wifi: iwlwifi: mvm: refactor TX rate handling

Refactor the injection and other frame TX rate handling
to always return the injection rate directly, by factoring
the legay rate portion out into a new function called in
the two relevant places (injection and non-injection).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230921110727.dc920357bad0.I5ee8512fb63f0423c1da35b59fea8811d60c1ad3@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/tx.c

@@ -262,6 +262,38 @@ static u32 iwl_mvm_get_tx_ant(struct iwl_mvm *mvm,
 	return BIT(mvm->mgmt_last_antenna_idx) << RATE_MCS_ANT_POS;
 }
 
+static u32 iwl_mvm_convert_rate_idx(struct iwl_mvm *mvm,
+				    struct ieee80211_tx_info *info,
+				    int rate_idx)
+{
+	u32 rate_flags = 0;
+	u8 rate_plcp;
+	bool is_cck;
+
+	/* if the rate isn't a well known legacy rate, take the lowest one */
+	if (rate_idx < 0 || rate_idx >= IWL_RATE_COUNT_LEGACY)
+		rate_idx = iwl_mvm_mac_ctxt_get_lowest_rate(mvm,
+							    info,
+							    info->control.vif);
+
+	/* Get PLCP rate for tx_cmd->rate_n_flags */
+	rate_plcp = iwl_mvm_mac80211_idx_to_hwrate(mvm->fw, rate_idx);
+	is_cck = (rate_idx >= IWL_FIRST_CCK_RATE) &&
+		 (rate_idx <= IWL_LAST_CCK_RATE);
+
+	/* Set CCK or OFDM flag */
+	if (iwl_fw_lookup_cmd_ver(mvm->fw, TX_CMD, 0) > 8) {
+		if (!is_cck)
+			rate_flags |= RATE_MCS_LEGACY_OFDM_MSK;
+		else
+			rate_flags |= RATE_MCS_CCK_MSK;
+	} else if (is_cck) {
+		rate_flags |= RATE_MCS_CCK_MSK_V1;
+	}
+
+	return (u32)rate_plcp | rate_flags;
+}
+
 static u32 iwl_mvm_get_inject_tx_rate(struct iwl_mvm *mvm,
 				      struct ieee80211_tx_info *info)
 {
@@ -288,6 +320,9 @@ static u32 iwl_mvm_get_inject_tx_rate(struct iwl_mvm *mvm,
 			result |= u32_encode_bits(2, RATE_MCS_CHAN_WIDTH_MSK_V1);
 		else if (rate->flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 			result |= u32_encode_bits(3, RATE_MCS_CHAN_WIDTH_MSK_V1);
+
+		if (iwl_fw_lookup_notif_ver(mvm->fw, LONG_GROUP, TX_CMD, 0) > 6)
+			result = iwl_new_rate_from_v1(result);
 	} else if (rate->flags & IEEE80211_TX_RC_MCS) {
 		result = RATE_MCS_HT_MSK_V1;
 		result |= u32_encode_bits(rate->idx,
@@ -301,12 +336,15 @@ static u32 iwl_mvm_get_inject_tx_rate(struct iwl_mvm *mvm,
 			result |= RATE_MCS_LDPC_MSK_V1;
 		if (u32_get_bits(info->flags, IEEE80211_TX_CTL_STBC))
 			result |= RATE_MCS_STBC_MSK;
+
+		if (iwl_fw_lookup_notif_ver(mvm->fw, LONG_GROUP, TX_CMD, 0) > 6)
+			result = iwl_new_rate_from_v1(result);
 	} else {
-		return 0;
+		int rate_idx = info->control.rates[0].idx;
+
+		result = iwl_mvm_convert_rate_idx(mvm, info, rate_idx);
 	}
 
-	if (iwl_fw_lookup_notif_ver(mvm->fw, LONG_GROUP, TX_CMD, 0) > 6)
-		return iwl_new_rate_from_v1(result);
 	return result;
 }
 
@@ -315,17 +353,11 @@ static u32 iwl_mvm_get_tx_rate(struct iwl_mvm *mvm,
 			       struct ieee80211_sta *sta, __le16 fc)
 {
 	int rate_idx = -1;
-	u8 rate_plcp;
-	u32 rate_flags = 0;
-	bool is_cck;
 
-	if (unlikely(info->control.flags & IEEE80211_TX_CTRL_RATE_INJECT)) {
-		u32 result = iwl_mvm_get_inject_tx_rate(mvm, info);
+	if (unlikely(info->control.flags & IEEE80211_TX_CTRL_RATE_INJECT))
+		return iwl_mvm_get_inject_tx_rate(mvm, info);
 
-		if (result)
-			return result;
-		rate_idx = info->control.rates[0].idx;
-	} else if (!ieee80211_hw_check(mvm->hw, HAS_RATE_CONTROL)) {
+	if (!ieee80211_hw_check(mvm->hw, HAS_RATE_CONTROL)) {
 		/* info->control is only relevant for non HW rate control */
 
 		/* HT rate doesn't make sense for a non data frame */
@@ -350,27 +382,7 @@ static u32 iwl_mvm_get_tx_rate(struct iwl_mvm *mvm,
 		BUILD_BUG_ON(IWL_FIRST_CCK_RATE != 0);
 	}
 
-	/* if the rate isn't a well known legacy rate, take the lowest one */
-	if (rate_idx < 0 || rate_idx >= IWL_RATE_COUNT_LEGACY)
-		rate_idx = iwl_mvm_mac_ctxt_get_lowest_rate(mvm,
-							    info,
-							    info->control.vif);
-
-	/* Get PLCP rate for tx_cmd->rate_n_flags */
-	rate_plcp = iwl_mvm_mac80211_idx_to_hwrate(mvm->fw, rate_idx);
-	is_cck = (rate_idx >= IWL_FIRST_CCK_RATE) && (rate_idx <= IWL_LAST_CCK_RATE);
-
-	/* Set CCK or OFDM flag */
-	if (iwl_fw_lookup_cmd_ver(mvm->fw, TX_CMD, 0) > 8) {
-		if (!is_cck)
-			rate_flags |= RATE_MCS_LEGACY_OFDM_MSK;
-		else
-			rate_flags |= RATE_MCS_CCK_MSK;
-	} else if (is_cck) {
-		rate_flags |= RATE_MCS_CCK_MSK_V1;
-	}
-
-	return (u32)rate_plcp | rate_flags;
+	return iwl_mvm_convert_rate_idx(mvm, info, rate_idx);
 }
 
 static u32 iwl_mvm_get_tx_rate_n_flags(struct iwl_mvm *mvm,