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/module.h>
11 #include <linux/types.h>
12 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/map.h>
18 #include <linux/mtd/partitions.h>
19 #include <linux/mtd/cfi.h>
20 #include <linux/platform_device.h>
21 #include <linux/mtd/physmap.h>
23 #include <lantiq_soc.h>
24 #include <lantiq_platform.h>
27 * The NOR flash is connected to the same external bus unit (EBU) as PCI.
28 * To make PCI work we need to enable the endianness swapping for the address
29 * written to the EBU. This endianness swapping works for PCI correctly but
30 * fails for attached NOR devices. To workaround this we need to use a complex
31 * map. The workaround involves swapping all addresses whilst probing the chip.
32 * Once probing is complete we stop swapping the addresses but swizzle the
33 * unlock addresses to ensure that access to the NOR device works correctly.
47 static char ltq_map_name
[] = "ltq_nor";
50 ltq_read16(struct map_info
*map
, unsigned long adr
)
55 if (map
->map_priv_1
== LTQ_NOR_PROBING
)
57 spin_lock_irqsave(&ebu_lock
, flags
);
58 temp
.x
[0] = *(u16
*)(map
->virt
+ adr
);
59 spin_unlock_irqrestore(&ebu_lock
, flags
);
64 ltq_write16(struct map_info
*map
, map_word d
, unsigned long adr
)
68 if (map
->map_priv_1
== LTQ_NOR_PROBING
)
70 spin_lock_irqsave(&ebu_lock
, flags
);
71 *(u16
*)(map
->virt
+ adr
) = d
.x
[0];
72 spin_unlock_irqrestore(&ebu_lock
, flags
);
76 * The following 2 functions copy data between iomem and a cached memory
77 * section. As memcpy() makes use of pre-fetching we cannot use it here.
78 * The normal alternative of using memcpy_{to,from}io also makes use of
79 * memcpy() on MIPS so it is not applicable either. We are therefore stuck
80 * with having to use our own loop.
83 ltq_copy_from(struct map_info
*map
, void *to
,
84 unsigned long from
, ssize_t len
)
86 unsigned char *f
= (unsigned char *)map
->virt
+ from
;
87 unsigned char *t
= (unsigned char *)to
;
90 spin_lock_irqsave(&ebu_lock
, flags
);
93 spin_unlock_irqrestore(&ebu_lock
, flags
);
97 ltq_copy_to(struct map_info
*map
, unsigned long to
,
98 const void *from
, ssize_t len
)
100 unsigned char *f
= (unsigned char *)from
;
101 unsigned char *t
= (unsigned char *)map
->virt
+ to
;
104 spin_lock_irqsave(&ebu_lock
, flags
);
107 spin_unlock_irqrestore(&ebu_lock
, flags
);
111 ltq_mtd_probe(struct platform_device
*pdev
)
113 struct physmap_flash_data
*ltq_mtd_data
= dev_get_platdata(&pdev
->dev
);
114 struct ltq_mtd
*ltq_mtd
;
115 struct resource
*res
;
116 struct cfi_private
*cfi
;
119 ltq_mtd
= kzalloc(sizeof(struct ltq_mtd
), GFP_KERNEL
);
120 platform_set_drvdata(pdev
, ltq_mtd
);
122 ltq_mtd
->res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
124 dev_err(&pdev
->dev
, "failed to get memory resource");
129 res
= devm_request_mem_region(&pdev
->dev
, ltq_mtd
->res
->start
,
130 resource_size(ltq_mtd
->res
), dev_name(&pdev
->dev
));
132 dev_err(&pdev
->dev
, "failed to request mem resource");
137 ltq_mtd
->map
= kzalloc(sizeof(struct map_info
), GFP_KERNEL
);
138 ltq_mtd
->map
->phys
= res
->start
;
139 ltq_mtd
->map
->size
= resource_size(res
);
140 ltq_mtd
->map
->virt
= devm_ioremap_nocache(&pdev
->dev
,
141 ltq_mtd
->map
->phys
, ltq_mtd
->map
->size
);
142 if (!ltq_mtd
->map
->virt
) {
143 dev_err(&pdev
->dev
, "failed to ioremap!\n");
148 ltq_mtd
->map
->name
= ltq_map_name
;
149 ltq_mtd
->map
->bankwidth
= 2;
150 ltq_mtd
->map
->read
= ltq_read16
;
151 ltq_mtd
->map
->write
= ltq_write16
;
152 ltq_mtd
->map
->copy_from
= ltq_copy_from
;
153 ltq_mtd
->map
->copy_to
= ltq_copy_to
;
155 ltq_mtd
->map
->map_priv_1
= LTQ_NOR_PROBING
;
156 ltq_mtd
->mtd
= do_map_probe("cfi_probe", ltq_mtd
->map
);
157 ltq_mtd
->map
->map_priv_1
= LTQ_NOR_NORMAL
;
160 dev_err(&pdev
->dev
, "probing failed\n");
165 ltq_mtd
->mtd
->owner
= THIS_MODULE
;
167 cfi
= ltq_mtd
->map
->fldrv_priv
;
168 cfi
->addr_unlock1
^= 1;
169 cfi
->addr_unlock2
^= 1;
171 err
= mtd_device_parse_register(ltq_mtd
->mtd
, NULL
, 0,
172 ltq_mtd_data
->parts
, ltq_mtd_data
->nr_parts
);
174 dev_err(&pdev
->dev
, "failed to add partitions\n");
181 map_destroy(ltq_mtd
->mtd
);
190 ltq_mtd_remove(struct platform_device
*pdev
)
192 struct ltq_mtd
*ltq_mtd
= platform_get_drvdata(pdev
);
196 mtd_device_unregister(ltq_mtd
->mtd
);
197 map_destroy(ltq_mtd
->mtd
);
205 static struct platform_driver ltq_mtd_driver
= {
206 .remove
= __devexit_p(ltq_mtd_remove
),
209 .owner
= THIS_MODULE
,
216 int ret
= platform_driver_probe(<q_mtd_driver
, ltq_mtd_probe
);
219 pr_err("ltq_nor: error registering platform driver");
226 platform_driver_unregister(<q_mtd_driver
);
229 module_init(init_ltq_mtd
);
230 module_exit(exit_ltq_mtd
);
232 MODULE_LICENSE("GPL");
233 MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
234 MODULE_DESCRIPTION("Lantiq SoC NOR");