Re: [PATCH net] wifi: ath12k: properly set single_chip_mlo_supp to true in ath12k_core_alloc()

[Dmitry Baryshkov]

On Wed, Mar 19, 2025 at 11:00:34AM +0100, neil.armstrong@xxxxxxxxxx wrote:
> Hi,
> 
> On 19/03/2025 10:46, Baochen Qiang wrote:
> > 
> > 
> > On 3/19/2025 5:12 PM, neil.armstrong@xxxxxxxxxx wrote:
> > > Hi,
> > > 
> > > On 19/03/2025 10:06, Vasanthakumar Thiagarajan wrote:
> > > > 
> > > > 
> > > > On 3/19/2025 1:34 PM, Neil Armstrong wrote:
> > > > > On 18/03/2025 17:35, Jeff Johnson wrote:
> > > > > > On 3/3/2025 7:00 AM, Neil Armstrong wrote:
> > > > > > > In commit 46d16f7e1d14 ("wifi: ath12k: rename mlo_capable_flags to
> > > > > > > single_chip_mlo_supp")
> > > > > > > the line:
> > > > > > >      ab->mlo_capable_flags = ATH12K_INTRA_DEVICE_MLO_SUPPORT;
> > > > > > > was incorrectly updated to:
> > > > > > >      ab->single_chip_mlo_supp = false;
> > > > > > > leading to always disabling INTRA_DEVICE_MLO even if the device supports it.
> > > > > > > 
> > > > > > > The firmware "WLAN.HMT.1.1.c5-00156-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1"
> > > > > > > crashes on driver initialization with:
> > > > > > >    ath12k_pci 0000:01:00.0: chip_id 0x2 chip_family 0x4 board_id 0x3d soc_id 0x40170200
> > > > > > >    ath12k_pci 0000:01:00.0: fw_version 0x110f009c fw_build_timestamp 2024-05-30 11:35
> > > > > > > fw_build_id QC_IMAGE_VERSION_STRING=WLAN.HMT.1.1.c5-00156-
> > > > > > > QCAHMTSWPL_V1.0_V2.0_SILICONZ-1
> > 
> > this FW version is not upstream yet, why are you testing with it?
> 
> I was not aware the driver supported only a small subset of firmwares.
> 
> > 
> > Generally we only support upstrmea driver + upstream FW.
> 
> In this case, change the driver to only support those exact firmware versions,
> or print a warning in case we try to load a non-mainline-supported firmware.
> 
> But if you did read the commit message, the commit 46d16f7e1d14 is bogus, the
> single_chip_mlo_supp should be set to true to keep the driver behavior prior
> of commit 46d16f7e1d14. It happens to trigger the crash with this firmware,
> but the code behavior was changed by commit 46d16f7e1d14, which should be fixed.

Now to the change itself. I have checked the referened commit. It's
behaviour doesn't match commit message. It tells: "For the WCN7850
family of chipsets, since the event is not supported, assumption is made
that single chip MLO is supported.", however the contents of the commit
doesn't match this. As such, I'd support the patch, it looks corect to
me, despite being used with the non-supported firmware.

> This is the whole point of this patch, fix a regression on the mainline tree
> for existing users.

-- 
With best wishes
Dmitry