Re: [PATCH ath-next] wifi: ath12k: change MAC buffer ring size to 4096

[Shawn Guo <shengchao.guo@oss.qualcomm.com>]

On Thu, Oct 22, 2026 at 07:00:31PM +0800, Baochen Qiang wrote:
> 
> 
> On 10/22/2026 5:20 PM, Shawn Guo wrote:
> > On Thu, Oct 22, 2026 at 10:30:45AM +0800, Baochen Qiang wrote:
> >>
> >>
> >> On 10/20/2026 4:53 PM, Shawn Guo wrote:
> >>> + linux-arm-msm
> >>>
> >>> On Tue, Jun 09, 2026 at 08:13:58PM -0700, Yingying Tang wrote:
> >>>> For WCN7850, MAC buffer ring size is updated to 2048 in
> >>>> 955df16f2a4c3 ("wifi: ath12k: change MAC buffer ring size to 2048")
> >>>> to increase peak throughput.
> >>>>
> >>>> But during the RX process, a phenomenon can still be observed where
> >>>> the throughput drops by about 30% from its peak value and then recovers,
> >>>> and this behavior repeats during RX.
> >>>>
> >>>> After increasing MAC buffer ring size to 4096, the data rate drop has
> >>>> gone.
> >>>>
> >>>> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3
> >>>>
> >>>> Signed-off-by: Yingying Tang <yingying.tang@oss.qualcomm.com>
> >>>
> >>> FYI, in case someone else runs into this: with this change (merged in
> >>> v7.3), WiFi on my Lenovo Yoga Slim 7x (X1E80100, WCN7850 hw2.0) stopped
> >>> working with the older firmware that Debian trixie still ships
> >>> (firmware-atheros 20250410-2):
> >>>
> >>>   WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
> >>>
> >>> Probe and firmware download succeed, but every WMI command times out
> >>> once the interface is brought up:
> >>>
> >>>   ath12k_wifi7_pci 0004:01:00.0: wmi command 16387 timeout
> >>>   ath12k_wifi7_pci 0004:01:00.0: failed to send WMI_PDEV_SET_PARAM cmd
> >>>   ath12k_wifi7_pci 0004:01:00.0: failed to enable PMF QOS: -11
> >>>   ath12k_wifi7_pci 0004:01:00.0: fail to start mac operations in pdev idx 0 ret -11
> >>>
> >>> Bisecting ath12k between v7.2 and v7.3 lands on this commit, and
> >>> reverting it on v7.3 brings WiFi back with the old firmware.
> >>>
> >>> Unmodified v7.3 works fine after updating to the current linux-firmware
> >>> image:
> >>>
> >>>   WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3
> >>>
> >>> On Debian trixie that one is available from trixie-backports
> >>> (firmware-atheros 20260916-1~bpo13+1).
> >>>
> >>> So nothing needs fixing on the driver side. I'm just leaving this here
> >>> so that anyone who sees "wmi command ... timeout" on WCN7850 after a
> >>> kernel upgrade knows to update the firmware first.
> >>
> >> Hi Shawn, thanks for reporting this. I just had a quick test
> >> WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 with the latest ath tree
> >> (ath-202610191908), everything looks good, simple connection and ping pass, I don't see
> >> any ath12k warning.
> >>
> >> The firmware images I am using comes from the first commit adding WCN7850 firmware:
> >>
> >> 	fb04a7f4b750 ("ath12k: add new driver and firmware for WCN7850")
> >>
> >> and the md5 values are:
> >>
> >> linux-firmware/ath12k/WCN7850/hw2.0$ md5sum ./*
> >> d3750b67b1013fe82358d0538fb131b0  ./amss.bin
> >> c79c410d585360000c0490f16fda43e2  ./board-2.bin
> >> 73056f1d2aff886ce9bff313f455e963  ./m3.bin
> >> d0ee61498bf1a205147cdbcf645391e7  ./Notice.txt
> >>
> >> can you share the md5 values of your images?
> > 
> > Hi Baochen,
> > 
> > Here are md5 values of the old firmware shipped by trixie firmware-atheros
> > 20250410-2.
> > 
> > $ md5sum /lib/firmware/ath12k/WCN7850/hw2.0/*
> > d3750b67b1013fe82358d0538fb131b0  /lib/firmware/ath12k/WCN7850/hw2.0/amss.bin
> > 5dacdfbe6c3c25d9e0605be8a9f1f6e4  /lib/firmware/ath12k/WCN7850/hw2.0/board-2.bin
> 
> this is different from mine, can you try mine?

Are you sure this board file works for my Lenovo Yoga Slim 7x laptop?

> 
> > 73056f1d2aff886ce9bff313f455e963  /lib/firmware/ath12k/WCN7850/hw2.0/m3.bin
> > 
> >> and have you ever tried the upstream mainline
> >> kernel or the latest ath.git tree?
> > 
> > I'm not sure what you mean by upstream mainline kernel, but v7.3 should
> 
> I mean Linus's tree
> 
> > be the mainline kernel released a few days ago.
> > 
> > On the other hand, I just tested ath.git tree at tag ath-202610191908,
> > and it worked with the old firmware. So it seems there are some gaps
> > between v7.3 and ath kernel.
> 
> can you share the exact tag of v7.3 kernel? is it just below tag?

Yes, it is.

Shawn

> 
> commit c03c1a14507dfaf8b856c2608f9ac216021fc222 (tag: v7.3)
> Author: Linus Torvalds <torvalds@linux-foundation.org>
> Date:   Sun Oct 18 13:14:58 2026 -1000
> 
>     Linux 7.3
> 
> diff --git a/Makefile b/Makefile
> index 0dc1a9f4e63e..c61ea07ee505 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -2,7 +2,7 @@
>  VERSION = 7
>  PATCHLEVEL = 3
>  SUBLEVEL = 0
> -EXTRAVERSION = -rc7
> +EXTRAVERSION =
>  NAME = Baby Opossum Posse
> 
>  # *DOCUMENTATION*
> 
> 
> > 
> > Shawn
>