Hi Jeshwanth, On Mon, Feb 10, 2014 at 11:00 PM, Jeshwanth Kumar N K < jeshkumar555@gmail.com> wrote:

Hi Arun,

Thanks for the reply :)

Which means all the firmware available in /lib/firmware loads to device when device attached? (I mean to volatile memory of device)

I have one more doubt/assumption in this.

What I feel is, dynamically loading firmware is because of loading the firmware for specific platform. i.e. Windows and Linux firmware (for same device) are different, Windows loads firmware which is created for Windows, and Linux loads firmware created for Linux systems.

I don't think so. These binaries will not depend on OS(windows or linux) and will be specific to your pl310 controller. PL310 is a microcontroller and the loaded firmware is a program which runs on that. It will be hardware specific. Just like you need to create different binary for 8051, PIC or ARM. HTH. Thanks, Arun

Please let me know whether my assumption is right :)

On Mon, Feb 10, 2014 at 7:27 PM, Arun KS <getarunks@gmail.com> wrote:

...

Hi Jeshwanth,

On Mon, Feb 10, 2014 at 6:59 PM, Jeshwanth <jeshkumar555@gmail.com>wrote:

...

Hello List,

I came to know that, linux loads firmware for my dma everytime it boots. But I don't understand, why it is required to load everytime it boots, don't dma holds which is loaded previously.

Might be because it is loaded in to some volatile memory like DDR, which does not persist during reboots.

Thanks, Arun

...

AFAIK, firmware is a program which runs in devices.

Please correct me if I am wrong.

...

Thanks :)

Regards, Jeshwanth

Sent from my HTC

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-- Regards Jeshwanth Kumar N K Bangalore, India

Thanks Peter and Arun, I can understand now :) Any good documentation to understand UEFI ? On Fri, Feb 14, 2014 at 10:32 AM, Peter Teoh <htmldeveloper@gmail.com>wrote:

FYI, the "firmware" are loaded from flash:

http://en.wikipedia.org/wiki/Flash_memory

which means microcontroller (or microprocessor) + DMA/DDR memory + flash are the usual makeup of an embedded system. flash are non-volatile, but normally it is slower and cannot be executed as CPU or microncontroller instruction. which is why you will need to load it into memory to be executed:

http://lwn.net/Articles/135472/

cheers.

On Mon, Feb 10, 2014 at 9:29 PM, Jeshwanth <jeshkumar555@gmail.com> wrote:

...

Hello List,

I came to know that, linux loads firmware for my dma everytime it boots. But I don't understand, why it is required to load everytime it boots, don't dma holds which is loaded previously. AFAIK, firmware is a program which runs in devices.

Please correct me if I am wrong.

Thanks :)

Regards, Jeshwanth

Sent from my HTC

_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

-- Regards, Peter Teoh

-- Regards Jeshwanth Kumar N K Bangalore, India