[patch 2.6.12-rc3] dell_rbu: Resubmitting patch for new Dell BIOS update driver

Abhay Salunke
2005-05-13T19:40:00Z

This is a resubmit of the patch after incorporating first round of
suggestson from Andrew Morton.

By making a contribution to this project, I certify that:
The contribution was created in whole or in part by me and I have the
right to submit it under the open source license indicated in the file.

Signed-off-by: Abhay Salunke <Abhay_Salunke@dell.com>

Thanks,
Abhay Salunke
Software Engineer.
DELL Inc

diff -uprN linux-2.6.11.8.ORIG/Documentation/DELL_RBU.txt linux-2.6.11.8/Documentation/DELL_RBU.txt
--- linux-2.6.11.8.ORIG/Documentation/DELL_RBU.txt 1969-12-31 18:00:00.000000000 -0600
+++ linux-2.6.11.8/Documentation/DELL_RBU.txt 2005-05-11 13:22:45.712684696 -0500
@@ -0,0 +1,92 @@
+Purpose:
+Demonstrate the usage of the DELL_RBU (DELL Remote BIOS Update) driver
+for updating BIOS images on Dell hardware.
+
+Scope:
+This document discusses the functionality of the DELL_RBU driver.
+This driver is required by BIOS update applications shipped by DELL for updating
+BIOS on DELL servers and client systems.
+
+Overview:
+The rbu driver is designed to be running on 2.6 kernel.
+This driver is one single dell_rbu.c file (approx 800 lines total).
+The BIOS update is done by writing the new BIOS image in to contiguous physical
+memory addressable by the BIOS. The user application indicates the BIOS regarding
+the update of a fresh image. The BIOS then scans the memory to find the image and
+it will then update itself. There are basically two different mechanisms for
+writing the BIOS image in to contiguous memory
+1> By writing the image to one single shunk of contiguous physical memory.
+2> By writing image in to smaller chunks of contiguous physical memory.
+The update mechanism is determined by the update application based on the
+particular system type.
+
+Update mechanism using single physical chunk of memory:
+The rbu driver on its load time created the following entries in sysfs
+/sys/firmware/rbu/rbudatasize
+/sys/firmware/rbu/rbudata
+
+Steps to update the BIOS image:
+
+1> Set the incoming BIOS image size in the /sys/firmware/rbudatasize file.
+
+ e.g. echo XXXXXX > /sys/firmware/rbudatasize
+NOTE: the size specified is always in decimal.
+
+you can also read back the image size by doing
+cat /sys/firmware/rbudatasize
+
+2> Download the BIOS image by copying the image file to /sys/firmware/rbudata
+file.
+e.g. cat image.hdr > /sys/firmware/rbudata
+
+you can also read back the image using
+cat /sys/firmware/rbu/rbudata
+This is usually helpful in verifying the image downloaded.
+
+Step#1 results in the driver allocating contiguous physical memory of the size
+echoed in to rbudatasize. The subsequent writes to rbudata as described in
+step #2 results in the image getting written to the allocated contiguous physical
+pages. Repeating step #2 will overwrite the previous data in rbudata file.
+
+On a driver unload the allocated memory is freed and the rbudatasize file reads 0.
+The user should not unload the driver after downloading the new BIOS image for
+if it wants to update BIOS with that image.
+
+The user can overwrite the rbudata file with a new image. The user has to make
+sure that the new image size is less than or equal to the image size copied to
+the rbudatasize file.
+If the new image is grater than the allocated size then only the allocated size
+gets copied the rest will not.
+
+The user can also free the previous BIOS image as follows
+echo 0 > /sys/firmware/rbu/rbudatasize
+
+If the user tries to set the BIOS image size there is a possiblity that the
+system may not have enough contiguous physical memory for upadtes, thus the
+image allocation will fail. The user the needs to verify this by reading back
+the rbudatasize which will be set to 0.
+
+Update using smaller chunks (packets) of contiguous memory:
+The disadvantage of contiguous allocation is that it may not be always possible
+to get that size of contiuguous chunk of avaliable physical pages as in most
+Linux systems the memory gets fragmented immideately after a reboot.
+The update using smaller chunks fixes this issue; it also requires the BIOS on
+the system to support this feature; the update application needs to query this
+with the BIOS on the system before using this technique.
+
+The appplication breaks the BIOS image in to small packets; before starting the
+update using this technique, the application sets the packetdatasize as follows
+
+echo XXXXXX > /sys/firmware/packetdatasize
+Any writes to /sys/firmware/packetdata results in allocation of contiguous
+physical memory of packetdatasize and the data is written to that meomry.
+Writing 0 to packetdatasize results in freeing of all packets.
+Unloading the driver will also result in freeing up of the allocated packets.
+
+NOTE:
+Afte updating the BIOS image the appplication needs to communicate with the BIOS
+for enabling the update on the next reboot. The application can then choose to
+reboot the system imideately or not reboot the system and leave up to the user
+to do a reboot.
+
+
diff -uprN linux-2.6.11.8.ORIG/drivers/firmware/dell_rbu.c linux-2.6.11.8/drivers/firmware/dell_rbu.c
--- linux-2.6.11.8.ORIG/drivers/firmware/dell_rbu.c 1969-12-31 18:00:00.000000000 -0600
+++ linux-2.6.11.8/drivers/firmware/dell_rbu.c 2005-05-13 12:38:20.047334448 -0500
@@ -0,0 +1,852 @@
+/*
+ * dell_rbu.c
+ * Bios Update driver for Dell systems
+ * Author: Dell Inc
+ * Abhay Salunke <abhay_salunke@dell.com>
+ *
+ * Copyright (C) 2004 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 to have some application to set the
+ * CMOS bit indicating the BIOS to update itself after a reboot.
+ *
+ * Contiguous method:
+ * This driver tries to allocates contiguos physical pages large enough
+ * to accomodate the BIOS image size specified by the user. The user
+ * supplied BIOS image is then copied in to the allocated contiguous pages.
+ *
+ * Packetized method:
+ * In case of packetized the driver provides entries in the /sys file systems
+ * as packetdatasize and packetdata. This driver requires an application to
+ * break the BIOS image in to fixed sized packet chunks and each packet is written
+ * to the packetdata entry. The packetdatasize needs to be set once and is fixed
+ * for all the packets.
+ *
+ * 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.
+ *
+ * Changelog:
+ *
+ * 13 May 2005 Abhay Salunke <Abhay_Salunke@dell.com>
+ * Modified code with suggestions from Andrew Morton;
+ *
+ */
+#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/firmware.h>
+#include <linux/spinlock.h>
+#include <linux/moduleparam.h>
+
+#define BIOS_SCAN_LIMIT 0xffffffff
+MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>");
+MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.6");
+
+static struct _rbu_data {
+ void *image_update_buffer;
+ unsigned long image_update_buffer_size;
+ unsigned long bios_image_size;
+ unsigned long image_update_order_number;
+ spinlock_t lock;
+ unsigned long packet_read_count;
+ unsigned long packet_write_count;
+ unsigned long num_packets;
+ unsigned long packetsize;
+} rbu_data;
+
+struct packet_data{
+ struct list_head list;
+ size_t length;
+ void *data;
+ int ordernum;
+};
+
+
+static struct packet_data packet_data_head;
+
+/* no default attributes yet. */
+static struct attribute * def_attrs[] = { NULL, };
+
+/* don't use show and store attribute functions */
+static struct sysfs_ops rbu_attr_ops = { };
+
+static struct kobj_type ktype_rbu = {
+ .sysfs_ops = &rbu_attr_ops,
+ .default_attrs = def_attrs,
+};
+
+static decl_subsys(rbu,&ktype_rbu,NULL);
+
+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 *ppacket = NULL;
+ int packet_count = 0;
+
+ pr_debug("fill_last_packet: entry \n");
+
+ /* check if we have any packets */
+ if (0 == 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)->next;
+
+ while(--packet_count) {
+ ptemp_list = ptemp_list->next;
+ }
+
+ ppacket = list_entry(ptemp_list,struct packet_data, list);
+
+ if ((rbu_data.packet_write_count + length) > rbu_data.packetsize) {
+ printk(KERN_WARNING "fill_last_packet: packet size data overrun\n");
+ return -ENOMEM;
+ }
+
+ pr_debug("fill_last_packet : buffer = %p\n", ppacket->data);
+
+ /* copy the incoming data in to the new buffer */
+ memcpy(((char *)ppacket->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 {
+ /* adjust the total packet length */
+ rbu_data.packet_write_count += length;
+ }
+ pr_debug("fill_last_packet: exit \n");
+ return 0;
+}
+
+/*
+ get_free_pages_limited:
+ This is a helper function which allocates free pages based on an upper limit.
+ On x86_64 or 64 bit arch the memory allocation goes above 4GB space which is
+ not addressable by the BIOS. This function tries to get allocation below the
+ limit (4GB) address. It first tries to allocate memory normally using the
+ GFP_KERNEL argument if the incoming limit is non-zero and if the returned
+ physical memory address exceeds the upper limit, the allocated pages are freed
+ and the memory is reallocated using the GFP_DMA argument.
+*/
+static void *get_free_pages_limited(unsigned long size,
+ int *ordernum,
+ unsigned long limit)
+{
+ unsigned long img_buf_phys_addr;
+ void *pbuf = NULL;
+
+ *ordernum = get_order(size);
+ /*
+ * Check if we are not getting a very large file. This can happen as a
+ * user error in entering the file size
+ */
+ if (*ordernum == BITS_PER_LONG) {
+ /* The incoming size is very large */
+ pr_debug("get_free_pages_limited: Incoming size is very large\n");
+ return NULL;
+ }
+
+ /* try allocating a new buffer to fit the request */
+ pbuf =(unsigned char *)__get_free_pages(GFP_KERNEL, *ordernum);
+
+ if (pbuf != NULL) {
+ /* check if the image is with in limits */
+ img_buf_phys_addr = (unsigned long)virt_to_phys((void *)pbuf);
+
+ if ((limit != 0) && ((img_buf_phys_addr + size) > limit)) {
+ pr_debug("Got memory above 4GB range, free this and try with DMA memory\n");
+ /* free this memory as we need it with in 4GB range */
+ free_pages ((unsigned long)pbuf, *ordernum);
+ /*
+ * Try allocating a new buffer from the GFP_DMA range
+ * as it is with in 16MB range.
+ */
+ pbuf =(unsigned char *)__get_free_pages(GFP_DMA, *ordernum);
+ if (pbuf == NULL)
+ pr_debug("Failed to get memory of size %ld using GFP_DMA\n", size);
+ }
+ }
+ return pbuf;
+}
+
+static int create_packet(size_t length)
+{
+ struct packet_data *newpacket;
+ int ordernum = 0;
+
+ pr_debug("create_packet: entry \n");
+
+ if (rbu_data.packetsize == 0 ) {
+ pr_debug("create_packet: packetsize not specified\n");
+ return -EINVAL;
+ }
+
+ newpacket = kmalloc(sizeof(struct packet_data) ,GFP_KERNEL);
+ if(newpacket == NULL) {
+ printk(KERN_WARNING"create_packet: failed to allocate new packet\n");
+ return -ENOMEM;
+ }
+
+ /* there is no upper limit on memory address for packetized mechanism */
+ newpacket->data = get_free_pages_limited(rbu_data.packetsize,&ordernum, 0);
+ pr_debug("create_packet: newpacket %p\n", newpacket->data);
+
+ if(newpacket->data == NULL) {
+ printk(KERN_WARNING"create_packet: failed to allocate new packet\n");
+ return -ENOMEM;
+ }
+
+ newpacket->ordernum = ordernum;
+ ++rbu_data.num_packets;
+ /* initialize the newly created packet headers */
+ INIT_LIST_HEAD(&newpacket->list);
+ /* add this packet to the link list */
+ list_add_tail(&newpacket->list, &packet_data_head.list);
+ /*
+ * packets are of fixed sizes so initialize
+ * the length to rbu_data.packetsize
+ */
+ 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;
+
+ pr_debug("packetize_data : entry\n");
+ if (rbu_data.packet_write_count == 0) {
+ /* create a new packet */
+ if ((rc = create_packet(length)) != 0 )
+ return rc;
+ }
+ /* fill data in to the packet */
+ if ((rc = fill_last_packet(data, length)) != 0)
+ return rc;
+
+ pr_debug("packetize_data : exit\n");
+ return rc;
+}
+
+
+/*
+ do_packet_read :
+ This is a helper function which reads the packet data of the
+ current list.
+ data: is the incoming buffer
+ ptemp_list: points to the incoming list item
+ length: is the length of the free space in the buffer.
+ bytes_read: is the total number of bytes read already from
+ the packet list
+ list_read_count: is the counter to keep track of the number
+ of bytes read out of each packet.
+*/
+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;
+}
+
+/*
+ packet_read_list:
+ This function reads the data out of the packet link list.
+ It will read data from multiple packets depending upon the
+ size of the incoming buffer.
+ data: is the incoming buffer pointer
+ *pread_length: is the length of the incoming buffer. At return
+ this value is adjusted to the actual size of the data read.
+*/
+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;
+ /* get the current read count */
+ bytes_read = rbu_data.packet_read_count;
+
+ ptemp_list = (&packet_data_head.list)->next;
+ while(!list_empty(ptemp_list)) {
+ /* read data */
+ bytes_copied = do_packet_read(pdest, ptemp_list, remaining_bytes,
+ bytes_read, &temp_count);
+ /* adjust the remaining bytes */
+ remaining_bytes -= bytes_copied;
+ bytes_read += bytes_copied;
+ /* adjust the data pointer */
+ pdest += bytes_copied;
+
+ /* check if we reached end of buffer before reaching the last packet*/
+ if (remaining_bytes == 0)
+ break;
+
+ /* point to the next packet in the list */
+ 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);
+ /* get the next list ptr before we delete this entry */
+ pnext_list = ptemp_list->next;
+ /* remove the list entry */
+ list_del(ptemp_list);
+ /* set the list to next */
+ ptemp_list = pnext_list;
+ /* zero out the RBU packet memory before freeing */
+ memset(newpacket->data, 0, rbu_data.packetsize);
+ /* free the memory pointed by this packet */
+ free_pages((unsigned long)newpacket->data, newpacket->ordernum);
+ /* now free the packet*/
+ kfree(newpacket);
+ }
+ rbu_data.packet_write_count = 0;
+ rbu_data.packet_read_count = 0;
+ rbu_data.num_packets = 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 == NULL)
+ return;
+
+ /* zero out this buffer before freeing it */
+ 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_order_number);
+ /* Re-initialize the rbu_data variables after a free */
+ 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 accomodate 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 accomodate 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 returna with lock held.
+*/
+static int img_update_realloc(unsigned long size)
+{
+ unsigned char *image_update_buffer = NULL;
+ unsigned long rc;
+ int ordernum =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)) {
+ pr_debug("img_update_realloc: corruption check failed\n");
+ return -EINVAL;
+ }
+ /* we have a valid pre-allocated buffer with sufficient size */
+ return 0;
+ }
+
+ /* free any previously allocated buffer */
+ img_update_free();
+
+ /* This has already been called as locked so we can now unlock
+ and proceed to calling get_free_pages_limited as this function
+ can sleep*/
+ spin_unlock(&rbu_data.lock);
+
+ image_update_buffer = (unsigned char *)get_free_pages_limited(size,
+ &ordernum,
+ BIOS_SCAN_LIMIT);
+
+ /* acquire the spinlock again */
+ spin_lock(&rbu_data.lock);
+
+ if (image_update_buffer != NULL) {
+ /* store address for the new buffer */
+ rbu_data.image_update_buffer = image_update_buffer;
+ /* adjust allocated size */
+ rbu_data.image_update_buffer_size = PAGE_SIZE << ordernum;
+ /* save the current order number */
+ rbu_data.image_update_order_number = ordernum;
+ /* initialize the new buffer data to 0 */
+ memset(rbu_data.image_update_buffer,0, rbu_data.image_update_buffer_size);
+ pr_debug("img_update_realloc: success\n");
+ /* success */
+ rc = 0;
+ } else {
+ pr_debug("Not enough memory for image update:order number = %d"
+ ",size = %ld\n",ordernum, size);
+ rc = -ENOMEM;
+ }
+
+ return rc;
+} /* img_update_realloc */
+
+
+/*
+ read_packet_data_size:
+ Returns the size of an RBU packet; if no packets present returns 0
+*/
+static ssize_t read_packet_data_size(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ unsigned int size = 0;
+ if (pos == 0)
+ size = sprintf(buffer, "%lu\n", rbu_data.packetsize);
+ return size;
+}
+
+/*
+ write_packet_data_size:
+ Writes the RBU data size supplied by the user, if the
+ data size supplied is non zero number, this function
+ records the packet size for any packet allocations.
+ If a byte size of zero is supplied this function will free
+ the previously allocated packets.
+*/
+static ssize_t write_packet_data_size(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ int retval = count;
+
+ spin_lock(&rbu_data.lock);
+ /* extract the image size */
+ sscanf(buffer, "%lu",&rbu_data.packetsize);
+ /* free the previous packet lists */
+ packet_empty_list();
+
+ spin_unlock(&rbu_data.lock);
+ return retval;
+}
+
+/*
+ read_rbu_data_size:
+ Returns the size of an RBU image previously downloaded
+ if no image is downloaded the size returned is 0
+*/
+static ssize_t read_rbu_data_size(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ unsigned int size = 0;
+ if (pos == 0)
+ size = sprintf(buffer, "%lu\n", rbu_data.bios_image_size);
+ return size;
+}
+
+/*
+ write_rbu_data_size:
+ Writes the RBU data size supplied by the user, if the
+ data size supplied is non zero number, this function
+ allocates the contiguous physical memory pages for the
+ supplied size , if it fails this function returns error.
+ If a byte size of zero is supplied this function will free
+ the previously allocated contiguous pages.
+*/
+static ssize_t write_rbu_data_size(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ int retval = count;
+
+ spin_lock(&rbu_data.lock);
+ /* extract the image size */
+ sscanf(buffer, "%lu",&rbu_data.bios_image_size);
+
+ if (rbu_data.bios_image_size !=0 ) {
+ if (img_update_realloc(rbu_data.bios_image_size) < 0) {
+ pr_debug("write_rbu_data_size: failed to allocate mem size %lu\n",
+ (unsigned long)rbu_data.bios_image_size);
+ rbu_data.bios_image_size = 0;
+ retval = -ENOMEM;
+ }
+ } else {
+ pr_debug(" freeing %ld size memory \n", rbu_data.bios_image_size);
+ /* free any allocated RBU memory */
+ img_update_free();
+ }
+
+ pr_debug("write_rbu_data_size: = %lu\n",
+ (unsigned long)rbu_data.bios_image_size);
+
+ spin_unlock(&rbu_data.lock);
+ return retval;
+} /* write_rbu_data_size*/
+
+/*
+ read_rbu_data:
+ Reads the BIOS image file from previously allocated contiguous physical
+ pages in to the buffer supplied in this call.
+ The reading is done in chunks of bytes supplied in the count argument.
+ The reading stops when the total number of bytes read equals the image
+ size given previously.
+ If image size is not specified or if the image size is zero this function
+ returns failure.
+ Parameters:
+ kobj is the kernel object
+ buffer is the pointer to the incoming data buffer.
+ count is the value of the incoming buffer size,
+ pos is the amount of bytes already read.
+*/
+static ssize_t read_rbu_data(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ unsigned char *ptemp = NULL;
+ int retval =0;
+ size_t bytes_left = 0;
+ size_t data_length = 0;
+
+ spin_lock(&rbu_data.lock);
+
+ /* 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: image_update_buffer %p ,"
+ "bios_image_size %lu\n",
+ rbu_data.image_update_buffer,
+ rbu_data.bios_image_size);
+ retval = -ENOMEM;
+ goto read_rbu_data_exit;
+ }
+
+ if ( pos > rbu_data.bios_image_size ) {
+ retval = 0;
+ goto read_rbu_data_exit;
+ }
+
+ bytes_left = rbu_data.bios_image_size - pos;
+ data_length = max(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 */
+ retval = bytes_left;
+ else
+ retval = count;
+
+read_rbu_data_exit:
+ spin_unlock(&rbu_data.lock);
+ return retval;
+}
+
+/*
+ write_rbu_data
+ Writes from the incoming BIOS image file to the pre-allocated
+ contiguous physical memory pages.
+ The writes occur in chunks of memory supplied by the count. The writes
+ stops when the total memory supplied equals the image size given previously.
+ If no memory size is previously specified or if the previously specified size
+ is zero the write returns error.
+*/
+static ssize_t write_rbu_data(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ unsigned char *pDest = NULL;
+ unsigned char *ptemp = NULL;
+ int retval = 0;
+
+ spin_lock(&rbu_data.lock);
+
+ /* check if the image size is given */
+ if (0 == rbu_data.bios_image_size) {
+ printk(KERN_WARNING"write_rbu_data: BIOS image size not set\n");
+ retval = -ENOMEM;
+ goto error_exit;
+ }
+
+ if ((pos + count) > rbu_data.bios_image_size) {
+ pr_debug("write_rbu_data: data_over_run, file pos %lu "
+ "bios_image_size %lu\n",
+ (unsigned long)pos,
+ rbu_data.bios_image_size);
+ retval = -ENOMEM;
+ goto error_exit;
+ }
+
+ pDest = (unsigned char*)rbu_data.image_update_buffer;
+ ptemp = pDest + pos;
+ memcpy(ptemp, buffer, count);
+ retval = count;
+ pr_debug("write_rbu_data : retval = %d\n", retval);
+error_exit:
+ spin_unlock(&rbu_data.lock);
+ return retval;
+}
+
+/*
+ read_rbu_packet_data:
+ Reads the BIOS image file from previously allocated contiguous physical
+ pages in to the buffer supplied in this call.
+ The reading is done in chunks of bytes supplied in the count argument.
+ The reading stops when the total number of bytes read equals the image
+ size given previously.
+ If image size is not specified or if the image size is zero this function
+ returns failure.
+ Parameters:
+ kobj is the kernel object
+ buffer is the pointer to the incoming data buffer.
+ count is the value of the incoming buffer size,
+ pos is the amount of bytes already read.
+*/
+static ssize_t read_rbu_packet_data(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ int retval;
+ size_t bytes_left;
+ size_t data_length;
+ char *ptempBuf = buffer;
+ unsigned long imagesize;
+
+ spin_lock(&rbu_data.lock);
+
+ /* check to see if we have something to return */
+ if (rbu_data.num_packets == 0) {
+ pr_debug("read_rbu_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"read_rbu_packet_data: data underrun\n");
+ goto read_rbu_data_exit;
+ }
+
+ bytes_left = imagesize - pos;
+ data_length = max(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:
+ spin_unlock(&rbu_data.lock);
+ return retval;
+}
+
+/*
+ write_rbu_packet_data
+ Writes from the incoming BIOS image file to the pre-allocated
+ contiguous physical memory pages.
+ The writes occur in chunks of memory supplied by the count. The writes
+ stops when the total memory supplied equals the image size given previously.
+ If no memory size is previously specified or if the previously specified size
+ is zero the write returns error.
+*/
+static ssize_t write_rbu_packet_data(struct kobject *kobj,
+ char *buffer,
+ loff_t pos,
+ size_t count)
+{
+ int retval = 0;
+
+ spin_lock(&rbu_data.lock);
+
+ /* check if the packet size is given */
+ if (0 == rbu_data.packetsize) {
+ printk(KERN_WARNING"write_rbu_packet_data: packetsize not set\n");
+ retval = -ENOMEM;
+ goto error_exit;
+ }
+
+ if ((pos + count) > rbu_data.packetsize) {
+ pr_debug("write_rbu_packet_data: data_over_run, file pos %lu,"
+ "packetsize %lu\n",
+ (unsigned long)pos,
+ rbu_data.packetsize);
+ retval = -ENOMEM;
+
+ /* We have a write data overrun, obviously this is
+ not the corret file, so free the previous data*/
+ pr_debug("data overrun freeing all the previous packets\n");
+ packet_empty_list();
+ goto error_exit;
+ }
+
+ if ((retval = packetize_data(buffer, count)) < 0 ) {
+ pr_debug(KERN_WARNING"write_rbu_packet_data: packetize_data "
+ "failed with status %d\n", retval);
+ retval = -EIO;
+ goto error_exit;
+ }
+
+ retval = count;
+
+ pr_debug("write_rbu_packet_data : retval = %d\n", retval);
+
+error_exit:
+ spin_unlock(&rbu_data.lock);
+ return retval;
+}
+
+
+static struct bin_attribute rbudata_attr = {
+ .attr = {.name = "rbudata", .owner = THIS_MODULE, .mode = 0644},
+ .read = read_rbu_data,
+ .write = write_rbu_data,
+};
+
+static struct bin_attribute rbudatasize_attr = {
+ .attr = { .name = "rbudatasize", .owner = THIS_MODULE, .mode = 0644 },
+ .read = read_rbu_data_size,
+ .write= write_rbu_data_size,
+};
+
+static struct bin_attribute packetdatasize_attr = {
+ .attr = { .name = "packetdatasize", .owner = THIS_MODULE, .mode = 0644 },
+ .read = read_packet_data_size,
+ .write= write_packet_data_size,
+};
+
+static struct bin_attribute packetdata_attr = {
+ .attr = { .name = "packetdata", .owner = THIS_MODULE, .mode = 0644 },
+ .read = read_rbu_packet_data,
+ .write= write_rbu_packet_data,
+};
+
+static int __init dcdrbu_init(void)
+{
+ int rc;
+
+ spin_lock_init(&rbu_data.lock);
+
+ init_packet_head();
+
+ rc = firmware_register(&rbu_subsys);
+ if (rc < 0) {
+ printk(KERN_WARNING"dcdrbu_init: firmware_register failed\n");
+ return rc;
+ }
+
+ sysfs_create_bin_file(&rbu_subsys.kset.kobj,&rbudata_attr);
+ sysfs_create_bin_file(&rbu_subsys.kset.kobj,&rbudatasize_attr);
+ sysfs_create_bin_file(&rbu_subsys.kset.kobj,&packetdatasize_attr);
+ sysfs_create_bin_file(&rbu_subsys.kset.kobj,&packetdata_attr);
+
+ return rc;
+}
+
+static __exit void dcdrbu_exit( void)
+{
+ spin_lock(&rbu_data.lock);
+ packet_empty_list();
+ img_update_free();
+ spin_unlock(&rbu_data.lock);
+ sysfs_remove_bin_file(&rbu_subsys.kset.kobj, &rbudata_attr );
+ sysfs_remove_bin_file(&rbu_subsys.kset.kobj, &rbudatasize_attr );
+ sysfs_remove_bin_file(&rbu_subsys.kset.kobj, &packetdatasize_attr );
+ sysfs_remove_bin_file(&rbu_subsys.kset.kobj, &packetdata_attr );
+ firmware_unregister(&rbu_subsys);
+}
+
+module_exit(dcdrbu_exit);
+module_init(dcdrbu_init);
+
diff -uprN linux-2.6.11.8.ORIG/drivers/firmware/Kconfig linux-2.6.11.8/drivers/firmware/Kconfig
--- linux-2.6.11.8.ORIG/drivers/firmware/Kconfig 2005-05-13 12:07:58.965181016 -0500
+++ linux-2.6.11.8/drivers/firmware/Kconfig 2005-05-13 12:07:00.566059032 -0500
@@ -58,4 +58,16 @@ config EFI_PCDP

See <http://www.dig64.org/specifications/DIG64_HCDPv20_042804.pdf>

+config DELL_RBU
+ tristate "BIOS update support for DELL systems via sysfs"
+ default n
+ help
+ Say Y if you want to have the option of updating the BIOS for your
+ DELL system. Note you need a supporting application to comunicate
+ with the BIOS regardign the new image for the image update to
+ take effect.
+
+ See <file:Documentation/DELL_RBU.txt> for more details on the driver.
+
+
endmenu
diff -uprN linux-2.6.11.8.ORIG/drivers/firmware/Makefile linux-2.6.11.8/drivers/firmware/Makefile
--- linux-2.6.11.8.ORIG/drivers/firmware/Makefile 2005-05-13 12:08:12.839071864 -0500
+++ linux-2.6.11.8/drivers/firmware/Makefile 2005-05-09 15:15:16.000000000 -0500
@@ -4,3 +4,4 @@
obj-$(CONFIG_EDD) += edd.o
obj-$(CONFIG_EFI_VARS) += efivars.o
obj-$(CONFIG_EFI_PCDP) += pcdp.o
+obj-$(CONFIG_DELL_RBU) += dell_rbu.o