On 5/31/19 5:12 AM, Chris Chiu wrote: > We have 3 laptops which connect the wifi by the same RTL8723BU. > The PCI VID/PID of the wifi chip is 10EC:B720 which is supported. > They have the same problem with the in-kernel rtl8xxxu driver, the > iperf (as a client to an ethernet-connected server) gets ~1Mbps. > Nevertheless, the signal strength is reported as around -40dBm, > which is quite good. From the wireshark capture, the tx rate for each > data and qos data packet is only 1Mbps. Compare to the Realtek driver > at https://github.com/lwfinger/rtl8723bu, the same iperf test gets > ~12Mbps or better. The signal strength is reported similarly around > -40dBm. That's why we want to improve. > > After reading the source code of the rtl8xxxu driver and Realtek's, the > major difference is that Realtek's driver has a watchdog which will keep > monitoring the signal quality and updating the rate mask just like the > rtl8xxxu_gen2_update_rate_mask() does if signal quality changes. > And this kind of watchdog also exists in rtlwifi driver of some specific > chips, ex rtl8192ee, rtl8188ee, rtl8723ae, rtl8821ae...etc. They have > the same member function named dm_watchdog and will invoke the > corresponding dm_refresh_rate_adaptive_mask to adjust the tx rate > mask. > > With this commit, the tx rate of each data and qos data packet will > be 39Mbps (MCS4) with the 0xF00000 as the tx rate mask. The 20th bit > to 23th bit means MCS4 to MCS7. It means that the firmware still picks > the lowest rate from the rate mask and explains why the tx rate of > data and qos data is always lowest 1Mbps because the default rate mask > passed is always 0xFFFFFFF ranges from the basic CCK rate, OFDM rate, > and MCS rate. However, with Realtek's driver, the tx rate observed from > wireshark under the same condition is almost 65Mbps or 72Mbps. > > I believe the firmware of RTL8723BU may need fix. And I think we > can still bring in the dm_watchdog as rtlwifi to improve from the > driver side. Please leave precious comments for my commits and > suggest what I can do better. Or suggest if there's any better idea > to fix this. Thanks. > > Signed-off-by: Chris Chiu <chiu@xxxxxxxxxxxx> I am really pleased to see you're investigating some of these issues, since I've been pretty swamped and not had time to work on this driver for a long time. The firmware should allow for two rate modes, either firmware handled or controlled by the driver. Ideally we would want the driver to handle it, but I never was able to make that work reliable. This fix should at least improve the situation, and it may explain some of the performance issues with the 8192eu as well? > diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h > index 8828baf26e7b..216f603827a8 100644 > --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h > +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h > @@ -1195,6 +1195,44 @@ struct rtl8723bu_c2h { > > struct rtl8xxxu_fileops; > > +/*mlme related.*/ > +enum wireless_mode { > + WIRELESS_MODE_UNKNOWN = 0, > + /* Sub-Element */ > + WIRELESS_MODE_B = BIT(0), > + WIRELESS_MODE_G = BIT(1), > + WIRELESS_MODE_A = BIT(2), > + WIRELESS_MODE_N_24G = BIT(3), > + WIRELESS_MODE_N_5G = BIT(4), > + WIRELESS_AUTO = BIT(5), > + WIRELESS_MODE_AC = BIT(6), > + WIRELESS_MODE_MAX = 0x7F, > +}; > + > +/* from rtlwifi/wifi.h */ > +enum ratr_table_mode_new { > + RATEID_IDX_BGN_40M_2SS = 0, > + RATEID_IDX_BGN_40M_1SS = 1, > + RATEID_IDX_BGN_20M_2SS_BN = 2, > + RATEID_IDX_BGN_20M_1SS_BN = 3, > + RATEID_IDX_GN_N2SS = 4, > + RATEID_IDX_GN_N1SS = 5, > + RATEID_IDX_BG = 6, > + RATEID_IDX_G = 7, > + RATEID_IDX_B = 8, > + RATEID_IDX_VHT_2SS = 9, > + RATEID_IDX_VHT_1SS = 10, > + RATEID_IDX_MIX1 = 11, > + RATEID_IDX_MIX2 = 12, > + RATEID_IDX_VHT_3SS = 13, > + RATEID_IDX_BGN_3SS = 14, > +}; > + > +#define RTL8XXXU_RATR_STA_INIT 0 > +#define RTL8XXXU_RATR_STA_HIGH 1 > +#define RTL8XXXU_RATR_STA_MID 2 > +#define RTL8XXXU_RATR_STA_LOW 3 > + > extern struct rtl8xxxu_fileops rtl8192cu_fops; > extern struct rtl8xxxu_fileops rtl8192eu_fops; > diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c > index 26b674aca125..2071ab9fd001 100644 > --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c > +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c > @@ -1645,6 +1645,148 @@ static void rtl8723bu_init_statistics(struct rtl8xxxu_priv *priv) > rtl8xxxu_write32(priv, REG_OFDM0_FA_RSTC, val32); > } > > +static u8 rtl8723b_signal_to_rssi(int signal) > +{ > + if (signal < -95) > + signal = -95; > + return (u8)(signal + 95); > +} Could you make this more generic so it can be used by the other sub-drivers? > +static void rtl8723b_refresh_rate_mask(struct rtl8xxxu_priv *priv, > + int signal, struct ieee80211_sta *sta) > +{ > + struct ieee80211_hw *hw = priv->hw; > + u16 wireless_mode; > + u8 rssi_level, ratr_idx; > + u8 txbw_40mhz; > + u8 rssi, rssi_thresh_high, rssi_thresh_low; > + > + rssi_level = priv->rssi_level; > + rssi = rtl8723b_signal_to_rssi(signal); > + txbw_40mhz = (hw->conf.chandef.width == NL80211_CHAN_WIDTH_40) ? 1 : 0; > + > + switch (rssi_level) { > + case RTL8XXXU_RATR_STA_HIGH: > + rssi_thresh_high = 50; > + rssi_thresh_low = 20; > + break; > + case RTL8XXXU_RATR_STA_MID: > + rssi_thresh_high = 55; > + rssi_thresh_low = 20; > + break; > + case RTL8XXXU_RATR_STA_LOW: > + rssi_thresh_high = 60; > + rssi_thresh_low = 25; > + break; > + default: > + rssi_thresh_high = 50; > + rssi_thresh_low = 20; > + break; > + } Can we make this use defined values with some explanation rather than hard coded values? > + if (rssi > rssi_thresh_high) > + rssi_level = RTL8XXXU_RATR_STA_HIGH; > + else if (rssi > rssi_thresh_low) > + rssi_level = RTL8XXXU_RATR_STA_MID; > + else > + rssi_level = RTL8XXXU_RATR_STA_LOW; > + > + if (rssi_level != priv->rssi_level) { > + int sgi = 0; > + u32 rate_bitmap = 0; > + > + rcu_read_lock(); > + rate_bitmap = (sta->supp_rates[0] & 0xfff) | > + (sta->ht_cap.mcs.rx_mask[0] << 12) | > + (sta->ht_cap.mcs.rx_mask[1] << 20); > + if (sta->ht_cap.cap & > + (IEEE80211_HT_CAP_SGI_40 | IEEE80211_HT_CAP_SGI_20)) > + sgi = 1; > + rcu_read_unlock(); > + > + wireless_mode = rtl8xxxu_wireless_mode(hw, sta); > + switch (wireless_mode) { > + case WIRELESS_MODE_B: > + ratr_idx = RATEID_IDX_B; > + if (rate_bitmap & 0x0000000c) > + rate_bitmap &= 0x0000000d; > + else > + rate_bitmap &= 0x0000000f; > + break; > + case WIRELESS_MODE_A: > + case WIRELESS_MODE_G: > + ratr_idx = RATEID_IDX_G; > + if (rssi_level == RTL8XXXU_RATR_STA_HIGH) > + rate_bitmap &= 0x00000f00; > + else > + rate_bitmap &= 0x00000ff0; > + break; > + case (WIRELESS_MODE_B | WIRELESS_MODE_G): > + ratr_idx = RATEID_IDX_BG; > + if (rssi_level == RTL8XXXU_RATR_STA_HIGH) > + rate_bitmap &= 0x00000f00; > + else if (rssi_level == RTL8XXXU_RATR_STA_MID) > + rate_bitmap &= 0x00000ff0; > + else > + rate_bitmap &= 0x00000ff5; > + break; It would be nice as well to get all these masks into generic names. > + case WIRELESS_MODE_N_24G: > + case WIRELESS_MODE_N_5G: > + case (WIRELESS_MODE_G | WIRELESS_MODE_N_24G): > + case (WIRELESS_MODE_A | WIRELESS_MODE_N_5G): > + if (priv->tx_paths == 2 && priv->rx_paths == 2) > + ratr_idx = RATEID_IDX_GN_N2SS; > + else > + ratr_idx = RATEID_IDX_GN_N1SS; > + case (WIRELESS_MODE_B | WIRELESS_MODE_G | WIRELESS_MODE_N_24G): > + case (WIRELESS_MODE_B | WIRELESS_MODE_N_24G): > + if (txbw_40mhz) { > + if (priv->tx_paths == 2 && priv->rx_paths == 2) > + ratr_idx = RATEID_IDX_BGN_40M_2SS; > + else > + ratr_idx = RATEID_IDX_BGN_40M_1SS; > + } else { > + if (priv->tx_paths == 2 && priv->rx_paths == 2) > + ratr_idx = RATEID_IDX_BGN_20M_2SS_BN; > + else > + ratr_idx = RATEID_IDX_BGN_20M_1SS_BN; > + } > + > + if (priv->tx_paths == 2 && priv->rx_paths == 2) { > + if (rssi_level == RTL8XXXU_RATR_STA_HIGH) { > + rate_bitmap &= 0x0f8f0000; > + } else if (rssi_level == RTL8XXXU_RATR_STA_MID) { > + rate_bitmap &= 0x0f8ff000; > + } else { > + if (txbw_40mhz) > + rate_bitmap &= 0x0f8ff015; > + else > + rate_bitmap &= 0x0f8ff005; > + } > + } else { > + if (rssi_level == RTL8XXXU_RATR_STA_HIGH) { > + rate_bitmap &= 0x000f0000; > + } else if (rssi_level == RTL8XXXU_RATR_STA_MID) { > + rate_bitmap &= 0x000ff000; > + } else { > + if (txbw_40mhz) > + rate_bitmap &= 0x000ff015; > + else > + rate_bitmap &= 0x000ff005; > + } > + } > + break; > + default: > + ratr_idx = RATEID_IDX_BGN_40M_2SS; > + rate_bitmap &= 0x0fffffff; > + break; > + } > + > + priv->rssi_level = rssi_level; > + priv->fops->update_rate_mask(priv, rate_bitmap, ratr_idx, sgi); > + } > +} > + In general I think all of this should be fairly generic and the other subdrivers should be able to benefit from it? > struct rtl8xxxu_fileops rtl8723bu_fops = { > .parse_efuse = rtl8723bu_parse_efuse, > .load_firmware = rtl8723bu_load_firmware, > @@ -1665,6 +1807,7 @@ struct rtl8xxxu_fileops rtl8723bu_fops = { > .usb_quirks = rtl8xxxu_gen2_usb_quirks, > .set_tx_power = rtl8723b_set_tx_power, > .update_rate_mask = rtl8xxxu_gen2_update_rate_mask, > + .refresh_rate_mask = rtl8723b_refresh_rate_mask, > .report_connect = rtl8xxxu_gen2_report_connect, > .fill_txdesc = rtl8xxxu_fill_txdesc_v2, > .writeN_block_size = 1024, > diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > index 039e5ca9d2e4..be322402ca01 100644 > --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > @@ -4311,7 +4311,8 @@ static void rtl8xxxu_sw_scan_complete(struct ieee80211_hw *hw, > rtl8xxxu_write8(priv, REG_BEACON_CTRL, val8); > } > > -void rtl8xxxu_update_rate_mask(struct rtl8xxxu_priv *priv, u32 ramask, int sgi) > +void rtl8xxxu_update_rate_mask(struct rtl8xxxu_priv *priv, > + u32 ramask, u8 rateid, int sgi) > { > struct h2c_cmd h2c; > > @@ -4331,7 +4332,7 @@ void rtl8xxxu_update_rate_mask(struct rtl8xxxu_priv *priv, u32 ramask, int sgi) > } > > void rtl8xxxu_gen2_update_rate_mask(struct rtl8xxxu_priv *priv, > - u32 ramask, int sgi) > + u32 ramask, u8 rateid, int sgi) > { > struct h2c_cmd h2c; > u8 bw = 0; > @@ -4345,7 +4346,7 @@ void rtl8xxxu_gen2_update_rate_mask(struct rtl8xxxu_priv *priv, > h2c.b_macid_cfg.ramask3 = (ramask >> 24) & 0xff; > > h2c.ramask.arg = 0x80; > - h2c.b_macid_cfg.data1 = 0; > + h2c.b_macid_cfg.data1 = rateid; > if (sgi) > h2c.b_macid_cfg.data1 |= BIT(7); > > @@ -4485,6 +4486,40 @@ static void rtl8xxxu_set_basic_rates(struct rtl8xxxu_priv *priv, u32 rate_cfg) > rtl8xxxu_write8(priv, REG_INIRTS_RATE_SEL, rate_idx); > } > > +u16 > +rtl8xxxu_wireless_mode(struct ieee80211_hw *hw, struct ieee80211_sta *sta) > +{ > + u16 network_type = WIRELESS_MODE_UNKNOWN; > + u32 rate_mask; > + > + rate_mask = (sta->supp_rates[0] & 0xfff) | > + (sta->ht_cap.mcs.rx_mask[0] << 12) | > + (sta->ht_cap.mcs.rx_mask[0] << 20); > + > + if (hw->conf.chandef.chan->band == NL80211_BAND_5GHZ) { > + if (sta->vht_cap.vht_supported) > + network_type = WIRELESS_MODE_AC; > + else if (sta->ht_cap.ht_supported) > + network_type = WIRELESS_MODE_N_5G; > + > + network_type |= WIRELESS_MODE_A; > + } else { > + if (sta->vht_cap.vht_supported) > + network_type = WIRELESS_MODE_AC; > + else if (sta->ht_cap.ht_supported) > + network_type = WIRELESS_MODE_N_24G; > + > + if (sta->supp_rates[0] <= 0xf) > + network_type |= WIRELESS_MODE_B; > + else if (sta->supp_rates[0] & 0xf) > + network_type |= (WIRELESS_MODE_B | WIRELESS_MODE_G); > + else > + network_type |= WIRELESS_MODE_G; > + } > + > + return network_type; > +} I always hated the wireless_mode nonsense in the realtek driver, but maybe we cannot avoid it :( Cheers, Jes
