Create platform_device.h to contain all the platform device details.
[safe/jmp/linux-2.6] / drivers / firmware / dell_rbu.c
1 /*
2  * dell_rbu.c
3  * Bios Update driver for Dell systems
4  * Author: Dell Inc
5  *         Abhay Salunke <abhay_salunke@dell.com>
6  *
7  * Copyright (C) 2005 Dell Inc.
8  *
9  * Remote BIOS Update (rbu) driver is used for updating DELL BIOS by
10  * creating entries in the /sys file systems on Linux 2.6 and higher
11  * kernels. The driver supports two mechanism to update the BIOS namely
12  * contiguous and packetized. Both these methods still require having some
13  * application to set the CMOS bit indicating the BIOS to update itself
14  * after a reboot.
15  *
16  * Contiguous method:
17  * This driver writes the incoming data in a monolithic image by allocating
18  * contiguous physical pages large enough to accommodate the incoming BIOS
19  * image size.
20  *
21  * Packetized method:
22  * The driver writes the incoming packet image by allocating a new packet
23  * on every time the packet data is written. This driver requires an
24  * application to break the BIOS image in to fixed sized packet chunks.
25  *
26  * See Documentation/dell_rbu.txt for more info.
27  *
28  * This program is free software; you can redistribute it and/or modify
29  * it under the terms of the GNU General Public License v2.0 as published by
30  * the Free Software Foundation
31  *
32  * This program is distributed in the hope that it will be useful,
33  * but WITHOUT ANY WARRANTY; without even the implied warranty of
34  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
35  * GNU General Public License for more details.
36  */
37 #include <linux/version.h>
38 #include <linux/config.h>
39 #include <linux/init.h>
40 #include <linux/module.h>
41 #include <linux/string.h>
42 #include <linux/errno.h>
43 #include <linux/blkdev.h>
44 #include <linux/platform_device.h>
45 #include <linux/spinlock.h>
46 #include <linux/moduleparam.h>
47 #include <linux/firmware.h>
48 #include <linux/dma-mapping.h>
49
50 MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>");
51 MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems");
52 MODULE_LICENSE("GPL");
53 MODULE_VERSION("3.0");
54
55 #define BIOS_SCAN_LIMIT 0xffffffff
56 #define MAX_IMAGE_LENGTH 16
57 static struct _rbu_data {
58         void *image_update_buffer;
59         unsigned long image_update_buffer_size;
60         unsigned long bios_image_size;
61         int image_update_ordernum;
62         int dma_alloc;
63         spinlock_t lock;
64         unsigned long packet_read_count;
65         unsigned long num_packets;
66         unsigned long packetsize;
67         unsigned long imagesize;
68         int entry_created;
69 } rbu_data;
70
71 static char image_type[MAX_IMAGE_LENGTH + 1] = "mono";
72 module_param_string(image_type, image_type, sizeof (image_type), 0);
73 MODULE_PARM_DESC(image_type,
74         "BIOS image type. choose- mono or packet or init");
75
76 struct packet_data {
77         struct list_head list;
78         size_t length;
79         void *data;
80         int ordernum;
81 };
82
83 static struct packet_data packet_data_head;
84
85 static struct platform_device *rbu_device;
86 static int context;
87 static dma_addr_t dell_rbu_dmaaddr;
88
89 static void init_packet_head(void)
90 {
91         INIT_LIST_HEAD(&packet_data_head.list);
92         rbu_data.packet_read_count = 0;
93         rbu_data.num_packets = 0;
94         rbu_data.packetsize = 0;
95         rbu_data.imagesize = 0;
96 }
97
98 static int create_packet(void *data, size_t length)
99 {
100         struct packet_data *newpacket;
101         int ordernum = 0;
102
103         pr_debug("create_packet: entry \n");
104
105         if (!rbu_data.packetsize) {
106                 pr_debug("create_packet: packetsize not specified\n");
107                 return -EINVAL;
108         }
109         spin_unlock(&rbu_data.lock);
110         newpacket = kmalloc(sizeof (struct packet_data), GFP_KERNEL);
111         spin_lock(&rbu_data.lock);
112
113         if (!newpacket) {
114                 printk(KERN_WARNING
115                         "dell_rbu:%s: failed to allocate new "
116                         "packet\n", __FUNCTION__);
117                 return -ENOMEM;
118         }
119
120         ordernum = get_order(length);
121         /*
122          * there is no upper limit on memory
123          * address for packetized mechanism
124          */
125         spin_unlock(&rbu_data.lock);
126         newpacket->data = (unsigned char *) __get_free_pages(GFP_KERNEL,
127                 ordernum);
128         spin_lock(&rbu_data.lock);
129
130         pr_debug("create_packet: newpacket %p\n", newpacket->data);
131
132         if (!newpacket->data) {
133                 printk(KERN_WARNING
134                         "dell_rbu:%s: failed to allocate new "
135                         "packet\n", __FUNCTION__);
136                 kfree(newpacket);
137                 return -ENOMEM;
138         }
139
140         newpacket->ordernum = ordernum;
141         ++rbu_data.num_packets;
142         /*
143          * initialize the newly created packet headers
144          */
145         INIT_LIST_HEAD(&newpacket->list);
146         list_add_tail(&newpacket->list, &packet_data_head.list);
147         /*
148          * packets may not have fixed size
149          */
150         newpacket->length = length;
151
152         memcpy(newpacket->data, data, length);
153
154         pr_debug("create_packet: exit \n");
155
156         return 0;
157 }
158
159 static int packetize_data(void *data, size_t length)
160 {
161         int rc = 0;
162         int done = 0;
163         int packet_length;
164         u8 *temp;
165         u8 *end = (u8 *) data + length;
166         pr_debug("packetize_data: data length %d\n", length);
167         if (!rbu_data.packetsize) {
168                 printk(KERN_WARNING
169                         "dell_rbu: packetsize not specified\n");
170                 return -EIO;
171         }
172
173         temp = (u8 *) data;
174
175         /* packetize the hunk */
176         while (!done) {
177                 if ((temp + rbu_data.packetsize) < end)
178                         packet_length = rbu_data.packetsize;
179                 else {
180                         /* this is the last packet */
181                         packet_length = end - temp;
182                         done = 1;
183                 }
184
185                 if ((rc = create_packet(temp, packet_length)))
186                         return rc;
187
188                 pr_debug("%lu:%lu\n", temp, (end - temp));
189                 temp += packet_length;
190         }
191
192         rbu_data.imagesize = length;
193
194         return rc;
195 }
196
197 static int do_packet_read(char *data, struct list_head *ptemp_list,
198         int length, int bytes_read, int *list_read_count)
199 {
200         void *ptemp_buf;
201         struct packet_data *newpacket = NULL;
202         int bytes_copied = 0;
203         int j = 0;
204
205         newpacket = list_entry(ptemp_list, struct packet_data, list);
206         *list_read_count += newpacket->length;
207
208         if (*list_read_count > bytes_read) {
209                 /* point to the start of unread data */
210                 j = newpacket->length - (*list_read_count - bytes_read);
211                 /* point to the offset in the packet buffer */
212                 ptemp_buf = (u8 *) newpacket->data + j;
213                 /*
214                  * check if there is enough room in
215                  * * the incoming buffer
216                  */
217                 if (length > (*list_read_count - bytes_read))
218                         /*
219                          * copy what ever is there in this
220                          * packet and move on
221                          */
222                         bytes_copied = (*list_read_count - bytes_read);
223                 else
224                         /* copy the remaining */
225                         bytes_copied = length;
226                 memcpy(data, ptemp_buf, bytes_copied);
227         }
228         return bytes_copied;
229 }
230
231 static int packet_read_list(char *data, size_t * pread_length)
232 {
233         struct list_head *ptemp_list;
234         int temp_count = 0;
235         int bytes_copied = 0;
236         int bytes_read = 0;
237         int remaining_bytes = 0;
238         char *pdest = data;
239
240         /* check if we have any packets */
241         if (0 == rbu_data.num_packets)
242                 return -ENOMEM;
243
244         remaining_bytes = *pread_length;
245         bytes_read = rbu_data.packet_read_count;
246
247         ptemp_list = (&packet_data_head.list)->next;
248         while (!list_empty(ptemp_list)) {
249                 bytes_copied = do_packet_read(pdest, ptemp_list,
250                         remaining_bytes, bytes_read, &temp_count);
251                 remaining_bytes -= bytes_copied;
252                 bytes_read += bytes_copied;
253                 pdest += bytes_copied;
254                 /*
255                  * check if we reached end of buffer before reaching the
256                  * last packet
257                  */
258                 if (remaining_bytes == 0)
259                         break;
260
261                 ptemp_list = ptemp_list->next;
262         }
263         /*finally set the bytes read */
264         *pread_length = bytes_read - rbu_data.packet_read_count;
265         rbu_data.packet_read_count = bytes_read;
266         return 0;
267 }
268
269 static void packet_empty_list(void)
270 {
271         struct list_head *ptemp_list;
272         struct list_head *pnext_list;
273         struct packet_data *newpacket;
274
275         ptemp_list = (&packet_data_head.list)->next;
276         while (!list_empty(ptemp_list)) {
277                 newpacket =
278                         list_entry(ptemp_list, struct packet_data, list);
279                 pnext_list = ptemp_list->next;
280                 list_del(ptemp_list);
281                 ptemp_list = pnext_list;
282                 /*
283                  * zero out the RBU packet memory before freeing
284                  * to make sure there are no stale RBU packets left in memory
285                  */
286                 memset(newpacket->data, 0, rbu_data.packetsize);
287                 free_pages((unsigned long) newpacket->data,
288                         newpacket->ordernum);
289                 kfree(newpacket);
290         }
291         rbu_data.packet_read_count = 0;
292         rbu_data.num_packets = 0;
293         rbu_data.imagesize = 0;
294 }
295
296 /*
297  * img_update_free: Frees the buffer allocated for storing BIOS image
298  * Always called with lock held and returned with lock held
299  */
300 static void img_update_free(void)
301 {
302         if (!rbu_data.image_update_buffer)
303                 return;
304         /*
305          * zero out this buffer before freeing it to get rid of any stale
306          * BIOS image copied in memory.
307          */
308         memset(rbu_data.image_update_buffer, 0,
309                 rbu_data.image_update_buffer_size);
310         if (rbu_data.dma_alloc == 1)
311                 dma_free_coherent(NULL, rbu_data.bios_image_size,
312                         rbu_data.image_update_buffer, dell_rbu_dmaaddr);
313         else
314                 free_pages((unsigned long) rbu_data.image_update_buffer,
315                         rbu_data.image_update_ordernum);
316
317         /*
318          * Re-initialize the rbu_data variables after a free
319          */
320         rbu_data.image_update_ordernum = -1;
321         rbu_data.image_update_buffer = NULL;
322         rbu_data.image_update_buffer_size = 0;
323         rbu_data.bios_image_size = 0;
324         rbu_data.dma_alloc = 0;
325 }
326
327 /*
328  * img_update_realloc: This function allocates the contiguous pages to
329  * accommodate the requested size of data. The memory address and size
330  * values are stored globally and on every call to this function the new
331  * size is checked to see if more data is required than the existing size.
332  * If true the previous memory is freed and new allocation is done to
333  * accommodate the new size. If the incoming size is less then than the
334  * already allocated size, then that memory is reused. This function is
335  * called with lock held and returns with lock held.
336  */
337 static int img_update_realloc(unsigned long size)
338 {
339         unsigned char *image_update_buffer = NULL;
340         unsigned long rc;
341         unsigned long img_buf_phys_addr;
342         int ordernum;
343         int dma_alloc = 0;
344
345         /*
346          * check if the buffer of sufficient size has been
347          * already allocated
348          */
349         if (rbu_data.image_update_buffer_size >= size) {
350                 /*
351                  * check for corruption
352                  */
353                 if ((size != 0) && (rbu_data.image_update_buffer == NULL)) {
354                         printk(KERN_ERR "dell_rbu:%s: corruption "
355                                 "check failed\n", __FUNCTION__);
356                         return -EINVAL;
357                 }
358                 /*
359                  * we have a valid pre-allocated buffer with
360                  * sufficient size
361                  */
362                 return 0;
363         }
364
365         /*
366          * free any previously allocated buffer
367          */
368         img_update_free();
369
370         spin_unlock(&rbu_data.lock);
371
372         ordernum = get_order(size);
373         image_update_buffer =
374                 (unsigned char *) __get_free_pages(GFP_KERNEL, ordernum);
375
376         img_buf_phys_addr =
377                 (unsigned long) virt_to_phys(image_update_buffer);
378
379         if (img_buf_phys_addr > BIOS_SCAN_LIMIT) {
380                 free_pages((unsigned long) image_update_buffer, ordernum);
381                 ordernum = -1;
382                 image_update_buffer = dma_alloc_coherent(NULL, size,
383                         &dell_rbu_dmaaddr, GFP_KERNEL);
384                 dma_alloc = 1;
385         }
386
387         spin_lock(&rbu_data.lock);
388
389         if (image_update_buffer != NULL) {
390                 rbu_data.image_update_buffer = image_update_buffer;
391                 rbu_data.image_update_buffer_size = size;
392                 rbu_data.bios_image_size =
393                         rbu_data.image_update_buffer_size;
394                 rbu_data.image_update_ordernum = ordernum;
395                 rbu_data.dma_alloc = dma_alloc;
396                 rc = 0;
397         } else {
398                 pr_debug("Not enough memory for image update:"
399                         "size = %ld\n", size);
400                 rc = -ENOMEM;
401         }
402
403         return rc;
404 }
405
406 static ssize_t read_packet_data(char *buffer, loff_t pos, size_t count)
407 {
408         int retval;
409         size_t bytes_left;
410         size_t data_length;
411         char *ptempBuf = buffer;
412
413         /* check to see if we have something to return */
414         if (rbu_data.num_packets == 0) {
415                 pr_debug("read_packet_data: no packets written\n");
416                 retval = -ENOMEM;
417                 goto read_rbu_data_exit;
418         }
419
420         if (pos > rbu_data.imagesize) {
421                 retval = 0;
422                 printk(KERN_WARNING "dell_rbu:read_packet_data: "
423                         "data underrun\n");
424                 goto read_rbu_data_exit;
425         }
426
427         bytes_left = rbu_data.imagesize - pos;
428         data_length = min(bytes_left, count);
429
430         if ((retval = packet_read_list(ptempBuf, &data_length)) < 0)
431                 goto read_rbu_data_exit;
432
433         if ((pos + count) > rbu_data.imagesize) {
434                 rbu_data.packet_read_count = 0;
435                 /* this was the last copy */
436                 retval = bytes_left;
437         } else
438                 retval = count;
439
440       read_rbu_data_exit:
441         return retval;
442 }
443
444 static ssize_t read_rbu_mono_data(char *buffer, loff_t pos, size_t count)
445 {
446         unsigned char *ptemp = NULL;
447         size_t bytes_left = 0;
448         size_t data_length = 0;
449         ssize_t ret_count = 0;
450
451         /* check to see if we have something to return */
452         if ((rbu_data.image_update_buffer == NULL) ||
453                 (rbu_data.bios_image_size == 0)) {
454                 pr_debug("read_rbu_data_mono: image_update_buffer %p ,"
455                         "bios_image_size %lu\n",
456                         rbu_data.image_update_buffer,
457                         rbu_data.bios_image_size);
458                 ret_count = -ENOMEM;
459                 goto read_rbu_data_exit;
460         }
461
462         if (pos > rbu_data.bios_image_size) {
463                 ret_count = 0;
464                 goto read_rbu_data_exit;
465         }
466
467         bytes_left = rbu_data.bios_image_size - pos;
468         data_length = min(bytes_left, count);
469
470         ptemp = rbu_data.image_update_buffer;
471         memcpy(buffer, (ptemp + pos), data_length);
472
473         if ((pos + count) > rbu_data.bios_image_size)
474                 /* this was the last copy */
475                 ret_count = bytes_left;
476         else
477                 ret_count = count;
478       read_rbu_data_exit:
479         return ret_count;
480 }
481
482 static ssize_t read_rbu_data(struct kobject *kobj, char *buffer,
483         loff_t pos, size_t count)
484 {
485         ssize_t ret_count = 0;
486
487         spin_lock(&rbu_data.lock);
488
489         if (!strcmp(image_type, "mono"))
490                 ret_count = read_rbu_mono_data(buffer, pos, count);
491         else if (!strcmp(image_type, "packet"))
492                 ret_count = read_packet_data(buffer, pos, count);
493         else
494                 pr_debug("read_rbu_data: invalid image type specified\n");
495
496         spin_unlock(&rbu_data.lock);
497         return ret_count;
498 }
499
500 static void callbackfn_rbu(const struct firmware *fw, void *context)
501 {
502         int rc = 0;
503
504         if (!fw || !fw->size) {
505                 rbu_data.entry_created = 0;
506                 return;
507         }
508
509         spin_lock(&rbu_data.lock);
510         if (!strcmp(image_type, "mono")) {
511                 if (!img_update_realloc(fw->size))
512                         memcpy(rbu_data.image_update_buffer,
513                                 fw->data, fw->size);
514         } else if (!strcmp(image_type, "packet")) {
515                 /*
516                  * we need to free previous packets if a
517                  * new hunk of packets needs to be downloaded
518                  */
519                 packet_empty_list();
520                 if (packetize_data(fw->data, fw->size))
521                         /* Incase something goes wrong when we are
522                          * in middle of packetizing the data, we
523                          * need to free up whatever packets might
524                          * have been created before we quit.
525                          */
526                         packet_empty_list();
527         } else
528                 pr_debug("invalid image type specified.\n");
529         spin_unlock(&rbu_data.lock);
530
531         rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG,
532                 "dell_rbu", &rbu_device->dev, &context, callbackfn_rbu);
533         if (rc)
534                 printk(KERN_ERR
535                         "dell_rbu:%s request_firmware_nowait failed"
536                         " %d\n", __FUNCTION__, rc);
537         else
538                 rbu_data.entry_created = 1;
539 }
540
541 static ssize_t read_rbu_image_type(struct kobject *kobj, char *buffer,
542         loff_t pos, size_t count)
543 {
544         int size = 0;
545         if (!pos)
546                 size = sprintf(buffer, "%s\n", image_type);
547         return size;
548 }
549
550 static ssize_t write_rbu_image_type(struct kobject *kobj, char *buffer,
551         loff_t pos, size_t count)
552 {
553         int rc = count;
554         int req_firm_rc = 0;
555         int i;
556         spin_lock(&rbu_data.lock);
557         /*
558          * Find the first newline or space
559          */
560         for (i = 0; i < count; ++i)
561                 if (buffer[i] == '\n' || buffer[i] == ' ') {
562                         buffer[i] = '\0';
563                         break;
564                 }
565         if (i == count)
566                 buffer[count] = '\0';
567
568         if (strstr(buffer, "mono"))
569                 strcpy(image_type, "mono");
570         else if (strstr(buffer, "packet"))
571                 strcpy(image_type, "packet");
572         else if (strstr(buffer, "init")) {
573                 /*
574                  * If due to the user error the driver gets in a bad
575                  * state where even though it is loaded , the
576                  * /sys/class/firmware/dell_rbu entries are missing.
577                  * to cover this situation the user can recreate entries
578                  * by writing init to image_type.
579                  */
580                 if (!rbu_data.entry_created) {
581                         spin_unlock(&rbu_data.lock);
582                         req_firm_rc = request_firmware_nowait(THIS_MODULE,
583                                 FW_ACTION_NOHOTPLUG, "dell_rbu",
584                                 &rbu_device->dev, &context,
585                                 callbackfn_rbu);
586                         if (req_firm_rc) {
587                                 printk(KERN_ERR
588                                         "dell_rbu:%s request_firmware_nowait"
589                                         " failed %d\n", __FUNCTION__, rc);
590                                 rc = -EIO;
591                         } else
592                                 rbu_data.entry_created = 1;
593
594                         spin_lock(&rbu_data.lock);
595                 }
596         } else {
597                 printk(KERN_WARNING "dell_rbu: image_type is invalid\n");
598                 spin_unlock(&rbu_data.lock);
599                 return -EINVAL;
600         }
601
602         /* we must free all previous allocations */
603         packet_empty_list();
604         img_update_free();
605         spin_unlock(&rbu_data.lock);
606
607         return rc;
608 }
609
610 static ssize_t read_rbu_packet_size(struct kobject *kobj, char *buffer,
611         loff_t pos, size_t count)
612 {
613         int size = 0;
614         if (!pos) {
615                 spin_lock(&rbu_data.lock);
616                 size = sprintf(buffer, "%lu\n", rbu_data.packetsize);
617                 spin_unlock(&rbu_data.lock);
618         }
619         return size;
620 }
621
622 static ssize_t write_rbu_packet_size(struct kobject *kobj, char *buffer,
623         loff_t pos, size_t count)
624 {
625         unsigned long temp;
626         spin_lock(&rbu_data.lock);
627         packet_empty_list();
628         sscanf(buffer, "%lu", &temp);
629         if (temp < 0xffffffff)
630                 rbu_data.packetsize = temp;
631
632         spin_unlock(&rbu_data.lock);
633         return count;
634 }
635
636 static struct bin_attribute rbu_data_attr = {
637         .attr = {.name = "data",.owner = THIS_MODULE,.mode = 0444},
638         .read = read_rbu_data,
639 };
640
641 static struct bin_attribute rbu_image_type_attr = {
642         .attr = {.name = "image_type",.owner = THIS_MODULE,.mode = 0644},
643         .read = read_rbu_image_type,
644         .write = write_rbu_image_type,
645 };
646
647 static struct bin_attribute rbu_packet_size_attr = {
648         .attr = {.name = "packet_size",.owner = THIS_MODULE,.mode = 0644},
649         .read = read_rbu_packet_size,
650         .write = write_rbu_packet_size,
651 };
652
653 static int __init dcdrbu_init(void)
654 {
655         int rc = 0;
656         spin_lock_init(&rbu_data.lock);
657
658         init_packet_head();
659         rbu_device =
660                 platform_device_register_simple("dell_rbu", -1, NULL, 0);
661         if (!rbu_device) {
662                 printk(KERN_ERR
663                         "dell_rbu:%s:platform_device_register_simple "
664                         "failed\n", __FUNCTION__);
665                 return -EIO;
666         }
667
668         sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_data_attr);
669         sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr);
670         sysfs_create_bin_file(&rbu_device->dev.kobj,
671                 &rbu_packet_size_attr);
672
673         rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG,
674                 "dell_rbu", &rbu_device->dev, &context, callbackfn_rbu);
675         if (rc)
676                 printk(KERN_ERR "dell_rbu:%s:request_firmware_nowait"
677                         " failed %d\n", __FUNCTION__, rc);
678         else
679                 rbu_data.entry_created = 1;
680
681         return rc;
682
683 }
684
685 static __exit void dcdrbu_exit(void)
686 {
687         spin_lock(&rbu_data.lock);
688         packet_empty_list();
689         img_update_free();
690         spin_unlock(&rbu_data.lock);
691         platform_device_unregister(rbu_device);
692 }
693
694 module_exit(dcdrbu_exit);
695 module_init(dcdrbu_init);