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 
sub22(char b,char c)52 static 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 
70 static DEFINE_SPINLOCK(dtc2278_lock);
71 
dtc2278_set_pio_mode(ide_hwif_t * hwif,ide_drive_t * drive)72 static 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 
91 static const struct ide_port_ops dtc2278_port_ops = {
92 	.set_pio_mode		= dtc2278_set_pio_mode,
93 };
94 
95 static 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 
dtc2278_probe(void)109 static 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 
134 static bool probe_dtc2278;
135 
136 module_param_named(probe, probe_dtc2278, bool, 0);
137 MODULE_PARM_DESC(probe, "probe for DTC2278xx chipsets");
138 
dtc2278_init(void)139 static 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 
151 module_init(dtc2278_init);
152 
153 MODULE_AUTHOR("See Local File");
154 MODULE_DESCRIPTION("support of DTC-2278 VLB IDE chipsets");
155 MODULE_LICENSE("GPL");
156