[Buildroot] [PATCH v2 15/17] board/olpc: document flashing the JFFS2 image
lkundrak at v3.sk
Wed Jun 17 10:49:23 UTC 2020
Signed-off-by: Lubomir Rintel <lkundrak at v3.sk>
board/olpc/readme.txt | 38 +++++++++++++++++++++++++++++---------
1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/board/olpc/readme.txt b/board/olpc/readme.txt
index 2ed44011f7..f04ad7037c 100644
@@ -9,10 +9,13 @@ Supported models
* OLPC XO-1
The original NS Geode based OLPC laptop, uses the x86 architecture.
+ Can be booted either from an internal MTD device formatted with JFFS2
+ or from a FAT or EXT4 partition on a SD card or a USB flash stick.
* OLPC XO-7.5
The ARM-based laptop. Needs a recent enough firmware to provide a good
- enough flattened device tree to the kernel.
+ enough flattened device tree to the kernel. Can be from a FAT or EXT4
+ partition on a internal eMMC, a SD card or a USB flash stick.
Configure and build
@@ -59,20 +62,37 @@ to update the firmware:
ok flash ext:\q4e00ja.rom \ Flash the "q4e00ja.rom" from the SD card
ok flash u:\q4e00ja.rom \ Flash the "q4e00ja.rom" from USB stick
-Create the bootable media
+Create the bootable SD card or USB flash stick
-When the build is finished, the resulting image file will be called
-"sdcard.img". It can be written directly to a SD-card or and USB flash stick.
+When the build is finished, an image file called "sdcard.img" will be created.
+It is suitable for writing directly to a SD card, USB flash stick or (on a
+XO-1.75) the internal eMMC flash.
-Please double check that you're using the right device (e.g. with "lsblk"
-command). Doing the following will DESTROY ALL DATA that's currently on the
+Before writing the image, please double check that you're using the right
+device (e.g. with "lsblk" command). Doing the following will DESTROY ALL DATA
+that's currently on the media.
# cat output/images/sdcard.img >/dev/<device>
+Flashing the JFFS2 image (XO-1 only)
+Unlike XO-1.75, the internal NAND flash on XO-1 is accessed without a FTL
+and needs a filesystem flash-friendly filesystem. A build configured for
+XO-1 creates a file named "root.jffs2" that can be written to it.
+One way to write it is from the Open Firmware prompt. First, partition
+and format a USB flash disk with a FAT file system and place the
+"root.jffs2" file onto it. Then power on the machine, enter the
+Open Firmware port by pressing the ESC key and run the following:
+ ok patch noop ?open-crcs copy-nand \ Disable CRC check
+ ok copy-nand u:\root.jffs2
Booting the machine
Once your machine is unlocked, it will automatically boot from your media
-wherever it will detect it attached to the USB bus or the SD card slot.
+wherever it will detect it attached to the USB bus or the SD card slot,
+otherwise it will proceed booting from the internal flash.
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