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Altera_Forum's avatar
Altera_Forum
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16 years ago

Linux with MMU on NEEK

Hi, all. I'm testing Linux MMU version, on my NEEK. http://www.nioswiki.com/linux It works fine and I can use "bash" shell. This is the evident proof that we are using the true 'fo...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Oh, sorry. It's racing.

The descriptors must be flushed before we re-start the DMA. 


//    writel((unsigned long)desc1, base + ALTERA_SGDMA_NEXT_DESC_POINTER);
    writel(((unsigned long)virt_to_phys(desc1)), base + ALTERA_SGDMA_NEXT_DESC_POINTER);
    flush_cache_all();  // <- Must be here.
    writel(ALTERA_SGDMA_CONTROL_RUN_MSK | ALTERA_SGDMA_CONTROL_PARK_MSK,
           base + ALTERA_SGDMA_CONTROL);    /* start */
    // flush_cache_all();   // <- To flush descriptors from the cache.  Indeed, it's enough to flush the D-cache.
    return 0;
}
Kazu