1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/mtd/mtd.h>
20#include <linux/mtd/map.h>
21#include <linux/mtd/partitions.h>
22#include <linux/mtd/physmap.h>
23#include <linux/platform_device.h>
24#include <linux/slab.h>
25#include <linux/types.h>
26
27#include <asm/blackfin.h>
28#include <linux/gpio.h>
29#include <linux/io.h>
30#include <asm/unaligned.h>
31
32#define pr_devinit(fmt, args...) \
33 ({ static const char __fmt[] = fmt; printk(__fmt, ## args); })
34
35#define DRIVER_NAME "bfin-async-flash"
36
37struct async_state {
38 struct mtd_info *mtd;
39 struct map_info map;
40 int enet_flash_pin;
41 uint32_t flash_ambctl0, flash_ambctl1;
42 uint32_t save_ambctl0, save_ambctl1;
43 unsigned long irq_flags;
44};
45
46static void switch_to_flash(struct async_state *state)
47{
48 local_irq_save(state->irq_flags);
49
50 gpio_set_value(state->enet_flash_pin, 0);
51
52 state->save_ambctl0 = bfin_read_EBIU_AMBCTL0();
53 state->save_ambctl1 = bfin_read_EBIU_AMBCTL1();
54 bfin_write_EBIU_AMBCTL0(state->flash_ambctl0);
55 bfin_write_EBIU_AMBCTL1(state->flash_ambctl1);
56 SSYNC();
57}
58
59static void switch_back(struct async_state *state)
60{
61 bfin_write_EBIU_AMBCTL0(state->save_ambctl0);
62 bfin_write_EBIU_AMBCTL1(state->save_ambctl1);
63 SSYNC();
64
65 gpio_set_value(state->enet_flash_pin, 1);
66
67 local_irq_restore(state->irq_flags);
68}
69
70static map_word bfin_flash_read(struct map_info *map, unsigned long ofs)
71{
72 struct async_state *state = (struct async_state *)map->map_priv_1;
73 uint16_t word;
74 map_word test;
75
76 switch_to_flash(state);
77
78 word = readw(map->virt + ofs);
79
80 switch_back(state);
81
82 test.x[0] = word;
83 return test;
84}
85
86static void bfin_flash_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
87{
88 struct async_state *state = (struct async_state *)map->map_priv_1;
89
90 switch_to_flash(state);
91
92 memcpy(to, map->virt + from, len);
93
94 switch_back(state);
95}
96
97static void bfin_flash_write(struct map_info *map, map_word d1, unsigned long ofs)
98{
99 struct async_state *state = (struct async_state *)map->map_priv_1;
100 uint16_t d;
101
102 d = d1.x[0];
103
104 switch_to_flash(state);
105
106 writew(d, map->virt + ofs);
107 SSYNC();
108
109 switch_back(state);
110}
111
112static void bfin_flash_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
113{
114 struct async_state *state = (struct async_state *)map->map_priv_1;
115
116 switch_to_flash(state);
117
118 memcpy(map->virt + to, from, len);
119 SSYNC();
120
121 switch_back(state);
122}
123
124static const char * const part_probe_types[] = {
125 "cmdlinepart", "RedBoot", NULL };
126
127static int bfin_flash_probe(struct platform_device *pdev)
128{
129 struct physmap_flash_data *pdata = dev_get_platdata(&pdev->dev);
130 struct resource *memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
131 struct resource *flash_ambctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
132 struct async_state *state;
133
134 state = kzalloc(sizeof(*state), GFP_KERNEL);
135 if (!state)
136 return -ENOMEM;
137
138 state->map.name = DRIVER_NAME;
139 state->map.read = bfin_flash_read;
140 state->map.copy_from = bfin_flash_copy_from;
141 state->map.write = bfin_flash_write;
142 state->map.copy_to = bfin_flash_copy_to;
143 state->map.bankwidth = pdata->width;
144 state->map.size = resource_size(memory);
145 state->map.virt = (void __iomem *)memory->start;
146 state->map.phys = memory->start;
147 state->map.map_priv_1 = (unsigned long)state;
148 state->enet_flash_pin = platform_get_irq(pdev, 0);
149 state->flash_ambctl0 = flash_ambctl->start;
150 state->flash_ambctl1 = flash_ambctl->end;
151
152 if (gpio_request(state->enet_flash_pin, DRIVER_NAME)) {
153 pr_devinit(KERN_ERR DRIVER_NAME ": Failed to request gpio %d\n", state->enet_flash_pin);
154 kfree(state);
155 return -EBUSY;
156 }
157 gpio_direction_output(state->enet_flash_pin, 1);
158
159 pr_devinit(KERN_NOTICE DRIVER_NAME ": probing %d-bit flash bus\n", state->map.bankwidth * 8);
160 state->mtd = do_map_probe(memory->name, &state->map);
161 if (!state->mtd) {
162 gpio_free(state->enet_flash_pin);
163 kfree(state);
164 return -ENXIO;
165 }
166
167 mtd_device_parse_register(state->mtd, part_probe_types, NULL,
168 pdata->parts, pdata->nr_parts);
169
170 platform_set_drvdata(pdev, state);
171
172 return 0;
173}
174
175static int bfin_flash_remove(struct platform_device *pdev)
176{
177 struct async_state *state = platform_get_drvdata(pdev);
178 gpio_free(state->enet_flash_pin);
179 mtd_device_unregister(state->mtd);
180 map_destroy(state->mtd);
181 kfree(state);
182 return 0;
183}
184
185static struct platform_driver bfin_flash_driver = {
186 .probe = bfin_flash_probe,
187 .remove = bfin_flash_remove,
188 .driver = {
189 .name = DRIVER_NAME,
190 },
191};
192
193module_platform_driver(bfin_flash_driver);
194
195MODULE_LICENSE("GPL");
196MODULE_DESCRIPTION("MTD map driver for Blackfins with flash/ethernet on same async bank");
197
