ath10k: add support for configuring management packet rate

By default the firmware uses 1Mbps and 6Mbps rate for management packets
in 2G and 5G bands respectively. But when the user selects different
basic rates from the userspace, we need to send the management
packets at the lowest basic rate selected by the user.

This change makes use of WMI_VDEV_PARAM_MGMT_RATE param for configuring the
management packets rate to the firmware.

Chipsets Tested : QCA988X, QCA9887, QCA9984
FW Tested 	: 10.2.4-1.0-41, 10.4-3.6.104
Signed-off-by: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath10k/mac.c

@@ -157,6 +157,22 @@ u8 ath10k_mac_bitrate_to_idx(const struct ieee80211_supported_band *sband,
 	return 0;
 }
 
+static int ath10k_mac_get_rate_hw_value(int bitrate)
+{
+	int i;
+	u8 hw_value_prefix = 0;
+
+	if (ath10k_mac_bitrate_is_cck(bitrate))
+		hw_value_prefix = WMI_RATE_PREAMBLE_CCK << 6;
+
+	for (i = 0; i < sizeof(ath10k_rates); i++) {
+		if (ath10k_rates[i].bitrate == bitrate)
+			return hw_value_prefix | ath10k_rates[i].hw_value;
+	}
+
+	return -EINVAL;
+}
+
 static int ath10k_mac_get_max_vht_mcs_map(u16 mcs_map, int nss)
 {
 	switch ((mcs_map >> (2 * nss)) & 0x3) {
@@ -5452,9 +5468,10 @@ static void ath10k_bss_info_changed(struct ieee80211_hw *hw,
 	struct cfg80211_chan_def def;
 	u32 vdev_param, pdev_param, slottime, preamble;
 	u16 bitrate, hw_value;
-	u8 rate;
-	int rateidx, ret = 0;
+	u8 rate, basic_rate_idx;
+	int rateidx, ret = 0, hw_rate_code;
 	enum nl80211_band band;
+	const struct ieee80211_supported_band *sband;
 
 	mutex_lock(&ar->conf_mutex);
 
@@ -5660,6 +5677,30 @@ static void ath10k_bss_info_changed(struct ieee80211_hw *hw,
 				    arvif->vdev_id,  ret);
 	}
 
+	if (changed & BSS_CHANGED_BASIC_RATES) {
+		if (WARN_ON(ath10k_mac_vif_chan(vif, &def))) {
+			mutex_unlock(&ar->conf_mutex);
+			return;
+		}
+
+	sband = ar->hw->wiphy->bands[def.chan->band];
+	basic_rate_idx = ffs(vif->bss_conf.basic_rates) - 1;
+	bitrate = sband->bitrates[basic_rate_idx].bitrate;
+
+	hw_rate_code = ath10k_mac_get_rate_hw_value(bitrate);
+	if (hw_rate_code < 0) {
+		ath10k_warn(ar, "bitrate not supported %d\n", bitrate);
+		mutex_unlock(&ar->conf_mutex);
+		return;
+	}
+
+	vdev_param = ar->wmi.vdev_param->mgmt_rate;
+	ret = ath10k_wmi_vdev_set_param(ar, arvif->vdev_id, vdev_param,
+					hw_rate_code);
+	if (ret)
+		ath10k_warn(ar, "failed to set mgmt tx rate %d\n", ret);
+	}
+
 	mutex_unlock(&ar->conf_mutex);
 }