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17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/mtd/mtd.h>
21#include <linux/mtd/map.h>
22#include <linux/mtd/partitions.h>
23#include <linux/mtd/physmap.h>
24#include <linux/platform_device.h>
25#include <linux/slab.h>
26#include <linux/types.h>
27
28#include <asm/blackfin.h>
29#include <linux/gpio.h>
30#include <linux/io.h>
31#include <asm/unaligned.h>
32
33#define pr_devinit(fmt, args...) \
34 ({ static const char __fmt[] = fmt; printk(__fmt, ## args); })
35
36#define DRIVER_NAME "bfin-async-flash"
37
38struct async_state {
39 struct mtd_info *mtd;
40 struct map_info map;
41 int enet_flash_pin;
42 uint32_t flash_ambctl0, flash_ambctl1;
43 uint32_t save_ambctl0, save_ambctl1;
44 unsigned long irq_flags;
45};
46
47static void switch_to_flash(struct async_state *state)
48{
49 local_irq_save(state->irq_flags);
50
51 gpio_set_value(state->enet_flash_pin, 0);
52
53 state->save_ambctl0 = bfin_read_EBIU_AMBCTL0();
54 state->save_ambctl1 = bfin_read_EBIU_AMBCTL1();
55 bfin_write_EBIU_AMBCTL0(state->flash_ambctl0);
56 bfin_write_EBIU_AMBCTL1(state->flash_ambctl1);
57 SSYNC();
58}
59
60static void switch_back(struct async_state *state)
61{
62 bfin_write_EBIU_AMBCTL0(state->save_ambctl0);
63 bfin_write_EBIU_AMBCTL1(state->save_ambctl1);
64 SSYNC();
65
66 gpio_set_value(state->enet_flash_pin, 1);
67
68 local_irq_restore(state->irq_flags);
69}
70
71static map_word bfin_flash_read(struct map_info *map, unsigned long ofs)
72{
73 struct async_state *state = (struct async_state *)map->map_priv_1;
74 uint16_t word;
75 map_word test;
76
77 switch_to_flash(state);
78
79 word = readw(map->virt + ofs);
80
81 switch_back(state);
82
83 test.x[0] = word;
84 return test;
85}
86
87static void bfin_flash_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
88{
89 struct async_state *state = (struct async_state *)map->map_priv_1;
90
91 switch_to_flash(state);
92
93 memcpy(to, map->virt + from, len);
94
95 switch_back(state);
96}
97
98static void bfin_flash_write(struct map_info *map, map_word d1, unsigned long ofs)
99{
100 struct async_state *state = (struct async_state *)map->map_priv_1;
101 uint16_t d;
102
103 d = d1.x[0];
104
105 switch_to_flash(state);
106
107 writew(d, map->virt + ofs);
108 SSYNC();
109
110 switch_back(state);
111}
112
113static void bfin_flash_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
114{
115 struct async_state *state = (struct async_state *)map->map_priv_1;
116
117 switch_to_flash(state);
118
119 memcpy(map->virt + to, from, len);
120 SSYNC();
121
122 switch_back(state);
123}
124
125static const char * const part_probe_types[] = {
126 "cmdlinepart", "RedBoot", NULL };
127
128static int bfin_flash_probe(struct platform_device *pdev)
129{
130 int ret;
131 struct physmap_flash_data *pdata = pdev->dev.platform_data;
132 struct resource *memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
133 struct resource *flash_ambctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
134 struct async_state *state;
135
136 state = kzalloc(sizeof(*state), GFP_KERNEL);
137 if (!state)
138 return -ENOMEM;
139
140 state->map.name = DRIVER_NAME;
141 state->map.read = bfin_flash_read;
142 state->map.copy_from = bfin_flash_copy_from;
143 state->map.write = bfin_flash_write;
144 state->map.copy_to = bfin_flash_copy_to;
145 state->map.bankwidth = pdata->width;
146 state->map.size = resource_size(memory);
147 state->map.virt = (void __iomem *)memory->start;
148 state->map.phys = memory->start;
149 state->map.map_priv_1 = (unsigned long)state;
150 state->enet_flash_pin = platform_get_irq(pdev, 0);
151 state->flash_ambctl0 = flash_ambctl->start;
152 state->flash_ambctl1 = flash_ambctl->end;
153
154 if (gpio_request(state->enet_flash_pin, DRIVER_NAME)) {
155 pr_devinit(KERN_ERR DRIVER_NAME ": Failed to request gpio %d\n", state->enet_flash_pin);
156 kfree(state);
157 return -EBUSY;
158 }
159 gpio_direction_output(state->enet_flash_pin, 1);
160
161 pr_devinit(KERN_NOTICE DRIVER_NAME ": probing %d-bit flash bus\n", state->map.bankwidth * 8);
162 state->mtd = do_map_probe(memory->name, &state->map);
163 if (!state->mtd) {
164 gpio_free(state->enet_flash_pin);
165 kfree(state);
166 return -ENXIO;
167 }
168
169 mtd_device_parse_register(state->mtd, part_probe_types, NULL,
170 pdata->parts, pdata->nr_parts);
171
172 platform_set_drvdata(pdev, state);
173
174 return 0;
175}
176
177static int bfin_flash_remove(struct platform_device *pdev)
178{
179 struct async_state *state = platform_get_drvdata(pdev);
180 gpio_free(state->enet_flash_pin);
181 mtd_device_unregister(state->mtd);
182 map_destroy(state->mtd);
183 kfree(state);
184 return 0;
185}
186
187static struct platform_driver bfin_flash_driver = {
188 .probe = bfin_flash_probe,
189 .remove = bfin_flash_remove,
190 .driver = {
191 .name = DRIVER_NAME,
192 },
193};
194
195module_platform_driver(bfin_flash_driver);
196
197MODULE_LICENSE("GPL");
198MODULE_DESCRIPTION("MTD map driver for Blackfins with flash/ethernet on same async bank");
199
