| Message ID | 20180621091801.41184-1-nbd@nbd.name (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | aea38272920c227865af25c7d7710f1ab0d8a1ce |
| Delegated to: | Kalle Valo |
| Headers | show |
Felix Fietkau <nbd@nbd.name> wrote: > The beacon timer drifts by 1 microsecond every TBTT. After 20 minutes > with a beacon interval of 100, the drift will be almost 12 ms, enough to > cause weird issues for devices in powersave mode. > > Since the beacon timer is configured in units of 1/16 TU (64 us), we > need to adjust it once every 64 beacons and only for one beacon. > > Signed-off-by: Felix Fietkau <nbd@nbd.name> 9 patches applied to wireless-drivers-next.git, thanks. aea38272920c mt76: fix beacon timer drift 9afef0fddaa1 mt76: fix threshold for gain adjustment 6cdb9614a818 mt76: fix swapped values for RXO-18 in gain control 929211687197 mt76: adjust AGC control register 26 based on gain for VHT80 fa967b586031 mt76: clear false CCA counters after changing gain settings 8e31f0d35a88 mt76: fix variable gain adjustment range 108ec4dafd61 mt76: add a debugfs file to dump agc calibration information 32e49efe0f15 mt76: track ewma rssi for gain adjustment per station c3ae2103e069 mt76: improve gain adjustment in noisy environments
diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2.h b/drivers/net/wireless/mediatek/mt76/mt76x2.h index dc12bbdbb2ee..06ca5a77dfdf 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2.h +++ b/drivers/net/wireless/mediatek/mt76/mt76x2.h @@ -120,10 +120,13 @@ struct mt76x2_dev { u8 beacon_mask; u8 beacon_data_mask; - u32 rxfilter; + u8 tbtt_count; + u16 beacon_int; u16 chainmask; + u32 rxfilter; + struct mt76x2_calibration cal; s8 target_power; diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c index ce90ff999b49..e4e41faf6739 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c @@ -238,10 +238,13 @@ mt76x2_bss_info_changed(struct ieee80211_hw *hw, struct ieee80211_vif *vif, if (changed & BSS_CHANGED_BSSID) mt76x2_mac_set_bssid(dev, mvif->idx, info->bssid); - if (changed & BSS_CHANGED_BEACON_INT) + if (changed & BSS_CHANGED_BEACON_INT) { mt76_rmw_field(dev, MT_BEACON_TIME_CFG, MT_BEACON_TIME_CFG_INTVAL, info->beacon_int << 4); + dev->beacon_int = info->beacon_int; + dev->tbtt_count = 0; + } if (changed & BSS_CHANGED_BEACON_ENABLED) { tasklet_disable(&dev->pre_tbtt_tasklet); diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c b/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c index e46eafc4c436..560376dd1133 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c @@ -218,6 +218,37 @@ mt76x2_add_buffered_bc(void *priv, u8 *mac, struct ieee80211_vif *vif) data->tail[mvif->idx] = skb; } +static void +mt76x2_resync_beacon_timer(struct mt76x2_dev *dev) +{ + u32 timer_val = dev->beacon_int << 4; + + dev->tbtt_count++; + + /* + * Beacon timer drifts by 1us every tick, the timer is configured + * in 1/16 TU (64us) units. + */ + if (dev->tbtt_count < 62) + return; + + if (dev->tbtt_count >= 64) { + dev->tbtt_count = 0; + return; + } + + /* + * The updated beacon interval takes effect after two TBTT, because + * at this point the original interval has already been loaded into + * the next TBTT_TIMER value + */ + if (dev->tbtt_count == 62) + timer_val -= 1; + + mt76_rmw_field(dev, MT_BEACON_TIME_CFG, + MT_BEACON_TIME_CFG_INTVAL, timer_val); +} + void mt76x2_pre_tbtt_tasklet(unsigned long arg) { struct mt76x2_dev *dev = (struct mt76x2_dev *) arg; @@ -226,6 +257,8 @@ void mt76x2_pre_tbtt_tasklet(unsigned long arg) struct sk_buff *skb; int i, nframes; + mt76x2_resync_beacon_timer(dev); + data.dev = dev; __skb_queue_head_init(&data.q);
The beacon timer drifts by 1 microsecond every TBTT. After 20 minutes with a beacon interval of 100, the drift will be almost 12 ms, enough to cause weird issues for devices in powersave mode. Since the beacon timer is configured in units of 1/16 TU (64 us), we need to adjust it once every 64 beacons and only for one beacon. Signed-off-by: Felix Fietkau <nbd@nbd.name> --- drivers/net/wireless/mediatek/mt76/mt76x2.h | 5 ++- .../net/wireless/mediatek/mt76/mt76x2_main.c | 5 ++- .../net/wireless/mediatek/mt76/mt76x2_tx.c | 33 +++++++++++++++++++ 3 files changed, 41 insertions(+), 2 deletions(-)