diff options
Diffstat (limited to 'drivers/firmware/dell_rbu.c')
-rw-r--r-- | drivers/firmware/dell_rbu.c | 634 |
1 files changed, 634 insertions, 0 deletions
diff --git a/drivers/firmware/dell_rbu.c b/drivers/firmware/dell_rbu.c new file mode 100644 index 00000000000..3b865f34a09 --- /dev/null +++ b/drivers/firmware/dell_rbu.c @@ -0,0 +1,634 @@ +/* + * 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/version.h> +#include <linux/config.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/blkdev.h> +#include <linux/device.h> +#include <linux/spinlock.h> +#include <linux/moduleparam.h> +#include <linux/firmware.h> +#include <linux/dma-mapping.h> + +MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>"); +MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1.0"); + +#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; + int dma_alloc; + spinlock_t lock; + unsigned long packet_read_count; + unsigned long packet_write_count; + unsigned long num_packets; + unsigned long packetsize; +} rbu_data; + +static char image_type[MAX_IMAGE_LENGTH] = "mono"; +module_param_string(image_type, image_type, sizeof(image_type), 0); +MODULE_PARM_DESC(image_type, "BIOS image type. choose- mono or packet"); + +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 dma_addr_t dell_rbu_dmaaddr; + +static void init_packet_head(void) +{ + INIT_LIST_HEAD(&packet_data_head.list); + rbu_data.packet_write_count = 0; + rbu_data.packet_read_count = 0; + rbu_data.num_packets = 0; + rbu_data.packetsize = 0; +} + +static int fill_last_packet(void *data, size_t length) +{ + struct list_head *ptemp_list; + struct packet_data *packet = NULL; + int packet_count = 0; + + pr_debug("fill_last_packet: entry \n"); + + if (!rbu_data.num_packets) { + pr_debug("fill_last_packet: num_packets=0\n"); + return -ENOMEM; + } + + packet_count = rbu_data.num_packets; + + ptemp_list = (&packet_data_head.list)->prev; + + packet = list_entry(ptemp_list, struct packet_data, list); + + if ((rbu_data.packet_write_count + length) > rbu_data.packetsize) { + pr_debug("dell_rbu:%s: packet size data " + "overrun\n", __FUNCTION__); + return -EINVAL; + } + + pr_debug("fill_last_packet : buffer = %p\n", packet->data); + + memcpy((packet->data + rbu_data.packet_write_count), data, length); + + if ((rbu_data.packet_write_count + length) == rbu_data.packetsize) { + /* + * this was the last data chunk in the packet + * so reinitialize the packet data counter to zero + */ + rbu_data.packet_write_count = 0; + } else + rbu_data.packet_write_count += length; + + pr_debug("fill_last_packet: exit \n"); + return 0; +} + +static int create_packet(size_t length) +{ + struct packet_data *newpacket; + int ordernum = 0; + + pr_debug("create_packet: entry \n"); + + if (!rbu_data.packetsize) { + pr_debug("create_packet: packetsize not specified\n"); + return -EINVAL; + } + + newpacket = kmalloc(sizeof(struct packet_data), GFP_KERNEL); + if (!newpacket) { + printk(KERN_WARNING + "dell_rbu:%s: failed to allocate new " + "packet\n", __FUNCTION__); + return -ENOMEM; + } + + ordernum = get_order(length); + /* + * there is no upper limit on memory + * address for packetized mechanism + */ + newpacket->data = (unsigned char *)__get_free_pages(GFP_KERNEL, + ordernum); + + pr_debug("create_packet: newpacket %p\n", newpacket->data); + + if (!newpacket->data) { + printk(KERN_WARNING + "dell_rbu:%s: failed to allocate new " + "packet\n", __FUNCTION__); + kfree(newpacket); + return -ENOMEM; + } + + 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); + /* + * packets have fixed size + */ + newpacket->length = rbu_data.packetsize; + + pr_debug("create_packet: exit \n"); + + return 0; +} + +static int packetize_data(void *data, size_t length) +{ + int rc = 0; + + if (!rbu_data.packet_write_count) { + if ((rc = create_packet(length))) + return rc; + } + if ((rc = fill_last_packet(data, length))) + return rc; + + 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); + free_pages((unsigned long)newpacket->data, + newpacket->ordernum); + kfree(newpacket); + } + rbu_data.packet_write_count = 0; + rbu_data.packet_read_count = 0; + rbu_data.num_packets = 0; + rbu_data.packetsize = 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); + if (rbu_data.dma_alloc == 1) + dma_free_coherent(NULL, rbu_data.bios_image_size, + rbu_data.image_update_buffer, + dell_rbu_dmaaddr); + else + 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; + rbu_data.dma_alloc = 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 rc; + unsigned long img_buf_phys_addr; + int ordernum; + int dma_alloc = 0; + + /* + * 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", __FUNCTION__); + 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_KERNEL, ordernum); + + img_buf_phys_addr = + (unsigned long)virt_to_phys(image_update_buffer); + + if (img_buf_phys_addr > BIOS_SCAN_LIMIT) { + free_pages((unsigned long)image_update_buffer, ordernum); + ordernum = -1; + image_update_buffer = dma_alloc_coherent(NULL, size, + &dell_rbu_dmaaddr, + GFP_KERNEL); + dma_alloc = 1; + } + + spin_lock(&rbu_data.lock); + + if (image_update_buffer != NULL) { + 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; + rbu_data.dma_alloc = dma_alloc; + rc = 0; + } else { + pr_debug("Not enough memory for image update:" + "size = %ld\n", size); + rc = -ENOMEM; + } + + return rc; +} + +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; + unsigned long imagesize; + + /* 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; + } + + imagesize = rbu_data.num_packets * rbu_data.packetsize; + + if (pos > imagesize) { + retval = 0; + printk(KERN_WARNING "dell_rbu:read_packet_data: " + "data underrun\n"); + goto read_rbu_data_exit; + } + + bytes_left = 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) > 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) +{ + unsigned char *ptemp = NULL; + size_t bytes_left = 0; + size_t data_length = 0; + ssize_t ret_count = 0; + + /* 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); + ret_count = -ENOMEM; + goto read_rbu_data_exit; + } + + if (pos > rbu_data.bios_image_size) { + ret_count = 0; + goto read_rbu_data_exit; + } + + bytes_left = rbu_data.bios_image_size - pos; + data_length = min(bytes_left, count); + + ptemp = rbu_data.image_update_buffer; + memcpy(buffer, (ptemp + pos), data_length); + + if ((pos + count) > rbu_data.bios_image_size) + /* this was the last copy */ + ret_count = bytes_left; + else + ret_count = count; + read_rbu_data_exit: + return ret_count; +} + +static ssize_t +read_rbu_data(struct kobject *kobj, 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 ssize_t +read_rbu_image_type(struct kobject *kobj, char *buffer, loff_t pos, + size_t count) +{ + int size = 0; + if (!pos) + size = sprintf(buffer, "%s\n", image_type); + return size; +} + +static ssize_t +write_rbu_image_type(struct kobject *kobj, char *buffer, loff_t pos, + size_t count) +{ + int rc = count; + spin_lock(&rbu_data.lock); + + if (strlen(buffer) < MAX_IMAGE_LENGTH) + sscanf(buffer, "%s", image_type); + else + printk(KERN_WARNING "dell_rbu: image_type is invalid" + "max chars = %d, \n incoming str--%s-- \n", + MAX_IMAGE_LENGTH, buffer); + + /* we must free all previous allocations */ + packet_empty_list(); + img_update_free(); + + spin_unlock(&rbu_data.lock); + return rc; + +} + +static struct bin_attribute rbu_data_attr = { + .attr = {.name = "data",.owner = THIS_MODULE,.mode = 0444}, + .read = read_rbu_data, +}; + +static struct bin_attribute rbu_image_type_attr = { + .attr = {.name = "image_type",.owner = THIS_MODULE,.mode = 0644}, + .read = read_rbu_image_type, + .write = write_rbu_image_type, +}; + +static void callbackfn_rbu(const struct firmware *fw, void *context) +{ + int rc = 0; + + if (!fw || !fw->size) + return; + + 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")) { + if (!rbu_data.packetsize) + rbu_data.packetsize = fw->size; + else if (rbu_data.packetsize != fw->size) { + packet_empty_list(); + rbu_data.packetsize = fw->size; + } + packetize_data(fw->data, fw->size); + } else + pr_debug("invalid image type specified.\n"); + spin_unlock(&rbu_data.lock); + + rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG, + "dell_rbu", &rbu_device->dev, + &context, callbackfn_rbu); + if (rc) + printk(KERN_ERR + "dell_rbu:%s request_firmware_nowait failed" + " %d\n", __FUNCTION__, rc); +} + +static int __init dcdrbu_init(void) +{ + int rc = 0; + spin_lock_init(&rbu_data.lock); + + init_packet_head(); + rbu_device = + platform_device_register_simple("dell_rbu", -1, NULL, 0); + if (!rbu_device) { + printk(KERN_ERR + "dell_rbu:%s:platform_device_register_simple " + "failed\n", __FUNCTION__); + return -EIO; + } + + sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_data_attr); + sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr); + + rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG, + "dell_rbu", &rbu_device->dev, + &context, callbackfn_rbu); + if (rc) + printk(KERN_ERR "dell_rbu:%s:request_firmware_nowait" + " failed %d\n", __FUNCTION__, rc); + + 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); |