2 * Flash mappings described by the OF (or flattened) device tree
4 * Copyright (C) 2006 MontaVista Software Inc.
5 * Author: Vitaly Wool <vwool@ru.mvista.com>
7 * Revised to handle newer style flash binding by:
8 * Copyright (C) 2007 David Gibson, IBM Corporation.
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/init.h>
19 #include <linux/device.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/map.h>
22 #include <linux/mtd/partitions.h>
23 #include <linux/mtd/concat.h>
25 #include <linux/of_address.h>
26 #include <linux/of_platform.h>
27 #include <linux/slab.h>
29 struct of_flash_list
{
36 struct mtd_info
*cmtd
;
37 int list_size
; /* number of elements in of_flash_list */
38 struct of_flash_list list
[0];
41 static int of_flash_remove(struct platform_device
*dev
)
43 struct of_flash
*info
;
46 info
= dev_get_drvdata(&dev
->dev
);
49 dev_set_drvdata(&dev
->dev
, NULL
);
51 if (info
->cmtd
!= info
->list
[0].mtd
) {
52 mtd_device_unregister(info
->cmtd
);
53 mtd_concat_destroy(info
->cmtd
);
57 mtd_device_unregister(info
->cmtd
);
59 for (i
= 0; i
< info
->list_size
; i
++) {
60 if (info
->list
[i
].mtd
)
61 map_destroy(info
->list
[i
].mtd
);
63 if (info
->list
[i
].map
.virt
)
64 iounmap(info
->list
[i
].map
.virt
);
66 if (info
->list
[i
].res
) {
67 release_resource(info
->list
[i
].res
);
68 kfree(info
->list
[i
].res
);
77 /* Helper function to handle probing of the obsolete "direct-mapped"
78 * compatible binding, which has an extra "probe-type" property
79 * describing the type of flash probe necessary. */
80 static struct mtd_info
*obsolete_probe(struct platform_device
*dev
,
83 struct device_node
*dp
= dev
->dev
.of_node
;
86 static const char *rom_probe_types
[]
87 = { "cfi_probe", "jedec_probe", "map_rom"};
90 dev_warn(&dev
->dev
, "Device tree uses obsolete \"direct-mapped\" "
93 of_probe
= of_get_property(dp
, "probe-type", NULL
);
95 for (i
= 0; i
< ARRAY_SIZE(rom_probe_types
); i
++) {
96 mtd
= do_map_probe(rom_probe_types
[i
], map
);
101 } else if (strcmp(of_probe
, "CFI") == 0) {
102 return do_map_probe("cfi_probe", map
);
103 } else if (strcmp(of_probe
, "JEDEC") == 0) {
104 return do_map_probe("jedec_probe", map
);
106 if (strcmp(of_probe
, "ROM") != 0)
107 dev_warn(&dev
->dev
, "obsolete_probe: don't know probe "
108 "type '%s', mapping as rom\n", of_probe
);
109 return do_map_probe("mtd_rom", map
);
113 /* When partitions are set we look for a linux,part-probe property which
114 specifies the list of partition probers to use. If none is given then the
115 default is use. These take precedence over other device tree
117 static const char *part_probe_types_def
[] = { "cmdlinepart", "RedBoot",
118 "ofpart", "ofoldpart", NULL
};
119 static const char **of_get_probes(struct device_node
*dp
)
127 cp
= of_get_property(dp
, "linux,part-probe", &cplen
);
129 return part_probe_types_def
;
132 for (l
= 0; l
!= cplen
; l
++)
136 res
= kzalloc((count
+ 1)*sizeof(*res
), GFP_KERNEL
);
148 static void of_free_probes(const char **probes
)
150 if (probes
!= part_probe_types_def
)
154 static struct of_device_id of_flash_match
[];
155 static int of_flash_probe(struct platform_device
*dev
)
157 const char **part_probe_types
;
158 const struct of_device_id
*match
;
159 struct device_node
*dp
= dev
->dev
.of_node
;
161 struct of_flash
*info
;
162 const char *probe_type
;
169 struct mtd_info
**mtd_list
= NULL
;
170 resource_size_t res_size
;
171 struct mtd_part_parser_data ppdata
;
173 const char *mtd_name
;
175 match
= of_match_device(of_flash_match
, &dev
->dev
);
178 probe_type
= match
->data
;
180 reg_tuple_size
= (of_n_addr_cells(dp
) + of_n_size_cells(dp
)) * sizeof(u32
);
182 of_property_read_string(dp
, "linux,mtd-name", &mtd_name
);
185 * Get number of "reg" tuples. Scan for MTD devices on area's
186 * described by each "reg" region. This makes it possible (including
187 * the concat support) to support the Intel P30 48F4400 chips which
188 * consists internally of 2 non-identical NOR chips on one die.
190 p
= of_get_property(dp
, "reg", &count
);
191 if (count
% reg_tuple_size
!= 0) {
192 dev_err(&dev
->dev
, "Malformed reg property on %s\n",
193 dev
->dev
.of_node
->full_name
);
195 goto err_flash_remove
;
197 count
/= reg_tuple_size
;
199 map_indirect
= of_property_read_bool(dp
, "no-unaligned-direct-access");
202 info
= kzalloc(sizeof(struct of_flash
) +
203 sizeof(struct of_flash_list
) * count
, GFP_KERNEL
);
205 goto err_flash_remove
;
207 dev_set_drvdata(&dev
->dev
, info
);
209 mtd_list
= kzalloc(sizeof(*mtd_list
) * count
, GFP_KERNEL
);
211 goto err_flash_remove
;
213 for (i
= 0; i
< count
; i
++) {
215 if (of_address_to_resource(dp
, i
, &res
)) {
217 * Continue with next register tuple if this
218 * one is not mappable
223 dev_dbg(&dev
->dev
, "of_flash device: %pR\n", &res
);
226 res_size
= resource_size(&res
);
227 info
->list
[i
].res
= request_mem_region(res
.start
, res_size
,
228 dev_name(&dev
->dev
));
229 if (!info
->list
[i
].res
)
233 width
= of_get_property(dp
, "bank-width", NULL
);
235 dev_err(&dev
->dev
, "Can't get bank width from device"
240 info
->list
[i
].map
.name
= mtd_name
?: dev_name(&dev
->dev
);
241 info
->list
[i
].map
.phys
= res
.start
;
242 info
->list
[i
].map
.size
= res_size
;
243 info
->list
[i
].map
.bankwidth
= be32_to_cpup(width
);
246 info
->list
[i
].map
.virt
= ioremap(info
->list
[i
].map
.phys
,
247 info
->list
[i
].map
.size
);
248 if (!info
->list
[i
].map
.virt
) {
249 dev_err(&dev
->dev
, "Failed to ioremap() flash"
254 simple_map_init(&info
->list
[i
].map
);
257 * On some platforms (e.g. MPC5200) a direct 1:1 mapping
258 * may cause problems with JFFS2 usage, as the local bus (LPB)
259 * doesn't support unaligned accesses as implemented in the
260 * JFFS2 code via memcpy(). By setting NO_XIP, the
261 * flash will not be exposed directly to the MTD users
262 * (e.g. JFFS2) any more.
265 info
->list
[i
].map
.phys
= NO_XIP
;
268 info
->list
[i
].mtd
= do_map_probe(probe_type
,
271 info
->list
[i
].mtd
= obsolete_probe(dev
,
274 mtd_list
[i
] = info
->list
[i
].mtd
;
277 if (!info
->list
[i
].mtd
) {
278 dev_err(&dev
->dev
, "do_map_probe() failed\n");
283 info
->list
[i
].mtd
->owner
= THIS_MODULE
;
284 info
->list
[i
].mtd
->dev
.parent
= &dev
->dev
;
289 if (info
->list_size
== 1) {
290 info
->cmtd
= info
->list
[0].mtd
;
291 } else if (info
->list_size
> 1) {
293 * We detected multiple devices. Concatenate them together.
295 info
->cmtd
= mtd_concat_create(mtd_list
, info
->list_size
,
296 dev_name(&dev
->dev
));
298 if (info
->cmtd
== NULL
)
305 part_probe_types
= of_get_probes(dp
);
306 mtd_device_parse_register(info
->cmtd
, part_probe_types
, &ppdata
,
308 of_free_probes(part_probe_types
);
317 of_flash_remove(dev
);
322 static struct of_device_id of_flash_match
[] = {
324 .compatible
= "cfi-flash",
325 .data
= (void *)"cfi_probe",
328 /* FIXME: JEDEC chips can't be safely and reliably
329 * probed, although the mtd code gets it right in
330 * practice most of the time. We should use the
331 * vendor and device ids specified by the binding to
332 * bypass the heuristic probe code, but the mtd layer
333 * provides, at present, no interface for doing so
335 .compatible
= "jedec-flash",
336 .data
= (void *)"jedec_probe",
339 .compatible
= "mtd-ram",
340 .data
= (void *)"map_ram",
344 .compatible
= "direct-mapped"
348 MODULE_DEVICE_TABLE(of
, of_flash_match
);
350 static struct platform_driver of_flash_driver
= {
353 .owner
= THIS_MODULE
,
354 .of_match_table
= of_flash_match
,
356 .probe
= of_flash_probe
,
357 .remove
= of_flash_remove
,
360 module_platform_driver(of_flash_driver
);
362 MODULE_LICENSE("GPL");
363 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
364 MODULE_DESCRIPTION("Device tree based MTD map driver");