| Summary: | custom run of ulx3s with 85k LUTs 5G part, and 128 mbyte (1 gigabit) SDRAM | ||
|---|---|---|---|
| Product: | Libre-SOC's first SoC | Reporter: | Luke Kenneth Casson Leighton <lkcl> |
| Component: | Source Code | Assignee: | Luke Kenneth Casson Leighton <lkcl> |
| Status: | CONFIRMED --- | ||
| Severity: | enhancement | CC: | libre-soc-bugs, programmerjake, staf |
| Priority: | --- | ||
| Version: | unspecified | ||
| Hardware: | PC | ||
| OS: | Linux | ||
| See Also: | https://bugs.libre-soc.org/show_bug.cgi?id=1146 | ||
| NLnet milestone: | --- | total budget (EUR) for completion of task and all subtasks: | 0 |
| budget (EUR) for this task, excluding subtasks' budget: | 0 | parent task for budget allocation: | |
| child tasks for budget allocation: | The table of payments (in EUR) for this task; TOML format: | ||
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Description
Luke Kenneth Casson Leighton
2021-04-27 00:03:26 BST
If we can find a good supply, it may be worth getting faster ram: I found the MT46V64M16 series after a little searching -- idk if Micron still makes it though... https://www.digikey.com/en/products/base-product/micron-technology-inc/557/MT46V64M16/37720 digikey lists it as obsolete unfortunately. alliance may have faster (edit: no) https://www.digikey.co.uk/products/en?t=774&pv570=400796&pv142=120140&pv1291=263924 all the same part. no other digikey. trying mouser. nope. only Alliance available for the TSOP-66 in mouser, and they only have the 32x16 part (64 mbyte). one other potential option (that may be waay too much work for a few k$): replace chip with a ddr2/3 ram chip and reroute that small section of the pcb to accommodate a bga. iirc the ecp5 has a hw ddr3 interface and the gpio is fast enough to run ddr2. Also, the total amount has gone down to around $4100 due to bitcoin's value going down (In reply to Jacob Lifshay from comment #3) > one other potential option (that may be waay too much work for a few k$): exactly. also, as you're aware: we're on a serious time-crunch. we cannot add yet more dependencies to the critical path. i know how much PCB development costs in both time and money. the fact that the ulx3s PCB is done, designed, tested and proven is extremely important. (In reply to Jacob Lifshay from comment #4) > Also, the total amount has gone down to around $4100 due to bitcoin's value > going down *sigh* ok With current chip crunch and part lead times I'm not sure thinking about own custom PCB is a good idea; especially if it is time critical. There is a 85F version of ULX3S available on crowdsupply: https://www.crowdsupply.com/radiona/ulx3s If speed is really important maybe better to think about Intel/Xilinx FPGA anyway. For example Trenz Electronics has a whole bunch of them: https://shop.trenz-electronic.de/en/Products/Trenz-Electronic/ They also do custom modification to boards or your own design (like the MEGA65 prototype). (In reply to Staf Verhaegen from comment #7) > With current chip crunch and part lead times I'm not sure thinking about own > custom PCB is a good idea; especially if it is time critical. fortunately there is stock - not very much, but at least some. (for now) > There is a 85F version of ULX3S available on crowdsupply: > https://www.crowdsupply.com/radiona/ulx3s it only has 32 mbytes of RAM. this is nowhere near enough. > If speed is really important maybe better to think about Intel/Xilinx FPGA > anyway. For example Trenz Electronics has a whole bunch of them: > https://shop.trenz-electronic.de/en/Products/Trenz-Electronic/ https://shop.trenz-electronic.de/en/Products/Trenz-Electronic/TE0741-Kintex-7/ interesting. modular design. > They also do custom modification to boards or your own design (like the > MEGA65 prototype). these are non-libre tools, unfortunately. our customer has a specific need for Libre tools. that means ECP5 at the moment, until nextprn can support other FPGAs. we've an additional requirement for BMC support: PCI-e and Ethernet. Ethernet can be covered with this: https://www.waveshare.com/product/DP83848-Ethernet-Board.htm also here is a kicad board with PCIe 1x edge connections. should be easy to either adapt or make a breakout https://github.com/ghent360/PrntrBoardV2 https://github.com/KiCad/kicad-symbols/blob/master/Connector.lib BUS_PCIexpress_x1 (In reply to Luke Kenneth Casson Leighton from comment #10) > https://github.com/KiCad/kicad-symbols/blob/master/Connector.lib That's their old repo. > > BUS_PCIexpress_x1 Here's all the pcie edge connectors: https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCI_Express_Mini.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCI_Express_Mini_Dual.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCI_Express_Mini_Full.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCI_Express_Mini_Half.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCIexpress_x1.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCIexpress_x16.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCIexpress_x4.kicad_mod https://gitlab.com/kicad/libraries/kicad-footprints/-/blob/8fa36dfa3423d8777472e3475c1c2b0b2069624f/Connector_PCBEdge.pretty/BUS_PCIexpress_x8.kicad_mod https://www.digikey.com/en/products/detail/lattice-semiconductor-corporation/ISPPAC-CLK5406D-01SN48I/2751347 nuts. Lattice VERSA ECP5 has a block buffer/generator IC which creates the PCIe master clock. it'll be nowhere near as simple as "just wire out PCIe from the FPGA". after a little searching: whitequark has a pcie phy: https://github.com/whitequark/Yumewatari/blob/master/yumewatari/gateware/phy.py Also, found a board with an ecp5 and pcie: https://github.com/gatecat/TrellisBoard |