| *** tpb <[email protected]> has joined #yosys | 00:00 | |
| *** nelgau_ <[email protected]> has joined #yosys | 00:23 | |
| *** nelgau <[email protected]> has quit IRC (Read error: Connection reset by peer) | 00:23 | |
| *** crzwdjk <[email protected]> has quit IRC (Ping timeout: 260 seconds) | 00:32 | |
| *** crzwdjk <[email protected]> has joined #yosys | 00:34 | |
| *** nelgau <[email protected]> has joined #yosys | 00:42 | |
| *** nelgau_ <[email protected]> has quit IRC (Ping timeout: 255 seconds) | 00:43 | |
| *** lexano <[email protected]> has quit IRC (Ping timeout: 256 seconds) | 01:13 | |
| *** citypw <citypw!~citypw@gateway/tor-sasl/citypw> has joined #yosys | 01:58 | |
| *** nelgau <[email protected]> has quit IRC (Read error: Connection reset by peer) | 02:13 | |
| *** nelgau_ <[email protected]> has joined #yosys | 02:13 | |
| *** bjork1intosh <bjork1intosh!~bjork@2600:1700:5400:c80:486c:ed5a:b943:b237> has quit IRC (Ping timeout: 256 seconds) | 02:32 | |
| *** bjorkintosh <bjorkintosh!~bjork@2600:1700:5400:c80:2fc9:1390:d733:95d5> has joined #yosys | 02:33 | |
| *** cr1901_ <cr1901_!~cr1901@2601:8d:8600:226:5021:bd23:1d17:ff62> has joined #yosys | 03:14 | |
| *** cr1901 <cr1901!~cr1901@2601:8d:8600:226:8f0:f7c2:6474:40e6> has quit IRC (Ping timeout: 268 seconds) | 03:18 | |
| *** jn <jn!~quassel@user/jn/x-3390946> has quit IRC (Ping timeout: 256 seconds) | 05:00 | |
| *** jn_ <jn_!~quassel@2001-4dd3-d68e-0-20d-b9ff-fe49-15fc.ipv6dyn.netcologne.de> has joined #yosys | 05:00 | |
| *** nelgau_ <[email protected]> has quit IRC (Read error: Connection reset by peer) | 06:00 | |
| *** uis246[m]1 <uis246[m]1!uis246matr@2a01:4f8:c012:5b7:0:1:0:129> has quit IRC (Quit: Idle timeout reached: 172800s) | 06:01 | |
| *** nelgau <[email protected]> has joined #yosys | 06:01 | |
| *** FabM <FabM!~FabM@2a03:d604:103:600:2e60:8c7c:e8fb:7990> has joined #yosys | 06:32 | |
| Myrl-saki | Hi. :) I finally got an ECP5 board, how do I use registered output BRAM? | 06:43 |
|---|---|---|
| Myrl-saki | Oh wait. | 06:45 |
| Myrl-saki | In hindsight, maybe it's getting inferred? And that's why I'm having weird timings. | 06:45 |
| Myrl-saki | TL;DR is that the slowest path right now is the BRAM, so I wanted to use registered output. So I did. But it still considers the output to not be regisetred. | 06:46 |
| Myrl-saki | At least if I'm understanding it correctly.. | 06:46 |
| Myrl-saki | https://gist.github.com/adrianparvino/ce9d10bd0be389e9bffdd0626fe83990 | 06:47 |
| tnt | you can check in the .json to see if that ram is configured with output register. | 06:48 |
| Myrl-saki | Huh true | 06:49 |
| Myrl-saki | Ah | 06:49 |
| Myrl-saki | test | 06:49 |
| Myrl-saki | "REGMODE_A": "NOREG", | 06:49 |
| Myrl-saki | Seems like that's a no. | 06:50 |
| tnt | I'm not even sure if ecp5 infer ram supports output reg TBH. | 06:50 |
| Myrl-saki | Okay, so that's answered, at least. | 06:51 |
| Myrl-saki | Hm. | 06:51 |
| Myrl-saki | Yeah, maybe I'm misunderstanding somethign here? | 06:51 |
| Myrl-saki | ``` | 06:51 |
| Myrl-saki | Info: 5.6 5.6 Source ram.cells_a.0.1.DOA7 | 06:51 |
| Myrl-saki | Is this the input or an output of the RAM? | 06:52 |
| Myrl-saki | Whoops, I better send my RAM implementation too. | 06:52 |
| tnt | output. | 06:52 |
| tnt | It's the time from the clock edge to the moment the data shows up on the data out pins. | 06:52 |
| Myrl-saki | https://gist.github.com/adrianparvino/238392f626a15f70e44286527f51a75b | 06:52 |
| tnt | The ECP5 BRAM have a very long clock-to-out on BRAMs. | 06:53 |
| tnt | well this ram model doesn't have an output register ... | 06:53 |
| Myrl-saki | Wait, give me a bit to think about this lol. So, my original implementation was to just do `assign out[...] = cells[addr];` | 06:54 |
| tnt | enabling out_reg on ecp5 means you have the input registers (because they are bram, always synchronous), then another register on the data output. So you have a read latency of 2 cycles. | 06:54 |
| tnt | Your implementation was an asynchronous read ram ... that doesn't even _map_ to BRAMs at all ... | 06:55 |
| Myrl-saki | Okay, I think I get it. So the way this works is that it actually latches the address? | 06:56 |
| Myrl-saki | Like, one way I can see this is: `assign out[...] = cells[a_reg]; ... a_reg <= addr;`? | 06:57 |
| tnt | yes | 07:05 |
| *** mobius <[email protected]> has quit IRC (Ping timeout: 246 seconds) | 07:43 | |
| *** mobius <[email protected]> has joined #yosys | 07:47 | |
| Myrl-saki | Can block RAM be considered as async write? | 07:50 |
| Myrl-saki | Wait, that kind of makes no sense does it | 07:51 |
| lofty | Myrl-saki: you basically never want async write | 08:00 |
| Myrl-saki | Yeah, I kind of had a messup in understanding "async" and "sync" there, but I think I get it now. | 08:01 |
| *** jkm <[email protected]> has joined #yosys | 10:45 | |
| *** jkm <[email protected]> has quit IRC (Ping timeout: 250 seconds) | 11:04 | |
| *** jkm <[email protected]> has joined #yosys | 11:06 | |
| *** lexano <[email protected]> has joined #yosys | 12:57 | |
| *** citypw <citypw!~citypw@gateway/tor-sasl/citypw> has quit IRC (Ping timeout: 240 seconds) | 13:26 | |
| *** nelgau <[email protected]> has quit IRC (Read error: Connection reset by peer) | 13:32 | |
| *** nelgau <[email protected]> has joined #yosys | 13:33 | |
| Myrl-saki | Okay, stupid question, but like | 13:40 |
| Myrl-saki | Am I having a hard time timing, because I'm using BRAM and IO at the same time? And using combinatorial logic between them | 13:40 |
| Myrl-saki | A bit more specific: I'm progressively converting my CPU and peripherals into Wishbone, and it's not going as fast as I expected. This wasn't a problem on the Tang Nano 9K, so I'm surprised that it's a problem on this board. | 13:42 |
| Myrl-saki | Hm, I think the coordinates should reveal if that's the problem, but I don't think it's that. | 13:45 |
| *** cr1901_ is now known as cr1901 | 13:46 | |
| gatecat | somlo: I think https://github.com/YosysHQ/nextpnr/pull/1249, but I haven't actually tested with Python 3.13 | 15:14 |
| somlo | gatecat: thanks, I'll run some tests and report back | 15:34 |
| *** jkm <[email protected]> has quit IRC (Quit: Client closed) | 15:40 | |
| *** jkm <[email protected]> has joined #yosys | 15:43 | |
| *** FabM <FabM!~FabM@armadeus/team/FabM> has quit IRC (Ping timeout: 260 seconds) | 17:47 | |
| *** peeps <peeps!~peepsalot@openscad/peepsalot> has joined #yosys | 18:07 | |
| *** peeps[zen] <peeps[zen]!~peepsalot@openscad/peepsalot> has quit IRC (Remote host closed the connection) | 18:07 | |
| *** jkm <[email protected]> has quit IRC (Quit: Client closed) | 18:48 | |
| *** jkm <[email protected]> has joined #yosys | 20:17 | |
| *** cr1901 <cr1901!~cr1901@2601:8d:8600:226:5021:bd23:1d17:ff62> has quit IRC (Quit: Leaving) | 20:21 | |
| *** cr1901 <cr1901!~cr1901@2601:8d:8600:226:5021:bd23:1d17:ff62> has joined #yosys | 20:23 | |
| *** jkm <[email protected]> has quit IRC (Quit: Client closed) | 23:13 | |
| *** nonchip <[email protected]> has quit IRC (Quit: https://quassel-irc.org - Chat comfortably. Anywhere.) | 23:20 | |
| *** nonchip <[email protected]> has joined #yosys | 23:20 | |
| *** nonchip <[email protected]> has quit IRC (Quit: No Ping reply in 180 seconds.) | 23:53 | |
| *** nonchip <[email protected]> has joined #yosys | 23:54 | |
Generated by irclog2html.py 2.17.2 by Marius Gedminas - find it at https://mg.pov.lt/irclog2html/!