2 * This program is free software; you can redistribute it and/or modify it
3 * under the terms of the GNU General Public License version 2 as published
4 * by the Free Software Foundation.
6 * Copyright (C) 2004 Liu Peng Infineon IFAP DC COM CPE
7 * Copyright (C) 2010 John Crispin <blogic@openwrt.org>
10 #include <linux/err.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/map.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/mtd/cfi.h>
21 #include <linux/platform_device.h>
22 #include <linux/mtd/physmap.h>
25 #include <lantiq_soc.h>
28 * The NOR flash is connected to the same external bus unit (EBU) as PCI.
29 * To make PCI work we need to enable the endianness swapping for the address
30 * written to the EBU. This endianness swapping works for PCI correctly but
31 * fails for attached NOR devices. To workaround this we need to use a complex
32 * map. The workaround involves swapping all addresses whilst probing the chip.
33 * Once probing is complete we stop swapping the addresses but swizzle the
34 * unlock addresses to ensure that access to the NOR device works correctly.
48 static const char ltq_map_name[] = "ltq_nor";
49 static const char * const ltq_probe_types[] = { "cmdlinepart", "ofpart", NULL };
52 ltq_read16(struct map_info *map, unsigned long adr)
57 if (map->map_priv_1 == LTQ_NOR_PROBING)
59 spin_lock_irqsave(&ebu_lock, flags);
60 temp.x[0] = *(u16 *)(map->virt + adr);
61 spin_unlock_irqrestore(&ebu_lock, flags);
66 ltq_write16(struct map_info *map, map_word d, unsigned long adr)
70 if (map->map_priv_1 == LTQ_NOR_PROBING)
72 spin_lock_irqsave(&ebu_lock, flags);
73 *(u16 *)(map->virt + adr) = d.x[0];
74 spin_unlock_irqrestore(&ebu_lock, flags);
78 * The following 2 functions copy data between iomem and a cached memory
79 * section. As memcpy() makes use of pre-fetching we cannot use it here.
80 * The normal alternative of using memcpy_{to,from}io also makes use of
81 * memcpy() on MIPS so it is not applicable either. We are therefore stuck
82 * with having to use our own loop.
85 ltq_copy_from(struct map_info *map, void *to,
86 unsigned long from, ssize_t len)
88 unsigned char *f = (unsigned char *)map->virt + from;
89 unsigned char *t = (unsigned char *)to;
92 spin_lock_irqsave(&ebu_lock, flags);
95 spin_unlock_irqrestore(&ebu_lock, flags);
99 ltq_copy_to(struct map_info *map, unsigned long to,
100 const void *from, ssize_t len)
102 unsigned char *f = (unsigned char *)from;
103 unsigned char *t = (unsigned char *)map->virt + to;
106 spin_lock_irqsave(&ebu_lock, flags);
109 spin_unlock_irqrestore(&ebu_lock, flags);
113 ltq_mtd_probe(struct platform_device *pdev)
115 struct mtd_part_parser_data ppdata;
116 struct ltq_mtd *ltq_mtd;
117 struct cfi_private *cfi;
120 if (of_machine_is_compatible("lantiq,falcon") &&
121 (ltq_boot_select() != BS_FLASH)) {
122 dev_err(&pdev->dev, "invalid bootstrap options\n");
126 ltq_mtd = kzalloc(sizeof(struct ltq_mtd), GFP_KERNEL);
127 platform_set_drvdata(pdev, ltq_mtd);
129 ltq_mtd->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
131 dev_err(&pdev->dev, "failed to get memory resource\n");
136 ltq_mtd->map = kzalloc(sizeof(struct map_info), GFP_KERNEL);
137 ltq_mtd->map->phys = ltq_mtd->res->start;
138 ltq_mtd->map->size = resource_size(ltq_mtd->res);
139 ltq_mtd->map->virt = devm_ioremap_resource(&pdev->dev, ltq_mtd->res);
140 if (IS_ERR(ltq_mtd->map->virt)) {
141 err = PTR_ERR(ltq_mtd->map->virt);
145 ltq_mtd->map->name = ltq_map_name;
146 ltq_mtd->map->bankwidth = 2;
147 ltq_mtd->map->read = ltq_read16;
148 ltq_mtd->map->write = ltq_write16;
149 ltq_mtd->map->copy_from = ltq_copy_from;
150 ltq_mtd->map->copy_to = ltq_copy_to;
152 ltq_mtd->map->map_priv_1 = LTQ_NOR_PROBING;
153 ltq_mtd->mtd = do_map_probe("cfi_probe", ltq_mtd->map);
154 ltq_mtd->map->map_priv_1 = LTQ_NOR_NORMAL;
157 dev_err(&pdev->dev, "probing failed\n");
162 ltq_mtd->mtd->owner = THIS_MODULE;
164 cfi = ltq_mtd->map->fldrv_priv;
165 cfi->addr_unlock1 ^= 1;
166 cfi->addr_unlock2 ^= 1;
168 ppdata.of_node = pdev->dev.of_node;
169 err = mtd_device_parse_register(ltq_mtd->mtd, ltq_probe_types,
172 dev_err(&pdev->dev, "failed to add partitions\n");
179 map_destroy(ltq_mtd->mtd);
188 ltq_mtd_remove(struct platform_device *pdev)
190 struct ltq_mtd *ltq_mtd = platform_get_drvdata(pdev);
194 mtd_device_unregister(ltq_mtd->mtd);
195 map_destroy(ltq_mtd->mtd);
203 static const struct of_device_id ltq_mtd_match[] = {
204 { .compatible = "lantiq,nor" },
207 MODULE_DEVICE_TABLE(of, ltq_mtd_match);
209 static struct platform_driver ltq_mtd_driver = {
210 .probe = ltq_mtd_probe,
211 .remove = ltq_mtd_remove,
214 .owner = THIS_MODULE,
215 .of_match_table = ltq_mtd_match,
219 module_platform_driver(ltq_mtd_driver);
221 MODULE_LICENSE("GPL");
222 MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
223 MODULE_DESCRIPTION("Lantiq SoC NOR");