xref: /kernel/linux/linux-5.10/drivers/dio/dio.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/* Code to support devices on the DIO and DIO-II bus
3 * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk>
4 * Copyright (C) 2004 Jochen Friedrich <jochen@scram.de>
5 *
6 * This code has basically these routines at the moment:
7 * int dio_find(u_int deviceid)
8 *    Search the list of DIO devices and return the select code
9 *    of the next unconfigured device found that matches the given device ID.
10 *    Note that the deviceid parameter should be the encoded ID.
11 *    This means that framebuffers should pass it as
12 *    DIO_ENCODE_ID(DIO_ID_FBUFFER,DIO_ID2_TOPCAT)
13 *    (or whatever); everybody else just uses DIO_ID_FOOBAR.
14 * unsigned long dio_scodetophysaddr(int scode)
15 *    Return the physical address corresponding to the given select code.
16 * int dio_scodetoipl(int scode)
17 *    Every DIO card has a fixed interrupt priority level. This function
18 *    returns it, whatever it is.
19 * const char *dio_scodetoname(int scode)
20 *    Return a character string describing this board [might be "" if
21 *    not CONFIG_DIO_CONSTANTS]
22 * void dio_config_board(int scode)     mark board as configured in the list
23 * void dio_unconfig_board(int scode)   mark board as no longer configured
24 *
25 * This file is based on the way the Amiga port handles Zorro II cards,
26 * although we aren't so complicated...
27 */
28#include <linux/module.h>
29#include <linux/string.h>
30#include <linux/types.h>
31#include <linux/kernel.h>
32#include <linux/init.h>
33#include <linux/dio.h>
34#include <linux/slab.h>                         /* kmalloc() */
35#include <linux/uaccess.h>
36#include <asm/io.h>                             /* readb() */
37
38struct dio_bus dio_bus = {
39	.resources = {
40		/* DIO range */
41		{ .name = "DIO mem", .start = 0x00600000, .end = 0x007fffff },
42		/* DIO-II range */
43		{ .name = "DIO-II mem", .start = 0x01000000, .end = 0x1fffffff }
44	},
45	.name = "DIO bus"
46};
47
48/* not a real config option yet! */
49#define CONFIG_DIO_CONSTANTS
50
51#ifdef CONFIG_DIO_CONSTANTS
52/* We associate each numeric ID with an appropriate descriptive string
53 * using a constant array of these structs.
54 * FIXME: we should be able to arrange to throw away most of the strings
55 * using the initdata stuff. Then we wouldn't need to worry about
56 * carrying them around...
57 * I think we do this by copying them into newly kmalloc()ed memory and
58 * marking the names[] array as .initdata ?
59 */
60struct dioname
61{
62        int id;
63        const char *name;
64};
65
66/* useful macro */
67#define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x }
68#define DIOFBNAME(x) { DIO_ENCODE_ID( DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x }
69
70static struct dioname names[] =
71{
72        DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM),
73        DIONAME(DCM), DIONAME(DCMREM),
74        DIONAME(LAN),
75        DIONAME(FHPIB), DIONAME(NHPIB),
76        DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3),
77        DIONAME(FBUFFER),
78        DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM),
79        DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3),
80        DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7),
81        DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11),
82        DIONAME(MISC12), DIONAME(MISC13),
83        DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE),
84        DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE),
85        DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION),
86        DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS)
87};
88
89#undef DIONAME
90#undef DIOFBNAME
91
92static const char unknowndioname[]
93	= "unknown DIO board, please email linux-m68k@lists.linux-m68k.org";
94
95static const char *dio_getname(int id)
96{
97        /* return pointer to a constant string describing the board with given ID */
98	unsigned int i;
99	for (i = 0; i < ARRAY_SIZE(names); i++)
100                if (names[i].id == id)
101                        return names[i].name;
102
103        return unknowndioname;
104}
105
106#else
107
108static char dio_no_name[] = { 0 };
109#define dio_getname(_id)	(dio_no_name)
110
111#endif /* CONFIG_DIO_CONSTANTS */
112
113static void dio_dev_release(struct device *dev)
114{
115	struct dio_dev *ddev = container_of(dev, typeof(struct dio_dev), dev);
116	kfree(ddev);
117}
118
119int __init dio_find(int deviceid)
120{
121	/* Called to find a DIO device before the full bus scan has run.
122	 * Only used by the console driver.
123	 */
124	int scode, id;
125	u_char prid, secid, i;
126
127	for (scode = 0; scode < DIO_SCMAX; scode++) {
128		void *va;
129		unsigned long pa;
130
131                if (DIO_SCINHOLE(scode))
132                        continue;
133
134                pa = dio_scodetophysaddr(scode);
135
136		if (!pa)
137			continue;
138
139		if (scode < DIOII_SCBASE)
140			va = (void *)(pa + DIO_VIRADDRBASE);
141		else
142			va = ioremap(pa, PAGE_SIZE);
143
144		if (copy_from_kernel_nofault(&i,
145				(unsigned char *)va + DIO_IDOFF, 1)) {
146			if (scode >= DIOII_SCBASE)
147				iounmap(va);
148                        continue;             /* no board present at that select code */
149		}
150
151		prid = DIO_ID(va);
152
153                if (DIO_NEEDSSECID(prid)) {
154                        secid = DIO_SECID(va);
155                        id = DIO_ENCODE_ID(prid, secid);
156                } else
157			id = prid;
158
159		if (id == deviceid) {
160			if (scode >= DIOII_SCBASE)
161				iounmap(va);
162			return scode;
163		}
164	}
165
166	return -1;
167}
168
169/* This is the function that scans the DIO space and works out what
170 * hardware is actually present.
171 */
172static int __init dio_init(void)
173{
174	int scode;
175	int i;
176	struct dio_dev *dev;
177	int error;
178
179	if (!MACH_IS_HP300)
180		return 0;
181
182        printk(KERN_INFO "Scanning for DIO devices...\n");
183
184	/* Initialize the DIO bus */
185	INIT_LIST_HEAD(&dio_bus.devices);
186	dev_set_name(&dio_bus.dev, "dio");
187	error = device_register(&dio_bus.dev);
188	if (error) {
189		pr_err("DIO: Error registering dio_bus\n");
190		return error;
191	}
192
193	/* Request all resources */
194	dio_bus.num_resources = (hp300_model == HP_320 ? 1 : 2);
195	for (i = 0; i < dio_bus.num_resources; i++)
196		request_resource(&iomem_resource, &dio_bus.resources[i]);
197
198	/* Register all devices */
199        for (scode = 0; scode < DIO_SCMAX; ++scode)
200        {
201                u_char prid, secid = 0;        /* primary, secondary ID bytes */
202                u_char *va;
203		unsigned long pa;
204
205                if (DIO_SCINHOLE(scode))
206                        continue;
207
208		pa = dio_scodetophysaddr(scode);
209
210		if (!pa)
211			continue;
212
213		if (scode < DIOII_SCBASE)
214			va = (void *)(pa + DIO_VIRADDRBASE);
215		else
216			va = ioremap(pa, PAGE_SIZE);
217
218		if (copy_from_kernel_nofault(&i,
219				(unsigned char *)va + DIO_IDOFF, 1)) {
220			if (scode >= DIOII_SCBASE)
221				iounmap(va);
222                        continue;              /* no board present at that select code */
223		}
224
225                /* Found a board, allocate it an entry in the list */
226		dev = kzalloc(sizeof(struct dio_dev), GFP_KERNEL);
227		if (!dev)
228			return 0;
229
230		dev->bus = &dio_bus;
231		dev->dev.parent = &dio_bus.dev;
232		dev->dev.bus = &dio_bus_type;
233		dev->dev.release = dio_dev_release;
234		dev->scode = scode;
235		dev->resource.start = pa;
236		dev->resource.end = pa + DIO_SIZE(scode, va);
237		dev_set_name(&dev->dev, "%02x", scode);
238
239                /* read the ID byte(s) and encode if necessary. */
240		prid = DIO_ID(va);
241
242                if (DIO_NEEDSSECID(prid)) {
243                        secid = DIO_SECID(va);
244                        dev->id = DIO_ENCODE_ID(prid, secid);
245                } else
246                        dev->id = prid;
247
248                dev->ipl = DIO_IPL(va);
249                strcpy(dev->name,dio_getname(dev->id));
250                printk(KERN_INFO "select code %3d: ipl %d: ID %02X", dev->scode, dev->ipl, prid);
251                if (DIO_NEEDSSECID(prid))
252                        printk(":%02X", secid);
253                printk(": %s\n", dev->name);
254
255		if (scode >= DIOII_SCBASE)
256			iounmap(va);
257		error = device_register(&dev->dev);
258		if (error) {
259			pr_err("DIO: Error registering device %s\n",
260			       dev->name);
261			put_device(&dev->dev);
262			continue;
263		}
264		error = dio_create_sysfs_dev_files(dev);
265		if (error)
266			dev_err(&dev->dev, "Error creating sysfs files\n");
267        }
268	return 0;
269}
270
271subsys_initcall(dio_init);
272
273/* Bear in mind that this is called in the very early stages of initialisation
274 * in order to get the address of the serial port for the console...
275 */
276unsigned long dio_scodetophysaddr(int scode)
277{
278        if (scode >= DIOII_SCBASE) {
279                return (DIOII_BASE + (scode - 132) * DIOII_DEVSIZE);
280        } else if (scode > DIO_SCMAX || scode < 0)
281                return 0;
282        else if (DIO_SCINHOLE(scode))
283                return 0;
284
285        return (DIO_BASE + scode * DIO_DEVSIZE);
286}
287