Commit | Line | Data |
---|---|---|
dbdf04c4 MS |
1 | /* |
2 | * (C) Copyright IBM Deutschland Entwicklung GmbH 2006 | |
3 | * | |
4 | * Author: Maxim Shchetynin <maxim@de.ibm.com> | |
5 | * | |
6 | * Axon DDR2 device driver. | |
7 | * It registers one block device per Axon's DDR2 memory bank found on a system. | |
8 | * Block devices are called axonram?, their major and minor numbers are | |
9 | * available in /proc/devices, /proc/partitions or in /sys/block/axonram?/dev. | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2, or (at your option) | |
14 | * any later version. | |
15 | * | |
16 | * This program is distributed in the hope that it will be useful, | |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | * GNU General Public License for more details. | |
20 | * | |
21 | * You should have received a copy of the GNU General Public License | |
22 | * along with this program; if not, write to the Free Software | |
23 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
24 | */ | |
25 | ||
26 | #include <linux/bio.h> | |
27 | #include <linux/blkdev.h> | |
28 | #include <linux/buffer_head.h> | |
29 | #include <linux/device.h> | |
30 | #include <linux/errno.h> | |
31 | #include <linux/fs.h> | |
32 | #include <linux/genhd.h> | |
33 | #include <linux/interrupt.h> | |
34 | #include <linux/io.h> | |
35 | #include <linux/ioport.h> | |
36 | #include <linux/irq.h> | |
37 | #include <linux/irqreturn.h> | |
38 | #include <linux/kernel.h> | |
39 | #include <linux/mm.h> | |
40 | #include <linux/mod_devicetable.h> | |
41 | #include <linux/module.h> | |
42 | #include <linux/slab.h> | |
43 | #include <linux/string.h> | |
44 | #include <linux/types.h> | |
45 | #include <asm/of_device.h> | |
46 | #include <asm/of_platform.h> | |
47 | #include <asm/page.h> | |
48 | #include <asm/prom.h> | |
49 | ||
50 | #define AXON_RAM_MODULE_NAME "axonram" | |
51 | #define AXON_RAM_DEVICE_NAME "axonram" | |
52 | #define AXON_RAM_MINORS_PER_DISK 16 | |
53 | #define AXON_RAM_BLOCK_SHIFT PAGE_SHIFT | |
54 | #define AXON_RAM_BLOCK_SIZE 1 << AXON_RAM_BLOCK_SHIFT | |
55 | #define AXON_RAM_SECTOR_SHIFT 9 | |
56 | #define AXON_RAM_SECTOR_SIZE 1 << AXON_RAM_SECTOR_SHIFT | |
57 | #define AXON_RAM_IRQ_FLAGS IRQF_SHARED | IRQF_TRIGGER_RISING | |
58 | ||
59 | struct axon_ram_bank { | |
60 | struct of_device *device; | |
61 | struct gendisk *disk; | |
62 | unsigned int irq_correctable; | |
63 | unsigned int irq_uncorrectable; | |
64 | unsigned long ph_addr; | |
65 | unsigned long io_addr; | |
66 | unsigned long size; | |
67 | unsigned long ecc_counter; | |
68 | }; | |
69 | ||
70 | static ssize_t | |
71 | axon_ram_sysfs_ecc(struct device *dev, struct device_attribute *attr, char *buf) | |
72 | { | |
73 | struct of_device *device = to_of_device(dev); | |
74 | struct axon_ram_bank *bank = device->dev.platform_data; | |
75 | ||
76 | BUG_ON(!bank); | |
77 | ||
78 | return sprintf(buf, "%ld\n", bank->ecc_counter); | |
79 | } | |
80 | ||
81 | static DEVICE_ATTR(ecc, S_IRUGO, axon_ram_sysfs_ecc, NULL); | |
82 | ||
83 | /** | |
84 | * axon_ram_irq_handler - interrupt handler for Axon RAM ECC | |
85 | * @irq: interrupt ID | |
86 | * @dev: pointer to of_device | |
87 | */ | |
88 | static irqreturn_t | |
89 | axon_ram_irq_handler(int irq, void *dev) | |
90 | { | |
91 | struct of_device *device = dev; | |
92 | struct axon_ram_bank *bank = device->dev.platform_data; | |
93 | ||
94 | BUG_ON(!bank); | |
95 | ||
96 | if (irq == bank->irq_correctable) { | |
97 | dev_err(&device->dev, "Correctable memory error occured\n"); | |
98 | bank->ecc_counter++; | |
99 | return IRQ_HANDLED; | |
100 | } else if (irq == bank->irq_uncorrectable) { | |
101 | dev_err(&device->dev, "Uncorrectable memory error occured\n"); | |
102 | panic("Critical ECC error on %s", device->node->full_name); | |
103 | } | |
104 | ||
105 | return IRQ_NONE; | |
106 | } | |
107 | ||
108 | /** | |
109 | * axon_ram_make_request - make_request() method for block device | |
110 | * @queue, @bio: see blk_queue_make_request() | |
111 | */ | |
112 | static int | |
113 | axon_ram_make_request(struct request_queue *queue, struct bio *bio) | |
114 | { | |
115 | struct axon_ram_bank *bank = bio->bi_bdev->bd_disk->private_data; | |
116 | unsigned long phys_mem, phys_end; | |
117 | void *user_mem; | |
118 | struct bio_vec *vec; | |
119 | unsigned int transfered; | |
120 | unsigned short idx; | |
121 | int rc = 0; | |
122 | ||
123 | phys_mem = bank->io_addr + (bio->bi_sector << AXON_RAM_SECTOR_SHIFT); | |
124 | phys_end = bank->io_addr + bank->size; | |
125 | transfered = 0; | |
126 | bio_for_each_segment(vec, bio, idx) { | |
127 | if (unlikely(phys_mem + vec->bv_len > phys_end)) { | |
128 | bio_io_error(bio, bio->bi_size); | |
129 | rc = -ERANGE; | |
130 | break; | |
131 | } | |
132 | ||
133 | user_mem = page_address(vec->bv_page) + vec->bv_offset; | |
134 | if (bio_data_dir(bio) == READ) | |
135 | memcpy(user_mem, (void *) phys_mem, vec->bv_len); | |
136 | else | |
137 | memcpy((void *) phys_mem, user_mem, vec->bv_len); | |
138 | ||
139 | phys_mem += vec->bv_len; | |
140 | transfered += vec->bv_len; | |
141 | } | |
142 | bio_endio(bio, transfered, 0); | |
143 | ||
144 | return rc; | |
145 | } | |
146 | ||
147 | /** | |
148 | * axon_ram_direct_access - direct_access() method for block device | |
149 | * @device, @sector, @data: see block_device_operations method | |
150 | */ | |
151 | static int | |
152 | axon_ram_direct_access(struct block_device *device, sector_t sector, | |
153 | unsigned long *data) | |
154 | { | |
155 | struct axon_ram_bank *bank = device->bd_disk->private_data; | |
156 | loff_t offset; | |
157 | ||
158 | offset = sector << AXON_RAM_SECTOR_SHIFT; | |
159 | if (offset >= bank->size) { | |
160 | dev_err(&bank->device->dev, "Access outside of address space\n"); | |
161 | return -ERANGE; | |
162 | } | |
163 | ||
164 | *data = bank->ph_addr + offset; | |
165 | ||
166 | return 0; | |
167 | } | |
168 | ||
169 | static struct block_device_operations axon_ram_devops = { | |
170 | .owner = THIS_MODULE, | |
171 | .direct_access = axon_ram_direct_access | |
172 | }; | |
173 | ||
174 | /** | |
175 | * axon_ram_probe - probe() method for platform driver | |
176 | * @device, @device_id: see of_platform_driver method | |
177 | */ | |
178 | static int | |
179 | axon_ram_probe(struct of_device *device, const struct of_device_id *device_id) | |
180 | { | |
181 | static int axon_ram_bank_id = -1; | |
182 | struct axon_ram_bank *bank; | |
183 | struct resource resource; | |
184 | int rc = 0; | |
185 | ||
186 | axon_ram_bank_id++; | |
187 | ||
188 | dev_info(&device->dev, "Found memory controller on %s\n", | |
189 | device->node->full_name); | |
190 | ||
191 | bank = kzalloc(sizeof(struct axon_ram_bank), GFP_KERNEL); | |
192 | if (bank == NULL) { | |
193 | dev_err(&device->dev, "Out of memory\n"); | |
194 | rc = -ENOMEM; | |
195 | goto failed; | |
196 | } | |
197 | ||
198 | device->dev.platform_data = bank; | |
199 | ||
200 | bank->device = device; | |
201 | ||
202 | if (of_address_to_resource(device->node, 0, &resource) != 0) { | |
203 | dev_err(&device->dev, "Cannot access device tree\n"); | |
204 | rc = -EFAULT; | |
205 | goto failed; | |
206 | } | |
207 | ||
208 | bank->size = resource.end - resource.start + 1; | |
209 | ||
210 | if (bank->size == 0) { | |
211 | dev_err(&device->dev, "No DDR2 memory found for %s%d\n", | |
212 | AXON_RAM_DEVICE_NAME, axon_ram_bank_id); | |
213 | rc = -ENODEV; | |
214 | goto failed; | |
215 | } | |
216 | ||
217 | dev_info(&device->dev, "Register DDR2 memory device %s%d with %luMB\n", | |
218 | AXON_RAM_DEVICE_NAME, axon_ram_bank_id, bank->size >> 20); | |
219 | ||
220 | bank->ph_addr = resource.start; | |
221 | bank->io_addr = (unsigned long) ioremap_flags( | |
222 | bank->ph_addr, bank->size, _PAGE_NO_CACHE); | |
223 | if (bank->io_addr == 0) { | |
224 | dev_err(&device->dev, "ioremap() failed\n"); | |
225 | rc = -EFAULT; | |
226 | goto failed; | |
227 | } | |
228 | ||
229 | bank->disk = alloc_disk(AXON_RAM_MINORS_PER_DISK); | |
230 | if (bank->disk == NULL) { | |
231 | dev_err(&device->dev, "Cannot register disk\n"); | |
232 | rc = -EFAULT; | |
233 | goto failed; | |
234 | } | |
235 | ||
236 | bank->disk->first_minor = 0; | |
237 | bank->disk->fops = &axon_ram_devops; | |
238 | bank->disk->private_data = bank; | |
239 | bank->disk->driverfs_dev = &device->dev; | |
240 | ||
241 | sprintf(bank->disk->disk_name, "%s%d", | |
242 | AXON_RAM_DEVICE_NAME, axon_ram_bank_id); | |
243 | bank->disk->major = register_blkdev(0, bank->disk->disk_name); | |
244 | if (bank->disk->major < 0) { | |
245 | dev_err(&device->dev, "Cannot register block device\n"); | |
246 | rc = -EFAULT; | |
247 | goto failed; | |
248 | } | |
249 | ||
250 | bank->disk->queue = blk_alloc_queue(GFP_KERNEL); | |
251 | if (bank->disk->queue == NULL) { | |
252 | dev_err(&device->dev, "Cannot register disk queue\n"); | |
253 | rc = -EFAULT; | |
254 | goto failed; | |
255 | } | |
256 | ||
257 | set_capacity(bank->disk, bank->size >> AXON_RAM_SECTOR_SHIFT); | |
258 | blk_queue_make_request(bank->disk->queue, axon_ram_make_request); | |
259 | blk_queue_hardsect_size(bank->disk->queue, AXON_RAM_SECTOR_SIZE); | |
260 | add_disk(bank->disk); | |
261 | ||
262 | bank->irq_correctable = irq_of_parse_and_map(device->node, 0); | |
263 | bank->irq_uncorrectable = irq_of_parse_and_map(device->node, 1); | |
264 | if ((bank->irq_correctable <= 0) || (bank->irq_uncorrectable <= 0)) { | |
265 | dev_err(&device->dev, "Cannot access ECC interrupt ID\n"); | |
266 | rc = -EFAULT; | |
267 | goto failed; | |
268 | } | |
269 | ||
270 | rc = request_irq(bank->irq_correctable, axon_ram_irq_handler, | |
271 | AXON_RAM_IRQ_FLAGS, bank->disk->disk_name, device); | |
272 | if (rc != 0) { | |
273 | dev_err(&device->dev, "Cannot register ECC interrupt handler\n"); | |
274 | bank->irq_correctable = bank->irq_uncorrectable = 0; | |
275 | rc = -EFAULT; | |
276 | goto failed; | |
277 | } | |
278 | ||
279 | rc = request_irq(bank->irq_uncorrectable, axon_ram_irq_handler, | |
280 | AXON_RAM_IRQ_FLAGS, bank->disk->disk_name, device); | |
281 | if (rc != 0) { | |
282 | dev_err(&device->dev, "Cannot register ECC interrupt handler\n"); | |
283 | bank->irq_uncorrectable = 0; | |
284 | rc = -EFAULT; | |
285 | goto failed; | |
286 | } | |
287 | ||
288 | rc = device_create_file(&device->dev, &dev_attr_ecc); | |
289 | if (rc != 0) { | |
290 | dev_err(&device->dev, "Cannot create sysfs file\n"); | |
291 | rc = -EFAULT; | |
292 | goto failed; | |
293 | } | |
294 | ||
295 | return 0; | |
296 | ||
297 | failed: | |
298 | if (bank != NULL) { | |
299 | if (bank->irq_uncorrectable > 0) | |
300 | free_irq(bank->irq_uncorrectable, device); | |
301 | if (bank->irq_correctable > 0) | |
302 | free_irq(bank->irq_correctable, device); | |
303 | if (bank->disk != NULL) { | |
304 | if (bank->disk->queue != NULL) | |
305 | blk_cleanup_queue(bank->disk->queue); | |
306 | if (bank->disk->major > 0) | |
307 | unregister_blkdev(bank->disk->major, | |
308 | bank->disk->disk_name); | |
309 | del_gendisk(bank->disk); | |
310 | } | |
311 | device->dev.platform_data = NULL; | |
312 | if (bank->io_addr != 0) | |
313 | iounmap((void __iomem *) bank->io_addr); | |
314 | kfree(bank); | |
315 | } | |
316 | ||
317 | return rc; | |
318 | } | |
319 | ||
320 | /** | |
321 | * axon_ram_remove - remove() method for platform driver | |
322 | * @device: see of_platform_driver method | |
323 | */ | |
324 | static int | |
325 | axon_ram_remove(struct of_device *device) | |
326 | { | |
327 | struct axon_ram_bank *bank = device->dev.platform_data; | |
328 | ||
329 | BUG_ON(!bank || !bank->disk); | |
330 | ||
331 | device_remove_file(&device->dev, &dev_attr_ecc); | |
332 | free_irq(bank->irq_uncorrectable, device); | |
333 | free_irq(bank->irq_correctable, device); | |
334 | blk_cleanup_queue(bank->disk->queue); | |
335 | unregister_blkdev(bank->disk->major, bank->disk->disk_name); | |
336 | del_gendisk(bank->disk); | |
337 | iounmap((void __iomem *) bank->io_addr); | |
338 | kfree(bank); | |
339 | ||
340 | return 0; | |
341 | } | |
342 | ||
343 | static struct of_device_id axon_ram_device_id[] = { | |
344 | { | |
345 | .type = "dma-memory" | |
346 | }, | |
347 | {} | |
348 | }; | |
349 | ||
350 | static struct of_platform_driver axon_ram_driver = { | |
351 | .owner = THIS_MODULE, | |
352 | .name = AXON_RAM_MODULE_NAME, | |
353 | .match_table = axon_ram_device_id, | |
354 | .probe = axon_ram_probe, | |
355 | .remove = axon_ram_remove | |
356 | }; | |
357 | ||
358 | /** | |
359 | * axon_ram_init | |
360 | */ | |
361 | static int __init | |
362 | axon_ram_init(void) | |
363 | { | |
364 | return of_register_platform_driver(&axon_ram_driver); | |
365 | } | |
366 | ||
367 | /** | |
368 | * axon_ram_exit | |
369 | */ | |
370 | static void __exit | |
371 | axon_ram_exit(void) | |
372 | { | |
373 | of_unregister_platform_driver(&axon_ram_driver); | |
374 | } | |
375 | ||
376 | module_init(axon_ram_init); | |
377 | module_exit(axon_ram_exit); | |
378 | ||
379 | MODULE_LICENSE("GPL"); | |
380 | MODULE_AUTHOR("Maxim Shchetynin <maxim@de.ibm.com>"); | |
381 | MODULE_DESCRIPTION("Axon DDR2 RAM device driver for IBM Cell BE"); |