mt76: mt7915: fix rate setting of tx descriptor in testmode

Fix ofdm rate index and ldpc setting in rate setting field of tx
descriptor.
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7915/mac.c

@@ -661,19 +661,18 @@ mt7915_mac_write_txwi_tm(struct mt7915_phy *phy, __le32 *txwi,
 {
 #ifdef CONFIG_NL80211_TESTMODE
 	struct mt76_testmode_data *td = &phy->mt76->test;
+	const struct ieee80211_rate *r;
+	u8 bw, mode, nss = td->tx_rate_nss;
 	u8 rate_idx = td->tx_rate_idx;
-	u8 nss = td->tx_rate_nss;
-	u8 bw, mode;
 	u16 rateval = 0;
 	u32 val;
+	bool cck = false;
+	int band;
 
 	if (skb != phy->mt76->test.tx_skb)
 		return;
 
 	switch (td->tx_rate_mode) {
-	case MT76_TM_TX_MODE_CCK:
-		mode = MT_PHY_TYPE_CCK;
-		break;
 	case MT76_TM_TX_MODE_HT:
 		nss = 1 + (rate_idx >> 3);
 		mode = MT_PHY_TYPE_HT;
@@ -693,7 +692,20 @@ mt7915_mac_write_txwi_tm(struct mt7915_phy *phy, __le32 *txwi,
 	case MT76_TM_TX_MODE_HE_MU:
 		mode = MT_PHY_TYPE_HE_MU;
 		break;
+	case MT76_TM_TX_MODE_CCK:
+		cck = true;
+		fallthrough;
 	case MT76_TM_TX_MODE_OFDM:
+		band = phy->mt76->chandef.chan->band;
+		if (band == NL80211_BAND_2GHZ && !cck)
+			rate_idx += 4;
+
+		r = &phy->mt76->hw->wiphy->bands[band]->bitrates[rate_idx];
+		val = cck ? r->hw_value_short : r->hw_value;
+
+		mode = val >> 8;
+		rate_idx = val & 0xff;
+		break;
 	default:
 		mode = MT_PHY_TYPE_OFDM;
 		break;
@@ -748,9 +760,10 @@ mt7915_mac_write_txwi_tm(struct mt7915_phy *phy, __le32 *txwi,
 	if (mode >= MT_PHY_TYPE_HE_SU)
 		val |= FIELD_PREP(MT_TXD6_HELTF, td->tx_ltf);
 
-	if (td->tx_rate_ldpc || bw > 0)
+	if (td->tx_rate_ldpc || (bw > 0 && mode >= MT_PHY_TYPE_HE_SU))
 		val |= MT_TXD6_LDPC;
 
+	txwi[3] &= ~cpu_to_le32(MT_TXD3_SN_VALID);
 	txwi[6] |= cpu_to_le32(val);
 	txwi[7] |= cpu_to_le32(FIELD_PREP(MT_TXD7_SPE_IDX,
 					  phy->test.spe_idx));