nl80211: Add support for EDMG channels

802.11ay specification defines Enhanced Directional Multi-Gigabit
(EDMG) STA and AP which allow channel bonding of 2 channels and more.

Introduce new NL attributes that are needed for enabling and
configuring EDMG support.

Two new attributes are used by kernel to publish driver's EDMG
capabilities to the userspace:
NL80211_BAND_ATTR_EDMG_CHANNELS - bitmap field that indicates the 2.16
GHz channel(s) that are supported by the driver.
When this attribute is not set it means driver does not support EDMG.
NL80211_BAND_ATTR_EDMG_BW_CONFIG - represent the channel bandwidth
configurations supported by the driver.

Additional two new attributes are used by the userspace for connect
command and for AP configuration:
NL80211_ATTR_WIPHY_EDMG_CHANNELS
NL80211_ATTR_WIPHY_EDMG_BW_CONFIG

New rate info flag - RATE_INFO_FLAGS_EDMG, can be reported from driver
and used for bitrate calculation that will take into account EDMG
according to the 802.11ay specification.

Signed-off-by: Alexei Avshalom Lazar <ailizaro@codeaurora.org>
Link: https://lore.kernel.org/r/1566138918-3823-2-git-send-email-ailizaro@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 159 insertions, 0 deletions

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 7c9d204838d4..e851cafd8e2f 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -14,6 +14,11 @@
 #include "core.h"
 #include "rdev-ops.h"
 
+static bool cfg80211_valid_60g_freq(u32 freq)
+{
+	return freq >= 58320 && freq <= 70200;
+}
+
 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
 			     struct ieee80211_channel *chan,
 			     enum nl80211_channel_type chan_type)
@@ -23,6 +28,8 @@ void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
 
 	chandef->chan = chan;
 	chandef->center_freq2 = 0;
+	chandef->edmg.bw_config = 0;
+	chandef->edmg.channels = 0;
 
 	switch (chan_type) {
 	case NL80211_CHAN_NO_HT:
@@ -47,6 +54,91 @@ void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
 }
 EXPORT_SYMBOL(cfg80211_chandef_create);
 
+static bool cfg80211_edmg_chandef_valid(const struct cfg80211_chan_def *chandef)
+{
+	int max_contiguous = 0;
+	int num_of_enabled = 0;
+	int contiguous = 0;
+	int i;
+
+	if (!chandef->edmg.channels || !chandef->edmg.bw_config)
+		return false;
+
+	if (!cfg80211_valid_60g_freq(chandef->chan->center_freq))
+		return false;
+
+	for (i = 0; i < 6; i++) {
+		if (chandef->edmg.channels & BIT(i)) {
+			contiguous++;
+			num_of_enabled++;
+		} else {
+			contiguous = 0;
+		}
+
+		max_contiguous = max(contiguous, max_contiguous);
+	}
+	/* basic verification of edmg configuration according to
+	 * IEEE P802.11ay/D4.0 section 9.4.2.251
+	 */
+	/* check bw_config against contiguous edmg channels */
+	switch (chandef->edmg.bw_config) {
+	case IEEE80211_EDMG_BW_CONFIG_4:
+	case IEEE80211_EDMG_BW_CONFIG_8:
+	case IEEE80211_EDMG_BW_CONFIG_12:
+		if (max_contiguous < 1)
+			return false;
+		break;
+	case IEEE80211_EDMG_BW_CONFIG_5:
+	case IEEE80211_EDMG_BW_CONFIG_9:
+	case IEEE80211_EDMG_BW_CONFIG_13:
+		if (max_contiguous < 2)
+			return false;
+		break;
+	case IEEE80211_EDMG_BW_CONFIG_6:
+	case IEEE80211_EDMG_BW_CONFIG_10:
+	case IEEE80211_EDMG_BW_CONFIG_14:
+		if (max_contiguous < 3)
+			return false;
+		break;
+	case IEEE80211_EDMG_BW_CONFIG_7:
+	case IEEE80211_EDMG_BW_CONFIG_11:
+	case IEEE80211_EDMG_BW_CONFIG_15:
+		if (max_contiguous < 4)
+			return false;
+		break;
+
+	default:
+		return false;
+	}
+
+	/* check bw_config against aggregated (non contiguous) edmg channels */
+	switch (chandef->edmg.bw_config) {
+	case IEEE80211_EDMG_BW_CONFIG_4:
+	case IEEE80211_EDMG_BW_CONFIG_5:
+	case IEEE80211_EDMG_BW_CONFIG_6:
+	case IEEE80211_EDMG_BW_CONFIG_7:
+		break;
+	case IEEE80211_EDMG_BW_CONFIG_8:
+	case IEEE80211_EDMG_BW_CONFIG_9:
+	case IEEE80211_EDMG_BW_CONFIG_10:
+	case IEEE80211_EDMG_BW_CONFIG_11:
+		if (num_of_enabled < 2)
+			return false;
+		break;
+	case IEEE80211_EDMG_BW_CONFIG_12:
+	case IEEE80211_EDMG_BW_CONFIG_13:
+	case IEEE80211_EDMG_BW_CONFIG_14:
+	case IEEE80211_EDMG_BW_CONFIG_15:
+		if (num_of_enabled < 4 || max_contiguous < 2)
+			return false;
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
 {
 	u32 control_freq;
@@ -112,6 +204,10 @@ bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
 		return false;
 	}
 
+	if (cfg80211_chandef_is_edmg(chandef) &&
+	    !cfg80211_edmg_chandef_valid(chandef))
+		return false;
+
 	return true;
 }
 EXPORT_SYMBOL(cfg80211_chandef_valid);
@@ -721,12 +817,66 @@ static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 	return true;
 }
 
+/* check if the operating channels are valid and supported */
+static bool cfg80211_edmg_usable(struct wiphy *wiphy, u8 edmg_channels,
+				 enum ieee80211_edmg_bw_config edmg_bw_config,
+				 int primary_channel,
+				 struct ieee80211_edmg *edmg_cap)
+{
+	struct ieee80211_channel *chan;
+	int i, freq;
+	int channels_counter = 0;
+
+	if (!edmg_channels && !edmg_bw_config)
+		return true;
+
+	if ((!edmg_channels && edmg_bw_config) ||
+	    (edmg_channels && !edmg_bw_config))
+		return false;
+
+	if (!(edmg_channels & BIT(primary_channel - 1)))
+		return false;
+
+	/* 60GHz channels 1..6 */
+	for (i = 0; i < 6; i++) {
+		if (!(edmg_channels & BIT(i)))
+			continue;
+
+		if (!(edmg_cap->channels & BIT(i)))
+			return false;
+
+		channels_counter++;
+
+		freq = ieee80211_channel_to_frequency(i + 1,
+						      NL80211_BAND_60GHZ);
+		chan = ieee80211_get_channel(wiphy, freq);
+		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
+			return false;
+	}
+
+	/* IEEE802.11 allows max 4 channels */
+	if (channels_counter > 4)
+		return false;
+
+	/* check bw_config is a subset of what driver supports
+	 * (see IEEE P802.11ay/D4.0 section 9.4.2.251, Table 13)
+	 */
+	if ((edmg_bw_config % 4) > (edmg_cap->bw_config % 4))
+		return false;
+
+	if (edmg_bw_config > edmg_cap->bw_config)
+		return false;
+
+	return true;
+}
+
 bool cfg80211_chandef_usable(struct wiphy *wiphy,
 			     const struct cfg80211_chan_def *chandef,
 			     u32 prohibited_flags)
 {
 	struct ieee80211_sta_ht_cap *ht_cap;
 	struct ieee80211_sta_vht_cap *vht_cap;
+	struct ieee80211_edmg *edmg_cap;
 	u32 width, control_freq, cap;
 
 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
@@ -734,6 +884,15 @@ bool cfg80211_chandef_usable(struct wiphy *wiphy,
 
 	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
 	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
+	edmg_cap = &wiphy->bands[chandef->chan->band]->edmg_cap;
+
+	if (edmg_cap->channels &&
+	    !cfg80211_edmg_usable(wiphy,
+				  chandef->edmg.channels,
+				  chandef->edmg.bw_config,
+				  chandef->chan->hw_value,
+				  edmg_cap))
+		return false;
 
 	control_freq = chandef->chan->center_freq;