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Altera_Forum
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9 years ago

(CycloneV) Writing 128bits to FPGA at once using linux kernel module

Hi, I'm trying to write a kernel module that writes 128bits of data to the FPGA using the HPS-to-FPGA bridge. The bridge width is configured as 128 Bits in Qsys and I'm using memcpy_toio() to w...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

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A colleague of mine was able write 64bits at once using the HWLib and the Socal.h library from userspace, but I those seem to be designed for userspace only. I'll try to manipulate the fn_mod registers, though from the documentation I gathered that the merging should be enabled by default.

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Here's a question-- is memcpy_toio limited to 32-bits due to it's interaction with the AXI bus? Why not try abstracting as a long int and doing a direct memory write to test?

EDIT: fixed type