Re: [PATCH wireless-next v2 0/5] b43: N-PHY: fix calibrations on rev7+ (BCM43228)

[Alessio Ferri <alessio.ferri@mythread.it>]

Il giorno Fri,  6 Nov 2026 22:15:11 +0100
Luca Casati <luk00casati@gmail.com> ha scritto:

> On a BCM43228 (14e4:4359, N-PHY rev 16, radio 2057 rev 9) b43
> associates but transmits poorly: high retry counts and low rates.
> Comparing mmiotraces of b43 and the proprietary wl driver
> (6.30.223.271) on the same card, together with brcmsmac, turned up
> several bugs in the N-PHY calibration code:
> 
>  1. The TX tone sample table was loaded as all zeros, so every
>     tone-based calibration ran without a signal.
>  2. TX IQ/LO calibration: inverted busy poll, reversed final copy,
>     and missing rev7+ cleanup that left TX dead after a cal.
>  3. RSSI calibration: wrong VCM written on rev7+, wrong distance
>     formula, wrong rounding of negative offsets.
>  4. 2057 RC calibration: every delay was about twice wl's, so the
>     first run was stopped while it was running and SCAP read 0
>     instead of 8, detuning the TX low-pass filter.
>  5. A missing field in the rev7 TX_PU RF override.
> 
> The traces, and excerpts of the operations behind each patch next to
> the same operations from b43, are at:
> 
>   https://github.com/Luca00casati/b43patch/blob/755c2d8/traces/README.md
> 
> Each changelog links its excerpts.
> 
> Patches 4 and 5 and the cleanup parts of patch 2 only affect rev7+.
> Patch 1, the poll and final-copy fixes in patch 2, and the
> distance/rounding fixes in patch 3 also change code that runs on older
> N-PHYs (rev3+); I could only test rev 16, so testing on other N-PHY
> cards would be welcome.
> 
> Tested on the BCM43228 only (2.4 GHz, 11g/HT20), on v7.0; the series
> also applies to wireless-next. With v1, throughput to the internet
> went from about 5.7/4.1 to 11.1/5.2 Mbit/s down/up, with fewer TX
> retries. That number is limited by the line and noisy, so take it as
> a rough indication; wl reaches 21-32 Mbit/s down on the same setup,
> so there is more to do (PAPD and TX power control on rev7+).
> 
> Changelogs refer to wl where the fix was checked against its register
> writes. If citing the proprietary driver is not acceptable here, I am
> happy to reword them.
> 
> The bugs were found and the fixes drafted with the help of an AI
> coding assistant (Claude Opus 5.5), working from the mmiotrace diffs
> between b43 and wl and from brcmsmac. I reviewed and tested every
> patch on the hardware above.
> 
> Changes in v2:
> - Dropped the comments the patches added.
> - Patch 2: the changelog said the coefficients match wl's; they are
>   close, not equal.
> - Patch 4: replaced. v1 waited for the first RC cal run and explained
>   it wrongly: wl stops that run right away too, just sooner. v2 uses
>   wl's delays throughout the cal instead.
> - Linked the mmiotrace excerpts from each changelog.
> 
> Luca Casati (5):
>   b43: N-PHY: fix the TX tone sample table
>   b43: N-PHY: fix TX IQ/LO calibration
>   b43: N-PHY: fix rev3+ RSSI calibration
>   b43: N-PHY: use wl's delays in the 2057 RC calibration
>   b43: N-PHY: add the missing override to the rev7 TX_PU command
> 
>  drivers/net/wireless/broadcom/b43/phy_n.c | 115
> +++++++++++++++++----- 1 file changed, 90 insertions(+), 25
> deletions(-)
> 
> 
> base-commit: 028ef9c96e96197026887c0f092424679298aae8

You didn't use check the maintainers right? Because you keep including
Arend...

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