lowRISC / lowrisc-chip

The root repo for lowRISC project and FPGA demos.
http://www.lowrisc.org/
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Set MAM addresses and sizes from chip_top #12

Open wallento opened 8 years ago

wallento commented 8 years ago

The MAM provides the information about the memory regions it can access. This should be configured in chip_top based on the definitions of dev_map.vh and consts.vh.

wsong83 commented 8 years ago

BRAM_BASE/BRAM_OFFSET and MEM_BASE/MEM_OFFSET already provide this information? The only notice here is BRAM_BASE is not defined when BRAM is not there.

wallento commented 8 years ago

We also need the size, that is currently missing.

Created this issue because I don't want to change this last minute before the release now.

wsong83 commented 8 years ago

Yes, change after release.

For the size, the size of the memory section or the size of the data bus? For each memory section, OFFSET + 1 is the size in byte.

wsong83 commented 8 years ago

It seems I will need to differentiate mask and size due to the support for tagged memory. With tagged memory, the main memory is reduced to an unaligned size like 224MB for a 256MB memory, where the higher 32MB reserved for tag.

As a result, the routing configuration for nasti_crossbar in socip will be changed accordingly.