Attention is currently required from: jolly, pespin. fixeria has posted comments on this change. ( https://gerrit.osmocom.org/c/osmo-bts/+/35132?usp=email ) Change subject: Transmit invalid AMR speech blocks instead of dummy FACCH ...................................................................... Patch Set 2: (2 comments) File src/osmo-bts-trx/sched_lchan_tchf.c: https://gerrit.osmocom.org/c/osmo-bts/+/35132/comment/c1f9471e_0c017d04 PS2, Line 541: * - If the channel mode is AMR, transmit a dummy with speech

I'd document here the rationale about "FACCH displaces two speech frames rather than one". This is not specific to TCH/AHS at all, and is already briefly mentioned in the existing code. It's also just one of the reasons; another reason is that some Qualcomm basebands don't seem to like dummy FACCH and report bad RxQual.

So I would be fine with the current state of this patch. https://gerrit.osmocom.org/c/osmo-bts/+/35132/comment/2cc61db2_e210eeb4 PS2, Line 578: dummy_facch:

Maybe moving the GSM48_CMODE_SPEECH_AMR case inside the default with an "if" block is cleaner than a […] Alternatively, we can move generation of dummy FACCH into a `static inline` function (`src/osmo-bts-trx/sched_utils.h` would be a good place for it) and just call it, hoping that the compiler would inline it properly for us.

-- To view, visit https://gerrit.osmocom.org/c/osmo-bts/+/35132?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-bts Gerrit-Branch: master Gerrit-Change-Id: I056f379715c91ad968f198e112d363a9009dc1c3 Gerrit-Change-Number: 35132 Gerrit-PatchSet: 2 Gerrit-Owner: jolly <andreas@eversberg.eu> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: falconia <falcon@freecalypso.org> Gerrit-Reviewer: fixeria <vyanitskiy@sysmocom.de> Gerrit-CC: pespin <pespin@sysmocom.de> Gerrit-Attention: jolly <andreas@eversberg.eu> Gerrit-Attention: pespin <pespin@sysmocom.de> Gerrit-Comment-Date: Mon, 27 Nov 2023 18:13:20 +0000 Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: pespin <pespin@sysmocom.de> Gerrit-MessageType: comment