2009-05-04 03:31:24 linker placement

zigma dsp (GERMANY)

Message: 73543

Hi all,

In the example of simple application with ASM, it shows some .rodata section. Which file should I refer to, to understand what each sections means for a. Compiler and b. assembler. Is this what the linker script is for, and so where do I find the same? Are there any documentation, that explains what each section mean?

If I am correct, the building method used in bFLAT. It support 2 types: FDPIC ELF and FLAT. Is FLAT same as FRB (fully relocatable binaries)? Where can I find a picturesque description of the 2 formats (like a diagram..something showing the sections and how data is moved)?

Thanks &

Regards

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2009-05-04 09:58:08 Re: linker placement

Robin Getz (UNITED STATES)

Message: 73565

Zigma:

Before diving down into the details - (which are all in various places of the wiki) what are you trying to do?

If you are developing drivers for the Linux kernel - they are not relocatable. (fixed at link time), if you are developing bare metal - they are not relocatable. (fixed at link time),If you are developing linux modules, or linux applications or linux libraries - they are always relocatable.

-Robin

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2009-05-05 11:34:11 Re: linker placement

zigma dsp (GERMANY)

Message: 73672

Thank you Robin for your time.

I am trying to understand the memory placement. This includes the 'sections' to where to map to and how the build formats work.

I guess I could split the question to 2:

1. Where do I find info of what all 'sections' are available for the user, to place code and data (compiler and assembler)

and to what memory segment each are mapped to?

2. In the docs, I saw about FDPIC and FLAT. I have read the docs, and I wasn't able to visualize what is happening when I choose a particular format. For instance, how does the PIC works with the GOT or FLAT works with Relocation Tables. I do not know how much I need to know them.

Regards

JA.

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2009-05-05 14:29:20 Re: linker placement

Robin Getz (UNITED STATES)

Message: 73684

Zigma:

You never answered my question - what are you trying to build - Linux applications or bare metal applications?

-Robin

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2009-05-06 00:56:37 Re: linker placement

zigma dsp (GERMANY)