From 2b38362bd3b8e0a3691f0a8e82444a54f702e384 Mon Sep 17 00:00:00 2001
From: Bitterblue Smith <rtl8821cerfe2@gmail.com>
Date: Fri, 8 Nov 2024 01:43:50 +0200
Subject: [PATCH 4/6] wifi: rtw88: usb: Enable RX aggregation for 8821au/8812au

USB RX aggregation improves the RX speed on certain ARM systems, like
the NanoPi NEO Core2. With RTL8811AU, before: 30 Mbps, after: 224 Mbps.

The out-of-tree driver uses aggregation size of 7 in USB 3 mode, but
that doesn't work here. rtw88 advertises support for receiving AMSDU
in AMPDU, so the AP sends larger frames, up to ~5100 bytes. With a size
of 7 RTL8812AU frequently tries to aggregate more frames than will fit
in 32768 bytes. Use a size of 6 instead.

Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
---
 drivers/net/wireless/realtek/rtw88/usb.c | 30 ++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

--- a/drivers/net/wireless/realtek/rtw88/usb.c
+++ b/drivers/net/wireless/realtek/rtw88/usb.c
@@ -789,6 +789,32 @@ static void rtw_usb_dynamic_rx_agg_v1(st
 	rtw_write16(rtwdev, REG_RXDMA_AGG_PG_TH, val16);
 }
 
+static void rtw_usb_dynamic_rx_agg_v2(struct rtw_dev *rtwdev, bool enable)
+{
+	struct rtw_usb *rtwusb = rtw_get_usb_priv(rtwdev);
+	u8 size, timeout;
+	u16 val16;
+
+	if (rtwusb->udev->speed == USB_SPEED_SUPER) {
+		size = 0x6;
+		timeout = 0x1a;
+	} else {
+		size = 0x5;
+		timeout = 0x20;
+	}
+
+	if (!enable) {
+		size = 0x0;
+		timeout = 0x1;
+	}
+
+	val16 = u16_encode_bits(size, BIT_RXDMA_AGG_PG_TH) |
+		u16_encode_bits(timeout, BIT_DMA_AGG_TO_V1);
+
+	rtw_write16(rtwdev, REG_RXDMA_AGG_PG_TH, val16);
+	rtw_write8_set(rtwdev, REG_TXDMA_PQ_MAP, BIT_RXDMA_AGG_EN);
+}
+
 static void rtw_usb_dynamic_rx_agg(struct rtw_dev *rtwdev, bool enable)
 {
 	switch (rtwdev->chip->id) {
@@ -797,6 +823,10 @@ static void rtw_usb_dynamic_rx_agg(struc
 	case RTW_CHIP_TYPE_8821C:
 		rtw_usb_dynamic_rx_agg_v1(rtwdev, enable);
 		break;
+	case RTW_CHIP_TYPE_8821A:
+	case RTW_CHIP_TYPE_8812A:
+		rtw_usb_dynamic_rx_agg_v2(rtwdev, enable);
+		break;
 	case RTW_CHIP_TYPE_8723D:
 		/* Doesn't like aggregation. */
 		break;
