[PATCH] extend physmap.c to support run-time adding partitions

Jun Sun
2003-10-23T01:27:05Z

[-- Attachment #1: Type: text/plain, Size: 707 bytes --]

While looking at drvers/mtd/maps directories, it becomes
obvious to me that many files are derived from physmap.c,
in order to add partition support or add their own
set_vpp() pointer, etc..

Such a need can be easily satisfied by extending physmap.c
a little.

In this patch, I like to introduce phsmap_add_partition()
function, which allows boards to add flash partitions
at run-time. (Note that you can still override this
hardcoded partition by using kernel command line)

In the patch I also showed how a board can make use of this
extension. Hopefully we can get rid of lots of files under
the maps directory. :)

Boards which need to set set_vpp pointer can do so easily
too.

Any comments?

Jun

[-- Attachment #2: mtd-physmap-support-partitions.patch --]
[-- Type: text/plain, Size: 5231 bytes --]

diff -Nru linux/arch/mips/mips-boards/malta/malta_setup.c.orig linux/arch/mips/mips-boards/malta/malta_setup.c
--- linux/arch/mips/mips-boards/malta/malta_setup.c.orig Fri Aug 1 10:50:18 2003
+++ linux/arch/mips/mips-boards/malta/malta_setup.c Wed Oct 22 17:26:24 2003
@@ -24,6 +24,7 @@
#ifdef CONFIG_BLK_DEV_IDE
#include <linux/ide.h>
#endif
+#include <linux/mtd/physmap.h>

#include <asm/cpu.h>
#include <asm/bootinfo.h>
@@ -166,6 +167,12 @@
conswitchp = &dummy_con;
#endif
#endif
+
+#if defined(CONFIG_MTD_PHYSMAP) && defined(CONFIG_MTD_PARTITIONS)
+ physmap_add_partition("YAMON", 0x100000, 0x0, MTD_WRITEABLE);
+ physmap_add_partition("User FS", 0x300000, 0x100000, 0);
+#endif
+
mips_reboot_setup();

board_time_init = mips_time_init;
diff -Nru linux/drivers/mtd/maps/physmap.c.orig linux/drivers/mtd/maps/physmap.c
--- linux/drivers/mtd/maps/physmap.c.orig Wed Jul 23 15:17:52 2003
+++ linux/drivers/mtd/maps/physmap.c Wed Oct 22 17:42:50 2003
@@ -2,6 +2,11 @@
* $Id: physmap.c,v 1.28 2003/05/28 15:53:43 dwmw2 Exp $
*
* Normal mappings of chips in physical memory
+ *
+ * Copyright (C) 2003 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * 031022 - [jsun] add physmap_add_partition()
*/

#include <linux/module.h>
@@ -23,7 +28,7 @@

struct map_info physmap_map = {
- .name = "Physically mapped flash",
+ .name = "phys_mapped_flash",
.size = WINDOW_SIZE,
.buswidth = BUSWIDTH,
.phys = WINDOW_ADDR,
@@ -33,35 +38,31 @@
static struct mtd_partition *mtd_parts;
static int mtd_parts_nb;

-static struct mtd_partition physmap_partitions[] = {
-#if 0
-/* Put your own partition definitions here */
- {
- .name = "bootROM",
- .size = 0x80000,
- .offset = 0,
- .mask_flags = MTD_WRITEABLE, /* force read-only */
- }, {
- .name = "zImage",
- .size = 0x100000,
- .offset = MTDPART_OFS_APPEND,
- .mask_flags = MTD_WRITEABLE, /* force read-only */
- }, {
- .name = "ramdisk.gz",
- .size = 0x300000,
- .offset = MTDPART_OFS_APPEND,
- .mask_flags = MTD_WRITEABLE, /* force read-only */
- }, {
- .name = "User FS",
- .size = MTDPART_SIZ_FULL,
- .offset = MTDPART_OFS_APPEND,
+#define NUM_PARTITIONS 4 /* random num which should be good enough */
+static struct mtd_partition physmap_partitions[NUM_PARTITIONS] __initdata = {};
+
+char *part_probes[] __initdata = {"cmdlinepart", "RedBoot", NULL};
+
+/*
+ * See include/linux/mtd/physmap.h file.
+ */
+static int part_index __initdata = 0;
+int __init physmap_add_partition(char *name, u32 size, u32 offset, u32 flags)
+{
+ if (part_index >= NUM_PARTITIONS) {
+ printk(KERN_ERR "physmap_add_partition() exceeds max partition table size (%d)\n", NUM_PARTITIONS);
+ return -1;
}
-#endif
-};

-#define NUM_PARTITIONS (sizeof(physmap_partitions)/sizeof(struct mtd_partition))
-const char *part_probes[] = {"cmdlinepart", "RedBoot", NULL};
+ physmap_partitions[part_index].name = name;
+ physmap_partitions[part_index].size = size;
+ physmap_partitions[part_index].offset = offset;
+ physmap_partitions[part_index].mask_flags = flags;
+
+ part_index++;

+ return 0;
+}
#endif /* CONFIG_MTD_PARTITIONS */

int __init init_physmap(void)
@@ -97,11 +98,11 @@
return 0;
}

- if (NUM_PARTITIONS != 0)
+ if (part_index != 0)
{
printk(KERN_NOTICE
"Using physmap partition definition\n");
- add_mtd_partitions (mymtd, physmap_partitions, NUM_PARTITIONS);
+ add_mtd_partitions (mymtd, physmap_partitions, part_index);
return 0;
}

diff -Nru linux/include/linux/mtd/physmap.h.orig linux/include/linux/mtd/physmap.h
--- linux/include/linux/mtd/physmap.h.orig Wed Oct 22 17:05:22 2003
+++ linux/include/linux/mtd/physmap.h Wed Oct 22 18:20:34 2003
@@ -0,0 +1,48 @@
+/*
+ * For boards with physically mapped flash and using
+ * drivers/mtd/maps/physmap.c mapping driver.
+ *
+ * Copyright (C) 2003 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * 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.
+ *
+ */
+
+#ifndef __LINUX_MTD_PHYSMAP__
+
+#include <linux/config.h>
+
+#if defined(CONFIG_MTD_PHYSMAP)
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+
+/*
+ * The map_info for physmap. Board can override size, buswidth, phys,
+ * (*set_vpp)(), etc in their initial setup routine.
+ */
+extern struct map_info physmap_map;
+
+#if defined(CONFIG_MTD_PARTITIONS)
+
+/*
+ * Machines that wish to do flash partition may want to call this function in
+ * their setup routine. Examples:
+ *
+ * physmap_add_partition("bootROM", 0x100000, 0, MTD_WRITEABLE);
+ * physmap_add_partition("User FS", 0x300000, 0x100000, 0)
+ *
+ * Note that one can always override this hard-coded partition with
+ * command line partition (you need to enable CONFIG_MTD_CMDLINE_PARTS).
+ */
+int physmap_add_partition(char *name, u32 size, u32 offset, u32 mask_flags);
+
+#endif /* defined(CONFIG_MTD_PARTITIONS) */
+#endif /* defined(CONFIG_MTD) */
+
+#endif /* __LINUX_MTD_PHYSMAP__ */
+