1/*
2 *  linux/drivers/ide/dtc2278.c		Version 0.02	Feb 10, 1996
3 *
4 *  Copyright (C) 1996  Linus Torvalds & author (see below)
5 */
6
7#undef REALLY_SLOW_IO           /* most systems can safely undef this */
8
9#include <linux/types.h>
10#include <linux/kernel.h>
11#include <linux/delay.h>
12#include <linux/timer.h>
13#include <linux/mm.h>
14#include <linux/ioport.h>
15#include <linux/blkdev.h>
16#include <linux/hdreg.h>
17#include <linux/ide.h>
18#include <linux/init.h>
19
20#include <asm/io.h>
21
22#include "ide_modes.h"
23
24/*
25 * Changing this #undef to #define may solve start up problems in some systems.
26 */
27#undef ALWAYS_SET_DTC2278_PIO_MODE
28
29/*
30 * From: andy@cercle.cts.com (Dyan Wile)
31 *
32 * Below is a patch for DTC-2278 - alike software-programmable controllers
33 * The code enables the secondary IDE controller and the PIO4 (3?) timings on
34 * the primary (EIDE). You may probably have to enable the 32-bit support to
35 * get the full speed. You better get the disk interrupts disabled ( hdparm -u0
36 * /dev/hd.. ) for the drives connected to the EIDE interface. (I get my
37 * filesystem  corrupted with -u1, but under heavy disk load only :-)
38 *
39 * This card is now forced to use the "serialize" feature,
40 * and irq-unmasking is disallowed.  If io_32bit is enabled,
41 * it must be done for BOTH drives on each interface.
42 *
43 * This code was written for the DTC2278E, but might work with any of these:
44 *
45 * DTC2278S has only a single IDE interface.
46 * DTC2278D has two IDE interfaces and is otherwise identical to the S version.
47 * DTC2278E also has serial ports and a printer port
48 * DTC2278EB: has onboard BIOS, and "works like a charm" -- Kent Bradford <kent@theory.caltech.edu>
49 *
50 * There may be a fourth controller type. The S and D versions use the
51 * Winbond chip, and I think the E version does also.
52 *
53 */
54
55static void sub22 (char b, char c)
56{
57	int i;
58
59	for(i = 0; i < 3; ++i) {
60		inb(0x3f6);
61		outb_p(b,0xb0);
62		inb(0x3f6);
63		outb_p(c,0xb4);
64		inb(0x3f6);
65		if(inb(0xb4) == c) {
66			outb_p(7,0xb0);
67			inb(0x3f6);
68			return;	/* success */
69		}
70	}
71}
72
73static void tune_dtc2278 (ide_drive_t *drive, byte pio)
74{
75	unsigned long flags;
76
77	pio = ide_get_best_pio_mode(drive, pio, 4, NULL);
78
79	if (pio >= 3) {
80		save_flags(flags);	/* all CPUs */
81		cli();			/* all CPUs */
82		/*
83		 * This enables PIO mode4 (3?) on the first interface
84		 */
85		sub22(1,0xc3);
86		sub22(0,0xa0);
87		restore_flags(flags);	/* all CPUs */
88	} else {
89		/* we don't know how to set it back again.. */
90	}
91
92	/*
93	 * 32bit I/O has to be enabled for *both* drives at the same time.
94	 */
95	drive->io_32bit = 1;
96	HWIF(drive)->drives[!drive->select.b.unit].io_32bit = 1;
97}
98
99void __init init_dtc2278 (void)
100{
101	unsigned long flags;
102
103	__save_flags(flags);	/* local CPU only */
104	__cli();		/* local CPU only */
105	/*
106	 * This enables the second interface
107	 */
108	outb_p(4,0xb0);
109	inb(0x3f6);
110	outb_p(0x20,0xb4);
111	inb(0x3f6);
112#ifdef ALWAYS_SET_DTC2278_PIO_MODE
113	/*
114	 * This enables PIO mode4 (3?) on the first interface
115	 * and may solve start-up problems for some people.
116	 */
117	sub22(1,0xc3);
118	sub22(0,0xa0);
119#endif
120	__restore_flags(flags);	/* local CPU only */
121
122	ide_hwifs[0].serialized = 1;
123	ide_hwifs[1].serialized = 1;
124	ide_hwifs[0].chipset = ide_dtc2278;
125	ide_hwifs[1].chipset = ide_dtc2278;
126	ide_hwifs[0].tuneproc = &tune_dtc2278;
127	ide_hwifs[0].drives[0].no_unmask = 1;
128	ide_hwifs[0].drives[1].no_unmask = 1;
129	ide_hwifs[1].drives[0].no_unmask = 1;
130	ide_hwifs[1].drives[1].no_unmask = 1;
131	ide_hwifs[0].mate = &ide_hwifs[1];
132	ide_hwifs[1].mate = &ide_hwifs[0];
133	ide_hwifs[1].channel = 1;
134}
135