| Message ID | 20210930104422.968365-1-chris.chiu@canonical.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | rtl8xxxu: Use lower tx rates for the ack packet | expand |
On 9/30/21 6:44 AM, Chris Chiu wrote: > According to the Realtek propritary driver and the rtw88 driver, the > tx rates of the ack (includes block ack) are initialized with lower > tx rates (no HT rates) which is set by the RRSR register value. In > real cases, ack rate higher than current tx rate could lead to > difficulty for the receiving end to receive management/control frames. > The retransmission rate would be higher then expected when the driver > is acting as receiver and the RSSI is not good. > > Cross out higer rates for ack packet before implementing dynamic rrsr > configuration Theory of this looks sound to me, but there's an implementation detail, see below. > Signed-off-by: Chris Chiu <chris.chiu@canonical.com> > --- > drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 7 ++++++- > drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h | 2 ++ > 2 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > index 774341b0005a..413cccd88f5c 100644 > --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c > @@ -4460,13 +4460,18 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv) > > static void rtl8xxxu_set_basic_rates(struct rtl8xxxu_priv *priv, u32 rate_cfg) > { > + struct ieee80211_hw *hw = priv->hw; > u32 val32; > u8 rate_idx = 0; > > rate_cfg &= RESPONSE_RATE_BITMAP_ALL; > > val32 = rtl8xxxu_read32(priv, REG_RESPONSE_RATE_SET); > - val32 &= ~RESPONSE_RATE_BITMAP_ALL; > + val32 = rtl8xxxu_read32(priv, REG_RESPONSE_RATE_SET); You're reading REG_RESPONSE_RATE_SET twice. Cheers, Jes
diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c index 774341b0005a..413cccd88f5c 100644 --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c @@ -4460,13 +4460,18 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv) static void rtl8xxxu_set_basic_rates(struct rtl8xxxu_priv *priv, u32 rate_cfg) { + struct ieee80211_hw *hw = priv->hw; u32 val32; u8 rate_idx = 0; rate_cfg &= RESPONSE_RATE_BITMAP_ALL; val32 = rtl8xxxu_read32(priv, REG_RESPONSE_RATE_SET); - val32 &= ~RESPONSE_RATE_BITMAP_ALL; + val32 = rtl8xxxu_read32(priv, REG_RESPONSE_RATE_SET); + if (hw->conf.chandef.chan->band == NL80211_BAND_5GHZ) + val32 &= RESPONSE_RATE_RRSR_INIT_5G; + else + val32 &= RESPONSE_RATE_RRSR_INIT_2G; val32 |= rate_cfg; rtl8xxxu_write32(priv, REG_RESPONSE_RATE_SET, val32); diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h index a2a31f374a82..438b65ba9640 100644 --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h @@ -516,6 +516,8 @@ #define REG_RESPONSE_RATE_SET 0x0440 #define RESPONSE_RATE_BITMAP_ALL 0xfffff #define RESPONSE_RATE_RRSR_CCK_ONLY_1M 0xffff1 +#define RESPONSE_RATE_RRSR_INIT_2G 0x15f +#define RESPONSE_RATE_RRSR_INIT_5G 0x150 #define RSR_1M BIT(0) #define RSR_2M BIT(1) #define RSR_5_5M BIT(2)
According to the Realtek propritary driver and the rtw88 driver, the tx rates of the ack (includes block ack) are initialized with lower tx rates (no HT rates) which is set by the RRSR register value. In real cases, ack rate higher than current tx rate could lead to difficulty for the receiving end to receive management/control frames. The retransmission rate would be higher then expected when the driver is acting as receiver and the RSSI is not good. Cross out higer rates for ack packet before implementing dynamic rrsr configuration Signed-off-by: Chris Chiu <chris.chiu@canonical.com> --- drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 7 ++++++- drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h | 2 ++ 2 files changed, 8 insertions(+), 1 deletion(-)