Flash ROM

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Revision as of 03:23, 7 July 2006 (view source) Jkk (Talk) m (flash ROM -> Flash ROM) ← Older edit		Latest revision as of 21:05, 30 April 2007 (view source) Mathew (Talk)
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-	Currently, all Kuroboxes have a 4MB Flash ROM. The Flash ROM houses vital information such as the Linux kernel for standard operation and emergency mode, as well as the code for booting into the kernel. The contents are layed out in different ways depending on which Kernel you are using. Flash ROM chip data can be updated, deleted, or reprogrammed through the Linux console or via the [[Add Jtag Port|optional JTAG port]].	+	[[Image:Fujitsu_29PL32TM-90PFTN.jpg|thumb|right|The Kurobox's Flash ROM chip]]
-	==Stock 2.4.x Kernel==	+	Currently, the Kuroboxes all use a Fujitsu 29PL32TM-90PFTN 4MB Flash ROM chip. The Flash ROM houses vital information such as the Linux kernel for standard operation and emergency mode, as well as the code for booting into the kernel. The contents are layed out in different ways depending on which Kernel you are using. Flash ROM chip data can be updated, deleted, or reprogrammed through the Linux console or via the [[Add Jtag Port|optional JTAG port]].
		+
		+	==Reprogramming the Flash ROM==
		+	Please be very careful when reprogramming your Flash ROM. Overwriting or erasing your Flash ROM can turn your Kurobox into a [[brick]].
		+
		+	The interest in reprogramming the Flash comes mostly from the desire to run a custom kernel than the stock one that is packaged with the Kurobox. This is possible by overwriting the original bootcode with [[HOWTO U-Boot|U-Boot]].
		+
		+	==Flash ROM Layouts==
		+	===Stock 2.4.x Kernel===
	{| border="1" cellpadding="3"		{| border="1" cellpadding="3"
	! device !! start !! end !! size !! contents		! device !! start !! end !! size !! contents
Line 14:		Line 22:
	|}		|}
-		+	===Patched 2.6.x Kernel v1===
-	==Patched 2.6.x Kernel v1==	+
	{| border="1" cellpadding="3"		{| border="1" cellpadding="3"
	! device !! size !! erasesize !! name		! device !! size !! erasesize !! name
Line 32:		Line 39:
	|}		|}
-		+	===Patched 2.6.x Kernel v2===
-	==Patched 2.6.x Kernel v2==	+
	{| border="1" cellpadding="3"		{| border="1" cellpadding="3"
	! device !! size !! erasesize !! name		! device !! size !! erasesize !! name
Line 47:		Line 53:
	|mtd4: || 00080000 || 00010000 || "mtd_conf"		|mtd4: || 00080000 || 00010000 || "mtd_conf"
	|}		|}
		+
		+
		+	==Checking the layout (with kernel 2.6.x)==
		+	Simply type:
		+	cat /proc/mtd
		+
		+	==Additional Flash Chip?==
		+	There has been some discussion going on at the Kurobox forums, regarding the possibility of adding an additional Flash chip.
		+	* [http://www.kurobox.com/forums/viewtopic.php?t=898 Original thread]
		+
		+	==Datasheet==
		+	You can get the flash chip datasheet [http://www.kurobox.com/downloads/Hardware/kuroflash.pdf here.]
		+
		+	[[Category:Hardware]]
		+	[[Category:JTAG]]

---

Latest revision as of 21:05, 30 April 2007

Currently, the Kuroboxes all use a Fujitsu 29PL32TM-90PFTN 4MB Flash ROM chip. The Flash ROM houses vital information such as the Linux kernel for standard operation and emergency mode, as well as the code for booting into the kernel. The contents are layed out in different ways depending on which Kernel you are using. Flash ROM chip data can be updated, deleted, or reprogrammed through the Linux console or via the optional JTAG port.

Contents 1 Reprogramming the Flash ROM 2 Flash ROM Layouts 2.1 Stock 2.4.x Kernel 2.2 Patched 2.6.x Kernel v1 2.3 Patched 2.6.x Kernel v2 3 Checking the layout (with kernel 2.6.x) 4 Additional Flash Chip? 5 Datasheet

Reprogramming the Flash ROM

Please be very careful when reprogramming your Flash ROM. Overwriting or erasing your Flash ROM can turn your Kurobox into a brick.

The interest in reprogramming the Flash comes mostly from the desire to run a custom kernel than the stock one that is packaged with the Kurobox. This is possible by overwriting the original bootcode with U-Boot.

Flash ROM Layouts

Stock 2.4.x Kernel

device	start	end	size	contents
/dev/fl0	0xFFF80000	0x080000	512 K	Empty
/dev/fl1	0xFFC00000	0x300000	3 MB	Linux/initrd
/dev/fl2	0xFFF00000	0x070000	448 K	bootcode.bin
/dev/fl3	0xFFF70000	0x010000	64K	HDD status (OKOKOK)

Patched 2.6.x Kernel v1

device	size	erasesize	name
mtd0:	00300000	00010000	"mtd_firmimg"
mtd1:	00070000	00010000	"mtd_bootcode"
mtd2:	00010000	00010000	"mtd_status"
mtd3:	00080000	00010000	"mtd_conf"
mtd4:	00400000	00010000	"mtd_allflash"
mtd5:	000f0000	00010000	"mtd_data"

Patched 2.6.x Kernel v2

device	size	erasesize	name
mtd0:	00400000	00010000	"mtd_allflash"
mtd1:	00300000	00010000	"mtd_firmimg"
mtd2:	00070000	00010000	"mtd_bootcode"
mtd3:	00010000	00010000	"mtd_status"
mtd4:	00080000	00010000	"mtd_conf"

Checking the layout (with kernel 2.6.x)

Simply type:

cat /proc/mtd

Additional Flash Chip?

There has been some discussion going on at the Kurobox forums, regarding the possibility of adding an additional Flash chip.

• Original thread

Datasheet

You can get the flash chip datasheet here.