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Altera_Forum's avatar
Altera_Forum
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21 years ago

uClinux .data segment in SDRAM?

For a number of reasons, I'd like to run my kernel in SRAM but allocate data memory (i.e. socket buffers) in SDRAM. This seems possible with a NIOS 'Hello World' application, or the like...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
20 years ago

I occured to me that your problem might be caused by the address you gaven to SDRAM. It is not a good idea to give address 0 to anyone. It will be intepreted as NULL. When you want to allocated a DAM buffer through kmalloc, the slab allocator will try to grab pages, and the first page (with address 0) will be returned, making the slab think there is no memory available...

<div class='quotetop'>QUOTE </div>

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0x0-0x07ffffff -- 128MB of SDRAM

0x08000000-0x09000000 -- 16 MB of SRAM[/b]

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