Add initial support for MIMO statistics to net80211.

This introduces struct ieee80211_rx_stats - which stores the various kinds
of RX statistics which a MIMO and non-MIMO 802.11 device can export.

It also fleshes out the mimo export to userland (node_getmimoinfo()).

It assumes that MIMO radios (for now) export both ctl and ext channels.
Non-11n MIMO radios are possible (and I believe Atheros made at least
one), so if that chipset support is added, extra flags to the
struct ieee80211_rx_stats can be added to extend this support.

Two new input functions have been added - ieee80211_input_mimo() and
ieee80211_input_mimo_all() - which MIMO-aware devices can call with
MIMO specific statistics.

802.11 devices calling the non-MIMO input functions will still function.

1 files changed, 46 insertions, 1 deletions

diff --git a/sys/net80211/ieee80211_input.c b/sys/net80211/ieee80211_input.c
index c372370..a18da4a 100644
--- a/sys/net80211/ieee80211_input.c
+++ b/sys/net80211/ieee80211_input.c
@@ -57,9 +57,54 @@ __FBSDID("$FreeBSD$");
 #include <net/ethernet.h>
 #endif
 
+static void
+ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
+{
+	int i;
+
+	/* Verify the required MIMO bits are set */
+	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
+	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
+		return;
+
+	/* XXX This assumes the MIMO radios have both ctl and ext chains */
+	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
+		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
+		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
+	}
+
+	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
+	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
+		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
+		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
+	}
+	ni->ni_mimo_chains = rx->c_chain;
+}
+
+int
+ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
+    struct ieee80211_rx_stats *rx)
+{
+	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
+	ieee80211_process_mimo(ni, rx);
+	return ieee80211_input(ni, m, rx->rssi, rx->nf);
+}
+
 int
 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
 {
+	struct ieee80211_rx_stats rx;
+
+	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
+	rx.nf = nf;
+	rx.rssi = rssi;
+	return ieee80211_input_mimo_all(ic, m, &rx);
+}
+
+int
+ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
+    struct ieee80211_rx_stats *rx)
+{
 	struct ieee80211vap *vap;
 	int type = -1;
 
@@ -96,7 +141,7 @@ ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
 			m = NULL;
 		}
 		ni = ieee80211_ref_node(vap->iv_bss);
-		type = ieee80211_input(ni, mcopy, rssi, nf);
+		type = ieee80211_input_mimo(ni, mcopy, rx);
 		ieee80211_free_node(ni);
 	}
 	if (m != NULL)			/* no vaps, reclaim mbuf */