detect AC49x flash partitions

Signed-off-by: Daniel Golle <dgolle@allnet.de>
Signed-off-by: Florian Fainelli <florian@openwrt.org>

SVN-Revision: 34146

1 files changed, 220 insertions, 0 deletions

diff --git a/target/linux/ar7/files/drivers/mtd/ac49xpart.c b/target/linux/ar7/files/drivers/mtd/ac49xpart.c
new file mode 100644
index 0000000..1f937f0
--- /dev/null
+++ b/target/linux/ar7/files/drivers/mtd/ac49xpart.c
@@ -0,0 +1,220 @@
+/*
+ * AudioCodes AC49x PSPBoot-based flash partition table
+ * Copyright 2012 Daniel Golle <daniel.golle@gmail.com>
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/bootmem.h>
+#include <linux/magic.h>
+#include <linux/module.h>
+
+#include <asm/mach-ar7/prom.h>
+
+#define AC49X_MAXENVPARTS	8
+
+#define AC49X_PARTTYPE_LOADER	0
+#define AC49X_PARTTYPE_BOOTENV	1
+#define AC49X_PARTTYPE_LINUX	2
+#define AC49X_PARTTYPE_ROOTFS	3
+#define AC49X_PARTTYPE_UNKNOWN	4
+#define AC49X_NUM_PARTTYPES	5
+
+#define AC49X_FLASH_ADDRMASK	0x00FFFFFF
+
+#define AC49X_LOADER_MAGIC	0x40809000
+#define AC49X_LINUX_MAGIC	0x464c457f /*  ELF */
+#define AC49X_BOOTENV_MAGIC	0x4578614d /* MaxE */
+
+#define ROOTFS_MIN_OFFSET	0xC0000
+
+int parse_partvar(const unsigned char *partvar, struct mtd_partition *part)
+{
+	unsigned int partstart, partend;
+	unsigned int pnum;
+
+	pnum = sscanf(partvar, "0x%x,0x%x", &partstart, &partend);
+	if (pnum != 2)
+		return 1;
+
+	part->offset = partstart & AC49X_FLASH_ADDRMASK;
+	part->size = partend - partstart;
+
+	return 0;
+}
+
+int detect_parttype(struct mtd_info *master, struct mtd_partition part)
+{
+	unsigned int magic;
+	size_t len;
+
+	if (part.size < 4)
+		return -1;
+
+	mtd_read(master, part.offset, sizeof(magic), &len,
+		 (uint8_t *)&magic);
+
+	if (len != sizeof(magic))
+		return -1;
+
+	switch (magic) {
+	case AC49X_LOADER_MAGIC:
+		return AC49X_PARTTYPE_LOADER;
+	case AC49X_LINUX_MAGIC:
+		return AC49X_PARTTYPE_LINUX;
+	case SQUASHFS_MAGIC:
+	case CRAMFS_MAGIC:
+	case CRAMFS_MAGIC_WEND:
+		return AC49X_PARTTYPE_ROOTFS;
+	case AC49X_BOOTENV_MAGIC:
+		return AC49X_PARTTYPE_BOOTENV;
+	default:
+		switch (magic & 0xFF) {
+		case JFFS2_SUPER_MAGIC:
+			return AC49X_PARTTYPE_ROOTFS;
+		}
+		switch (magic >> 8) {
+		case JFFS2_SUPER_MAGIC:
+			return AC49X_PARTTYPE_ROOTFS;
+		}
+		return AC49X_PARTTYPE_UNKNOWN;
+	}
+}
+
+const char *partnames[] = {
+	"loader",
+	"config",
+	"linux",
+	"rootfs",
+	"data"
+};
+
+void gen_partname(unsigned int type,
+		  unsigned int *typenumeration,
+		  struct mtd_partition *part)
+{
+	char *s  = kzalloc(sizeof(char) * 8, GFP_KERNEL);
+
+	(typenumeration[type])++;
+	if (typenumeration[type] == 1)
+		sprintf(s, "%s", partnames[type]);
+	else
+		sprintf(s, "%s%d", partnames[type], typenumeration[type]);
+
+	part->name = s;
+}
+
+static int create_mtd_partitions(struct mtd_info *master,
+				 struct mtd_partition **pparts,
+				 struct mtd_part_parser_data *data)
+{
+	unsigned int envpartnum = 0, linuxpartnum = 0;
+	unsigned int typenumeration[5] = { 0, 0, 0, 0, 0 };
+	unsigned char evn[5];
+	const unsigned char *partvar = NULL;
+
+	struct mtd_partition *ac49x_parts;
+
+	ac49x_parts = kzalloc(sizeof(*ac49x_parts) * AC49X_MAXENVPARTS,
+				GFP_KERNEL);
+
+	if (!ac49x_parts)
+		return -ENOMEM;
+
+	linuxpartnum = 0;
+	for (envpartnum = 0; envpartnum < AC49X_MAXENVPARTS; envpartnum++) {
+		struct mtd_partition parsepart;
+		unsigned int offset, size, type;
+		int err;
+		sprintf(evn, "mtd%d", envpartnum);
+		partvar = prom_getenv(evn);
+		if (!partvar)
+			continue;
+		err = parse_partvar(partvar, &parsepart);
+		if (err)
+			continue;
+		offset = parsepart.offset;
+		size = parsepart.size;
+		type = detect_parttype(master, parsepart);
+		gen_partname(type, typenumeration, &parsepart);
+		/* protect loader */
+		if (type == AC49X_PARTTYPE_LOADER)
+			parsepart.mask_flags = MTD_WRITEABLE;
+		else
+			parsepart.mask_flags = 0;
+
+		memcpy(&(ac49x_parts[linuxpartnum]), &parsepart,
+			sizeof(struct mtd_partition));
+
+		/* scan for contained rootfs */
+		if (type == AC49X_PARTTYPE_LINUX) {
+			parsepart.offset += ROOTFS_MIN_OFFSET &
+						~(master->erasesize - 1);
+			parsepart.size -= ROOTFS_MIN_OFFSET &
+						~(master->erasesize - 1);
+			do {
+				unsigned int size, offset;
+				size = parsepart.size;
+				offset = parsepart.offset;
+
+				type = detect_parttype(master, parsepart);
+				if (type == AC49X_PARTTYPE_ROOTFS) {
+					gen_partname(type, typenumeration,
+							&parsepart);
+					printk(KERN_INFO
+						"%s %s: 0x%08x@0x%08x\n",
+						"detected sub-partition",
+						parsepart.name,
+						(unsigned int)parsepart.size,
+						(unsigned int)parsepart.offset);
+					linuxpartnum++;
+					memcpy(&(ac49x_parts[linuxpartnum]),
+						&parsepart,
+						sizeof(struct mtd_partition));
+					break;
+				}
+				parsepart.offset += master->erasesize;
+				parsepart.size -= master->erasesize;
+			} while (parsepart.size >= master->erasesize);
+		}
+		linuxpartnum++;
+	}
+
+	*pparts = ac49x_parts;
+	return linuxpartnum;
+}
+
+static struct mtd_part_parser ac49x_parser = {
+	.owner = THIS_MODULE,
+	.parse_fn = create_mtd_partitions,
+	.name = "ac49xpart",
+};
+
+static int __init ac49x_parser_init(void)
+{
+	return register_mtd_parser(&ac49x_parser);
+}
+
+module_init(ac49x_parser_init);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Golle <daniel.golle@gmail.com>");
+MODULE_DESCRIPTION("MTD partitioning for AudioCodes AC49x");