patch-2.4.20 linux-2.4.20/arch/ppc64/kernel/rtas_flash.c
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- Lines: 241
- Date:
Thu Nov 28 15:53:11 2002
- Orig file:
linux-2.4.19/arch/ppc64/kernel/rtas_flash.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -urN linux-2.4.19/arch/ppc64/kernel/rtas_flash.c linux-2.4.20/arch/ppc64/kernel/rtas_flash.c
@@ -0,0 +1,240 @@
+/*
+ * 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/ppc64/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/config.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <asm/rtas.h>
+
+#define MODULE_VERSION "1.0"
+#define MODULE_NAME "rtas_flash"
+
+#define FIRMWARE_FLASH_NAME "firmware_flash"
+
+/* Local copy of the flash block list.
+ * We only allow one open of the flash proc file and create this
+ * list as we go. This list will be put in the kernel's
+ * rtas_firmware_flash_list global var once it 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 on release.
+ */
+static struct flash_block_list *flist;
+static char *flash_msg;
+static int flash_possible;
+
+static int rtas_flash_open(struct inode *inode, struct file *file)
+{
+ if ((file->f_mode & FMODE_WRITE) && flash_possible) {
+ if (flist)
+ return -EBUSY;
+ flist = (struct flash_block_list *)get_free_page(GFP_KERNEL);
+ if (!flist)
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+/* 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;
+
+ flash_msg = NULL;
+ /* 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) {
+ flash_msg = "error: internal error null data\n";
+ return 0;
+ }
+ block_size = f->blocks[i].length;
+ if (block_size <= 0 || block_size > PAGE_SIZE) {
+ flash_msg = "error: internal error bad length\n";
+ return 0;
+ }
+ image_size += block_size;
+ }
+ }
+ if (image_size < (256 << 10)) {
+ if (image_size < 2)
+ flash_msg = NULL; /* allow "clear" of image */
+ else
+ flash_msg = "error: flash image short\n";
+ return 0;
+ }
+ printk(KERN_INFO "FLASH: flash image with %ld bytes stored for hardware flash on reboot\n", image_size);
+ return 1;
+}
+
+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++)
+ free_page((unsigned long)(f->blocks[i].data));
+ next = f->next;
+ free_page((unsigned long)f);
+ f = next;
+ }
+}
+
+static int rtas_flash_release(struct inode *inode, struct file *file)
+{
+ if (flist) {
+ /* Always clear saved list on a new attempt. */
+ if (rtas_firmware_flash_list.next) {
+ free_flash_list(rtas_firmware_flash_list.next);
+ rtas_firmware_flash_list.next = NULL;
+ }
+
+ if (flash_list_valid(flist))
+ rtas_firmware_flash_list.next = flist;
+ else
+ free_flash_list(flist);
+ flist = NULL;
+ }
+ return 0;
+}
+
+/* Reading the proc file will show status (not the firmware contents) */
+static ssize_t rtas_flash_read(struct file *file, char *buf,
+ size_t count, loff_t *ppos)
+{
+ int error;
+ char *msg;
+ int msglen;
+
+ if (!flash_possible) {
+ msg = "error: this partition does not have service authority\n";
+ } else if (flist) {
+ msg = "info: this file is busy for write by some process\n";
+ } else if (flash_msg) {
+ msg = flash_msg; /* message from last flash attempt */
+ } else if (rtas_firmware_flash_list.next) {
+ msg = "ready: firmware image ready for flash on reboot\n";
+ } else {
+ msg = "info: no firmware image for flash\n";
+ }
+ msglen = strlen(msg);
+ if (msglen > count)
+ msglen = count;
+
+ if (ppos && *ppos != 0)
+ return 0; /* be cheap */
+
+ error = verify_area(VERIFY_WRITE, buf, msglen);
+ if (error)
+ return -EINVAL;
+
+ copy_to_user(buf, msg, msglen);
+
+ if (ppos)
+ *ppos = msglen;
+ return msglen;
+}
+
+/* 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 *buffer,
+ size_t count, loff_t *off)
+{
+ size_t len = count;
+ char *p;
+ int next_free;
+ struct flash_block_list *fl = flist;
+
+ if (!flash_possible || len == 0)
+ return len; /* discard data */
+
+ 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 = (struct flash_block_list *)get_free_page(GFP_KERNEL);
+ if (!fl->next)
+ return -ENOMEM;
+ fl = fl->next;
+ next_free = 0;
+ }
+
+ if (len > PAGE_SIZE)
+ len = PAGE_SIZE;
+ p = (char *)get_free_page(GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+ if(copy_from_user(p, buffer, len)) {
+ free_page((unsigned long)p);
+ return -EFAULT;
+ }
+ fl->blocks[next_free].data = p;
+ fl->blocks[next_free].length = len;
+ fl->num_blocks++;
+
+ return len;
+}
+
+static struct file_operations rtas_flash_operations = {
+ read: rtas_flash_read,
+ write: rtas_flash_write,
+ open: rtas_flash_open,
+ release: rtas_flash_release,
+};
+
+
+int __init rtas_flash_init(void)
+{
+ struct proc_dir_entry *ent = NULL;
+
+ if (!rtas_proc_dir) {
+ printk(KERN_WARNING "rtas proc dir does not already exist");
+ return -ENOENT;
+ }
+
+ if (rtas_token("ibm,update-flash-64-and-reboot") != RTAS_UNKNOWN_SERVICE)
+ flash_possible = 1;
+
+ if ((ent = create_proc_entry(FIRMWARE_FLASH_NAME, S_IRUSR | S_IWUSR, rtas_proc_dir)) != NULL) {
+ ent->nlink = 1;
+ ent->proc_fops = &rtas_flash_operations;
+ ent->owner = THIS_MODULE;
+ }
+ return 0;
+}
+
+void __exit rtas_flash_cleanup(void)
+{
+ if (!rtas_proc_dir)
+ return;
+ remove_proc_entry(FIRMWARE_FLASH_NAME, rtas_proc_dir);
+}
+
+module_init(rtas_flash_init);
+module_exit(rtas_flash_cleanup);
+MODULE_LICENSE("GPL");
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