PERFORCE change 115110 for review

[Sepherosa Ziehau]

http://perforce.freebsd.org/chv.cgi?CH=115110

Change 115110 by sephe at sephe_zealot:sam_wifi on 2007/02/27 10:41:29

	Convert RSSI to receive signal strength for rt2661 part.
	
	Reviewed by:	sam@
	Approved by:	sam@

Affected files ...

.. //depot/projects/wifi/sys/dev/ral/rt2661.c#8 edit
.. //depot/projects/wifi/sys/dev/ral/rt2661reg.h#2 edit

Differences ...

==== //depot/projects/wifi/sys/dev/ral/rt2661.c#8 (text) ====

@@ -1008,6 +1008,8 @@
 	    BUS_DMASYNC_POSTREAD);
 
 	for (;;) {
+		int rssi;
+
 		desc = &sc->rxq.desc[sc->rxq.cur];
 		data = &sc->rxq.data[sc->rxq.cur];
 
@@ -1080,6 +1082,8 @@
 		m->m_pkthdr.len = m->m_len =
 		    (le32toh(desc->flags) >> 16) & 0xfff;
 
+		rssi = rt2661_get_rssi(sc, desc->rssi);
+
 		if (bpf_peers_present(sc->sc_drvbpf)) {
 			struct rt2661_rx_radiotap_header *tap = &sc->sc_rxtap;
 			uint32_t tsf_lo, tsf_hi;
@@ -1094,7 +1098,7 @@
 			tap->wr_rate = rt2661_rxrate(desc);
 			tap->wr_chan_freq = htole16(ic->ic_curchan->ic_freq);
 			tap->wr_chan_flags = htole16(ic->ic_curchan->ic_flags);
-			tap->wr_antsignal = desc->rssi;
+			tap->wr_antsignal = rssi < 0 ? 0 : rssi;
 
 			bpf_mtap2(sc->sc_drvbpf, tap, sc->sc_rxtap_len, m);
 		}
@@ -1104,15 +1108,18 @@
 		ni = ieee80211_find_rxnode(ic,
 		    (struct ieee80211_frame_min *)wh);
 
+		/* Error happened during RSSI conversion. */
+		if (rssi < 0)
+			rssi = ni->ni_rssi;
+
 		/* send the frame to the 802.11 layer */
-		ieee80211_input(ic, m, ni, desc->rssi, 0, 0);
+		ieee80211_input(ic, m, ni, rssi, RT2661_NOISE_FLOOR, 0);
 
 		/* give rssi to the rate adatation algorithm */
 		rn = (struct rt2661_node *)ni;
 		RAL_LOCK(sc);
 		sc->sc_flags &= ~RAL_INPUT_RUNNING;
-		ral_rssadapt_input(ic, ni, &rn->rssadapt,
-		    rt2661_get_rssi(sc, desc->rssi));
+		ral_rssadapt_input(ic, ni, &rn->rssadapt, rssi);
 
 		/* node is no longer needed */
 		ieee80211_free_node(ni);
@@ -2334,10 +2341,18 @@
 	if ((val & 0xff) != 0xff)
 		sc->rssi_2ghz_corr = (int8_t)(val & 0xff);	/* signed */
 
+	/* Only [-10, 10] is valid */
+	if (sc->rssi_2ghz_corr < -10 || sc->rssi_2ghz_corr > 10)
+		sc->rssi_2ghz_corr = 0;
+
 	val = rt2661_eeprom_read(sc, RT2661_EEPROM_RSSI_5GHZ_OFFSET);
 	if ((val & 0xff) != 0xff)
 		sc->rssi_5ghz_corr = (int8_t)(val & 0xff);	/* signed */
 
+	/* Only [-10, 10] is valid */
+	if (sc->rssi_5ghz_corr < -10 || sc->rssi_5ghz_corr > 10)
+		sc->rssi_5ghz_corr = 0;
+
 	/* adjust RSSI correction for external low-noise amplifier */
 	if (sc->ext_2ghz_lna)
 		sc->rssi_2ghz_corr -= 14;
@@ -2836,7 +2851,17 @@
 	lna = (raw >> 5) & 0x3;
 	agc = raw & 0x1f;
 
-	rssi = 2 * agc;
+	if (lna == 0) {
+		/*
+		 * No mapping available.
+		 *
+		 * NB: Since RSSI is relative to noise floor, -1 is
+		 *     adequate for caller to know error happened.
+		 */
+		return -1;
+	}
+
+	rssi = (2 * agc) - RT2661_NOISE_FLOOR;
 
 	if (IEEE80211_IS_CHAN_2GHZ(sc->sc_curchan)) {
 		rssi += sc->rssi_2ghz_corr;

==== //depot/projects/wifi/sys/dev/ral/rt2661reg.h#2 (text) ====

@@ -17,6 +17,8 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#define RT2661_NOISE_FLOOR	-95
+
 #define RT2661_TX_RING_COUNT	32
 #define RT2661_MGT_RING_COUNT	32
 #define RT2661_RX_RING_COUNT	64