linux kernel compilation for arm AM335x .

abhinandan attri

Prodigy 170 points

sir

I am compiling the kernel with loadable module kept in directory "Driver/char/HelloWorld.c".

I make entry in Kconfig and MAKEFILE in same Directory for HelloWorld.c.

then i have ecuted following commands.

export ARCH=arm

export CROSS_COMPILE=arm-linux-gnueabihf-

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- pcm051_defconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig        /selected the HelloWorld as loadable module*/

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- uImage

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules

uImage from arch/arm/boot  copied to boot partition of  micro sd card.

sudo make ARCH=arm INSTALL_MOD_PATH=/media/username/rootfs modules_install

everthing is fine no error appear during above procedure.i have check that Driver/char/HelloWorld.c get compiled and Driver/char/HelloWorld.o is created.

after this procedure i have put the micro SD card in the board  and power ON  the board.i have expored  the HelloWorld.o ,i am searching for this HelloWorld.o but not found in rootfs.

Can you tell me is there any mistake in the procedure or i am not looking in the right place.?

over 9 years ago

0 Kemal R. Shakir over 9 years ago

TI__Guru 55345 points

Hello abhinandan,

The kernel modules has .ko extension. Please check if /lib/modules/<kernel version>/kernel/drivers/char/helloworld.ko exist.

Best regards,
Kemal

0 abhinandan attri over 9 years ago in reply to Kemal R. Shakir

Prodigy 170 points

Sir i have checked there could not found. Can you check procedure, is there any mistake.

0 abhinandan attri over 9 years ago in reply to Kemal R. Shakir

Prodigy 170 points

When i have checked micro sdcard with card reader. This module is at your specified path but When i am using This card with my board, i am unable to found the module at same address. I have putup the module in char/misc/helloworld. C. But this folder is not appearing in same path..

0 Kemal R. Shakir over 9 years ago in reply to abhinandan attri

TI__Guru 55345 points

Seems somewhere in your Makefile the goal is set 'y' for build in object
(obj-y) instead of 'm' (obj-m) for loadable module.

0 Titusrathinaraj Stalin over 9 years ago in reply to abhinandan attri

TI__Guru** 116100 points

Dear abhinandan,
In addition to Kemal suggestions, I give you some insights on this issue.

When i have checked micro sdcard with card reader. This module is at your specified path but When i am using This card with my board, i am unable to found the module at same address. I have putup the module in char/misc/helloworld. C. But this folder is not appearing in same path..

When you want to add some driver into linux kernel, you have to follow the below steps.

1) You have to put the *.c file in appropriate folder of linux structure (char/misc/helloworld.c)
2) Then you have to modify the Makefile and Kconfig of that folder (ex: char/misc/Makefile & char/misc/Kconfig)
Need to mention file name with macro in Makefile
Ex:
obj-$(CONFIG_HELLO_DRIVER) += helloworld.o

Need to mention about the driver details and dependencies of driver etc., in Kconfig

Ex:
config HELLO_DRIVER
tristate “Sample linux hello world driver”
default n
help
If you say “Y” here, you will enable the sample driver support in kernel
3) Now you can see the "Sample linux hello world driver" option in menuconfig.
4) Now you can choose the driver as module (M) then build it.

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules

Still, if you are facing the problem, please post the log and share all those files, we will look into it.

0 abhinandan attri over 9 years ago in reply to Kemal R. Shakir

Prodigy 170 points

it is "obj-$(CONFIG_HELLO_MODULE) +=helloworld.o"

0 Titusrathinaraj Stalin over 9 years ago in reply to abhinandan attri

TI__Guru** 116100 points

It looks good.
What is the output log getting when you do this command " make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules" ?
Can you post that log ?

0 Kemal R. Shakir over 9 years ago in reply to Titusrathinaraj Stalin

TI__Guru 55345 points

I would like to see the output of this command, executed from the top linux kernel directory.

cat .config | grep CONFIG_HELLO_MODULE

Could you post this feedback, too?

0 abhinandan attri over 9 years ago in reply to Titusrathinaraj Stalin

Prodigy 170 points

sir,

in above procedure there no need to run following command before step-4:-

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- uImage

asking only for information

0 Titusrathinaraj Stalin over 9 years ago in reply to abhinandan attri

TI__Guru** 116100 points

Dear Abhinandan,
Yes, ofcourse you have to run "make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- uImage " then build modules.
I presume that you have ran the command already and need to build this helloworld driver as module.

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- uImage
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules

If you are not able to make it successful then please provide the log of below commands (including Kemal requested log)

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules
cat .config | grep CONFIG_HELLO_MODULE

FYI:
You can also get the config settings after boot the linux.
zcat /proc/config.gz | grep HELLO_MODULE

0 abhinandan attri over 9 years ago in reply to Titusrathinaraj Stalin

Prodigy 170 points

sir,

in above procedure there no need to run following command before step-4:-

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- uImage

asking only for information

0 abhinandan attri over 9 years ago in reply to Titusrathinaraj Stalin

Prodigy 170 points

I am excuting the following:-

Make ARCH=arm INSTALL_MOD_PATH=/media/abhinandan/rootfs/ modules_install

And is giving warning :-you need to install modules-init-tools

Sir I want say u again. It copy the hello_world. Ko to card but when I boot from the card It does not show hello_world at same path.

I have dought the we are missing something still.

0 abhinandan attri over 9 years ago in reply to abhinandan attri

Prodigy 170 points

Sir,
i am not doing anything with "Device Tree Blob" .i need compile to "Device Tree Blob " also?
with regards

0 Titusrathinaraj Stalin over 9 years ago in reply to abhinandan attri

TI__Guru** 116100 points

Sir I want say u again. It copy the hello_world. Ko to card but when I boot from the card It does not show hello_world at same path.
I have dought the we are missing something still.

Then please copy the that .ko file through pendrive and paste into your filesystem.
After that you can insert the driver manually via "insmod" command.

insmod helloworld.ko

i am not doing anything with "Device Tree Blob" .i need compile to "Device Tree Blob " also?

You no need to do anything with DTB unless you use DTS concept in your driver.

0 abhinandan attri over 9 years ago in reply to Titusrathinaraj Stalin

Prodigy 170 points

I have manually putup the file but still status is same.

0 Titusrathinaraj Stalin over 9 years ago in reply to abhinandan attri

TI__Guru** 116100 points

Sorry I'm helpless until you provide we requested information (build logs, log when you insert manually the *.ko via insmod)

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linux kernel compilation for arm AM335x .