Re: [PATCH] wifi: ath12k: fix tx power, max reg power update to firmware

Nicolas Escande
2024-09-20T07:15:57Z

On Fri Sep 20, 2024 at 6:43 AM CEST, Santhosh Ramesh wrote:
[...]
> >
> >> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> >> index 137394c36460..6d7a005d83b4 100644
> >> --- a/drivers/net/wireless/ath/ath12k/mac.c
> >> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> >> @@ -7217,9 +7217,9 @@ ath12k_mac_vdev_start_restart(struct ath12k_vif *arvif,
> >> chandef->chan->band,
> >> arvif->vif->type);
> >> arg.min_power = 0;
> >> - arg.max_power = chandef->chan->max_power * 2;
> >> - arg.max_reg_power = chandef->chan->max_reg_power * 2;
> >> - arg.max_antenna_gain = chandef->chan->max_antenna_gain * 2;
> >> + arg.max_power = chandef->chan->max_power;
> >> + arg.max_reg_power = chandef->chan->max_reg_power;
> >> + arg.max_antenna_gain = chandef->chan->max_antenna_gain;
> >>
> >
> > For what it's worth, I already got a similar patch from QCA a few month ago, and
> > it fixed some tx power problems when scanning so I know there is truth in this.
> >
> >> arg.pref_tx_streams = ar->num_tx_chains;
> >> arg.pref_rx_streams = ar->num_rx_chains;
> >>
> >> base-commit: 903aaf66edc97dd5b9e3118d19677291051a9c40
> >
> > But there also was more in the patch:
> >
> > diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c
> > index a97e1399eeed..87e3ae49afa5 100644
> > --- a/drivers/net/wireless/ath/ath12k/wmi.c
> > +++ b/drivers/net/wireless/ath/ath12k/wmi.c
> > @@ -2563,6 +2563,8 @@ int ath12k_wmi_send_scan_chan_list_cmd(struct ath12k *ar,
> > WMI_CHAN_REG_INFO1_REG_CLS);
> > *reg2 |= le32_encode_bits(channel_arg->antennamax,
> > WMI_CHAN_REG_INFO2_ANT_MAX);
> > + *reg2 |= le32_encode_bits(channel_arg->maxregpower,
> > + WMI_CHAN_REG_INFO2_MAX_TX_PWR);
> >
> > ath12k_dbg(ar->ab, ATH12K_DBG_WMI,
> > "WMI chan scan list chan[%d] = %u, chan_info->info %8x\n",
> >
> > It seems that ath11k has a similar piece of code in the equivalent function
> > ath11k_wmi_send_scan_chan_list_cmd . Isn't this needed ?
>
> This change is in a separate patch, which will be sent for public review soon.

OK

>
> >
> > Also I see that in ath12k/reg.c in ath12k_reg_update_chan_list we also send to
> > the firmware:
> > ch->maxpower = channel->max_power * 2;
> > ch->maxregpower = channel->max_reg_power * 2;
> > ch->antennamax = channel->max_antenna_gain * 2;
> >
> > As it is in a different wmi message, I guess the units are different. 0.5 dBm
> > increment in struct ath12k_wmi_channel_arg right ? Or should we remove the '*2'
> >
>
> Yes, the firmware expects these values in 0.5 dBm increments, so we multiply
> them by 2 in the ath12k_reg_update_chan_list function.
Good

Then good news this gets mainlined by the way, but it's a shame it takes this
long (like 10 months or so...)

Reviewed-by: Nicolas Escande <nico.escande@gmail.com>