From:   greearb@candelatech.com
To:     linux-wireless@vger.kernel.org
Cc:     Ben Greear <greearb@candelatech.com>
Subject: [PATCH 3/8] mt76: mt7915: debugfs hook to enable TXS for NO_SKB pkt-ids
Date:   Thu, 18 Nov 2021 08:45:44 -0800
Message-Id: <20211118164549.3863-3-greearb@candelatech.com>
In-Reply-To: <20211118164549.3863-1-greearb@candelatech.com>
References: <20211118164549.3863-1-greearb@candelatech.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Ben Greear <greearb@candelatech.com>

This lets user turn on/off this feature.  Enabling gives better
tx-rate related stats, but will cause extra driver and (maybe)
firmware work.  Not sure if it actually affects performance or
not.

Signed-off-by: Ben Greear <greearb@candelatech.com>
---
 .../wireless/mediatek/mt76/mt7915/debugfs.c   | 24 +++++++++++++++++++
 .../net/wireless/mediatek/mt76/mt7915/mac.c   |  3 ++-
 .../wireless/mediatek/mt76/mt7915/mt7915.h    |  5 ++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c b/drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c
index a15aa256d0cf..c5ed02cd2afc 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c
@@ -190,6 +190,29 @@ mt7915_fw_util_wa_show(struct seq_file *file, void *data)
 
 DEFINE_SHOW_ATTRIBUTE(mt7915_fw_util_wa);
 
+static int
+mt7915_txs_for_no_skb_set(void *data, u64 val)
+{
+	struct mt7915_dev *dev = data;
+
+	dev->txs_for_no_skb_enabled = !!val;
+
+	return 0;
+}
+
+static int
+mt7915_txs_for_no_skb_get(void *data, u64 *val)
+{
+	struct mt7915_dev *dev = data;
+
+	*val = dev->txs_for_no_skb_enabled;
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(fops_txs_for_no_skb, mt7915_txs_for_no_skb_get,
+			 mt7915_txs_for_no_skb_set, "%lld\n");
+
 static void
 mt7915_ampdu_stat_read_phy(struct mt7915_phy *phy,
 			   struct seq_file *file)
@@ -540,6 +563,7 @@ int mt7915_init_debugfs(struct mt7915_phy *phy)
 			    &mt7915_fw_util_wm_fops);
 	debugfs_create_file("fw_util_wa", 0400, dir, dev,
 			    &mt7915_fw_util_wa_fops);
+	debugfs_create_file("force_txs", 0600, dir, dev, &fops_txs_for_no_skb);
 	debugfs_create_file("implicit_txbf", 0600, dir, dev,
 			    &fops_implicit_txbf);
 	debugfs_create_file("txpower_sku", 0400, dir, phy,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
index adc6d4ddbccf..e37e6b05c7a4 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
@@ -1096,7 +1096,8 @@ void mt7915_mac_write_txwi(struct mt7915_dev *dev, __le32 *txwi,
 	txwi[4] = 0;
 
 	val = FIELD_PREP(MT_TXD5_PID, pid);
-	if (pid >= MT_PACKET_ID_FIRST)
+	if (pid >= MT_PACKET_ID_FIRST ||
+	    (pid == MT_PACKET_ID_NO_SKB && dev->txs_for_no_skb_enabled))
 		val |= MT_TXD5_TX_STATUS_HOST;
 	txwi[5] = cpu_to_le32(val);
 
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h b/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h
index e69b4c8974ee..8b1d4664562a 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h
@@ -254,6 +254,11 @@ struct mt7915_dev {
 
 	u16 chainmask;
 	u32 hif_idx;
+	/* Should we request TXS for MT_PACKET_ID_NO_SKB?  Doing so gives better
+	 * costs but causes a great deal more TXS packet processing by driver and
+	 * creation by firmware, so may be a performance drag.
+	 */
+	bool txs_for_no_skb_enabled;
 
 	struct work_struct init_work;
 	struct work_struct rc_work;
-- 
2.20.1