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-rw-r--r--drivers/mtd/parsers/afs.c395
1 files changed, 395 insertions, 0 deletions
diff --git a/drivers/mtd/parsers/afs.c b/drivers/mtd/parsers/afs.c
new file mode 100644
index 000000000..26116694c
--- /dev/null
+++ b/drivers/mtd/parsers/afs.c
@@ -0,0 +1,395 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*======================================================================
+
+ drivers/mtd/afs.c: ARM Flash Layout/Partitioning
+
+ Copyright © 2000 ARM Limited
+ Copyright (C) 2019 Linus Walleij
+
+
+ This is access code for flashes using ARM's flash partitioning
+ standards.
+
+======================================================================*/
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/init.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
+
+#define AFSV1_FOOTER_MAGIC 0xA0FFFF9F
+#define AFSV2_FOOTER_MAGIC1 0x464C5348 /* "FLSH" */
+#define AFSV2_FOOTER_MAGIC2 0x464F4F54 /* "FOOT" */
+
+struct footer_v1 {
+ u32 image_info_base; /* Address of first word of ImageFooter */
+ u32 image_start; /* Start of area reserved by this footer */
+ u32 signature; /* 'Magic' number proves it's a footer */
+ u32 type; /* Area type: ARM Image, SIB, customer */
+ u32 checksum; /* Just this structure */
+};
+
+struct image_info_v1 {
+ u32 bootFlags; /* Boot flags, compression etc. */
+ u32 imageNumber; /* Unique number, selects for boot etc. */
+ u32 loadAddress; /* Address program should be loaded to */
+ u32 length; /* Actual size of image */
+ u32 address; /* Image is executed from here */
+ char name[16]; /* Null terminated */
+ u32 headerBase; /* Flash Address of any stripped header */
+ u32 header_length; /* Length of header in memory */
+ u32 headerType; /* AIF, RLF, s-record etc. */
+ u32 checksum; /* Image checksum (inc. this struct) */
+};
+
+static u32 word_sum(void *words, int num)
+{
+ u32 *p = words;
+ u32 sum = 0;
+
+ while (num--)
+ sum += *p++;
+
+ return sum;
+}
+
+static u32 word_sum_v2(u32 *p, u32 num)
+{
+ u32 sum = 0;
+ int i;
+
+ for (i = 0; i < num; i++) {
+ u32 val;
+
+ val = p[i];
+ if (val > ~sum)
+ sum++;
+ sum += val;
+ }
+ return ~sum;
+}
+
+static bool afs_is_v1(struct mtd_info *mtd, u_int off)
+{
+ /* The magic is 12 bytes from the end of the erase block */
+ u_int ptr = off + mtd->erasesize - 12;
+ u32 magic;
+ size_t sz;
+ int ret;
+
+ ret = mtd_read(mtd, ptr, 4, &sz, (u_char *)&magic);
+ if (ret < 0) {
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return false;
+ }
+ if (ret >= 0 && sz != 4)
+ return false;
+
+ return (magic == AFSV1_FOOTER_MAGIC);
+}
+
+static bool afs_is_v2(struct mtd_info *mtd, u_int off)
+{
+ /* The magic is the 8 last bytes of the erase block */
+ u_int ptr = off + mtd->erasesize - 8;
+ u32 foot[2];
+ size_t sz;
+ int ret;
+
+ ret = mtd_read(mtd, ptr, 8, &sz, (u_char *)foot);
+ if (ret < 0) {
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return false;
+ }
+ if (ret >= 0 && sz != 8)
+ return false;
+
+ return (foot[0] == AFSV2_FOOTER_MAGIC1 &&
+ foot[1] == AFSV2_FOOTER_MAGIC2);
+}
+
+static int afs_parse_v1_partition(struct mtd_info *mtd,
+ u_int off, struct mtd_partition *part)
+{
+ struct footer_v1 fs;
+ struct image_info_v1 iis;
+ u_int mask;
+ /*
+ * Static checks cannot see that we bail out if we have an error
+ * reading the footer.
+ */
+ u_int iis_ptr;
+ u_int img_ptr;
+ u_int ptr;
+ size_t sz;
+ int ret;
+ int i;
+
+ /*
+ * This is the address mask; we use this to mask off out of
+ * range address bits.
+ */
+ mask = mtd->size - 1;
+
+ ptr = off + mtd->erasesize - sizeof(fs);
+ ret = mtd_read(mtd, ptr, sizeof(fs), &sz, (u_char *)&fs);
+ if (ret >= 0 && sz != sizeof(fs))
+ ret = -EINVAL;
+ if (ret < 0) {
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return ret;
+ }
+ /*
+ * Check the checksum.
+ */
+ if (word_sum(&fs, sizeof(fs) / sizeof(u32)) != 0xffffffff)
+ return -EINVAL;
+
+ /*
+ * Hide the SIB (System Information Block)
+ */
+ if (fs.type == 2)
+ return 0;
+
+ iis_ptr = fs.image_info_base & mask;
+ img_ptr = fs.image_start & mask;
+
+ /*
+ * Check the image info base. This can not
+ * be located after the footer structure.
+ */
+ if (iis_ptr >= ptr)
+ return 0;
+
+ /*
+ * Check the start of this image. The image
+ * data can not be located after this block.
+ */
+ if (img_ptr > off)
+ return 0;
+
+ /* Read the image info block */
+ memset(&iis, 0, sizeof(iis));
+ ret = mtd_read(mtd, iis_ptr, sizeof(iis), &sz, (u_char *)&iis);
+ if (ret < 0) {
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ iis_ptr, ret);
+ return -EINVAL;
+ }
+
+ if (sz != sizeof(iis))
+ return -EINVAL;
+
+ /*
+ * Validate the name - it must be NUL terminated.
+ */
+ for (i = 0; i < sizeof(iis.name); i++)
+ if (iis.name[i] == '\0')
+ break;
+ if (i > sizeof(iis.name))
+ return -EINVAL;
+
+ part->name = kstrdup(iis.name, GFP_KERNEL);
+ if (!part->name)
+ return -ENOMEM;
+
+ part->size = (iis.length + mtd->erasesize - 1) & ~(mtd->erasesize - 1);
+ part->offset = img_ptr;
+ part->mask_flags = 0;
+
+ printk(" mtd: at 0x%08x, %5lluKiB, %8u, %s\n",
+ img_ptr, part->size / 1024,
+ iis.imageNumber, part->name);
+
+ return 0;
+}
+
+static int afs_parse_v2_partition(struct mtd_info *mtd,
+ u_int off, struct mtd_partition *part)
+{
+ u_int ptr;
+ u32 footer[12];
+ u32 imginfo[36];
+ char *name;
+ u32 version;
+ u32 entrypoint;
+ u32 attributes;
+ u32 region_count;
+ u32 block_start;
+ u32 block_end;
+ u32 crc;
+ size_t sz;
+ int ret;
+ int i;
+ int pad = 0;
+
+ pr_debug("Parsing v2 partition @%08x-%08x\n",
+ off, off + mtd->erasesize);
+
+ /* First read the footer */
+ ptr = off + mtd->erasesize - sizeof(footer);
+ ret = mtd_read(mtd, ptr, sizeof(footer), &sz, (u_char *)footer);
+ if ((ret < 0) || (ret >= 0 && sz != sizeof(footer))) {
+ pr_err("AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return -EIO;
+ }
+ name = (char *) &footer[0];
+ version = footer[9];
+ ptr = off + mtd->erasesize - sizeof(footer) - footer[8];
+
+ pr_debug("found image \"%s\", version %08x, info @%08x\n",
+ name, version, ptr);
+
+ /* Then read the image information */
+ ret = mtd_read(mtd, ptr, sizeof(imginfo), &sz, (u_char *)imginfo);
+ if ((ret < 0) || (ret >= 0 && sz != sizeof(imginfo))) {
+ pr_err("AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return -EIO;
+ }
+
+ /* 32bit platforms have 4 bytes padding */
+ crc = word_sum_v2(&imginfo[1], 34);
+ if (!crc) {
+ pr_debug("Padding 1 word (4 bytes)\n");
+ pad = 1;
+ } else {
+ /* 64bit platforms have 8 bytes padding */
+ crc = word_sum_v2(&imginfo[2], 34);
+ if (!crc) {
+ pr_debug("Padding 2 words (8 bytes)\n");
+ pad = 2;
+ }
+ }
+ if (crc) {
+ pr_err("AFS: bad checksum on v2 image info: %08x\n", crc);
+ return -EINVAL;
+ }
+ entrypoint = imginfo[pad];
+ attributes = imginfo[pad+1];
+ region_count = imginfo[pad+2];
+ block_start = imginfo[20];
+ block_end = imginfo[21];
+
+ pr_debug("image entry=%08x, attr=%08x, regions=%08x, "
+ "bs=%08x, be=%08x\n",
+ entrypoint, attributes, region_count,
+ block_start, block_end);
+
+ for (i = 0; i < region_count; i++) {
+ u32 region_load_addr = imginfo[pad + 3 + i*4];
+ u32 region_size = imginfo[pad + 4 + i*4];
+ u32 region_offset = imginfo[pad + 5 + i*4];
+ u32 region_start;
+ u32 region_end;
+
+ pr_debug(" region %d: address: %08x, size: %08x, "
+ "offset: %08x\n",
+ i,
+ region_load_addr,
+ region_size,
+ region_offset);
+
+ region_start = off + region_offset;
+ region_end = region_start + region_size;
+ /* Align partition to end of erase block */
+ region_end += (mtd->erasesize - 1);
+ region_end &= ~(mtd->erasesize -1);
+ pr_debug(" partition start = %08x, partition end = %08x\n",
+ region_start, region_end);
+
+ /* Create one partition per region */
+ part->name = kstrdup(name, GFP_KERNEL);
+ if (!part->name)
+ return -ENOMEM;
+ part->offset = region_start;
+ part->size = region_end - region_start;
+ part->mask_flags = 0;
+ }
+
+ return 0;
+}
+
+static int parse_afs_partitions(struct mtd_info *mtd,
+ const struct mtd_partition **pparts,
+ struct mtd_part_parser_data *data)
+{
+ struct mtd_partition *parts;
+ u_int off, sz;
+ int ret = 0;
+ int i;
+
+ /* Count the partitions by looping over all erase blocks */
+ for (i = off = sz = 0; off < mtd->size; off += mtd->erasesize) {
+ if (afs_is_v1(mtd, off)) {
+ sz += sizeof(struct mtd_partition);
+ i += 1;
+ }
+ if (afs_is_v2(mtd, off)) {
+ sz += sizeof(struct mtd_partition);
+ i += 1;
+ }
+ }
+
+ if (!i)
+ return 0;
+
+ parts = kzalloc(sz, GFP_KERNEL);
+ if (!parts)
+ return -ENOMEM;
+
+ /*
+ * Identify the partitions
+ */
+ for (i = off = 0; off < mtd->size; off += mtd->erasesize) {
+ if (afs_is_v1(mtd, off)) {
+ ret = afs_parse_v1_partition(mtd, off, &parts[i]);
+ if (ret)
+ goto out_free_parts;
+ i++;
+ }
+ if (afs_is_v2(mtd, off)) {
+ ret = afs_parse_v2_partition(mtd, off, &parts[i]);
+ if (ret)
+ goto out_free_parts;
+ i++;
+ }
+ }
+
+ *pparts = parts;
+ return i;
+
+out_free_parts:
+ while (--i >= 0)
+ kfree(parts[i].name);
+ kfree(parts);
+ *pparts = NULL;
+ return ret;
+}
+
+static const struct of_device_id mtd_parser_afs_of_match_table[] = {
+ { .compatible = "arm,arm-firmware-suite" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtd_parser_afs_of_match_table);
+
+static struct mtd_part_parser afs_parser = {
+ .parse_fn = parse_afs_partitions,
+ .name = "afs",
+ .of_match_table = mtd_parser_afs_of_match_table,
+};
+module_mtd_part_parser(afs_parser);
+
+MODULE_AUTHOR("ARM Ltd");
+MODULE_DESCRIPTION("ARM Firmware Suite partition parser");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 08:38:55 +0000