modify the rssi logic a bit to actually return a useful rssi.

The fullmac firmware doesn't seem to populate a useful rssi indicator
in the RX descriptor, so if one plotted said values, they'd basically
look like garbage.

The reference driver implements a "get current rssi" firmware command
which I guess is really meant for station operation only (as hostap
operation would need rssi per station, not a single firmware read.)

So:

* populate sc_currssi during each calibration run;
* use this in the RX path instead of trying to reconstruct the RSSI
  value and passing it around as a pointer;
* do up a quick hack to map the rssi hardware value to some useful
  signal level;
* the survey results provide an RSSI value between 0..100, so just
  do another quick hack to map it into some usefulish signal level;
* supply a faked noise floor - I haven't yet found how to pull it
  out of the firmware.

The scan results and the station RSSI information is now more useful
for indicating signal strength / distance.

diff --git a/sys/dev/usb/wlan/if_rsu.c b/sys/dev/usb/wlan/if_rsu.c
index c4c6cc957635d8ec86a0de2c781c9f3a22e69438..4fb9d85bee9dd72082d21708ef3add5905280f3b 100644 (file)
--- a/sys/dev/usb/wlan/if_rsu.c
+++ b/sys/dev/usb/wlan/if_rsu.c
@@ -203,17 +203,18 @@ static void       rsu_delete_key(struct rsu_softc *, const struct ieee80211_key *);
 static int     rsu_site_survey(struct rsu_softc *, struct ieee80211vap *);
 static int     rsu_join_bss(struct rsu_softc *, struct ieee80211_node *);
 static int     rsu_disconnect(struct rsu_softc *);
+static int     rsu_hwrssi_to_rssi(struct rsu_softc *, int hw_rssi);
 static void    rsu_event_survey(struct rsu_softc *, uint8_t *, int);
 static void    rsu_event_join_bss(struct rsu_softc *, uint8_t *, int);
 static void    rsu_rx_event(struct rsu_softc *, uint8_t, uint8_t *, int);
 static void    rsu_rx_multi_event(struct rsu_softc *, uint8_t *, int);
+#if 0
 static int8_t  rsu_get_rssi(struct rsu_softc *, int, void *);
+#endif
+static struct mbuf * rsu_rx_frame(struct rsu_softc *, uint8_t *, int);
+static struct mbuf * rsu_rx_multi_frame(struct rsu_softc *, uint8_t *, int);
 static struct mbuf *
-               rsu_rx_frame(struct rsu_softc *, uint8_t *, int, int *);
-static struct mbuf *
-               rsu_rx_multi_frame(struct rsu_softc *, uint8_t *, int, int *);
-static struct mbuf *
-               rsu_rxeof(struct usb_xfer *, struct rsu_data *, int *);
+               rsu_rxeof(struct usb_xfer *, struct rsu_data *);
 static void    rsu_txeof(struct usb_xfer *, struct rsu_data *);
 static int     rsu_raw_xmit(struct ieee80211_node *, struct mbuf *, 
                    const struct ieee80211_bpf_params *);
@@ -1082,7 +1083,9 @@ static void
 rsu_calib_task(void *arg, int pending __unused)
 {
        struct rsu_softc *sc = arg;
+#ifdef notyet
        uint32_t reg;
+#endif
 
        RSU_DPRINTF(sc, RSU_DEBUG_CALIB, "%s: running calibration task\n",
            __func__);
@@ -1100,9 +1103,10 @@ rsu_calib_task(void *arg, int pending __unused)
 #endif
        /* Read current signal level. */
        if (rsu_fw_iocmd(sc, 0xf4000001) == 0) {
-               reg = rsu_read_4(sc, R92S_IOCMD_DATA);
-               RSU_DPRINTF(sc, RSU_DEBUG_CALIB, "%s: RSSI=%d%%\n",
-                   __func__, reg >> 4);
+               sc->sc_currssi = rsu_read_4(sc, R92S_IOCMD_DATA);
+               RSU_DPRINTF(sc, RSU_DEBUG_CALIB, "%s: RSSI=%d (%d)\n",
+                   __func__, sc->sc_currssi,
+                   rsu_hwrssi_to_rssi(sc, sc->sc_currssi));
        }
        if (sc->sc_calibrating)
                taskqueue_enqueue_timeout(taskqueue_thread, &sc->calib_task, hz);
@@ -1433,6 +1437,24 @@ rsu_disconnect(struct rsu_softc *sc)
        return (rsu_fw_cmd(sc, R92S_CMD_DISCONNECT, &zero, sizeof(zero)));
 }
 
+/*
+ * Map the hardware provided RSSI value to a signal level.
+ * For the most part it's just something we divide by and cap
+ * so it doesn't overflow the representation by net80211.
+ */
+static int
+rsu_hwrssi_to_rssi(struct rsu_softc *sc, int hw_rssi)
+{
+       int v;
+
+       if (hw_rssi == 0)
+               return (0);
+       v = hw_rssi >> 4;
+       if (v > 80)
+               v = 80;
+       return (v);
+}
+
 static void
 rsu_event_survey(struct rsu_softc *sc, uint8_t *buf, int len)
 {
@@ -1486,8 +1508,9 @@ rsu_event_survey(struct rsu_softc *sc, uint8_t *buf, int len)
        rxs.r_flags |= IEEE80211_R_NF | IEEE80211_R_RSSI;
        rxs.c_ieee = le32toh(bss->config.dsconfig);
        rxs.c_freq = ieee80211_ieee2mhz(rxs.c_ieee, IEEE80211_CHAN_2GHZ);
-       rxs.rssi = le32toh(bss->rssi);
-       rxs.nf = 0; /* XXX */
+       /* This is a number from 0..100; so let's just divide it down a bit */
+       rxs.rssi = le32toh(bss->rssi) / 2;
+       rxs.nf = -96;
 
        /* XXX avoid a LOR */
        RSU_UNLOCK(sc);
@@ -1557,7 +1580,7 @@ rsu_event_addba_req_report(struct rsu_softc *sc, uint8_t *buf, int len)
        if (vap == NULL)
                return;
 
-       device_printf(sc->sc_dev, "%s: mac=%s, tid=%d, ssn=%d\n",
+       RSU_DPRINTF(sc, RSU_DEBUG_AMPDU, "%s: mac=%s, tid=%d, ssn=%d\n",
            __func__,
            ether_sprintf(ba->mac_addr),
            (int) ba->tid,
@@ -1670,6 +1693,7 @@ rsu_rx_multi_event(struct rsu_softc *sc, uint8_t *buf, int len)
        }
 }
 
+#if 0
 static int8_t
 rsu_get_rssi(struct rsu_softc *sc, int rate, void *physt)
 {
@@ -1690,9 +1714,10 @@ rsu_get_rssi(struct rsu_softc *sc, int rate, void *physt)
        }
        return (rssi);
 }
+#endif
 
 static struct mbuf *
-rsu_rx_frame(struct rsu_softc *sc, uint8_t *buf, int pktlen, int *rssi)
+rsu_rx_frame(struct rsu_softc *sc, uint8_t *buf, int pktlen)
 {
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211_frame *wh;
@@ -1718,16 +1743,17 @@ rsu_rx_frame(struct rsu_softc *sc, uint8_t *buf, int pktlen, int *rssi)
        rate = MS(rxdw3, R92S_RXDW3_RATE);
        infosz = MS(rxdw0, R92S_RXDW0_INFOSZ) * 8;
 
+#if 0
        /* Get RSSI from PHY status descriptor if present. */
        if (infosz != 0)
                *rssi = rsu_get_rssi(sc, rate, &stat[1]);
        else
                *rssi = 0;
+#endif
 
        RSU_DPRINTF(sc, RSU_DEBUG_RX,
-           "%s: Rx frame len=%d rate=%d infosz=%d rssi=%d\n",
-           __func__,
-           pktlen, rate, infosz, *rssi);
+           "%s: Rx frame len=%d rate=%d infosz=%d\n",
+           __func__, pktlen, rate, infosz);
 
        m = m_get2(pktlen, M_NOWAIT, MT_DATA, M_PKTHDR);
        if (__predict_false(m == NULL)) {
@@ -1769,7 +1795,11 @@ rsu_rx_frame(struct rsu_softc *sc, uint8_t *buf, int pktlen, int *rssi)
                        /* Bit 7 set means HT MCS instead of rate. */
                        tap->wr_rate = 0x80 | (rate - 12);
                }
+#if 0
                tap->wr_dbm_antsignal = *rssi;
+#endif
+               /* XXX not nice */
+               tap->wr_dbm_antsignal = rsu_hwrssi_to_rssi(sc, sc->sc_currssi);
                tap->wr_chan_freq = htole16(ic->ic_curchan->ic_freq);
                tap->wr_chan_flags = htole16(ic->ic_curchan->ic_flags);
        }
@@ -1778,7 +1808,7 @@ rsu_rx_frame(struct rsu_softc *sc, uint8_t *buf, int pktlen, int *rssi)
 }
 
 static struct mbuf *
-rsu_rx_multi_frame(struct rsu_softc *sc, uint8_t *buf, int len, int *rssi)
+rsu_rx_multi_frame(struct rsu_softc *sc, uint8_t *buf, int len)
 {
        struct r92s_rx_stat *stat;
        uint32_t rxdw0;
@@ -1810,7 +1840,7 @@ rsu_rx_multi_frame(struct rsu_softc *sc, uint8_t *buf, int len, int *rssi)
                        break;
 
                /* Process 802.11 frame. */
-               m = rsu_rx_frame(sc, buf, pktlen, rssi);
+               m = rsu_rx_frame(sc, buf, pktlen);
                if (m0 == NULL)
                        m0 = m;
                if (prevm == NULL)
@@ -1829,7 +1859,7 @@ rsu_rx_multi_frame(struct rsu_softc *sc, uint8_t *buf, int len, int *rssi)
 }
 
 static struct mbuf *
-rsu_rxeof(struct usb_xfer *xfer, struct rsu_data *data, int *rssi)
+rsu_rxeof(struct usb_xfer *xfer, struct rsu_data *data)
 {
        struct rsu_softc *sc = data->sc;
        struct ieee80211com *ic = &sc->sc_ic;
@@ -1850,7 +1880,7 @@ rsu_rxeof(struct usb_xfer *xfer, struct rsu_data *data, int *rssi)
                /* No packets to process. */
                return (NULL);
        } else
-               return (rsu_rx_multi_frame(sc, data->buf, len, rssi));
+               return (rsu_rx_multi_frame(sc, data->buf, len));
 }
 
 static void
@@ -1862,7 +1892,6 @@ rsu_bulk_rx_callback(struct usb_xfer *xfer, usb_error_t error)
        struct ieee80211_node *ni;
        struct mbuf *m = NULL, *next;
        struct rsu_data *data;
-       int rssi = 1;
 
        RSU_ASSERT_LOCKED(sc);
 
@@ -1872,7 +1901,7 @@ rsu_bulk_rx_callback(struct usb_xfer *xfer, usb_error_t error)
                if (data == NULL)
                        goto tr_setup;
                STAILQ_REMOVE_HEAD(&sc->sc_rx_active, next);
-               m = rsu_rxeof(xfer, data, &rssi);
+               m = rsu_rxeof(xfer, data);
                STAILQ_INSERT_TAIL(&sc->sc_rx_inactive, data, next);
                /* FALLTHROUGH */
        case USB_ST_SETUP:
@@ -1898,6 +1927,11 @@ tr_setup:
                 */
                RSU_UNLOCK(sc);
                while (m != NULL) {
+                       int rssi;
+
+                       /* Cheat and get the last calibrated RSSI */
+                       rssi = rsu_hwrssi_to_rssi(sc, sc->sc_currssi);
+
                        next = m->m_next;
                        m->m_next = NULL;
                        wh = mtod(m, struct ieee80211_frame *);
@@ -1906,10 +1940,10 @@ tr_setup:
                        if (ni != NULL) {
                                if (ni->ni_flags & IEEE80211_NODE_HT)
                                        m->m_flags |= M_AMPDU;
-                               (void)ieee80211_input(ni, m, rssi, 0);
+                               (void)ieee80211_input(ni, m, rssi, -96);
                                ieee80211_free_node(ni);
                        } else
-                               (void)ieee80211_input_all(ic, m, rssi, 0);
+                               (void)ieee80211_input_all(ic, m, rssi, -96);
                        m = next;
                }
                RSU_LOCK(sc);
@@ -2003,6 +2037,12 @@ tr_setup:
                }
                break;
        }
+
+       /*
+        * XXX TODO: if the queue is low, flush out FF TX frames.
+        * Remember to unlock the driver for now; net80211 doesn't
+        * defer it for us.
+        */
 }
 
 static void

diff --git a/sys/dev/usb/wlan/if_rsureg.h b/sys/dev/usb/wlan/if_rsureg.h
index 28801972286aa0d2526e9c484708c36bde16a4fc..ddb29a36770ef4a1a96b185be8ada8076a977ff9 100644 (file)
--- a/sys/dev/usb/wlan/if_rsureg.h
+++ b/sys/dev/usb/wlan/if_rsureg.h
@@ -764,6 +764,7 @@ struct rsu_softc {
        int                             sc_ht;
        int                             sc_nendpoints;
        int                             sc_curpwrstate;
+       int                             sc_currssi;
 
        u_int                           sc_running:1,
                                        sc_calibrating:1,