3 * Bios Update driver for Dell systems
5 * Abhay Salunke <abhay_salunke@dell.com>
7 * Copyright (C) 2005 Dell Inc.
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
17 * This driver writes the incoming data in a monolithic image by allocating
18 * contiguous physical pages large enough to accommodate the incoming BIOS
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.
26 * See Documentation/dell_rbu.txt for more info.
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
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.
37 #include <linux/init.h>
38 #include <linux/module.h>
39 #include <linux/string.h>
40 #include <linux/errno.h>
41 #include <linux/blkdev.h>
42 #include <linux/platform_device.h>
43 #include <linux/spinlock.h>
44 #include <linux/moduleparam.h>
45 #include <linux/firmware.h>
46 #include <linux/dma-mapping.h>
48 MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>");
49 MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems");
50 MODULE_LICENSE("GPL");
51 MODULE_VERSION("3.2");
53 #define BIOS_SCAN_LIMIT 0xffffffff
54 #define MAX_IMAGE_LENGTH 16
55 static struct _rbu_data {
56 void *image_update_buffer;
57 unsigned long image_update_buffer_size;
58 unsigned long bios_image_size;
59 int image_update_ordernum;
62 unsigned long packet_read_count;
63 unsigned long num_packets;
64 unsigned long packetsize;
65 unsigned long imagesize;
69 static char image_type[MAX_IMAGE_LENGTH + 1] = "mono";
70 module_param_string(image_type, image_type, sizeof (image_type), 0);
71 MODULE_PARM_DESC(image_type,
72 "BIOS image type. choose- mono or packet or init");
74 static unsigned long allocation_floor = 0x100000;
75 module_param(allocation_floor, ulong, 0644);
76 MODULE_PARM_DESC(allocation_floor,
77 "Minimum address for allocations when using Packet mode");
80 struct list_head list;
86 static struct packet_data packet_data_head;
88 static struct platform_device *rbu_device;
90 static dma_addr_t dell_rbu_dmaaddr;
92 static void init_packet_head(void)
94 INIT_LIST_HEAD(&packet_data_head.list);
95 rbu_data.packet_read_count = 0;
96 rbu_data.num_packets = 0;
97 rbu_data.packetsize = 0;
98 rbu_data.imagesize = 0;
101 static int create_packet(void *data, size_t length)
103 struct packet_data *newpacket;
106 unsigned int packet_array_size = 0;
107 void **invalid_addr_packet_array = NULL;
108 void *packet_data_temp_buf = NULL;
109 unsigned int idx = 0;
111 pr_debug("create_packet: entry \n");
113 if (!rbu_data.packetsize) {
114 pr_debug("create_packet: packetsize not specified\n");
119 spin_unlock(&rbu_data.lock);
121 newpacket = kzalloc(sizeof (struct packet_data), GFP_KERNEL);
125 "dell_rbu:%s: failed to allocate new "
126 "packet\n", __func__);
128 spin_lock(&rbu_data.lock);
132 ordernum = get_order(length);
135 * BIOS errata mean we cannot allocate packets below 1MB or they will
136 * be overwritten by BIOS.
138 * array to temporarily hold packets
139 * that are below the allocation floor
141 * NOTE: very simplistic because we only need the floor to be at 1MB
142 * due to BIOS errata. This shouldn't be used for higher floors
143 * or you will run out of mem trying to allocate the array.
145 packet_array_size = max(
146 (unsigned int)(allocation_floor / rbu_data.packetsize),
148 invalid_addr_packet_array = kzalloc(packet_array_size * sizeof(void*),
151 if (!invalid_addr_packet_array) {
153 "dell_rbu:%s: failed to allocate "
154 "invalid_addr_packet_array \n",
157 spin_lock(&rbu_data.lock);
158 goto out_alloc_packet;
161 while (!packet_data_temp_buf) {
162 packet_data_temp_buf = (unsigned char *)
163 __get_free_pages(GFP_KERNEL, ordernum);
164 if (!packet_data_temp_buf) {
166 "dell_rbu:%s: failed to allocate new "
167 "packet\n", __func__);
169 spin_lock(&rbu_data.lock);
170 goto out_alloc_packet_array;
173 if ((unsigned long)virt_to_phys(packet_data_temp_buf)
174 < allocation_floor) {
175 pr_debug("packet 0x%lx below floor at 0x%lx.\n",
176 (unsigned long)virt_to_phys(
177 packet_data_temp_buf),
179 invalid_addr_packet_array[idx++] = packet_data_temp_buf;
180 packet_data_temp_buf = NULL;
183 spin_lock(&rbu_data.lock);
185 newpacket->data = packet_data_temp_buf;
187 pr_debug("create_packet: newpacket at physical addr %lx\n",
188 (unsigned long)virt_to_phys(newpacket->data));
190 /* packets may not have fixed size */
191 newpacket->length = length;
192 newpacket->ordernum = ordernum;
193 ++rbu_data.num_packets;
195 /* initialize the newly created packet headers */
196 INIT_LIST_HEAD(&newpacket->list);
197 list_add_tail(&newpacket->list, &packet_data_head.list);
199 memcpy(newpacket->data, data, length);
201 pr_debug("create_packet: exit \n");
203 out_alloc_packet_array:
204 /* always free packet array */
206 pr_debug("freeing unused packet below floor 0x%lx.\n",
207 (unsigned long)virt_to_phys(
208 invalid_addr_packet_array[idx-1]));
209 free_pages((unsigned long)invalid_addr_packet_array[idx-1],
212 kfree(invalid_addr_packet_array);
215 /* if error, free data */
223 static int packetize_data(const u8 *data, size_t length)
229 u8 *end = (u8 *) data + length;
230 pr_debug("packetize_data: data length %zd\n", length);
231 if (!rbu_data.packetsize) {
233 "dell_rbu: packetsize not specified\n");
239 /* packetize the hunk */
241 if ((temp + rbu_data.packetsize) < end)
242 packet_length = rbu_data.packetsize;
244 /* this is the last packet */
245 packet_length = end - temp;
249 if ((rc = create_packet(temp, packet_length)))
252 pr_debug("%p:%td\n", temp, (end - temp));
253 temp += packet_length;
256 rbu_data.imagesize = length;
261 static int do_packet_read(char *data, struct list_head *ptemp_list,
262 int length, int bytes_read, int *list_read_count)
265 struct packet_data *newpacket = NULL;
266 int bytes_copied = 0;
269 newpacket = list_entry(ptemp_list, struct packet_data, list);
270 *list_read_count += newpacket->length;
272 if (*list_read_count > bytes_read) {
273 /* point to the start of unread data */
274 j = newpacket->length - (*list_read_count - bytes_read);
275 /* point to the offset in the packet buffer */
276 ptemp_buf = (u8 *) newpacket->data + j;
278 * check if there is enough room in
279 * * the incoming buffer
281 if (length > (*list_read_count - bytes_read))
283 * copy what ever is there in this
286 bytes_copied = (*list_read_count - bytes_read);
288 /* copy the remaining */
289 bytes_copied = length;
290 memcpy(data, ptemp_buf, bytes_copied);
295 static int packet_read_list(char *data, size_t * pread_length)
297 struct list_head *ptemp_list;
299 int bytes_copied = 0;
301 int remaining_bytes = 0;
304 /* check if we have any packets */
305 if (0 == rbu_data.num_packets)
308 remaining_bytes = *pread_length;
309 bytes_read = rbu_data.packet_read_count;
311 ptemp_list = (&packet_data_head.list)->next;
312 while (!list_empty(ptemp_list)) {
313 bytes_copied = do_packet_read(pdest, ptemp_list,
314 remaining_bytes, bytes_read, &temp_count);
315 remaining_bytes -= bytes_copied;
316 bytes_read += bytes_copied;
317 pdest += bytes_copied;
319 * check if we reached end of buffer before reaching the
322 if (remaining_bytes == 0)
325 ptemp_list = ptemp_list->next;
327 /*finally set the bytes read */
328 *pread_length = bytes_read - rbu_data.packet_read_count;
329 rbu_data.packet_read_count = bytes_read;
333 static void packet_empty_list(void)
335 struct list_head *ptemp_list;
336 struct list_head *pnext_list;
337 struct packet_data *newpacket;
339 ptemp_list = (&packet_data_head.list)->next;
340 while (!list_empty(ptemp_list)) {
342 list_entry(ptemp_list, struct packet_data, list);
343 pnext_list = ptemp_list->next;
344 list_del(ptemp_list);
345 ptemp_list = pnext_list;
347 * zero out the RBU packet memory before freeing
348 * to make sure there are no stale RBU packets left in memory
350 memset(newpacket->data, 0, rbu_data.packetsize);
351 free_pages((unsigned long) newpacket->data,
352 newpacket->ordernum);
355 rbu_data.packet_read_count = 0;
356 rbu_data.num_packets = 0;
357 rbu_data.imagesize = 0;
361 * img_update_free: Frees the buffer allocated for storing BIOS image
362 * Always called with lock held and returned with lock held
364 static void img_update_free(void)
366 if (!rbu_data.image_update_buffer)
369 * zero out this buffer before freeing it to get rid of any stale
370 * BIOS image copied in memory.
372 memset(rbu_data.image_update_buffer, 0,
373 rbu_data.image_update_buffer_size);
374 if (rbu_data.dma_alloc == 1)
375 dma_free_coherent(NULL, rbu_data.bios_image_size,
376 rbu_data.image_update_buffer, dell_rbu_dmaaddr);
378 free_pages((unsigned long) rbu_data.image_update_buffer,
379 rbu_data.image_update_ordernum);
382 * Re-initialize the rbu_data variables after a free
384 rbu_data.image_update_ordernum = -1;
385 rbu_data.image_update_buffer = NULL;
386 rbu_data.image_update_buffer_size = 0;
387 rbu_data.bios_image_size = 0;
388 rbu_data.dma_alloc = 0;
392 * img_update_realloc: This function allocates the contiguous pages to
393 * accommodate the requested size of data. The memory address and size
394 * values are stored globally and on every call to this function the new
395 * size is checked to see if more data is required than the existing size.
396 * If true the previous memory is freed and new allocation is done to
397 * accommodate the new size. If the incoming size is less then than the
398 * already allocated size, then that memory is reused. This function is
399 * called with lock held and returns with lock held.
401 static int img_update_realloc(unsigned long size)
403 unsigned char *image_update_buffer = NULL;
405 unsigned long img_buf_phys_addr;
410 * check if the buffer of sufficient size has been
413 if (rbu_data.image_update_buffer_size >= size) {
415 * check for corruption
417 if ((size != 0) && (rbu_data.image_update_buffer == NULL)) {
418 printk(KERN_ERR "dell_rbu:%s: corruption "
419 "check failed\n", __func__);
423 * we have a valid pre-allocated buffer with
430 * free any previously allocated buffer
434 spin_unlock(&rbu_data.lock);
436 ordernum = get_order(size);
437 image_update_buffer =
438 (unsigned char *) __get_free_pages(GFP_KERNEL, ordernum);
441 (unsigned long) virt_to_phys(image_update_buffer);
443 if (img_buf_phys_addr > BIOS_SCAN_LIMIT) {
444 free_pages((unsigned long) image_update_buffer, ordernum);
446 image_update_buffer = dma_alloc_coherent(NULL, size,
447 &dell_rbu_dmaaddr, GFP_KERNEL);
451 spin_lock(&rbu_data.lock);
453 if (image_update_buffer != NULL) {
454 rbu_data.image_update_buffer = image_update_buffer;
455 rbu_data.image_update_buffer_size = size;
456 rbu_data.bios_image_size =
457 rbu_data.image_update_buffer_size;
458 rbu_data.image_update_ordernum = ordernum;
459 rbu_data.dma_alloc = dma_alloc;
462 pr_debug("Not enough memory for image update:"
463 "size = %ld\n", size);
470 static ssize_t read_packet_data(char *buffer, loff_t pos, size_t count)
475 char *ptempBuf = buffer;
477 /* check to see if we have something to return */
478 if (rbu_data.num_packets == 0) {
479 pr_debug("read_packet_data: no packets written\n");
481 goto read_rbu_data_exit;
484 if (pos > rbu_data.imagesize) {
486 printk(KERN_WARNING "dell_rbu:read_packet_data: "
488 goto read_rbu_data_exit;
491 bytes_left = rbu_data.imagesize - pos;
492 data_length = min(bytes_left, count);
494 if ((retval = packet_read_list(ptempBuf, &data_length)) < 0)
495 goto read_rbu_data_exit;
497 if ((pos + count) > rbu_data.imagesize) {
498 rbu_data.packet_read_count = 0;
499 /* this was the last copy */
508 static ssize_t read_rbu_mono_data(char *buffer, loff_t pos, size_t count)
510 unsigned char *ptemp = NULL;
511 size_t bytes_left = 0;
512 size_t data_length = 0;
513 ssize_t ret_count = 0;
515 /* check to see if we have something to return */
516 if ((rbu_data.image_update_buffer == NULL) ||
517 (rbu_data.bios_image_size == 0)) {
518 pr_debug("read_rbu_data_mono: image_update_buffer %p ,"
519 "bios_image_size %lu\n",
520 rbu_data.image_update_buffer,
521 rbu_data.bios_image_size);
523 goto read_rbu_data_exit;
526 if (pos > rbu_data.bios_image_size) {
528 goto read_rbu_data_exit;
531 bytes_left = rbu_data.bios_image_size - pos;
532 data_length = min(bytes_left, count);
534 ptemp = rbu_data.image_update_buffer;
535 memcpy(buffer, (ptemp + pos), data_length);
537 if ((pos + count) > rbu_data.bios_image_size)
538 /* this was the last copy */
539 ret_count = bytes_left;
546 static ssize_t read_rbu_data(struct kobject *kobj,
547 struct bin_attribute *bin_attr,
548 char *buffer, loff_t pos, size_t count)
550 ssize_t ret_count = 0;
552 spin_lock(&rbu_data.lock);
554 if (!strcmp(image_type, "mono"))
555 ret_count = read_rbu_mono_data(buffer, pos, count);
556 else if (!strcmp(image_type, "packet"))
557 ret_count = read_packet_data(buffer, pos, count);
559 pr_debug("read_rbu_data: invalid image type specified\n");
561 spin_unlock(&rbu_data.lock);
565 static void callbackfn_rbu(const struct firmware *fw, void *context)
567 rbu_data.entry_created = 0;
569 if (!fw || !fw->size)
572 spin_lock(&rbu_data.lock);
573 if (!strcmp(image_type, "mono")) {
574 if (!img_update_realloc(fw->size))
575 memcpy(rbu_data.image_update_buffer,
577 } else if (!strcmp(image_type, "packet")) {
579 * we need to free previous packets if a
580 * new hunk of packets needs to be downloaded
583 if (packetize_data(fw->data, fw->size))
584 /* Incase something goes wrong when we are
585 * in middle of packetizing the data, we
586 * need to free up whatever packets might
587 * have been created before we quit.
591 pr_debug("invalid image type specified.\n");
592 spin_unlock(&rbu_data.lock);
595 static ssize_t read_rbu_image_type(struct kobject *kobj,
596 struct bin_attribute *bin_attr,
597 char *buffer, loff_t pos, size_t count)
601 size = sprintf(buffer, "%s\n", image_type);
605 static ssize_t write_rbu_image_type(struct kobject *kobj,
606 struct bin_attribute *bin_attr,
607 char *buffer, loff_t pos, size_t count)
612 spin_lock(&rbu_data.lock);
614 * Find the first newline or space
616 for (i = 0; i < count; ++i)
617 if (buffer[i] == '\n' || buffer[i] == ' ') {
622 buffer[count] = '\0';
624 if (strstr(buffer, "mono"))
625 strcpy(image_type, "mono");
626 else if (strstr(buffer, "packet"))
627 strcpy(image_type, "packet");
628 else if (strstr(buffer, "init")) {
630 * If due to the user error the driver gets in a bad
631 * state where even though it is loaded , the
632 * /sys/class/firmware/dell_rbu entries are missing.
633 * to cover this situation the user can recreate entries
634 * by writing init to image_type.
636 if (!rbu_data.entry_created) {
637 spin_unlock(&rbu_data.lock);
638 req_firm_rc = request_firmware_nowait(THIS_MODULE,
639 FW_ACTION_NOHOTPLUG, "dell_rbu",
640 &rbu_device->dev, &context,
644 "dell_rbu:%s request_firmware_nowait"
645 " failed %d\n", __func__, rc);
648 rbu_data.entry_created = 1;
650 spin_lock(&rbu_data.lock);
653 printk(KERN_WARNING "dell_rbu: image_type is invalid\n");
654 spin_unlock(&rbu_data.lock);
658 /* we must free all previous allocations */
661 spin_unlock(&rbu_data.lock);
666 static ssize_t read_rbu_packet_size(struct kobject *kobj,
667 struct bin_attribute *bin_attr,
668 char *buffer, loff_t pos, size_t count)
672 spin_lock(&rbu_data.lock);
673 size = sprintf(buffer, "%lu\n", rbu_data.packetsize);
674 spin_unlock(&rbu_data.lock);
679 static ssize_t write_rbu_packet_size(struct kobject *kobj,
680 struct bin_attribute *bin_attr,
681 char *buffer, loff_t pos, size_t count)
684 spin_lock(&rbu_data.lock);
686 sscanf(buffer, "%lu", &temp);
687 if (temp < 0xffffffff)
688 rbu_data.packetsize = temp;
690 spin_unlock(&rbu_data.lock);
694 static struct bin_attribute rbu_data_attr = {
695 .attr = {.name = "data", .mode = 0444},
696 .read = read_rbu_data,
699 static struct bin_attribute rbu_image_type_attr = {
700 .attr = {.name = "image_type", .mode = 0644},
701 .read = read_rbu_image_type,
702 .write = write_rbu_image_type,
705 static struct bin_attribute rbu_packet_size_attr = {
706 .attr = {.name = "packet_size", .mode = 0644},
707 .read = read_rbu_packet_size,
708 .write = write_rbu_packet_size,
711 static int __init dcdrbu_init(void)
714 spin_lock_init(&rbu_data.lock);
717 rbu_device = platform_device_register_simple("dell_rbu", -1, NULL, 0);
718 if (IS_ERR(rbu_device)) {
720 "dell_rbu:%s:platform_device_register_simple "
721 "failed\n", __func__);
722 return PTR_ERR(rbu_device);
725 rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_data_attr);
728 rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr);
731 rc = sysfs_create_bin_file(&rbu_device->dev.kobj,
732 &rbu_packet_size_attr);
736 rbu_data.entry_created = 0;
740 sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr);
742 sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_data_attr);
744 platform_device_unregister(rbu_device);
748 static __exit void dcdrbu_exit(void)
750 spin_lock(&rbu_data.lock);
753 spin_unlock(&rbu_data.lock);
754 platform_device_unregister(rbu_device);
757 module_exit(dcdrbu_exit);
758 module_init(dcdrbu_init);
760 /* vim:noet:ts=8:sw=8