Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Parse RedBoot-style Flash Image System (FIS) tables and
 * produce a Linux partition array to match.
 *
 * Copyright © 2001      Red Hat UK Limited
 * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
 */
 
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/of.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/module.h>
 
struct fis_image_desc {
    unsigned char name[16];      // Null terminated name
    uint32_t	  flash_base;    // Address within FLASH of image
    uint32_t	  mem_base;      // Address in memory where it executes
    uint32_t	  size;          // Length of image
    uint32_t	  entry_point;   // Execution entry point
    uint32_t	  data_length;   // Length of actual data
    unsigned char _pad[256-(16+7*sizeof(uint32_t))];
    uint32_t	  desc_cksum;    // Checksum over image descriptor
    uint32_t	  file_cksum;    // Checksum over image data
};
 
struct fis_list {
<------>struct fis_image_desc *img;
<------>struct fis_list *next;
};
 
static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;
module_param(directory, int, 0);
 
static inline int redboot_checksum(struct fis_image_desc *img)
{
<------>/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
<------>return 1;
}
 
static void parse_redboot_of(struct mtd_info *master)
{
<------>struct device_node *np;
<------>struct device_node *npart;
<------>u32 dirblock;
<------>int ret;
 
<------>np = mtd_get_of_node(master);
<------>if (!np)
<------><------>return;
 
<------>npart = of_get_child_by_name(np, "partitions");
<------>if (!npart)
<------><------>return;
 
<------>ret = of_property_read_u32(npart, "fis-index-block", &dirblock);
<------>if (ret)
<------><------>return;
 
<------>/*
<------> * Assign the block found in the device tree to the local
<------> * directory block pointer.
<------> */
<------>directory = dirblock;
}
 
static int parse_redboot_partitions(struct mtd_info *master,
<------><------><------><------>    const struct mtd_partition **pparts,
<------><------><------><------>    struct mtd_part_parser_data *data)
{
<------>int nrparts = 0;
<------>struct fis_image_desc *buf;
<------>struct mtd_partition *parts;
<------>struct fis_list *fl = NULL, *tmp_fl;
<------>int ret, i;
<------>size_t retlen;
<------>char *names;
<------>char *nullname;
<------>int namelen = 0;
<------>int nulllen = 0;
<------>int numslots;
<------>unsigned long offset;
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
<------>static char nullstring[] = "unallocated";
#endif
 
<------>parse_redboot_of(master);
 
<------>if ( directory < 0 ) {
<------><------>offset = master->size + directory * master->erasesize;
<------><------>while (mtd_block_isbad(master, offset)) {
<------><------><------>if (!offset) {
<------><------><------>nogood:
<------><------><------><------>printk(KERN_NOTICE "Failed to find a non-bad block to check for RedBoot partition table\n");
<------><------><------><------>return -EIO;
<------><------><------>}
<------><------><------>offset -= master->erasesize;
<------><------>}
<------>} else {
<------><------>offset = directory * master->erasesize;
<------><------>while (mtd_block_isbad(master, offset)) {
<------><------><------>offset += master->erasesize;
<------><------><------>if (offset == master->size)
<------><------><------><------>goto nogood;
<------><------>}
<------>}
<------>buf = vmalloc(master->erasesize);
 
<------>if (!buf)
<------><------>return -ENOMEM;
 
<------>printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",
<------>       master->name, offset);
 
<------>ret = mtd_read(master, offset, master->erasesize, &retlen,
<------><------>       (void *)buf);
 
<------>if (ret)
<------><------>goto out;
 
<------>if (retlen != master->erasesize) {
<------><------>ret = -EIO;
<------><------>goto out;
<------>}
 
<------>numslots = (master->erasesize / sizeof(struct fis_image_desc));
<------>for (i = 0; i < numslots; i++) {
<------><------>if (!memcmp(buf[i].name, "FIS directory", 14)) {
<------><------><------>/* This is apparently the FIS directory entry for the
<------><------><------> * FIS directory itself.  The FIS directory size is
<------><------><------> * one erase block; if the buf[i].size field is
<------><------><------> * swab32(erasesize) then we know we are looking at
<------><------><------> * a byte swapped FIS directory - swap all the entries!
<------><------><------> * (NOTE: this is 'size' not 'data_length'; size is
<------><------><------> * the full size of the entry.)
<------><------><------> */
 
<------><------><------>/* RedBoot can combine the FIS directory and
<------><------><------>   config partitions into a single eraseblock;
<------><------><------>   we assume wrong-endian if either the swapped
<------><------><------>   'size' matches the eraseblock size precisely,
<------><------><------>   or if the swapped size actually fits in an
<------><------><------>   eraseblock while the unswapped size doesn't. */
<------><------><------>if (swab32(buf[i].size) == master->erasesize ||
<------><------><------>    (buf[i].size > master->erasesize
<------><------><------>     && swab32(buf[i].size) < master->erasesize)) {
<------><------><------><------>int j;
<------><------><------><------>/* Update numslots based on actual FIS directory size */
<------><------><------><------>numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc);
<------><------><------><------>for (j = 0; j < numslots; ++j) {
 
<------><------><------><------><------>/* A single 0xff denotes a deleted entry.
<------><------><------><------><------> * Two of them in a row is the end of the table.
<------><------><------><------><------> */
<------><------><------><------><------>if (buf[j].name[0] == 0xff) {
<------><------><------><------>  		if (buf[j].name[1] == 0xff) {
<------><------><------><------><------><------><------>break;
<------><------><------><------><------><------>} else {
<------><------><------><------><------><------><------>continue;
<------><------><------><------><------><------>}
<------><------><------><------><------>}
 
<------><------><------><------><------>/* The unsigned long fields were written with the
<------><------><------><------><------> * wrong byte sex, name and pad have no byte sex.
<------><------><------><------><------> */
<------><------><------><------><------>swab32s(&buf[j].flash_base);
<------><------><------><------><------>swab32s(&buf[j].mem_base);
<------><------><------><------><------>swab32s(&buf[j].size);
<------><------><------><------><------>swab32s(&buf[j].entry_point);
<------><------><------><------><------>swab32s(&buf[j].data_length);
<------><------><------><------><------>swab32s(&buf[j].desc_cksum);
<------><------><------><------><------>swab32s(&buf[j].file_cksum);
<------><------><------><------>}
<------><------><------>} else if (buf[i].size < master->erasesize) {
<------><------><------><------>/* Update numslots based on actual FIS directory size */
<------><------><------><------>numslots = buf[i].size / sizeof(struct fis_image_desc);
<------><------><------>}
<------><------><------>break;
<------><------>}
<------>}
<------>if (i == numslots) {
<------><------>/* Didn't find it */
<------><------>printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
<------><------>       master->name);
<------><------>ret = 0;
<------><------>goto out;
<------>}
 
<------>for (i = 0; i < numslots; i++) {
<------><------>struct fis_list *new_fl, **prev;
 
<------><------>if (buf[i].name[0] == 0xff) {
<------><------><------>if (buf[i].name[1] == 0xff) {
<------><------><------><------>break;
<------><------><------>} else {
<------><------><------><------>continue;
<------><------><------>}
<------><------>}
<------><------>if (!redboot_checksum(&buf[i]))
<------><------><------>break;
 
<------><------>new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
<------><------>namelen += strlen(buf[i].name)+1;
<------><------>if (!new_fl) {
<------><------><------>ret = -ENOMEM;
<------><------><------>goto out;
<------><------>}
<------><------>new_fl->img = &buf[i];
<------><------>if (data && data->origin)
<------><------><------>buf[i].flash_base -= data->origin;
<------><------>else
<------><------><------>buf[i].flash_base &= master->size-1;
 
<------><------>/* I'm sure the JFFS2 code has done me permanent damage.
<------><------> * I now think the following is _normal_
<------><------> */
<------><------>prev = &fl;
<------><------>while(*prev && (*prev)->img->flash_base < new_fl->img->flash_base)
<------><------><------>prev = &(*prev)->next;
<------><------>new_fl->next = *prev;
<------><------>*prev = new_fl;
 
<------><------>nrparts++;
<------>}
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
<------>if (fl->img->flash_base) {
<------><------>nrparts++;
<------><------>nulllen = sizeof(nullstring);
<------>}
 
<------>for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
<------><------>if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize <= tmp_fl->next->img->flash_base) {
<------><------><------>nrparts++;
<------><------><------>nulllen = sizeof(nullstring);
<------><------>}
<------>}
#endif
<------>parts = kzalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL);
 
<------>if (!parts) {
<------><------>ret = -ENOMEM;
<------><------>goto out;
<------>}
 
<------>nullname = (char *)&parts[nrparts];
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
<------>if (nulllen > 0) {
<------><------>strcpy(nullname, nullstring);
<------>}
#endif
<------>names = nullname + nulllen;
 
<------>i=0;
 
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
<------>if (fl->img->flash_base) {
<------>       parts[0].name = nullname;
<------>       parts[0].size = fl->img->flash_base;
<------>       parts[0].offset = 0;
<------><------>i++;
<------>}
#endif
<------>for ( ; i<nrparts; i++) {
<------><------>parts[i].size = fl->img->size;
<------><------>parts[i].offset = fl->img->flash_base;
<------><------>parts[i].name = names;
 
<------><------>strcpy(names, fl->img->name);
#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY
<------><------>if (!memcmp(names, "RedBoot", 8) ||
<------><------><------><------>!memcmp(names, "RedBoot config", 15) ||
<------><------><------><------>!memcmp(names, "FIS directory", 14)) {
<------><------><------>parts[i].mask_flags = MTD_WRITEABLE;
<------><------>}
#endif
<------><------>names += strlen(names)+1;
 
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
<------><------>if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize <= fl->next->img->flash_base) {
<------><------><------>i++;
<------><------><------>parts[i].offset = parts[i-1].size + parts[i-1].offset;
<------><------><------>parts[i].size = fl->next->img->flash_base - parts[i].offset;
<------><------><------>parts[i].name = nullname;
<------><------>}
#endif
<------><------>tmp_fl = fl;
<------><------>fl = fl->next;
<------><------>kfree(tmp_fl);
<------>}
<------>ret = nrparts;
<------>*pparts = parts;
 out:
<------>while (fl) {
<------><------>struct fis_list *old = fl;
<------><------>fl = fl->next;
<------><------>kfree(old);
<------>}
<------>vfree(buf);
<------>return ret;
}
 
static const struct of_device_id mtd_parser_redboot_of_match_table[] = {
<------>{ .compatible = "redboot-fis" },
<------>{},
};
MODULE_DEVICE_TABLE(of, mtd_parser_redboot_of_match_table);
 
static struct mtd_part_parser redboot_parser = {
<------>.parse_fn = parse_redboot_partitions,
<------>.name = "RedBoot",
<------>.of_match_table = mtd_parser_redboot_of_match_table,
};
module_mtd_part_parser(redboot_parser);
 
/* mtd parsers will request the module by parser name */
MODULE_ALIAS("RedBoot");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");