qcacld-3.0: Give preference to 5 GHz low freq in ACS

For LL_LT_SAP, give preference to 5 GHz low frequency to select
channel during ACS.

In case of SBS, it's better to bring up LL_LT_SAP on 5 GHz low
as there will be less number of passive channels on 5 GHz low
band compared to 5 GHz high band.

Change-Id: I1d7f7c08c315394315df3b360c9c632d17a4b39a
CRs-Fixed: 3648218

components/cmn_services/policy_mgr/inc/wlan_policy_mgr_api.h

@@ -5712,4 +5712,15 @@ QDF_STATUS policy_mgr_get_pcl_ch_list_for_ll_sap(
 					struct connection_info *info,
 					uint8_t *connection_count);
 #endif
+
+/**
+ * policy_mgr_is_given_freq_5g_low() - API to check whether given freq
+ * is 5GHz low or not
+ * @psoc: psoc object
+ * @given_freq: given freq
+ *
+ * Return: True if it 5GHz low otherwise false
+ */
+bool policy_mgr_is_given_freq_5g_low(struct wlan_objmgr_psoc *psoc,
+				     qdf_freq_t given_freq);
 #endif /* __WLAN_POLICY_MGR_API_H */

components/cmn_services/policy_mgr/src/wlan_policy_mgr_get_set_utils.c

@@ -12684,3 +12684,18 @@ policy_mgr_get_connection_max_channel_width(struct wlan_objmgr_psoc *psoc)
 	return bw;
 }
 
+bool policy_mgr_is_given_freq_5g_low(struct wlan_objmgr_psoc *psoc,
+				     qdf_freq_t given_freq)
+{
+	qdf_freq_t sbs_cut_off_freq;
+
+	sbs_cut_off_freq = policy_mgr_get_sbs_cut_off_freq(psoc);
+	if (!sbs_cut_off_freq)
+		return false;
+
+	if (given_freq < sbs_cut_off_freq &&
+	    WLAN_REG_IS_5GHZ_CH_FREQ(given_freq))
+		return true;
+
+	return false;
+}

core/sap/src/sap_ch_select.c

@@ -1472,6 +1472,59 @@ static void sap_update_6ghz_max_weight(struct sap_sel_ch_info *ch_info_params,
 	}
 }
 
+/**
+ * sap_update_5ghz_low_freq_weight() - Update weight of 5GHz low frequency
+ * @psoc: Pointer to psoc
+ * @ch_info_params: Pointer to sap_sel_ch_info structure
+ *
+ * This api helps to lower the 5GHz low frequency weight by
+ * SAP_NORMALISE_ACS_WEIGHT so that it will get more preference to get
+ * selected during ACS.
+ *
+ * Return: void
+ */
+static void sap_update_5ghz_low_freq_weight(
+					struct wlan_objmgr_psoc *psoc,
+					struct sap_sel_ch_info *ch_info_params)
+{
+	uint8_t ch_num;
+	qdf_freq_t freq;
+	uint32_t weight;
+
+	if (!policy_mgr_is_hw_sbs_capable(psoc))
+		return;
+
+	for (ch_num = 0; ch_num < ch_info_params->num_ch; ch_num++) {
+		freq = ch_info_params->ch_info[ch_num].chan_freq;
+		weight = ch_info_params->ch_info[ch_num].weight;
+		if (policy_mgr_is_given_freq_5g_low(psoc, freq)) {
+			/*
+			 * Lower the weight by SAP_NORMALISE_ACS_WEIGHT i.e 5%
+			 * from channel weight itself. Later if required, modify
+			 * this value.
+			 * Here are the few observation captured which results
+			 * to go with SAP_NORMALISE_ACS_WEIGHT.
+			 *
+			 * +-----------+-------------+------------+---------------+--------------------------------------+
+			 * |   freq    |  bss_count  |    rssi    |     weight    |              observation             |
+			 * +---------------------------------------------------------------------------------------------+
+			 * |  5G low   |    >6       | -76 - -56  | 17419 - 17774 | Diff b/w 5G low & 5G high min weight |
+			 * |  5G high  |    <4       | -100 - -50 | 16842 - 17685 | is ~5% of 5G low min weight		 |
+			 * |	       |	     |		  |		  |					 |
+			 * |  5G low   |    >6       | -77 - -54  | 17419 - 17730 | Diff b/w 5G low & 5G high min weight |
+			 * |  5G high  |    <4	     | -100 - -50 | 16842 - 17552 | is ~5% of 5G low min weight		 |
+			 * |	       |	     |		  |		  |					 |
+			 * |  5G low   |    >5       | -77 - -57  | 17286 - 17552 | Diff b/w 5G low & 5G high min weight |
+			 * |  5G high  |    <4       | -100 - -50 | 16842 - 17596 | is ~5% of 5G low min weight		 |
+			 * +-----------+-------------+------------+---------------+--------------------------------------+
+			 */
+
+			weight = weight - ((weight * SAP_NORMALISE_ACS_WEIGHT ) / 100);
+			ch_info_params->ch_info[ch_num].weight = weight;
+		}
+	}
+}
+
 /**
  * sap_compute_spect_weight() - Compute spectrum weight
  * @ch_info_params: Pointer to the tSpectInfoParams structure
@@ -1652,6 +1705,10 @@ debug_info:
 	}
 	sap_update_6ghz_max_weight(ch_info_params,
 				   max_valid_weight_6ghz);
+
+	if (policy_mgr_is_vdev_ll_lt_sap(mac->psoc, sap_ctx->vdev_id))
+		sap_update_5ghz_low_freq_weight(mac->psoc, ch_info_params);
+
 	sap_clear_channel_status(mac);
 }
 

core/sap/src/sap_ch_select.h

@@ -58,6 +58,8 @@
 #define REG_MAX_EIRP_POWER 36
 #define REG_MIN_EIRP_POWER 14
 
+#define SAP_NORMALISE_ACS_WEIGHT 5
+
 /* In HT40/VHT80, Effect of primary Channel RSSi on Subband1 */
 #define SAP_SUBBAND1_RSSI_EFFECT_PRIMARY  (-20)
 /* In VHT80, Effect of primary Channel RSSI on Subband2 */