xref: /kernel/linux/linux-5.10/drivers/ide/dtc2278.c (revision 8c2ecf20) 
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  Copyright (C) 1996  Linus Torvalds & author (see below)
4 */
5
6#include <linux/module.h>
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <linux/delay.h>
10#include <linux/timer.h>
11#include <linux/mm.h>
12#include <linux/ioport.h>
13#include <linux/blkdev.h>
14#include <linux/ide.h>
15#include <linux/init.h>
16
17#include <asm/io.h>
18
19#define DRV_NAME "dtc2278"
20
21/*
22 * Changing this #undef to #define may solve start up problems in some systems.
23 */
24#undef ALWAYS_SET_DTC2278_PIO_MODE
25
26/*
27 * From: andy@cercle.cts.com (Dyan Wile)
28 *
29 * Below is a patch for DTC-2278 - alike software-programmable controllers
30 * The code enables the secondary IDE controller and the PIO4 (3?) timings on
31 * the primary (EIDE). You may probably have to enable the 32-bit support to
32 * get the full speed. You better get the disk interrupts disabled ( hdparm -u0
33 * /dev/hd.. ) for the drives connected to the EIDE interface. (I get my
34 * filesystem  corrupted with -u1, but under heavy disk load only :-)
35 *
36 * This card is now forced to use the "serialize" feature,
37 * and irq-unmasking is disallowed.  If io_32bit is enabled,
38 * it must be done for BOTH drives on each interface.
39 *
40 * This code was written for the DTC2278E, but might work with any of these:
41 *
42 * DTC2278S has only a single IDE interface.
43 * DTC2278D has two IDE interfaces and is otherwise identical to the S version.
44 * DTC2278E also has serial ports and a printer port
45 * DTC2278EB: has onboard BIOS, and "works like a charm" -- Kent Bradford <kent@theory.caltech.edu>
46 *
47 * There may be a fourth controller type. The S and D versions use the
48 * Winbond chip, and I think the E version does also.
49 *
50 */
51
52static void sub22 (char b, char c)
53{
54	int i;
55
56	for(i = 0; i < 3; ++i) {
57		inb(0x3f6);
58		outb_p(b,0xb0);
59		inb(0x3f6);
60		outb_p(c,0xb4);
61		inb(0x3f6);
62		if(inb(0xb4) == c) {
63			outb_p(7,0xb0);
64			inb(0x3f6);
65			return;	/* success */
66		}
67	}
68}
69
70static DEFINE_SPINLOCK(dtc2278_lock);
71
72static void dtc2278_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
73{
74	unsigned long flags;
75
76	if (drive->pio_mode >= XFER_PIO_3) {
77		spin_lock_irqsave(&dtc2278_lock, flags);
78		/*
79		 * This enables PIO mode4 (3?) on the first interface
80		 */
81		sub22(1,0xc3);
82		sub22(0,0xa0);
83		spin_unlock_irqrestore(&dtc2278_lock, flags);
84	} else {
85		/* we don't know how to set it back again.. */
86		/* Actually we do - there is a data sheet available for the
87		   Winbond but does anyone actually care */
88	}
89}
90
91static const struct ide_port_ops dtc2278_port_ops = {
92	.set_pio_mode		= dtc2278_set_pio_mode,
93};
94
95static const struct ide_port_info dtc2278_port_info __initconst = {
96	.name			= DRV_NAME,
97	.chipset		= ide_dtc2278,
98	.port_ops		= &dtc2278_port_ops,
99	.host_flags		= IDE_HFLAG_SERIALIZE |
100				  IDE_HFLAG_NO_UNMASK_IRQS |
101				  IDE_HFLAG_IO_32BIT |
102				  /* disallow ->io_32bit changes */
103				  IDE_HFLAG_NO_IO_32BIT |
104				  IDE_HFLAG_NO_DMA |
105				  IDE_HFLAG_DTC2278,
106	.pio_mask		= ATA_PIO4,
107};
108
109static int __init dtc2278_probe(void)
110{
111	unsigned long flags;
112
113	local_irq_save(flags);
114	/*
115	 * This enables the second interface
116	 */
117	outb_p(4,0xb0);
118	inb(0x3f6);
119	outb_p(0x20,0xb4);
120	inb(0x3f6);
121#ifdef ALWAYS_SET_DTC2278_PIO_MODE
122	/*
123	 * This enables PIO mode4 (3?) on the first interface
124	 * and may solve start-up problems for some people.
125	 */
126	sub22(1,0xc3);
127	sub22(0,0xa0);
128#endif
129	local_irq_restore(flags);
130
131	return ide_legacy_device_add(&dtc2278_port_info, 0);
132}
133
134static bool probe_dtc2278;
135
136module_param_named(probe, probe_dtc2278, bool, 0);
137MODULE_PARM_DESC(probe, "probe for DTC2278xx chipsets");
138
139static int __init dtc2278_init(void)
140{
141	if (probe_dtc2278 == 0)
142		return -ENODEV;
143
144	if (dtc2278_probe()) {
145		printk(KERN_ERR "dtc2278: ide interfaces already in use!\n");
146		return -EBUSY;
147	}
148	return 0;
149}
150
151module_init(dtc2278_init);
152
153MODULE_AUTHOR("See Local File");
154MODULE_DESCRIPTION("support of DTC-2278 VLB IDE chipsets");
155MODULE_LICENSE("GPL");
156