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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
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20 years ago

Hi Wentao,

I went back and started from scratch on this, and I got the kernel to use SDRAM as GFP_DMA. I can allocate a buffer using 'kmalloc' in SDRAM. However, I have since encountered a couple new problems:

1) I can't seem to kmalloc more than 4MB -- not sure if this is normal behavior or not.

2) I get Perror: Bad Address when I try to send an SDRAM buffer over a TCP socket, regardless of the size of the buffer. Googling for this perror I see that it's caused by an 'invalid address'.

Thanks again, I think I'm getting close,

Ryan