wifi: mt76: mt7915: improve accuracy of time_busy calculation

The MIB INFO command is fetching MIB_BUSY_TIME, MIB_TX_TIME, MIB_RX_TIME and
MIB_OBSS_AIRTIME from the radio and filling out cc_busy, cc_tx, cc_bss_rx
and cc_rx respectively.

busy should be >= tx + rx >= tx + bss_rx but we don’t always quite see this.
Sometimes tx + rx is a bit higher than busy due to inaccurate accounting,
so this patch recalculates numbers to make them more reasonable.

Reported-By: Kevin Schneider <kevin.schneider@adtran.com>
Tested-by: Kevin Schneider <kevin.schneider@adtran.com>
Tested-by: Chad Monroe <chad.monroe@smartrg.com>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/init.c b/drivers/net/wireless/mediatek/mt76/mt7915/init.c
index 324db52..e864c0a 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7915/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/init.c
@@ -444,6 +444,23 @@ mt7915_mac_init_band(struct mt7915_dev *dev, u8 band)
 
        /* mt7915: disable rx rate report by default due to hw issues */
        mt76_clear(dev, MT_DMA_DCR0(band), MT_DMA_DCR0_RXD_G5_EN);
+
+       /* clear estimated value of EIFS for Rx duration & OBSS time */
+       mt76_wr(dev, MT_WF_RMAC_RSVD0(band), MT_WF_RMAC_RSVD0_EIFS_CLR);
+
+       /* clear backoff time for Rx duration  */
+       mt76_clear(dev, MT_WF_RMAC_MIB_AIRTIME1(band),
+                  MT_WF_RMAC_MIB_NONQOSD_BACKOFF);
+       mt76_clear(dev, MT_WF_RMAC_MIB_AIRTIME3(band),
+                  MT_WF_RMAC_MIB_QOS01_BACKOFF);
+       mt76_clear(dev, MT_WF_RMAC_MIB_AIRTIME4(band),
+                  MT_WF_RMAC_MIB_QOS23_BACKOFF);
+
+       /* clear backoff time and set software compensation for OBSS time */
+       mask = MT_WF_RMAC_MIB_OBSS_BACKOFF | MT_WF_RMAC_MIB_ED_OFFSET;
+       set = FIELD_PREP(MT_WF_RMAC_MIB_OBSS_BACKOFF, 0) |
+             FIELD_PREP(MT_WF_RMAC_MIB_ED_OFFSET, 4);
+       mt76_rmw(dev, MT_WF_RMAC_MIB_AIRTIME0(band), mask, set);
 }
 
 static void mt7915_mac_init(struct mt7915_dev *dev)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
index 790d690..4000fcd 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
@@ -2940,25 +2940,36 @@ int mt7915_mcu_get_chan_mib_info(struct mt7915_phy *phy, bool chan_switch)
 {
        /* strict order */
        static const u32 offs[] = {
-               MIB_BUSY_TIME, MIB_TX_TIME, MIB_RX_TIME, MIB_OBSS_AIRTIME,
-               MIB_BUSY_TIME_V2, MIB_TX_TIME_V2, MIB_RX_TIME_V2,
+               MIB_NON_WIFI_TIME,
+               MIB_TX_TIME,
+               MIB_RX_TIME,
+               MIB_OBSS_AIRTIME,
+               MIB_TXOP_INIT_COUNT,
+               /* v2 */
+               MIB_NON_WIFI_TIME_V2,
+               MIB_TX_TIME_V2,
+               MIB_RX_TIME_V2,
                MIB_OBSS_AIRTIME_V2
        };
        struct mt76_channel_state *state = phy->mt76->chan_state;
        struct mt76_channel_state *state_ts = &phy->state_ts;
        struct mt7915_dev *dev = phy->dev;
-       struct mt7915_mcu_mib *res, req[4];
+       struct mt7915_mcu_mib *res, req[5];
        struct sk_buff *skb;
        int i, ret, start = 0, ofs = 20;
+       u64 cc_tx;
 
        if (!is_mt7915(&dev->mt76)) {
-               start = 4;
+               start = 5;
                ofs = 0;
        }
 
-       for (i = 0; i < 4; i++) {
+       for (i = 0; i < 5; i++) {
                req[i].band = cpu_to_le32(phy != &dev->phy);
                req[i].offs = cpu_to_le32(offs[i + start]);
+
+               if (!is_mt7915(&dev->mt76) && i == 3)
+                       break;
        }
 
        ret = mt76_mcu_send_and_get_msg(&dev->mt76, MCU_EXT_CMD(GET_MIB_INFO),
@@ -2968,20 +2979,24 @@ int mt7915_mcu_get_chan_mib_info(struct mt7915_phy *phy, bool chan_switch)
 
        res = (struct mt7915_mcu_mib *)(skb->data + ofs);
 
+#define __res_u64(s) le64_to_cpu(res[s].data)
+       /* subtract Tx backoff time from Tx duration */
+       cc_tx = is_mt7915(&dev->mt76) ? __res_u64(1) - __res_u64(4) : __res_u64(1);
+
        if (chan_switch)
                goto out;
 
-#define __res_u64(s) le64_to_cpu(res[s].data)
-       state->cc_busy += __res_u64(0) - state_ts->cc_busy;
-       state->cc_tx += __res_u64(1) - state_ts->cc_tx;
+       state->cc_tx += cc_tx - state_ts->cc_tx;
        state->cc_bss_rx += __res_u64(2) - state_ts->cc_bss_rx;
        state->cc_rx += __res_u64(2) + __res_u64(3) - state_ts->cc_rx;
+       state->cc_busy += __res_u64(0) + cc_tx + __res_u64(2) + __res_u64(3) -
+                         state_ts->cc_busy;
 
 out:
-       state_ts->cc_busy = __res_u64(0);
-       state_ts->cc_tx = __res_u64(1);
+       state_ts->cc_tx = cc_tx;
        state_ts->cc_bss_rx = __res_u64(2);
        state_ts->cc_rx = __res_u64(2) + __res_u64(3);
+       state_ts->cc_busy = __res_u64(0) + cc_tx + __res_u64(2) + __res_u64(3);
 #undef __res_u64
 
        dev_kfree_skb(skb);

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.h b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.h
index 87cd1bf..a4f903f 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.h
@@ -160,15 +160,17 @@ struct mt7915_mcu_mib {
 
 enum mt7915_chan_mib_offs {
        /* mt7915 */
-       MIB_BUSY_TIME = 14,
        MIB_TX_TIME = 81,
        MIB_RX_TIME,
        MIB_OBSS_AIRTIME = 86,
+       MIB_NON_WIFI_TIME,
+       MIB_TXOP_INIT_COUNT,
+
        /* mt7916 */
-       MIB_BUSY_TIME_V2 = 0,
        MIB_TX_TIME_V2 = 6,
        MIB_RX_TIME_V2 = 8,
-       MIB_OBSS_AIRTIME_V2 = 490
+       MIB_OBSS_AIRTIME_V2 = 490,
+       MIB_NON_WIFI_TIME_V2
 };
 
 struct edca {

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/regs.h b/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
index 5180dd9..7db8096 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
@@ -525,8 +525,22 @@ enum offs_rev {
 #define MT_WF_RFCR1_DROP_CFEND         BIT(7)
 #define MT_WF_RFCR1_DROP_CFACK         BIT(8)
 
+#define MT_WF_RMAC_RSVD0(_band)        MT_WF_RMAC(_band, 0x02e0)
+#define MT_WF_RMAC_RSVD0_EIFS_CLR      BIT(21)
+
 #define MT_WF_RMAC_MIB_AIRTIME0(_band) MT_WF_RMAC(_band, 0x0380)
 #define MT_WF_RMAC_MIB_RXTIME_CLR      BIT(31)
+#define MT_WF_RMAC_MIB_OBSS_BACKOFF    GENMASK(15, 0)
+#define MT_WF_RMAC_MIB_ED_OFFSET       GENMASK(20, 16)
+
+#define MT_WF_RMAC_MIB_AIRTIME1(_band) MT_WF_RMAC(_band, 0x0384)
+#define MT_WF_RMAC_MIB_NONQOSD_BACKOFF GENMASK(31, 16)
+
+#define MT_WF_RMAC_MIB_AIRTIME3(_band) MT_WF_RMAC(_band, 0x038c)
+#define MT_WF_RMAC_MIB_QOS01_BACKOFF   GENMASK(31, 0)
+
+#define MT_WF_RMAC_MIB_AIRTIME4(_band) MT_WF_RMAC(_band, 0x0390)
+#define MT_WF_RMAC_MIB_QOS23_BACKOFF   GENMASK(31, 0)
 
 /* WFDMA0 */
 #define MT_WFDMA0_BASE                 __REG(WFDMA0_ADDR)