| /* |
| * dell_rbu.c |
| * Bios Update driver for Dell systems |
| * Author: Dell Inc |
| * Abhay Salunke <abhay_salunke@dell.com> |
| * |
| * Copyright (C) 2005 Dell Inc. |
| * |
| * Remote BIOS Update (rbu) driver is used for updating DELL BIOS by |
| * creating entries in the /sys file systems on Linux 2.6 and higher |
| * kernels. The driver supports two mechanism to update the BIOS namely |
| * contiguous and packetized. Both these methods still require having some |
| * application to set the CMOS bit indicating the BIOS to update itself |
| * after a reboot. |
| * |
| * Contiguous method: |
| * This driver writes the incoming data in a monolithic image by allocating |
| * contiguous physical pages large enough to accommodate the incoming BIOS |
| * image size. |
| * |
| * Packetized method: |
| * The driver writes the incoming packet image by allocating a new packet |
| * on every time the packet data is written. This driver requires an |
| * application to break the BIOS image in to fixed sized packet chunks. |
| * |
| * See Documentation/dell_rbu.txt for more info. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License v2.0 as published by |
| * the Free Software Foundation |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/blkdev.h> |
| #include <linux/platform_device.h> |
| #include <linux/spinlock.h> |
| #include <linux/moduleparam.h> |
| #include <linux/firmware.h> |
| #include <linux/dma-mapping.h> |
| #include <asm/set_memory.h> |
| |
| MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>"); |
| MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems"); |
| MODULE_LICENSE("GPL"); |
| MODULE_VERSION("3.2"); |
| |
| #define BIOS_SCAN_LIMIT 0xffffffff |
| #define MAX_IMAGE_LENGTH 16 |
| static struct _rbu_data { |
| void *image_update_buffer; |
| unsigned long image_update_buffer_size; |
| unsigned long bios_image_size; |
| int image_update_ordernum; |
| spinlock_t lock; |
| unsigned long packet_read_count; |
| unsigned long num_packets; |
| unsigned long packetsize; |
| unsigned long imagesize; |
| int entry_created; |
| } rbu_data; |
| |
| static char image_type[MAX_IMAGE_LENGTH + 1] = "mono"; |
| module_param_string(image_type, image_type, sizeof (image_type), 0); |
| MODULE_PARM_DESC(image_type, |
| "BIOS image type. choose- mono or packet or init"); |
| |
| static unsigned long allocation_floor = 0x100000; |
| module_param(allocation_floor, ulong, 0644); |
| MODULE_PARM_DESC(allocation_floor, |
| "Minimum address for allocations when using Packet mode"); |
| |
| struct packet_data { |
| struct list_head list; |
| size_t length; |
| void *data; |
| int ordernum; |
| }; |
| |
| static struct packet_data packet_data_head; |
| |
| static struct platform_device *rbu_device; |
| static int context; |
| |
| static void init_packet_head(void) |
| { |
| INIT_LIST_HEAD(&packet_data_head.list); |
| rbu_data.packet_read_count = 0; |
| rbu_data.num_packets = 0; |
| rbu_data.packetsize = 0; |
| rbu_data.imagesize = 0; |
| } |
| |
| static int create_packet(void *data, size_t length) |
| { |
| struct packet_data *newpacket; |
| int ordernum = 0; |
| int retval = 0; |
| unsigned int packet_array_size = 0; |
| void **invalid_addr_packet_array = NULL; |
| void *packet_data_temp_buf = NULL; |
| unsigned int idx = 0; |
| |
| pr_debug("create_packet: entry \n"); |
| |
| if (!rbu_data.packetsize) { |
| pr_debug("create_packet: packetsize not specified\n"); |
| retval = -EINVAL; |
| goto out_noalloc; |
| } |
| |
| spin_unlock(&rbu_data.lock); |
| |
| newpacket = kzalloc(sizeof (struct packet_data), GFP_KERNEL); |
| |
| if (!newpacket) { |
| printk(KERN_WARNING |
| "dell_rbu:%s: failed to allocate new " |
| "packet\n", __func__); |
| retval = -ENOMEM; |
| spin_lock(&rbu_data.lock); |
| goto out_noalloc; |
| } |
| |
| ordernum = get_order(length); |
| |
| /* |
| * BIOS errata mean we cannot allocate packets below 1MB or they will |
| * be overwritten by BIOS. |
| * |
| * array to temporarily hold packets |
| * that are below the allocation floor |
| * |
| * NOTE: very simplistic because we only need the floor to be at 1MB |
| * due to BIOS errata. This shouldn't be used for higher floors |
| * or you will run out of mem trying to allocate the array. |
| */ |
| packet_array_size = max( |
| (unsigned int)(allocation_floor / rbu_data.packetsize), |
| (unsigned int)1); |
| invalid_addr_packet_array = kcalloc(packet_array_size, sizeof(void *), |
| GFP_KERNEL); |
| |
| if (!invalid_addr_packet_array) { |
| printk(KERN_WARNING |
| "dell_rbu:%s: failed to allocate " |
| "invalid_addr_packet_array \n", |
| __func__); |
| retval = -ENOMEM; |
| spin_lock(&rbu_data.lock); |
| goto out_alloc_packet; |
| } |
| |
| while (!packet_data_temp_buf) { |
| packet_data_temp_buf = (unsigned char *) |
| __get_free_pages(GFP_KERNEL, ordernum); |
| if (!packet_data_temp_buf) { |
| printk(KERN_WARNING |
| "dell_rbu:%s: failed to allocate new " |
| "packet\n", __func__); |
| retval = -ENOMEM; |
| spin_lock(&rbu_data.lock); |
| goto out_alloc_packet_array; |
| } |
| |
| if ((unsigned long)virt_to_phys(packet_data_temp_buf) |
| < allocation_floor) { |
| pr_debug("packet 0x%lx below floor at 0x%lx.\n", |
| (unsigned long)virt_to_phys( |
| packet_data_temp_buf), |
| allocation_floor); |
| invalid_addr_packet_array[idx++] = packet_data_temp_buf; |
| packet_data_temp_buf = NULL; |
| } |
| } |
| /* |
| * set to uncachable or it may never get written back before reboot |
| */ |
| set_memory_uc((unsigned long)packet_data_temp_buf, 1 << ordernum); |
| |
| spin_lock(&rbu_data.lock); |
| |
| newpacket->data = packet_data_temp_buf; |
| |
| pr_debug("create_packet: newpacket at physical addr %lx\n", |
| (unsigned long)virt_to_phys(newpacket->data)); |
| |
| /* packets may not have fixed size */ |
| newpacket->length = length; |
| newpacket->ordernum = ordernum; |
| ++rbu_data.num_packets; |
| |
| /* initialize the newly created packet headers */ |
| INIT_LIST_HEAD(&newpacket->list); |
| list_add_tail(&newpacket->list, &packet_data_head.list); |
| |
| memcpy(newpacket->data, data, length); |
| |
| pr_debug("create_packet: exit \n"); |
| |
| out_alloc_packet_array: |
| /* always free packet array */ |
| for (;idx>0;idx--) { |
| pr_debug("freeing unused packet below floor 0x%lx.\n", |
| (unsigned long)virt_to_phys( |
| invalid_addr_packet_array[idx-1])); |
| free_pages((unsigned long)invalid_addr_packet_array[idx-1], |
| ordernum); |
| } |
| kfree(invalid_addr_packet_array); |
| |
| out_alloc_packet: |
| /* if error, free data */ |
| if (retval) |
| kfree(newpacket); |
| |
| out_noalloc: |
| return retval; |
| } |
| |
| static int packetize_data(const u8 *data, size_t length) |
| { |
| int rc = 0; |
| int done = 0; |
| int packet_length; |
| u8 *temp; |
| u8 *end = (u8 *) data + length; |
| pr_debug("packetize_data: data length %zd\n", length); |
| if (!rbu_data.packetsize) { |
| printk(KERN_WARNING |
| "dell_rbu: packetsize not specified\n"); |
| return -EIO; |
| } |
| |
| temp = (u8 *) data; |
| |
| /* packetize the hunk */ |
| while (!done) { |
| if ((temp + rbu_data.packetsize) < end) |
| packet_length = rbu_data.packetsize; |
| else { |
| /* this is the last packet */ |
| packet_length = end - temp; |
| done = 1; |
| } |
| |
| if ((rc = create_packet(temp, packet_length))) |
| return rc; |
| |
| pr_debug("%p:%td\n", temp, (end - temp)); |
| temp += packet_length; |
| } |
| |
| rbu_data.imagesize = length; |
| |
| return rc; |
| } |
| |
| static int do_packet_read(char *data, struct list_head *ptemp_list, |
| int length, int bytes_read, int *list_read_count) |
| { |
| void *ptemp_buf; |
| struct packet_data *newpacket = NULL; |
| int bytes_copied = 0; |
| int j = 0; |
| |
| newpacket = list_entry(ptemp_list, struct packet_data, list); |
| *list_read_count += newpacket->length; |
| |
| if (*list_read_count > bytes_read) { |
| /* point to the start of unread data */ |
| j = newpacket->length - (*list_read_count - bytes_read); |
| /* point to the offset in the packet buffer */ |
| ptemp_buf = (u8 *) newpacket->data + j; |
| /* |
| * check if there is enough room in |
| * * the incoming buffer |
| */ |
| if (length > (*list_read_count - bytes_read)) |
| /* |
| * copy what ever is there in this |
| * packet and move on |
| */ |
| bytes_copied = (*list_read_count - bytes_read); |
| else |
| /* copy the remaining */ |
| bytes_copied = length; |
| memcpy(data, ptemp_buf, bytes_copied); |
| } |
| return bytes_copied; |
| } |
| |
| static int packet_read_list(char *data, size_t * pread_length) |
| { |
| struct list_head *ptemp_list; |
| int temp_count = 0; |
| int bytes_copied = 0; |
| int bytes_read = 0; |
| int remaining_bytes = 0; |
| char *pdest = data; |
| |
| /* check if we have any packets */ |
| if (0 == rbu_data.num_packets) |
| return -ENOMEM; |
| |
| remaining_bytes = *pread_length; |
| bytes_read = rbu_data.packet_read_count; |
| |
| ptemp_list = (&packet_data_head.list)->next; |
| while (!list_empty(ptemp_list)) { |
| bytes_copied = do_packet_read(pdest, ptemp_list, |
| remaining_bytes, bytes_read, &temp_count); |
| remaining_bytes -= bytes_copied; |
| bytes_read += bytes_copied; |
| pdest += bytes_copied; |
| /* |
| * check if we reached end of buffer before reaching the |
| * last packet |
| */ |
| if (remaining_bytes == 0) |
| break; |
| |
| ptemp_list = ptemp_list->next; |
| } |
| /*finally set the bytes read */ |
| *pread_length = bytes_read - rbu_data.packet_read_count; |
| rbu_data.packet_read_count = bytes_read; |
| return 0; |
| } |
| |
| static void packet_empty_list(void) |
| { |
| struct list_head *ptemp_list; |
| struct list_head *pnext_list; |
| struct packet_data *newpacket; |
| |
| ptemp_list = (&packet_data_head.list)->next; |
| while (!list_empty(ptemp_list)) { |
| newpacket = |
| list_entry(ptemp_list, struct packet_data, list); |
| pnext_list = ptemp_list->next; |
| list_del(ptemp_list); |
| ptemp_list = pnext_list; |
| /* |
| * zero out the RBU packet memory before freeing |
| * to make sure there are no stale RBU packets left in memory |
| */ |
| memset(newpacket->data, 0, rbu_data.packetsize); |
| set_memory_wb((unsigned long)newpacket->data, |
| 1 << newpacket->ordernum); |
| free_pages((unsigned long) newpacket->data, |
| newpacket->ordernum); |
| kfree(newpacket); |
| } |
| rbu_data.packet_read_count = 0; |
| rbu_data.num_packets = 0; |
| rbu_data.imagesize = 0; |
| } |
| |
| /* |
| * img_update_free: Frees the buffer allocated for storing BIOS image |
| * Always called with lock held and returned with lock held |
| */ |
| static void img_update_free(void) |
| { |
| if (!rbu_data.image_update_buffer) |
| return; |
| /* |
| * zero out this buffer before freeing it to get rid of any stale |
| * BIOS image copied in memory. |
| */ |
| memset(rbu_data.image_update_buffer, 0, |
| rbu_data.image_update_buffer_size); |
| free_pages((unsigned long) rbu_data.image_update_buffer, |
| rbu_data.image_update_ordernum); |
| |
| /* |
| * Re-initialize the rbu_data variables after a free |
| */ |
| rbu_data.image_update_ordernum = -1; |
| rbu_data.image_update_buffer = NULL; |
| rbu_data.image_update_buffer_size = 0; |
| rbu_data.bios_image_size = 0; |
| } |
| |
| /* |
| * img_update_realloc: This function allocates the contiguous pages to |
| * accommodate the requested size of data. The memory address and size |
| * values are stored globally and on every call to this function the new |
| * size is checked to see if more data is required than the existing size. |
| * If true the previous memory is freed and new allocation is done to |
| * accommodate the new size. If the incoming size is less then than the |
| * already allocated size, then that memory is reused. This function is |
| * called with lock held and returns with lock held. |
| */ |
| static int img_update_realloc(unsigned long size) |
| { |
| unsigned char *image_update_buffer = NULL; |
| unsigned long img_buf_phys_addr; |
| int ordernum; |
| |
| /* |
| * check if the buffer of sufficient size has been |
| * already allocated |
| */ |
| if (rbu_data.image_update_buffer_size >= size) { |
| /* |
| * check for corruption |
| */ |
| if ((size != 0) && (rbu_data.image_update_buffer == NULL)) { |
| printk(KERN_ERR "dell_rbu:%s: corruption " |
| "check failed\n", __func__); |
| return -EINVAL; |
| } |
| /* |
| * we have a valid pre-allocated buffer with |
| * sufficient size |
| */ |
| return 0; |
| } |
| |
| /* |
| * free any previously allocated buffer |
| */ |
| img_update_free(); |
| |
| spin_unlock(&rbu_data.lock); |
| |
| ordernum = get_order(size); |
| image_update_buffer = |
| (unsigned char *)__get_free_pages(GFP_DMA32, ordernum); |
| spin_lock(&rbu_data.lock); |
| if (!image_update_buffer) { |
| pr_debug("Not enough memory for image update:" |
| "size = %ld\n", size); |
| return -ENOMEM; |
| } |
| |
| img_buf_phys_addr = (unsigned long)virt_to_phys(image_update_buffer); |
| if (WARN_ON_ONCE(img_buf_phys_addr > BIOS_SCAN_LIMIT)) |
| return -EINVAL; /* can't happen per definition */ |
| |
| rbu_data.image_update_buffer = image_update_buffer; |
| rbu_data.image_update_buffer_size = size; |
| rbu_data.bios_image_size = rbu_data.image_update_buffer_size; |
| rbu_data.image_update_ordernum = ordernum; |
| return 0; |
| } |
| |
| static ssize_t read_packet_data(char *buffer, loff_t pos, size_t count) |
| { |
| int retval; |
| size_t bytes_left; |
| size_t data_length; |
| char *ptempBuf = buffer; |
| |
| /* check to see if we have something to return */ |
| if (rbu_data.num_packets == 0) { |
| pr_debug("read_packet_data: no packets written\n"); |
| retval = -ENOMEM; |
| goto read_rbu_data_exit; |
| } |
| |
| if (pos > rbu_data.imagesize) { |
| retval = 0; |
| printk(KERN_WARNING "dell_rbu:read_packet_data: " |
| "data underrun\n"); |
| goto read_rbu_data_exit; |
| } |
| |
| bytes_left = rbu_data.imagesize - pos; |
| data_length = min(bytes_left, count); |
| |
| if ((retval = packet_read_list(ptempBuf, &data_length)) < 0) |
| goto read_rbu_data_exit; |
| |
| if ((pos + count) > rbu_data.imagesize) { |
| rbu_data.packet_read_count = 0; |
| /* this was the last copy */ |
| retval = bytes_left; |
| } else |
| retval = count; |
| |
| read_rbu_data_exit: |
| return retval; |
| } |
| |
| static ssize_t read_rbu_mono_data(char *buffer, loff_t pos, size_t count) |
| { |
| /* check to see if we have something to return */ |
| if ((rbu_data.image_update_buffer == NULL) || |
| (rbu_data.bios_image_size == 0)) { |
| pr_debug("read_rbu_data_mono: image_update_buffer %p ," |
| "bios_image_size %lu\n", |
| rbu_data.image_update_buffer, |
| rbu_data.bios_image_size); |
| return -ENOMEM; |
| } |
| |
| return memory_read_from_buffer(buffer, count, &pos, |
| rbu_data.image_update_buffer, rbu_data.bios_image_size); |
| } |
| |
| static ssize_t read_rbu_data(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t pos, size_t count) |
| { |
| ssize_t ret_count = 0; |
| |
| spin_lock(&rbu_data.lock); |
| |
| if (!strcmp(image_type, "mono")) |
| ret_count = read_rbu_mono_data(buffer, pos, count); |
| else if (!strcmp(image_type, "packet")) |
| ret_count = read_packet_data(buffer, pos, count); |
| else |
| pr_debug("read_rbu_data: invalid image type specified\n"); |
| |
| spin_unlock(&rbu_data.lock); |
| return ret_count; |
| } |
| |
| static void callbackfn_rbu(const struct firmware *fw, void *context) |
| { |
| rbu_data.entry_created = 0; |
| |
| if (!fw) |
| return; |
| |
| if (!fw->size) |
| goto out; |
| |
| spin_lock(&rbu_data.lock); |
| if (!strcmp(image_type, "mono")) { |
| if (!img_update_realloc(fw->size)) |
| memcpy(rbu_data.image_update_buffer, |
| fw->data, fw->size); |
| } else if (!strcmp(image_type, "packet")) { |
| /* |
| * we need to free previous packets if a |
| * new hunk of packets needs to be downloaded |
| */ |
| packet_empty_list(); |
| if (packetize_data(fw->data, fw->size)) |
| /* Incase something goes wrong when we are |
| * in middle of packetizing the data, we |
| * need to free up whatever packets might |
| * have been created before we quit. |
| */ |
| packet_empty_list(); |
| } else |
| pr_debug("invalid image type specified.\n"); |
| spin_unlock(&rbu_data.lock); |
| out: |
| release_firmware(fw); |
| } |
| |
| static ssize_t read_rbu_image_type(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t pos, size_t count) |
| { |
| int size = 0; |
| if (!pos) |
| size = scnprintf(buffer, count, "%s\n", image_type); |
| return size; |
| } |
| |
| static ssize_t write_rbu_image_type(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t pos, size_t count) |
| { |
| int rc = count; |
| int req_firm_rc = 0; |
| int i; |
| spin_lock(&rbu_data.lock); |
| /* |
| * Find the first newline or space |
| */ |
| for (i = 0; i < count; ++i) |
| if (buffer[i] == '\n' || buffer[i] == ' ') { |
| buffer[i] = '\0'; |
| break; |
| } |
| if (i == count) |
| buffer[count] = '\0'; |
| |
| if (strstr(buffer, "mono")) |
| strcpy(image_type, "mono"); |
| else if (strstr(buffer, "packet")) |
| strcpy(image_type, "packet"); |
| else if (strstr(buffer, "init")) { |
| /* |
| * If due to the user error the driver gets in a bad |
| * state where even though it is loaded , the |
| * /sys/class/firmware/dell_rbu entries are missing. |
| * to cover this situation the user can recreate entries |
| * by writing init to image_type. |
| */ |
| if (!rbu_data.entry_created) { |
| spin_unlock(&rbu_data.lock); |
| req_firm_rc = request_firmware_nowait(THIS_MODULE, |
| FW_ACTION_NOHOTPLUG, "dell_rbu", |
| &rbu_device->dev, GFP_KERNEL, &context, |
| callbackfn_rbu); |
| if (req_firm_rc) { |
| printk(KERN_ERR |
| "dell_rbu:%s request_firmware_nowait" |
| " failed %d\n", __func__, rc); |
| rc = -EIO; |
| } else |
| rbu_data.entry_created = 1; |
| |
| spin_lock(&rbu_data.lock); |
| } |
| } else { |
| printk(KERN_WARNING "dell_rbu: image_type is invalid\n"); |
| spin_unlock(&rbu_data.lock); |
| return -EINVAL; |
| } |
| |
| /* we must free all previous allocations */ |
| packet_empty_list(); |
| img_update_free(); |
| spin_unlock(&rbu_data.lock); |
| |
| return rc; |
| } |
| |
| static ssize_t read_rbu_packet_size(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t pos, size_t count) |
| { |
| int size = 0; |
| if (!pos) { |
| spin_lock(&rbu_data.lock); |
| size = scnprintf(buffer, count, "%lu\n", rbu_data.packetsize); |
| spin_unlock(&rbu_data.lock); |
| } |
| return size; |
| } |
| |
| static ssize_t write_rbu_packet_size(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t pos, size_t count) |
| { |
| unsigned long temp; |
| spin_lock(&rbu_data.lock); |
| packet_empty_list(); |
| sscanf(buffer, "%lu", &temp); |
| if (temp < 0xffffffff) |
| rbu_data.packetsize = temp; |
| |
| spin_unlock(&rbu_data.lock); |
| return count; |
| } |
| |
| static struct bin_attribute rbu_data_attr = { |
| .attr = {.name = "data", .mode = 0444}, |
| .read = read_rbu_data, |
| }; |
| |
| static struct bin_attribute rbu_image_type_attr = { |
| .attr = {.name = "image_type", .mode = 0644}, |
| .read = read_rbu_image_type, |
| .write = write_rbu_image_type, |
| }; |
| |
| static struct bin_attribute rbu_packet_size_attr = { |
| .attr = {.name = "packet_size", .mode = 0644}, |
| .read = read_rbu_packet_size, |
| .write = write_rbu_packet_size, |
| }; |
| |
| static int __init dcdrbu_init(void) |
| { |
| int rc; |
| spin_lock_init(&rbu_data.lock); |
| |
| init_packet_head(); |
| rbu_device = platform_device_register_simple("dell_rbu", -1, NULL, 0); |
| if (IS_ERR(rbu_device)) { |
| printk(KERN_ERR |
| "dell_rbu:%s:platform_device_register_simple " |
| "failed\n", __func__); |
| return PTR_ERR(rbu_device); |
| } |
| |
| rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_data_attr); |
| if (rc) |
| goto out_devreg; |
| rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr); |
| if (rc) |
| goto out_data; |
| rc = sysfs_create_bin_file(&rbu_device->dev.kobj, |
| &rbu_packet_size_attr); |
| if (rc) |
| goto out_imtype; |
| |
| rbu_data.entry_created = 0; |
| return 0; |
| |
| out_imtype: |
| sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr); |
| out_data: |
| sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_data_attr); |
| out_devreg: |
| platform_device_unregister(rbu_device); |
| return rc; |
| } |
| |
| static __exit void dcdrbu_exit(void) |
| { |
| spin_lock(&rbu_data.lock); |
| packet_empty_list(); |
| img_update_free(); |
| spin_unlock(&rbu_data.lock); |
| platform_device_unregister(rbu_device); |
| } |
| |
| module_exit(dcdrbu_exit); |
| module_init(dcdrbu_init); |
| |
| /* vim:noet:ts=8:sw=8 |
| */ |