mtd: afs: Move AFS partition parser to parsers subdir

This moves the AFS (ARM Firmware Suite) partition parser
for NOR flash down into the parsers subdirectory.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

3 files changed, 283 insertions, 0 deletions

diff --git a/drivers/mtd/parsers/Kconfig b/drivers/mtd/parsers/Kconfig
index c8be3f1507ca..bc201327dda0 100644
--- a/drivers/mtd/parsers/Kconfig
+++ b/drivers/mtd/parsers/Kconfig
@@ -9,6 +9,22 @@ config MTD_PARSER_IMAGETAG
 	  This driver adds support for parsing a partition with an Image Tag
 	  header and creates up to two partitions, kernel and rootfs.
 
+config MTD_AFS_PARTS
+	tristate "ARM Firmware Suite partition parsing"
+	depends on (ARM || ARM64)
+	help
+	  The ARM Firmware Suite allows the user to divide flash devices into
+	  multiple 'images'. Each such image has a header containing its name
+	  and offset/size etc.
+
+	  If you need code which can detect and parse these tables, and
+	  register MTD 'partitions' corresponding to each image detected,
+	  enable this option.
+
+	  You will still need the parsing functions to be called by the driver
+	  for your particular device. It won't happen automatically. The
+	  'physmap' map driver (CONFIG_MTD_PHYSMAP) does this, for example.
+
 config MTD_PARSER_TRX
 	tristate "Parser for TRX format partitions"
 	depends on MTD && (BCM47XX || ARCH_BCM_5301X || COMPILE_TEST)
diff --git a/drivers/mtd/parsers/Makefile b/drivers/mtd/parsers/Makefile
index 3860c4464c63..cddc8f35a856 100644
--- a/drivers/mtd/parsers/Makefile
+++ b/drivers/mtd/parsers/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_MTD_PARSER_IMAGETAG)	+= parser_imagetag.o
+obj-$(CONFIG_MTD_AFS_PARTS)		+= afs.o
 obj-$(CONFIG_MTD_PARSER_TRX)		+= parser_trx.o
 obj-$(CONFIG_MTD_SHARPSL_PARTS)		+= sharpslpart.o
 obj-$(CONFIG_MTD_REDBOOT_PARTS)		+= redboot.o
diff --git a/drivers/mtd/parsers/afs.c b/drivers/mtd/parsers/afs.c
new file mode 100644
index 000000000000..d61b7edfc938
--- /dev/null
+++ b/drivers/mtd/parsers/afs.c
@@ -0,0 +1,266 @@
+/*======================================================================
+
+    drivers/mtd/afs.c: ARM Flash Layout/Partitioning
+
+    Copyright © 2000 ARM Limited
+
+   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.
+
+   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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+   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
+
+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 int
+afs_read_footer_v1(struct mtd_info *mtd, u_int *img_start, u_int *iis_start,
+		   u_int off, u_int mask)
+{
+	struct footer_v1 fs;
+	u_int ptr = off + mtd->erasesize - sizeof(fs);
+	size_t sz;
+	int ret;
+
+	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;
+	}
+
+	/*
+	 * Does it contain the magic number?
+	 */
+	if (fs.signature != AFSV1_FOOTER_MAGIC)
+		return 0;
+
+	/*
+	 * Check the checksum.
+	 */
+	if (word_sum(&fs, sizeof(fs) / sizeof(u32)) != 0xffffffff)
+		return 0;
+
+	/*
+	 * Don't touch the SIB.
+	 */
+	if (fs.type == 2)
+		return 0;
+
+	*iis_start = fs.image_info_base & mask;
+	*img_start = fs.image_start & mask;
+
+	/*
+	 * Check the image info base.  This can not
+	 * be located after the footer structure.
+	 */
+	if (*iis_start >= ptr)
+		return 0;
+
+	/*
+	 * Check the start of this image.  The image
+	 * data can not be located after this block.
+	 */
+	if (*img_start > off)
+		return 0;
+
+	return 1;
+}
+
+static int
+afs_read_iis_v1(struct mtd_info *mtd, struct image_info_v1 *iis, u_int ptr)
+{
+	size_t sz;
+	int ret, i;
+
+	memset(iis, 0, sizeof(*iis));
+	ret = mtd_read(mtd, ptr, sizeof(*iis), &sz, (u_char *)iis);
+	if (ret < 0)
+		goto failed;
+
+	if (sz != sizeof(*iis)) {
+		ret = -EINVAL;
+		goto failed;
+	}
+
+	ret = 0;
+
+	/*
+	 * 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))
+		ret = 1;
+
+	return ret;
+
+ failed:
+	printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+		ptr, ret);
+	return ret;
+}
+
+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 mask, off, idx, sz;
+	int ret = 0;
+	char *str;
+
+	/*
+	 * This is the address mask; we use this to mask off out of
+	 * range address bits.
+	 */
+	mask = mtd->size - 1;
+
+	/*
+	 * First, calculate the size of the array we need for the
+	 * partition information.  We include in this the size of
+	 * the strings.
+	 */
+	for (idx = off = sz = 0; off < mtd->size; off += mtd->erasesize) {
+		struct image_info_v1 iis;
+		u_int iis_ptr, img_ptr;
+
+		ret = afs_read_footer_v1(mtd, &img_ptr, &iis_ptr, off, mask);
+		if (ret < 0)
+			break;
+		if (ret) {
+			ret = afs_read_iis_v1(mtd, &iis, iis_ptr);
+			if (ret < 0)
+				break;
+			if (ret == 0)
+				continue;
+
+			sz += sizeof(struct mtd_partition);
+			sz += strlen(iis.name) + 1;
+			idx += 1;
+		}
+	}
+
+	if (!sz)
+		return ret;
+
+	parts = kzalloc(sz, GFP_KERNEL);
+	if (!parts)
+		return -ENOMEM;
+
+	str = (char *)(parts + idx);
+
+	/*
+	 * Identify the partitions
+	 */
+	for (idx = off = 0; off < mtd->size; off += mtd->erasesize) {
+		struct image_info_v1 iis;
+		u_int iis_ptr, img_ptr;
+
+		/* Read the footer. */
+		ret = afs_read_footer_v1(mtd, &img_ptr, &iis_ptr, off, mask);
+		if (ret < 0)
+			break;
+		if (ret == 0)
+			continue;
+
+		/* Read the image info block */
+		ret = afs_read_iis_v1(mtd, &iis, iis_ptr);
+		if (ret < 0)
+			break;
+		if (ret == 0)
+			continue;
+
+		strcpy(str, iis.name);
+
+		parts[idx].name		= str;
+		parts[idx].size		= (iis.length + mtd->erasesize - 1) & ~(mtd->erasesize - 1);
+		parts[idx].offset	= img_ptr;
+		parts[idx].mask_flags	= 0;
+
+		printk("  mtd%d: at 0x%08x, %5lluKiB, %8u, %s\n",
+			idx, img_ptr, parts[idx].size / 1024,
+			iis.imageNumber, str);
+
+		idx += 1;
+		str = str + strlen(iis.name) + 1;
+	}
+
+	if (!idx) {
+		kfree(parts);
+		parts = NULL;
+	}
+
+	*pparts = parts;
+	return idx ? idx : ret;
+}
+
+static struct mtd_part_parser afs_parser = {
+	.parse_fn = parse_afs_partitions,
+	.name = "afs",
+};
+module_mtd_part_parser(afs_parser);
+
+MODULE_AUTHOR("ARM Ltd");
+MODULE_DESCRIPTION("ARM Firmware Suite partition parser");
+MODULE_LICENSE("GPL");