[PATCH mt76] wifi: mt76: mt7915: configure noise floor reporting on reset

[PATCH mt76] wifi: mt76: mt7915: configure noise floor reporting on reset

[David Bauer]

When performing a full system recovery of the MCU on a dual-phy
platform, band 0 (usually 2.4GHz) stops reading correct noise floor
data.

This is due to noise floor reporting only being configured correctly
for the second device PHY.

Configure the respective registers correctly after restarting the MCU
firmware to fix reported noise-floor values.

Signed-off-by: David Bauer <mail@david-bauer.net>
---
 drivers/net/wireless/mediatek/mt76/mt7915/main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/main.c b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
index e1d83052aa6dd..b42c26d0d09a4 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
@@ -25,11 +25,13 @@ int mt7915_run(struct ieee80211_hw *hw)
 	struct mt7915_dev *dev = mt7915_hw_dev(hw);
 	struct mt7915_phy *phy = mt7915_hw_phy(hw);
 	bool running;
+	bool reset;
 	int ret;
 
 	running = mt7915_dev_running(dev);
+	reset = test_bit(MT76_RESET, &phy->mt76->state);
 
-	if (!running) {
+	if (!running || (reset && phy == &dev->phy)) {
 		ret = mt76_connac_mcu_set_pm(&dev->mt76,
 					     dev->phy.mt76->band_idx, 0);
 		if (ret)
-- 
2.53.0

Re: [PATCH mt76] wifi: mt76: mt7915: configure noise floor reporting on reset

[Felix Fietkau]

On 16.05.26 16:49, David Bauer wrote:
> When performing a full system recovery of the MCU on a dual-phy
> platform, band 0 (usually 2.4GHz) stops reading correct noise floor
> data.
> 
> This is due to noise floor reporting only being configured correctly
> for the second device PHY.
> 
> Configure the respective registers correctly after restarting the MCU
> firmware to fix reported noise-floor values.
> 
> Signed-off-by: David Bauer <mail@david-bauer.net>
Have you considered clearing MT76_STATE_RUNNING in mt7915_mac_restart 
instead?

- Felix

Re: [PATCH mt76] wifi: mt76: mt7915: configure noise floor reporting on reset

[David Bauer]

Hi Felix,

On 5/27/26 15:56, Felix Fietkau wrote:
> On 16.05.26 16:49, David Bauer wrote:
>> When performing a full system recovery of the MCU on a dual-phy
>> platform, band 0 (usually 2.4GHz) stops reading correct noise floor
>> data.
>>
>> This is due to noise floor reporting only being configured correctly
>> for the second device PHY.
>>
>> Configure the respective registers correctly after restarting the MCU
>> firmware to fix reported noise-floor values.
>>
>> Signed-off-by: David Bauer <mail@david-bauer.net>
> Have you considered clearing MT76_STATE_RUNNING in mt7915_mac_restart instead?

The call to mt7915_run is guarded by MT76_STATE_RUNNING being set per-phy.

I think this is to not start the second PHY in case it was never started due to
it not being present. We could in theory remove this check for the primary PHY
and clear the flag prior calling mt7915_run.

This seems a bit more hacky to me. Alternatively I can also refactor the entire
mechanism to make it easier to understand and resolve this indirection in the
process.

What do you think?

Best
David

> 
> - Felix

Re: [PATCH mt76] wifi: mt76: mt7915: configure noise floor reporting on reset

[Felix Fietkau]

On 27.05.26 19:05, David Bauer wrote:
> Hi Felix,
> 
> On 5/27/26 15:56, Felix Fietkau wrote:
>> On 16.05.26 16:49, David Bauer wrote:
>>> When performing a full system recovery of the MCU on a dual-phy
>>> platform, band 0 (usually 2.4GHz) stops reading correct noise floor
>>> data.
>>>
>>> This is due to noise floor reporting only being configured correctly
>>> for the second device PHY.
>>>
>>> Configure the respective registers correctly after restarting the MCU
>>> firmware to fix reported noise-floor values.
>>>
>>> Signed-off-by: David Bauer <mail@david-bauer.net>
>> Have you considered clearing MT76_STATE_RUNNING in mt7915_mac_restart instead?
> 
> The call to mt7915_run is guarded by MT76_STATE_RUNNING being set per-phy.
> 
> I think this is to not start the second PHY in case it was never started due to
> it not being present. We could in theory remove this check for the primary PHY
> and clear the flag prior calling mt7915_run.
> 
> This seems a bit more hacky to me. Alternatively I can also refactor the entire
> mechanism to make it easier to understand and resolve this indirection in the
> process.
My suggestion would be to do this:
start_main = test_and_clear_bit(MT76_STATE_RUNNING, &dev->mphy.state);
start_ext = ext_phy &&
             test_and_clear_bit(MT76_STATE_RUNNING, &ext_phy->state);

Then using those as conditions for calling mt7915_run in 
mt7915_mac_restart.

That way the special case in mt7915_run disappears and the behavior 
becomes easier to follow.

- Felix