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Altera_Forum's avatar
Altera_Forum
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10 years ago

mSGDMA, Qsys, and Linux Integration

So I've been trying to get the Modular SG-DMA working in a Qsys project tied with Linux. I can get it to show up in the device tree, be recognized by Linux in /sys, and it looks like the memory mappi...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

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What value is MAP_PIO_SIZE?

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Also, in reply to this one-- I updated all my memory mappings and sizes recently. I wouldn't call it MAP_PIO_SIZE, but instead LW_REGS_SIZE, which is 2 MB. Check out page 1-19 and 7-6 of the HPS Technical Reference Manual. The LW FPGA devices run from 0xFF200000 to 0xFF400000, or 0x200000. This gets mapped to virtual memory in Linux, and there is also the fast bridge which runs from 0xC0000000 and is 960 MB, or to 0xFC000000 (0x3C000000 size).

The graphic on 7-6 saved me a lot of time.