1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Flash memory access on SA11x0 based devices |
4 | * |
5 | * (C) 2000 Nicolas Pitre <nico@fluxnic.net> |
6 | */ |
7 | #include <linux/module.h> |
8 | #include <linux/types.h> |
9 | #include <linux/ioport.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/init.h> |
12 | #include <linux/errno.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/platform_device.h> |
15 | #include <linux/err.h> |
16 | #include <linux/io.h> |
17 | |
18 | #include <linux/mtd/mtd.h> |
19 | #include <linux/mtd/map.h> |
20 | #include <linux/mtd/partitions.h> |
21 | #include <linux/mtd/concat.h> |
22 | |
23 | #include <mach/hardware.h> |
24 | #include <linux/sizes.h> |
25 | #include <asm/mach/flash.h> |
26 | |
27 | struct sa_subdev_info { |
28 | char name[16]; |
29 | struct map_info map; |
30 | struct mtd_info *mtd; |
31 | struct flash_platform_data *plat; |
32 | }; |
33 | |
34 | struct sa_info { |
35 | struct mtd_info *mtd; |
36 | int num_subdev; |
37 | struct sa_subdev_info subdev[]; |
38 | }; |
39 | |
40 | static DEFINE_SPINLOCK(sa1100_vpp_lock); |
41 | static int sa1100_vpp_refcnt; |
42 | static void sa1100_set_vpp(struct map_info *map, int on) |
43 | { |
44 | struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map); |
45 | unsigned long flags; |
46 | |
47 | spin_lock_irqsave(&sa1100_vpp_lock, flags); |
48 | if (on) { |
49 | if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */ |
50 | subdev->plat->set_vpp(1); |
51 | } else { |
52 | if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */ |
53 | subdev->plat->set_vpp(0); |
54 | } |
55 | spin_unlock_irqrestore(lock: &sa1100_vpp_lock, flags); |
56 | } |
57 | |
58 | static void sa1100_destroy_subdev(struct sa_subdev_info *subdev) |
59 | { |
60 | if (subdev->mtd) |
61 | map_destroy(mtd: subdev->mtd); |
62 | if (subdev->map.virt) |
63 | iounmap(addr: subdev->map.virt); |
64 | release_mem_region(subdev->map.phys, subdev->map.size); |
65 | } |
66 | |
67 | static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res) |
68 | { |
69 | unsigned long phys; |
70 | unsigned int size; |
71 | int ret; |
72 | |
73 | phys = res->start; |
74 | size = res->end - phys + 1; |
75 | |
76 | /* |
77 | * Retrieve the bankwidth from the MSC registers. |
78 | * We currently only implement CS0 and CS1 here. |
79 | */ |
80 | switch (phys) { |
81 | default: |
82 | printk(KERN_WARNING "SA1100 flash: unknown base address " |
83 | "0x%08lx, assuming CS0\n" , phys); |
84 | fallthrough; |
85 | case SA1100_CS0_PHYS: |
86 | subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4; |
87 | break; |
88 | |
89 | case SA1100_CS1_PHYS: |
90 | subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4; |
91 | break; |
92 | } |
93 | |
94 | if (!request_mem_region(phys, size, subdev->name)) { |
95 | ret = -EBUSY; |
96 | goto out; |
97 | } |
98 | |
99 | if (subdev->plat->set_vpp) |
100 | subdev->map.set_vpp = sa1100_set_vpp; |
101 | |
102 | subdev->map.phys = phys; |
103 | subdev->map.size = size; |
104 | subdev->map.virt = ioremap(offset: phys, size); |
105 | if (!subdev->map.virt) { |
106 | ret = -ENOMEM; |
107 | goto err; |
108 | } |
109 | |
110 | simple_map_init(&subdev->map); |
111 | |
112 | /* |
113 | * Now let's probe for the actual flash. Do it here since |
114 | * specific machine settings might have been set above. |
115 | */ |
116 | subdev->mtd = do_map_probe(name: subdev->plat->map_name, map: &subdev->map); |
117 | if (subdev->mtd == NULL) { |
118 | ret = -ENXIO; |
119 | goto err; |
120 | } |
121 | |
122 | printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n" , |
123 | phys, (unsigned)(subdev->mtd->size >> 20), |
124 | subdev->map.bankwidth * 8); |
125 | |
126 | return 0; |
127 | |
128 | err: |
129 | sa1100_destroy_subdev(subdev); |
130 | out: |
131 | return ret; |
132 | } |
133 | |
134 | static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat) |
135 | { |
136 | int i; |
137 | |
138 | if (info->mtd) { |
139 | mtd_device_unregister(master: info->mtd); |
140 | if (info->mtd != info->subdev[0].mtd) |
141 | mtd_concat_destroy(mtd: info->mtd); |
142 | } |
143 | |
144 | for (i = info->num_subdev - 1; i >= 0; i--) |
145 | sa1100_destroy_subdev(subdev: &info->subdev[i]); |
146 | kfree(objp: info); |
147 | |
148 | if (plat->exit) |
149 | plat->exit(); |
150 | } |
151 | |
152 | static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev, |
153 | struct flash_platform_data *plat) |
154 | { |
155 | struct sa_info *info; |
156 | int nr, size, i, ret = 0; |
157 | |
158 | /* |
159 | * Count number of devices. |
160 | */ |
161 | for (nr = 0; ; nr++) |
162 | if (!platform_get_resource(pdev, IORESOURCE_MEM, nr)) |
163 | break; |
164 | |
165 | if (nr == 0) { |
166 | ret = -ENODEV; |
167 | goto out; |
168 | } |
169 | |
170 | size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr; |
171 | |
172 | /* |
173 | * Allocate the map_info structs in one go. |
174 | */ |
175 | info = kzalloc(size, GFP_KERNEL); |
176 | if (!info) { |
177 | ret = -ENOMEM; |
178 | goto out; |
179 | } |
180 | |
181 | if (plat->init) { |
182 | ret = plat->init(); |
183 | if (ret) |
184 | goto err; |
185 | } |
186 | |
187 | /* |
188 | * Claim and then map the memory regions. |
189 | */ |
190 | for (i = 0; i < nr; i++) { |
191 | struct sa_subdev_info *subdev = &info->subdev[i]; |
192 | struct resource *res; |
193 | |
194 | res = platform_get_resource(pdev, IORESOURCE_MEM, i); |
195 | if (!res) |
196 | break; |
197 | |
198 | subdev->map.name = subdev->name; |
199 | sprintf(buf: subdev->name, fmt: "%s-%d" , plat->name, i); |
200 | subdev->plat = plat; |
201 | |
202 | ret = sa1100_probe_subdev(subdev, res); |
203 | if (ret) |
204 | break; |
205 | } |
206 | |
207 | info->num_subdev = i; |
208 | |
209 | /* |
210 | * ENXIO is special. It means we didn't find a chip when we probed. |
211 | */ |
212 | if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0)) |
213 | goto err; |
214 | |
215 | /* |
216 | * If we found one device, don't bother with concat support. If |
217 | * we found multiple devices, use concat if we have it available, |
218 | * otherwise fail. Either way, it'll be called "sa1100". |
219 | */ |
220 | if (info->num_subdev == 1) { |
221 | strcpy(info->subdev[0].name, plat->name); |
222 | info->mtd = info->subdev[0].mtd; |
223 | ret = 0; |
224 | } else if (info->num_subdev > 1) { |
225 | struct mtd_info **cdev; |
226 | |
227 | cdev = kmalloc_array(n: nr, size: sizeof(*cdev), GFP_KERNEL); |
228 | if (!cdev) { |
229 | ret = -ENOMEM; |
230 | goto err; |
231 | } |
232 | |
233 | /* |
234 | * We detected multiple devices. Concatenate them together. |
235 | */ |
236 | for (i = 0; i < info->num_subdev; i++) |
237 | cdev[i] = info->subdev[i].mtd; |
238 | |
239 | info->mtd = mtd_concat_create(subdev: cdev, num_devs: info->num_subdev, |
240 | name: plat->name); |
241 | kfree(objp: cdev); |
242 | if (info->mtd == NULL) { |
243 | ret = -ENXIO; |
244 | goto err; |
245 | } |
246 | } |
247 | info->mtd->dev.parent = &pdev->dev; |
248 | |
249 | if (ret == 0) |
250 | return info; |
251 | |
252 | err: |
253 | sa1100_destroy(info, plat); |
254 | out: |
255 | return ERR_PTR(error: ret); |
256 | } |
257 | |
258 | static const char * const part_probes[] = { "cmdlinepart" , "RedBoot" , NULL }; |
259 | |
260 | static int sa1100_mtd_probe(struct platform_device *pdev) |
261 | { |
262 | struct flash_platform_data *plat = dev_get_platdata(dev: &pdev->dev); |
263 | struct sa_info *info; |
264 | int err; |
265 | |
266 | if (!plat) |
267 | return -ENODEV; |
268 | |
269 | info = sa1100_setup_mtd(pdev, plat); |
270 | if (IS_ERR(ptr: info)) { |
271 | err = PTR_ERR(ptr: info); |
272 | goto out; |
273 | } |
274 | |
275 | /* |
276 | * Partition selection stuff. |
277 | */ |
278 | mtd_device_parse_register(mtd: info->mtd, part_probe_types: part_probes, NULL, defparts: plat->parts, |
279 | defnr_parts: plat->nr_parts); |
280 | |
281 | platform_set_drvdata(pdev, data: info); |
282 | err = 0; |
283 | |
284 | out: |
285 | return err; |
286 | } |
287 | |
288 | static void sa1100_mtd_remove(struct platform_device *pdev) |
289 | { |
290 | struct sa_info *info = platform_get_drvdata(pdev); |
291 | struct flash_platform_data *plat = dev_get_platdata(dev: &pdev->dev); |
292 | |
293 | sa1100_destroy(info, plat); |
294 | } |
295 | |
296 | static struct platform_driver sa1100_mtd_driver = { |
297 | .probe = sa1100_mtd_probe, |
298 | .remove_new = sa1100_mtd_remove, |
299 | .driver = { |
300 | .name = "sa1100-mtd" , |
301 | }, |
302 | }; |
303 | |
304 | module_platform_driver(sa1100_mtd_driver); |
305 | |
306 | MODULE_AUTHOR("Nicolas Pitre" ); |
307 | MODULE_DESCRIPTION("SA1100 CFI map driver" ); |
308 | MODULE_LICENSE("GPL" ); |
309 | MODULE_ALIAS("platform:sa1100-mtd" ); |
310 | |