rtas_flash.c

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/*
 *  c 2001 PPC 64 Team, IBM Corp
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 * /proc/powerpc/rtas/firmware_flash interface
 *
 * This file implements a firmware_flash interface to pump a firmware
 * image into the kernel.  At reboot time rtas_restart() will see the
 * firmware image and flash it as it reboots (see rtas.c).
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include <linux/reboot.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
#include <asm/rtas.h>

#define MODULE_VERS "1.0"
#define MODULE_NAME "rtas_flash"

#define FIRMWARE_FLASH_NAME "firmware_flash"   
#define FIRMWARE_UPDATE_NAME "firmware_update"
#define MANAGE_FLASH_NAME "manage_flash"
#define VALIDATE_FLASH_NAME "validate_flash"

/* General RTAS Status Codes */
#define RTAS_RC_SUCCESS  0
#define RTAS_RC_HW_ERR  -1
#define RTAS_RC_BUSY    -2

/* Flash image status values */
#define FLASH_AUTH           -9002 /* RTAS Not Service Authority Partition */
#define FLASH_NO_OP          -1099 /* No operation initiated by user */ 
#define FLASH_IMG_SHORT      -1005 /* Flash image shorter than expected */
#define FLASH_IMG_BAD_LEN    -1004 /* Bad length value in flash list block */
#define FLASH_IMG_NULL_DATA  -1003 /* Bad data value in flash list block */
#define FLASH_IMG_READY      0     /* Firmware img ready for flash on reboot */

/* Manage image status values */
#define MANAGE_AUTH          -9002 /* RTAS Not Service Authority Partition */
#define MANAGE_ACTIVE_ERR    -9001 /* RTAS Cannot Overwrite Active Img */
#define MANAGE_NO_OP         -1099 /* No operation initiated by user */
#define MANAGE_PARAM_ERR     -3    /* RTAS Parameter Error */
#define MANAGE_HW_ERR        -1    /* RTAS Hardware Error */

/* Validate image status values */
#define VALIDATE_AUTH          -9002 /* RTAS Not Service Authority Partition */
#define VALIDATE_NO_OP         -1099 /* No operation initiated by the user */
#define VALIDATE_INCOMPLETE    -1002 /* User copied < VALIDATE_BUF_SIZE */
#define VALIDATE_READY         -1001 /* Firmware image ready for validation */
#define VALIDATE_PARAM_ERR     -3    /* RTAS Parameter Error */
#define VALIDATE_HW_ERR        -1    /* RTAS Hardware Error */
#define VALIDATE_TMP_UPDATE    0     /* Validate Return Status */
#define VALIDATE_FLASH_AUTH    1     /* Validate Return Status */
#define VALIDATE_INVALID_IMG   2     /* Validate Return Status */
#define VALIDATE_CUR_UNKNOWN   3     /* Validate Return Status */
#define VALIDATE_TMP_COMMIT_DL 4     /* Validate Return Status */
#define VALIDATE_TMP_COMMIT    5     /* Validate Return Status */
#define VALIDATE_TMP_UPDATE_DL 6     /* Validate Return Status */

/* ibm,manage-flash-image operation tokens */
#define RTAS_REJECT_TMP_IMG   0
#define RTAS_COMMIT_TMP_IMG   1

/* Array sizes */
#define VALIDATE_BUF_SIZE 4096    
#define RTAS_MSG_MAXLEN   64

/* Quirk - RTAS requires 4k list length and block size */
#define RTAS_BLKLIST_LENGTH 4096
#define RTAS_BLK_SIZE 4096

struct flash_block {
    char *data;
    unsigned long length;
};

/* This struct is very similar but not identical to
 * that needed by the rtas flash update.
 * All we need to do for rtas is rewrite num_blocks
 * into a version/length and translate the pointers
 * to absolute.
 */
#define FLASH_BLOCKS_PER_NODE ((RTAS_BLKLIST_LENGTH - 16) / sizeof(struct flash_block))
struct flash_block_list {
    unsigned long num_blocks;
    struct flash_block_list *next;
    struct flash_block blocks[FLASH_BLOCKS_PER_NODE];
};

static struct flash_block_list *rtas_firmware_flash_list;

/* Use slab cache to guarantee 4k alignment */
static struct kmem_cache *flash_block_cache = NULL;

#define FLASH_BLOCK_LIST_VERSION (1UL)

/* Local copy of the flash block list.
 * We only allow one open of the flash proc file and create this
 * list as we go.  The rtas_firmware_flash_list varable will be
 * set once the data is fully read.
 *
 * For convenience as we build the list we use virtual addrs,
 * we do not fill in the version number, and the length field
 * is treated as the number of entries currently in the block
 * (i.e. not a byte count).  This is all fixed when calling 
 * the flash routine.
 */

/* Status int must be first member of struct */
struct rtas_update_flash_t
{
    int status;         /* Flash update status */
    struct flash_block_list *flist; /* Local copy of flash block list */
};

/* Status int must be first member of struct */
struct rtas_manage_flash_t
{
    int status;         /* Returned status */
    unsigned int op;        /* Reject or commit image */
};

/* Status int must be first member of struct */
struct rtas_validate_flash_t
{
    int status;         /* Returned status */   
    char buf[VALIDATE_BUF_SIZE];    /* Candidate image buffer */
    unsigned int buf_size;      /* Size of image buf */
    unsigned int update_results;    /* Update results token */
};

static DEFINE_SPINLOCK(flash_file_open_lock);
static struct proc_dir_entry *firmware_flash_pde;
static struct proc_dir_entry *firmware_update_pde;
static struct proc_dir_entry *validate_pde;
static struct proc_dir_entry *manage_pde;

/* Do simple sanity checks on the flash image. */
static int flash_list_valid(struct flash_block_list *flist)
{
    struct flash_block_list *f;
    int i;
    unsigned long block_size, image_size;

    /* Paranoid self test here.  We also collect the image size. */
    image_size = 0;
    for (f = flist; f; f = f->next) {
        for (i = 0; i < f->num_blocks; i++) {
            if (f->blocks[i].data == NULL) {
                return FLASH_IMG_NULL_DATA;
            }
            block_size = f->blocks[i].length;
            if (block_size <= 0 || block_size > RTAS_BLK_SIZE) {
                return FLASH_IMG_BAD_LEN;
            }
            image_size += block_size;
        }
    }

    if (image_size < (256 << 10)) {
        if (image_size < 2) 
            return FLASH_NO_OP;
    }

    printk(KERN_INFO "FLASH: flash image with %ld bytes stored for hardware flash on reboot\n", image_size);

    return FLASH_IMG_READY;
}

static void free_flash_list(struct flash_block_list *f)
{
    struct flash_block_list *next;
    int i;

    while (f) {
        for (i = 0; i < f->num_blocks; i++)
            kmem_cache_free(flash_block_cache, f->blocks[i].data);
        next = f->next;
        kmem_cache_free(flash_block_cache, f);
        f = next;
    }
}

static int rtas_flash_release(struct inode *inode, struct file *file)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_update_flash_t *uf;
    
    uf = (struct rtas_update_flash_t *) dp->data;
    if (uf->flist) {    
        /* File was opened in write mode for a new flash attempt */
        /* Clear saved list */
        if (rtas_firmware_flash_list) {
            free_flash_list(rtas_firmware_flash_list);
            rtas_firmware_flash_list = NULL;
        }

        if (uf->status != FLASH_AUTH)  
            uf->status = flash_list_valid(uf->flist);

        if (uf->status == FLASH_IMG_READY) 
            rtas_firmware_flash_list = uf->flist;
        else
            free_flash_list(uf->flist);

        uf->flist = NULL;
    }

    atomic_dec(&dp->count);
    return 0;
}

static void get_flash_status_msg(int status, char *buf)
{
    char *msg;

    switch (status) {
    case FLASH_AUTH:
        msg = "error: this partition does not have service authority\n";
        break;
    case FLASH_NO_OP:
        msg = "info: no firmware image for flash\n";
        break;
    case FLASH_IMG_SHORT:
        msg = "error: flash image short\n";
        break;
    case FLASH_IMG_BAD_LEN:
        msg = "error: internal error bad length\n";
        break;
    case FLASH_IMG_NULL_DATA:
        msg = "error: internal error null data\n";
        break;
    case FLASH_IMG_READY:
        msg = "ready: firmware image ready for flash on reboot\n";
        break;
    default:
        sprintf(buf, "error: unexpected status value %d\n", status);
        return;
    }

    strcpy(buf, msg);   
}

/* Reading the proc file will show status (not the firmware contents) */
static ssize_t rtas_flash_read(struct file *file, char __user *buf,
                   size_t count, loff_t *ppos)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_update_flash_t *uf;
    char msg[RTAS_MSG_MAXLEN];

    uf = dp->data;

    if (!strcmp(dp->name, FIRMWARE_FLASH_NAME)) {
        get_flash_status_msg(uf->status, msg);
    } else {       /* FIRMWARE_UPDATE_NAME */
        sprintf(msg, "%d\n", uf->status);
    }

    return simple_read_from_buffer(buf, count, ppos, msg, strlen(msg));
}

/* constructor for flash_block_cache */
void rtas_block_ctor(void *ptr)
{
    memset(ptr, 0, RTAS_BLK_SIZE);
}

/* We could be much more efficient here.  But to keep this function
 * simple we allocate a page to the block list no matter how small the
 * count is.  If the system is low on memory it will be just as well
 * that we fail....
 */
static ssize_t rtas_flash_write(struct file *file, const char __user *buffer,
                size_t count, loff_t *off)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_update_flash_t *uf;
    char *p;
    int next_free;
    struct flash_block_list *fl;

    uf = (struct rtas_update_flash_t *) dp->data;

    if (uf->status == FLASH_AUTH || count == 0)
        return count;   /* discard data */

    /* In the case that the image is not ready for flashing, the memory
     * allocated for the block list will be freed upon the release of the 
     * proc file
     */
    if (uf->flist == NULL) {
        uf->flist = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
        if (!uf->flist)
            return -ENOMEM;
    }

    fl = uf->flist;
    while (fl->next)
        fl = fl->next; /* seek to last block_list for append */
    next_free = fl->num_blocks;
    if (next_free == FLASH_BLOCKS_PER_NODE) {
        /* Need to allocate another block_list */
        fl->next = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
        if (!fl->next)
            return -ENOMEM;
        fl = fl->next;
        next_free = 0;
    }

    if (count > RTAS_BLK_SIZE)
        count = RTAS_BLK_SIZE;
    p = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
    if (!p)
        return -ENOMEM;
    
    if(copy_from_user(p, buffer, count)) {
        kmem_cache_free(flash_block_cache, p);
        return -EFAULT;
    }
    fl->blocks[next_free].data = p;
    fl->blocks[next_free].length = count;
    fl->num_blocks++;

    return count;
}

static int rtas_excl_open(struct inode *inode, struct file *file)
{
    struct proc_dir_entry *dp = PDE(inode);

    /* Enforce exclusive open with use count of PDE */
    spin_lock(&flash_file_open_lock);
    if (atomic_read(&dp->count) > 2) {
        spin_unlock(&flash_file_open_lock);
        return -EBUSY;
    }

    atomic_inc(&dp->count);
    spin_unlock(&flash_file_open_lock);
    
    return 0;
}

static int rtas_excl_release(struct inode *inode, struct file *file)
{
    struct proc_dir_entry *dp = PDE(inode);

    atomic_dec(&dp->count);

    return 0;
}

static void manage_flash(struct rtas_manage_flash_t *args_buf)
{
    s32 rc;

    do {
        rc = rtas_call(rtas_token("ibm,manage-flash-image"), 1, 
                   1, NULL, args_buf->op);
    } while (rtas_busy_delay(rc));

    args_buf->status = rc;
}

static ssize_t manage_flash_read(struct file *file, char __user *buf,
                   size_t count, loff_t *ppos)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_manage_flash_t *args_buf;
    char msg[RTAS_MSG_MAXLEN];
    int msglen;

    args_buf = dp->data;
    if (args_buf == NULL)
        return 0;

    msglen = sprintf(msg, "%d\n", args_buf->status);

    return simple_read_from_buffer(buf, count, ppos, msg, msglen);
}

static ssize_t manage_flash_write(struct file *file, const char __user *buf,
                size_t count, loff_t *off)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_manage_flash_t *args_buf;
    const char reject_str[] = "0";
    const char commit_str[] = "1";
    char stkbuf[10];
    int op;

    args_buf = (struct rtas_manage_flash_t *) dp->data;
    if ((args_buf->status == MANAGE_AUTH) || (count == 0))
        return count;
        
    op = -1;
    if (buf) {
        if (count > 9) count = 9;
        if (copy_from_user (stkbuf, buf, count)) {
            return -EFAULT;
        }
        if (strncmp(stkbuf, reject_str, strlen(reject_str)) == 0) 
            op = RTAS_REJECT_TMP_IMG;
        else if (strncmp(stkbuf, commit_str, strlen(commit_str)) == 0) 
            op = RTAS_COMMIT_TMP_IMG;
    }
    
    if (op == -1)   /* buf is empty, or contains invalid string */
        return -EINVAL;

    args_buf->op = op;
    manage_flash(args_buf);

    return count;
}

static void validate_flash(struct rtas_validate_flash_t *args_buf)
{
    int token = rtas_token("ibm,validate-flash-image");
    int update_results;
    s32 rc; 

    rc = 0;
    do {
        spin_lock(&rtas_data_buf_lock);
        memcpy(rtas_data_buf, args_buf->buf, VALIDATE_BUF_SIZE);
        rc = rtas_call(token, 2, 2, &update_results, 
                   (u32) __pa(rtas_data_buf), args_buf->buf_size);
        memcpy(args_buf->buf, rtas_data_buf, VALIDATE_BUF_SIZE);
        spin_unlock(&rtas_data_buf_lock);
    } while (rtas_busy_delay(rc));

    args_buf->status = rc;
    args_buf->update_results = update_results;
}

static int get_validate_flash_msg(struct rtas_validate_flash_t *args_buf, 
                           char *msg)
{
    int n;

    if (args_buf->status >= VALIDATE_TMP_UPDATE) { 
        n = sprintf(msg, "%d\n", args_buf->update_results);
        if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) ||
            (args_buf->update_results == VALIDATE_TMP_UPDATE))
            n += sprintf(msg + n, "%s\n", args_buf->buf);
    } else {
        n = sprintf(msg, "%d\n", args_buf->status);
    }
    return n;
}

static ssize_t validate_flash_read(struct file *file, char __user *buf,
                   size_t count, loff_t *ppos)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_validate_flash_t *args_buf;
    char msg[RTAS_MSG_MAXLEN];
    int msglen;

    args_buf = dp->data;

    msglen = get_validate_flash_msg(args_buf, msg);

    return simple_read_from_buffer(buf, count, ppos, msg, msglen);
}

static ssize_t validate_flash_write(struct file *file, const char __user *buf,
                    size_t count, loff_t *off)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_validate_flash_t *args_buf;
    int rc;

    args_buf = (struct rtas_validate_flash_t *) dp->data;

    if (dp->data == NULL) {
        dp->data = kmalloc(sizeof(struct rtas_validate_flash_t), 
                GFP_KERNEL);
        if (dp->data == NULL) 
            return -ENOMEM;
    }

    /* We are only interested in the first 4K of the
     * candidate image */
    if ((*off >= VALIDATE_BUF_SIZE) || 
        (args_buf->status == VALIDATE_AUTH)) {
        *off += count;
        return count;
    }

    if (*off + count >= VALIDATE_BUF_SIZE)  {
        count = VALIDATE_BUF_SIZE - *off;
        args_buf->status = VALIDATE_READY;  
    } else {
        args_buf->status = VALIDATE_INCOMPLETE;
    }

    if (!access_ok(VERIFY_READ, buf, count)) {
        rc = -EFAULT;
        goto done;
    }
    if (copy_from_user(args_buf->buf + *off, buf, count)) {
        rc = -EFAULT;
        goto done;
    }

    *off += count;
    rc = count;
done:
    if (rc < 0) {
        kfree(dp->data);
        dp->data = NULL;
    }
    return rc;
}

static int validate_flash_release(struct inode *inode, struct file *file)
{
    struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
    struct rtas_validate_flash_t *args_buf;

    args_buf = (struct rtas_validate_flash_t *) dp->data;

    if (args_buf->status == VALIDATE_READY) {
        args_buf->buf_size = VALIDATE_BUF_SIZE;
        validate_flash(args_buf);
    }

    /* The matching atomic_inc was in rtas_excl_open() */
    atomic_dec(&dp->count);

    return 0;
}

static void rtas_flash_firmware(int reboot_type)
{
    unsigned long image_size;
    struct flash_block_list *f, *next, *flist;
    unsigned long rtas_block_list;
    int i, status, update_token;

    if (rtas_firmware_flash_list == NULL)
        return;     /* nothing to do */

    if (reboot_type != SYS_RESTART) {
        printk(KERN_ALERT "FLASH: firmware flash requires a reboot\n");
        printk(KERN_ALERT "FLASH: the firmware image will NOT be flashed\n");
        return;
    }

    update_token = rtas_token("ibm,update-flash-64-and-reboot");
    if (update_token == RTAS_UNKNOWN_SERVICE) {
        printk(KERN_ALERT "FLASH: ibm,update-flash-64-and-reboot "
               "is not available -- not a service partition?\n");
        printk(KERN_ALERT "FLASH: firmware will not be flashed\n");
        return;
    }

    /*
     * Just before starting the firmware flash, cancel the event scan work
     * to avoid any soft lockup issues.
     */
    rtas_cancel_event_scan();

    /*
     * NOTE: the "first" block must be under 4GB, so we create
     * an entry with no data blocks in the reserved buffer in
     * the kernel data segment.
     */
    spin_lock(&rtas_data_buf_lock);
    flist = (struct flash_block_list *)&rtas_data_buf[0];
    flist->num_blocks = 0;
    flist->next = rtas_firmware_flash_list;
    rtas_block_list = __pa(flist);
    if (rtas_block_list >= 4UL*1024*1024*1024) {
        printk(KERN_ALERT "FLASH: kernel bug...flash list header addr above 4GB\n");
        spin_unlock(&rtas_data_buf_lock);
        return;
    }

    printk(KERN_ALERT "FLASH: preparing saved firmware image for flash\n");
    /* Update the block_list in place. */
    rtas_firmware_flash_list = NULL; /* too hard to backout on error */
    image_size = 0;
    for (f = flist; f; f = next) {
        /* Translate data addrs to absolute */
        for (i = 0; i < f->num_blocks; i++) {
            f->blocks[i].data = (char *)__pa(f->blocks[i].data);
            image_size += f->blocks[i].length;
        }
        next = f->next;
        /* Don't translate NULL pointer for last entry */
        if (f->next)
            f->next = (struct flash_block_list *)__pa(f->next);
        else
            f->next = NULL;
        /* make num_blocks into the version/length field */
        f->num_blocks = (FLASH_BLOCK_LIST_VERSION << 56) | ((f->num_blocks+1)*16);
    }

    printk(KERN_ALERT "FLASH: flash image is %ld bytes\n", image_size);
    printk(KERN_ALERT "FLASH: performing flash and reboot\n");
    rtas_progress("Flashing        \n", 0x0);
    rtas_progress("Please Wait...  ", 0x0);
    printk(KERN_ALERT "FLASH: this will take several minutes.  Do not power off!\n");
    status = rtas_call(update_token, 1, 1, NULL, rtas_block_list);
    switch (status) {   /* should only get "bad" status */
        case 0:
        printk(KERN_ALERT "FLASH: success\n");
        break;
        case -1:
        printk(KERN_ALERT "FLASH: hardware error.  Firmware may not be not flashed\n");
        break;
        case -3:
        printk(KERN_ALERT "FLASH: image is corrupt or not correct for this platform.  Firmware not flashed\n");
        break;
        case -4:
        printk(KERN_ALERT "FLASH: flash failed when partially complete.  System may not reboot\n");
        break;
        default:
        printk(KERN_ALERT "FLASH: unknown flash return code %d\n", status);
        break;
    }
    spin_unlock(&rtas_data_buf_lock);
}

static void remove_flash_pde(struct proc_dir_entry *dp)
{
    if (dp) {
        kfree(dp->data);
        remove_proc_entry(dp->name, dp->parent);
    }
}

static int initialize_flash_pde_data(const char *rtas_call_name,
                     size_t buf_size,
                     struct proc_dir_entry *dp)
{
    int *status;
    int token;

    dp->data = kzalloc(buf_size, GFP_KERNEL);
    if (dp->data == NULL) {
        remove_flash_pde(dp);
        return -ENOMEM;
    }

    /*
     * This code assumes that the status int is the first member of the
     * struct 
     */
    status = (int *) dp->data;
    token = rtas_token(rtas_call_name);
    if (token == RTAS_UNKNOWN_SERVICE)
        *status = FLASH_AUTH;
    else
        *status = FLASH_NO_OP;

    return 0;
}

static struct proc_dir_entry *create_flash_pde(const char *filename,
                           const struct file_operations *fops)
{
    return proc_create(filename, S_IRUSR | S_IWUSR, NULL, fops);
}

static const struct file_operations rtas_flash_operations = {
    .owner      = THIS_MODULE,
    .read       = rtas_flash_read,
    .write      = rtas_flash_write,
    .open       = rtas_excl_open,
    .release    = rtas_flash_release,
    .llseek     = default_llseek,
};

static const struct file_operations manage_flash_operations = {
    .owner      = THIS_MODULE,
    .read       = manage_flash_read,
    .write      = manage_flash_write,
    .open       = rtas_excl_open,
    .release    = rtas_excl_release,
    .llseek     = default_llseek,
};

static const struct file_operations validate_flash_operations = {
    .owner      = THIS_MODULE,
    .read       = validate_flash_read,
    .write      = validate_flash_write,
    .open       = rtas_excl_open,
    .release    = validate_flash_release,
    .llseek     = default_llseek,
};

static int __init rtas_flash_init(void)
{
    int rc;

    if (rtas_token("ibm,update-flash-64-and-reboot") ==
               RTAS_UNKNOWN_SERVICE) {
        pr_info("rtas_flash: no firmware flash support\n");
        return 1;
    }

    firmware_flash_pde = create_flash_pde("powerpc/rtas/"
                          FIRMWARE_FLASH_NAME,
                          &rtas_flash_operations);
    if (firmware_flash_pde == NULL) {
        rc = -ENOMEM;
        goto cleanup;
    }

    rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
                       sizeof(struct rtas_update_flash_t), 
                       firmware_flash_pde);
    if (rc != 0)
        goto cleanup;

    firmware_update_pde = create_flash_pde("powerpc/rtas/"
                           FIRMWARE_UPDATE_NAME,
                           &rtas_flash_operations);
    if (firmware_update_pde == NULL) {
        rc = -ENOMEM;
        goto cleanup;
    }

    rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
                       sizeof(struct rtas_update_flash_t), 
                       firmware_update_pde);
    if (rc != 0)
        goto cleanup;

    validate_pde = create_flash_pde("powerpc/rtas/" VALIDATE_FLASH_NAME,
                        &validate_flash_operations);
    if (validate_pde == NULL) {
        rc = -ENOMEM;
        goto cleanup;
    }

    rc = initialize_flash_pde_data("ibm,validate-flash-image",
                               sizeof(struct rtas_validate_flash_t), 
                       validate_pde);
    if (rc != 0)
        goto cleanup;

    manage_pde = create_flash_pde("powerpc/rtas/" MANAGE_FLASH_NAME,
                      &manage_flash_operations);
    if (manage_pde == NULL) {
        rc = -ENOMEM;
        goto cleanup;
    }

    rc = initialize_flash_pde_data("ibm,manage-flash-image",
                           sizeof(struct rtas_manage_flash_t),
                       manage_pde);
    if (rc != 0)
        goto cleanup;

    rtas_flash_term_hook = rtas_flash_firmware;

    flash_block_cache = kmem_cache_create("rtas_flash_cache",
                RTAS_BLK_SIZE, RTAS_BLK_SIZE, 0,
                rtas_block_ctor);
    if (!flash_block_cache) {
        printk(KERN_ERR "%s: failed to create block cache\n",
                __func__);
        rc = -ENOMEM;
        goto cleanup;
    }
    return 0;

cleanup:
    remove_flash_pde(firmware_flash_pde);
    remove_flash_pde(firmware_update_pde);
    remove_flash_pde(validate_pde);
    remove_flash_pde(manage_pde);

    return rc;
}

static void __exit rtas_flash_cleanup(void)
{
    rtas_flash_term_hook = NULL;

    if (flash_block_cache)
        kmem_cache_destroy(flash_block_cache);

    remove_flash_pde(firmware_flash_pde);
    remove_flash_pde(firmware_update_pde);
    remove_flash_pde(validate_pde);
    remove_flash_pde(manage_pde);
}

module_init(rtas_flash_init);
module_exit(rtas_flash_cleanup);
MODULE_LICENSE("GPL");