Difference between revisions of "Prepare a bootable MicroSD Card"

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<div style="text-align: left;">First of all it is important to detect which device is our microSD Card. In order to do that we can follow this instructions in a Linux terminal:</div>
 
<div style="text-align: left;">First of all it is important to detect which device is our microSD Card. In order to do that we can follow this instructions in a Linux terminal:</div>
 
<div style="text-align: left; padding-left: 30px;">'''1-''' Clean the ''dmesg'' information:</div>
 
<div style="text-align: left; padding-left: 30px;">'''1-''' Clean the ''dmesg'' information:</div>
  sudo dmesg -c<div style="text-align: left; padding-left: 30px;">'''2- '''Insert the microSD Card and show the ''dmesg'' information:</div>
+
  sudo dmesg -c<div style="text-align: left; padding-left: 30px;">'''2-''' Insert the microSD Card and show the ''dmesg'' information:</div>
 
  dmesg<div style="text-align: left;">The result have to be similar to this:</div>
 
  dmesg<div style="text-align: left;">The result have to be similar to this:</div>
 
+
[[File:SD1_.png]]
  
 
<div style="text-align: left;">We can see the name of our device in the system: '''/dev/sdX''' where X is the character assigned by our system, in this case /dev/sd'''e.'''</div>
 
<div style="text-align: left;">We can see the name of our device in the system: '''/dev/sdX''' where X is the character assigned by our system, in this case /dev/sd'''e.'''</div>
 
 
 
<div style="text-align: left;">Now we have to ensure that the MicroSD Card is completely clean. We can use the following command to do that:</div>
 
<div style="text-align: left;">Now we have to ensure that the MicroSD Card is completely clean. We can use the following command to do that:</div>
 
  sudo dd if=/dev/zero of=/dev/sdX bs=1024 count=1024<div style="text-align: left;">Where '''X''' is the character returned previously by your system, for example, in the previous situation:</div>
 
  sudo dd if=/dev/zero of=/dev/sdX bs=1024 count=1024<div style="text-align: left;">Where '''X''' is the character returned previously by your system, for example, in the previous situation:</div>

Revision as of 18:35, 10 May 2018

Introduction

This page explain how to create a microSD card to boot IGEP boards with  software distributions ( yocto, Ubuntu, Debian ...).

  • Now we can see an image of which are the steps to boot any module.

With a general processor all start with MLO file and U-Boot.img. Also it is the same procedure for Freescale- NXP. If you want to see how to create these files follow this link.

Next step is that once the processor is initialized,call the linux kernel making the execution of  your operative system available.

Finally your OS runs and you can initialize the board correctly 


How to SD.PNG


General Processors

Inside General processors we can find Texas Instruments

  • The microsd card must be content at latest 2 partitions.
  • The first one must be primary partition with the boot flag mark and formated using FAT(16 or 32) file system.
  • All names used in this partition must be msdos names (applies to OLD OMAP35xx processor).
  • The processor must load a first program called MLO, this program must reside in the first partition, this program it's also called x-loader or uboot-spl.

The processor when boot ONLY load and execute the MLO program and ignore all the rest it's the X-loader(MLO) the program responsible to load the next programs such kernel or uboot if you use this last one approach.


Information.jpg Freescale has a different structure


Freescale-NXP Processors

  • The microsd card must be content at latest 1 partitions.
  • The primary partition can be formatted with any filesystem that u-boot can mount.
  • The Processor will load the u-boot.imx it include the SPL and u-boot.

After load this u-boot.imx, u-boot will be ready for boot the kernel.

Therefore, we are going to setup a microSD card with these requirements and install a custom software distribution into it.


Prerequisites

  • PC with Linux (We use for this how to Ubuntu 16.04 LTS)
  • MicroSD Card (4 Gbytes - class 4) or bigger ...
  • Tools such, fdisk, mkfs.ext3, mkfs.vfat, gparted ...
  • Cross Toolchain included in Ubuntu 16.04 LTS gcc version 4.9.3 (Ubuntu/Linaro 4.9.3-13ubuntu2).


ToolChain


In order to start developing with an IGEP PROCESSOR BOARD we can use a microSD Card to flash our system and boot from it. Most of the cases is the easiest way to boot a board.

The following steps details how to prepare a booteable MicroSD Card

Prepare a SD to boot

Information.jpg The following steps has been tested using an Ubuntu 16.04
First of all it is important to detect which device is our microSD Card. In order to do that we can follow this instructions in a Linux terminal:
1- Clean the dmesg information:
sudo dmesg -c
2- Insert the microSD Card and show the dmesg information:
dmesg
The result have to be similar to this:

SD1 .png

We can see the name of our device in the system: /dev/sdX where X is the character assigned by our system, in this case /dev/sde.
Now we have to ensure that the MicroSD Card is completely clean. We can use the following command to do that:
sudo dd if=/dev/zero of=/dev/sdX bs=1024 count=1024
Where X is the character returned previously by your system, for example, in the previous situation:
sudo dd if=/dev/zero of=/dev/sde bs=1024 count=1024
Now we are ready to create the corresponding partitions in our MicroSD Card.

How to partition the MicroSD card

There are several ways to partition a MicroSD Card. In this post we are using the GParted tool that can be installed as:
sudo apt-get install gparted

Other tools as sfdisk and mkfs are useful too.

It is important to difference between a MicroSD Card for a NXP processor and the other cases. The process of partition is similar but, in the case of NXP chips, there exists some differences. 

General case process:

SD2.png

SD3.png

SD4.png

Preparing the microSD card

Open a terminal window and clear your dmesg using:

sudo dmesg -c

Now insert a new microsd card in your PC and then check your dmesg:

dmesg

You should see something like this:

mmc0: new high speed SDHC card at address 0001
mmcblk0: mmc0:0001 00000 3.79 GiB
mmcblk0: unknown partition table

Ensure all in your microsd card it's erased:

$ sudo dd if=/dev/zero of=/dev/mmcblk0 bs=1024 count=1024
[sudo] password for jdoe:




sudo sfdisk /dev/sdc <<EOF
label: dos
16065,128520,0x0C,*
144585,,,-
EOF

NORMAL
sudo sfdisk /dev/sdc <<EOF
label: dos
63,144522,0x0C,*
160650,,,-
EOF

sudo mkfs.vfat -F32 /dev/sdc1 -n boot
sudo mkfs.ext3 /dev/sdc2 -L rootfs

sudo dd if=./u-boot.imx of=/dev/sdc bs=512 seek=2; sync

Downloading GParted

In order to prepare a micro SD with your already generated u-boot you need to flash the u-boot.imx using the command dd. (?)

It is important to prepare your micro SD card first creating a partition that leave some free space for the u-boot.imx. It can be used GPARTED as it is shown in the image.


GPARTED.png


In this image we can see the devices plugged in our computer. And it can be installed with this command.

sudo apt-get install gparted

When the install procedure ends you can call the program from your system tools menu or directly using a terminal console.

 

Make the partition of the SD

Now we are going to see some steps with the two methods.

First creating the partition and then how procedure with each processor.

Defining Partitions

GPARTED
The next step it's create the msdos table partition for it you should click in the "Device" menu and then in the "Create Partition Table" option.
2 FOTOS

Check the default option it's create a msdos partition table.

After that you can Apply.

SFDISK
sudo sfdisk /dev/ <<EOF
label: dos
16065,128520,0x0C,*
144585,,,-
EOF


After that we will create this boot partition first for the IGEP General processors

Create the BOOT Partition - General IGEP Processor based

GPARTED
This Step it's only for OMAP35xx, DM37xx, AM335x, OMAP5432 processor based IGEP boards.

The Next step it's create the partitions for it you should go to the partition menu and select the "New" option then the application show a window like this:

We will configure the partition as:

  • Primary Partition
  • Format: FAT32
  • Size: 100 MegaBytes
  • Free Space Preceding: 0 MiB
  • Label: Boot
  • Align to: cylinder

It is recommended to apply changes now or you might get an error later.

SFDISK
Bla bla bla


Specifically for the IGEP NXP-Freescale

Create the BOOT Partition - IGEP NXP-Freescale Processor based

GPARTED
This Step it's only for iMX6 processor based IGEP boards.

The Next step it's create the partitions for it you should go to the partition menu and select the "New" option then the application show a window like this:

We will configure the partition as:

  • Primary Partition
  • Format: FAT32
  • Free Space Preceding: 8 MiB
  • Size: 100 MegaBytes
  • Label: Boot
  • Align to: cylinder

It is recommended to apply changes now or you might get an error later.

SFDISK
$ sudo mkfs.vfat -F 32 /dev/ -n boot
$ sudo mkfs.ext3 /dev/ -L rootfs


After these steps we will make the root filesystem partition

Create the ROOTFS Partition

GPARTED
The Next step it's create the root file system partition.  First you should select the unallocated partition area and then  you should go to the partition menu and select the "New" option then the application show a window like this:

We will configure the rootfs partition as:

  • Primary Partition
  • Format: EXT4
  • Size: All the Rest
  • Label: Rootfs

At end we will click on "Add" button.

or

After all apply all changes

SFDISK

Then you only have to use dd command in order to copy the u-boot.imx to the SD card.

Please, be sure you have write correctly the following command because in if not, it can corrupt your computer.

u-boot.imx copy
$ sudo dd if=//u-boot.imx of=/dev/ bs=512 seek=2
$ sync

For example

u-boot.imx copy
$ sudo dd if=/home/user/Project/u-boot/u-boot.imx of=/dev/sdd bs=512 seek=2
$ sync


Finally we will make this.


Select "Boot flag" for the boot partition

 

GPARTED

Now we must select the boot flag for the first partition for it we use the right mouse button over the boot partition and select "Manage Flags" option

Now we have the microsd prepared for copy the boot files



How to boot each part

Now we will see where to put each part and how to.

U-Boot

General processors

After build or download the MLO and u-boot you should follow the next steps:

  • Copy MLO and u-boot.img to primary boot partition
$ cp MLO u-boot.img /media/user/boot

You can follow this link if you want build the MLO and u-boot


Freescale processors

  • Copy u-boot.imx using dd before primary partition in raw mode as
sudo dd if=/home/user/u-boot-imx/u-boot.imx of=/dev/sde bs=512 seek=2

Where /dev/sde is your microsd card


You can follow this link you want build the u-boot.imx


Root file System

In this tutorial we will use the linaro headless (soft floating) image as rootfs but you can use your favorite rootfs also.


 
  Here there are many articles about how to get many other [index.php/Category:Software_distributions software distributions].


Here you've the linaro nano 11.09 (soft floating) available for download from the ISEE server.

Notes: You must build your programs with the hard floating if your rootfs is build with it.

Notes: IGEPv5 must use Hard floating Rootfs


Create the Rootfs mount point

Go to /media directory and create one sub-folder called "binary"

cd /media

sudo mkdir binary

Mount the RootFS partition

Mount the rootfs partition using the 'binary' directory

$ media > sudo mount /dev/mmcblkp2 /media/binary

Untar the rootfs package

Copy "linaro-m-headless-tar-20101108-2.tar.gz" file inside the /media directory and untar the file

$ media > sudo tar xvfz linaro-m-headless-tar-20101108-2.tar.gz


Now you should see inside your rootfs partition a similar structure like this.

Install the kernel modules

Now you should install your kernel modules inside your root file system.

$ media > cd /home/jdoe/linux-omap-2.6

$ /home/jdoe/linux-omap-2.6> sudo make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- modules_install INSTALL_MOD_PATH=/media/binary

Alternatively if you downloaded the binary package uncompress it inside the directory /media/binary

Install the kernel Image

Just copy the zImage inside your boot partition, remember before that you must mount your mmc boot partition.

$ /home/jdoe/linux-omap-2.6> sudo cp arch/arm/boot/zImage /media/boot/
if you're using dtb kernel as 3.8.y you must copy the dtb too.
$ /home/jdoe/linuz-omap-2.6> sudo cp arch/arm/boot/dtbs/omap5-igep0050.dtb /media/boot

After that you can unmount the boot & rootfs partitions.

Now we're ready for test our new microsd card

Kernel & Modules

You can follow this other howto about [index.php/The_Linux_kernel how compile and install the Linux Kernel].


Test your new MicroSD

You can test your new microSD card with a Serial client such as PuTTy. [index.php/Using_serial_debug_port_to_communicate Here] is an explanation about how to configure it.

(Note that speed should be configured to 115200 bauds).

If you already have configured it or you are using another Serial client and you have connected the Serial cable to the IGEPv2 board, then you are ready to test your microSD.

Insert the microSD in your IGEPv2 board and power up the board.