Didj U Boot Flashing Primer - Revision history

Jsujjava: missing brace

2011-04-16T00:03:25Z

missing brace

Jsujjava: categorize u-boot, howto

2011-04-16T00:02:55Z

categorize u-boot, howto

Chish: we must change size from 4000 to 8000 for LB2.0

2011-03-20T02:18:41Z

we must change size from 4000 to 8000 for LB2.0

SFlummox: /* Hardware Needed */ Added link to UART info --~~~~

2010-11-11T17:10:50Z

‎Hardware Needed: Added link to UART info --~~~~

Jburks: /* Step 1: Acquire a bootloader */

2010-04-12T03:21:57Z

‎Step 1: Acquire a bootloader

Jburks: /* Step 3a: Using SD/MMC */

2010-04-11T16:46:44Z

‎Step 3a: Using SD/MMC

Jburks at 20:13, 7 April 2010

2010-04-07T20:13:20Z

Jburks: /* nand erase */

2010-04-07T17:03:23Z

‎nand erase

Jburks at 17:03, 7 April 2010

2010-04-07T17:03:05Z

Jburks: Created page with 'This primer walks through the basics of the ''nand'' command in u-boot and shows how to use it to write a new bootloader. == Programs Needed == A serial terminal program, e.g. H…'

2010-04-07T16:51:56Z

Created page with 'This primer walks through the basics of the ''nand'' command in u-boot and shows how to use it to write a new bootloader. == Programs Needed == A serial terminal program, e.g. H…'

New page

This primer walks through the basics of the ''nand'' command in u-boot and shows how to use it to write a new bootloader.

== Programs Needed ==
A serial terminal program, e.g. Hyperterminal in windows or CuteCom in Linux.

== Hardware Needed ==
UART connection

SD adapter is useful but not required.

== Caution ==

'''This material can brick your Didj'''

While it is possible to still boot with a bad NAND, keep in mind that following the instructions in here there is a very slight, but real, possibility your Didj will never boot normally again. Follow these instructions at your own peril.

== The nand command ==

u-boot provides a single command for interfacing with your nand part. It is important to keep in mind when using these commands that ''''all values are given in hex, not decimal''' The general format of the nand command is:

<code>nand <command> [options]</code>

Some of the commands whose functions are understood are listed below.

=== nand dump ===

You can dump pages (2K of data) using the nand dump command. The format of the command is

<code>nand dump <page></code>

Here is an example of using nand dump:

LF1000 # nand dump 0
Page 00000000 dump:
04 d0 9f e5 01 00 00 eb 6c 0b 00 ea 00 80 22 00
34 c0 9f e5 01 30 a0 e3 00 30 8c e5 08 30 9c e5
02 0b a0 e3 04 e0 2d e5 80 30 83 e3 00 e0 a0 e3

=== nand read ===

You can read data from the nand into memory using the nand read command. The format of the command is

<code>nand read <address> <nand offset> <size></code>

Example:

LF1000 # nand read 1800000 0 800

NAND read: device 0 offset 0x0, size 0x800
2048 bytes read: OK
LF1000 # md 1800000 10
01800000: e59fd004 eb000001 ea000b6c 00228000 ........l.....".
01800010: e59fc034 e3a03001 e58c3000 e59c3008 4....0...0...0..
01800020: e3a00b02 e52de004 e3833080 e3a0e000 ......-..0......
01800030: e1a01000 e3a02b7e e58c3008 e58ce008 ....~+...0......

Comparison of this to the nand dump command above will show that these are the same data. Not that md has dumped the data in little endian format.

=== nand erase ===

'''Disclaimer:''' This will ''really'' erase a page of your nand. Make sure you think this through before doing it.

The nand erase command will reset a range of your nand to its unwritten state. In flash parts, such as Didj, this means all data within an erased page will become <code>0xFF</code>. The format of the command is:

<code>nand erase <offset> <size></code>

Example:

LF1000 # nand erase 0 4000

NAND erase: device 0 offset 0x0, size 0x4000
Erasing at 0x0 -- 800% complete.
OK
LF1000 # nand dump 0
Page 00000000 dump:
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

It is also important to understand that flash parts cannot erase less than one page. Either the whole page will be erased, or it will not. the size of your erasure should be a multiple of 0x800. In this case I have erased the first 16K of nand, which is where the bootstrap lives.

== To do ==

Need to document <code>nand write</code>.

← Older revision		Revision as of 00:03, 16 April 2011
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	At this point you should be ready to boot using your new bootloader. Remove the UART-boot jumper and type <code>reset</code> in u-boot and see what happens.		At this point you should be ready to boot using your new bootloader. Remove the UART-boot jumper and type <code>reset</code> in u-boot and see what happens.

−	[[Category:U-Boot]][Category:HOWTOs]]	+	[[Category:U-Boot]]
		+	[[Category:HOWTOs]]

← Older revision		Revision as of 00:02, 16 April 2011
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	At this point you should be ready to boot using your new bootloader. Remove the UART-boot jumper and type <code>reset</code> in u-boot and see what happens.		At this point you should be ready to boot using your new bootloader. Remove the UART-boot jumper and type <code>reset</code> in u-boot and see what happens.
		+
		+	[[Category:U-Boot]][Category:HOWTOs]]

@@ Line 112: / Line 112: @@
 ==== Step 1: Acquire a bootloader ====
-You will need to get the OpenDidj lightning-boot 1.4 (or later) NAND image. You can get the latest version from the [http://www.hackerfoundry.com/forums/viewtopic.php?f=4&t=23 OpenDidj lightning-boot hackerfoundry thread].
+You will need to get the OpenDidj lightning-boot 1.4 (or later) NAND image. You can get the latest version from the [http://www.hackerfoundry.com/forums/viewtopic.php?f=4&t=23 OpenDidj lightning-boot hackerfoundry thread](dead link).
 Run the following command on your linux box to double check which lightning-boot you have:
@@ Line 161: / Line 161: @@
 Use <code>nand erase</code> to erase the bootloader pages
-  LF1000 # nand erase 0 4000
+  LF1000 # nand erase 0 8000
-  NAND erase: device 0 offset 0x0, size 0x4000
+  NAND erase: device 0 offset 0x0, size 0x8000
-  Erasing at 0x0 -- 800% complete.
+  Erasing at 0x0 -- 400% complete.
   OK
@@ Line 173: / Line 173: @@
 Use <code>nand write</code> to write your new lightning-boot to flash.
-  LF1000 # nand write 1800000 0 4000
+  LF1000 # nand write 1800000 0 8000
-  NAND write: device 0 offset 0x0, size 0x4000
+  NAND write: device 0 offset 0x0, size 0x8000
 bytes written: OK
 You should use <code>nand dump 0</code> to verify that lightning-boot was written.

@@ Line 112: / Line 112: @@
 ==== Step 1: Acquire a bootloader ====
-You will need to get the OpenDidj lightning-boot 1.4 NAND image. Run the following command on your linux box to double check which lightning-boot you have:
+You will need to get the OpenDidj lightning-boot 1.4 (or later) NAND image. You can get the latest version from the [http://www.hackerfoundry.com/forums/viewtopic.php?f=4&t=23 OpenDidj lightning-boot hackerfoundry thread].
   # hexdump -C -n 16 lightning-boot.bin

@@ Line 134: / Line 134: @@
 ===== Step 3a: Using SD/MMC =====
-Initialize the MMC subsystem and load lightning-boot.bin into memory.
+Initialize the MMC subsystem...
   LF1000 # mmcinit
@@ Line 140: / Line 140: @@
   SD found : Size = 3866624 KBytes
   LF1000 # fatload mmc 0 1800000 lightning-boot.bin
   reading lightning-boot.bin

@@ Line 5: / Line 5: @@
 == Hardware Needed ==
-UART connection
+[[Didj Boot From UART | UART]] connection
 == Caution ==

@@ Line 6: / Line 6: @@
 == Hardware Needed ==
 UART connection
 == Caution ==
@@ Line 96: / Line 94: @@
 Note that you need to have the data you wish to write already in memory. In the example this data is 16Kbytes starting at physical address 0x1800000.
-== To do ==
+== Putting it all together ==
-Need to document putting it all together.
+At this point you should be ready to boot using your new bootloader. Remove the UART-boot jumper and type <code>reset</code> in u-boot and see what happens.

@@ Line 59: / Line 59: @@
 === nand erase ===
-'''Disclaimer:''' This will ''really'' erase a page of your nand. Make sure you think this through before doing it.
+'''Disclaimer:''' This will ''really'' erase one or more pages of your nand. Make sure you think this through before doing it.
 The nand erase command will reset a range of your nand to its unwritten state. In flash parts, such as Didj, this means all data within an erased page will become <code>0xFF</code>. The format of the command is:
@@ Line 78: / Line 78: @@
 It is also important to understand that flash parts cannot erase less than one page. Either the whole page will be erased, or it will not. the size of your erasure should be a multiple of 0x800. In this case I have erased the first 16K of nand, which is where the bootstrap lives.
 == To do ==
-Need to document <code>nand write</code>.
+Need to document putting it all together.