 	u8 addr;
114 
115 	/* Address table precomputed with prefetch off and a DCLK of 2 */
116 	static const u8 addr_timing[2][5] = {
117 		{ 0x30, 0x20, 0x20, 0x10, 0x10 },
118 		{ 0x20, 0x20, 0x10, 0x10, 0x10 }
119 	};
120 	static const u8 data_rec_timing[2][5] = {
121 		{ 0x6B, 0x56, 0x42, 0x32, 0x31 },
122 		{ 0x58, 0x44, 0x32, 0x22, 0x21 }
123 	};
124 
125 	iowrite8(0xff, regio + 5);
126 	clock = ioread16(regio + 5) & 1;
127 
128 	/*
129  	 *	As with many controllers the address setup time is shared
130  	 *	and must suit both devices if present.
131 	 */
132 
133 	addr = addr_timing[clock][pio];
134 	if (pair) {
135 		/* Hardware constraint */
136 		u8 pair_addr = addr_timing[clock][pair->pio_mode - XFER_PIO_0];
137 		if (pair_addr > addr)
138 			addr = pair_addr;
139 	}
140 
141 	/* Commence primary programming sequence */
142 	opti_write_reg(ap, adev->devno, MISC_REG);
143 	opti_write_reg(ap, data_rec_timing[clock][pio], READ_REG);
144 	opti_write_reg(ap, data_rec_timing[clock][pio], WRITE_REG);
145 	opti_write_reg(ap, addr, MISC_REG);
146 
147 	/* Programming sequence complete, override strapping */
148 	opti_write_reg(ap, 0x85, CNTRL_REG);
149 }
150 
151 static struct scsi_host_template opti_sht = {
152 	ATA_PIO_SHT(DRV_NAME),
153 };
154 
155 static struct ata_port_operations opti_port_ops = {
156 	.inherits	= &ata_sff_port_ops,
157 	.cable_detect	= ata_cable_40wire,
158 	.set_piomode	= opti_set_piomode,
159 	.prereset	= opti_pre_reset,
160 };
161 
162 static int opti_init_one(struct pci_dev *dev, const struct pci_device_id *id)
163 {
164 	static const struct ata_port_info info = {
165 		.flags = ATA_FLAG_SLAVE_POSS,
166 		.pio_mask = ATA_PIO4,
167 		.port_ops = &opti_port_ops
168 	};
169 	const struct ata_port_info *ppi[] = { &info, NULL };
170 
171 	ata_print_version_once(&dev->dev, DRV_VERSION);
172 
173 	return ata_pci_sff_init_one(dev, ppi, &opti_sht, NULL, 0);
174 }
175 
176 static const struct pci_device_id opti[] = {
177 	{ PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C621), 0 },
178 	{ PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C825), 1 },
179 
180 	{ },
181 };
182 
183 static struct pci_driver opti_pci_driver = {
184 	.name 		= DRV_NAME,
185 	.id_table	= opti,
186 	.probe 		= opti_init_one,
187 	.remove		= ata_pci_remove_one,
188 #ifdef CONFIG_PM_SLEEP
189 	.suspend	= ata_pci_device_suspend,
190 	.resume		= ata_pci_device_resume,
191 #endif
192 };
193 
194 module_pci_driver(opti_pci_driver);
195 
196 MODULE_AUTHOR("Alan Cox");
197 MODULE_DESCRIPTION("low-level driver for Opti 621/621X");
198 MODULE_LICENSE("GPL");
199 MODULE_DEVICE_TABLE(pci, opti);
200 MODULE_VERSION(DRV_VERSION);
201