2009-03-10 10:40:43     non cahing the particular portion of the sdram

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2009-03-10 10:40:43     non cahing the particular portion of the sdram

hari a (INDIA)

Message: 70703   

 

Dear All,

 

We have created the ldr file from vdsp with some of the sdram portion is non-cached. Because the same section is using for MDMA .

 

This one we are using as a loadable module in uClinux.

 

Here(uClinux)  how we have to non-cache the particular sdram portion which was used in loadable module?

 

 

 

 

 

 

 

Thanks,

 

Hari

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2009-03-10 10:54:29     non cahing the particular portion of the sdram

Michael Hennerich (GERMANY)

Message: 70705    You need to allocate none cacheable DMA memory using following functions.

 

void *dma_alloc_coherent(struct device *dev, size_t size,

dma_addr_t *dma_handle, gfp_t gfp);

 

void dma_free_coherent(struct device *dev, size_t size, void *vaddr,

dma_addr_t dma_handle);

 

There are various examples in Blackfin DMA capable device drivers.

 

-Michael

 

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2009-03-10 12:51:49     Re: non cahing the particular portion of the sdram

Robin Getz (UNITED STATES)

Message: 70709   

 

Hari:

 

> We have created the ldr file from vdsp

 

As soon as I see that - I stop reading. Do not do that - it is not supported. Not supported means that no one will answer any questions you have.

 

The only thing that compiles things that works for compiling the Linux kernel  - is gcc - see inux-2.6.x/Documentation/Changes - Current Minimal Requirements : Gnu C

 

-Robin

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2009-03-10 15:14:39     Re: non cahing the particular portion of the sdram

Mike Frysinger (UNITED STATES)

Message: 70717   

 

LDR files and Linux do not mix ... nor does it really make sense

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