wifi: rtw89: limit the PPDU length for VHT rate to 0x40000

JIRA: https://issues.redhat.com/browse/RHEL-35542

commit 1244109
Author: Chia-Yuan Li <[email protected]>
Date:   Thu Aug 15 21:40:54 2024 +0800

    wifi: rtw89: limit the PPDU length for VHT rate to 0x40000

    If the PPDU length for VHT rate exceeds 0x40000, calculating the PSDU
    length will overflow. TMAC will determine the length to be too small and
    as a result, all packets will be sent as ZLD (Zero Length Delimiter).

    Fixes: 5f7e92c ("wifi: rtw89: 8852b: set AMSDU limit to 5000")
Signed-off-by: Chia-Yuan Li <[email protected]>
Signed-off-by: Ping-Ke Shih <[email protected]>
    Link: https://patch.msgid.link/[email protected]

Signed-off-by: Narpat Mali <[email protected]>

Author: Narpat Mali

drivers/net/wireless/realtek/rtw89/mac.c

@@ -2723,6 +2723,7 @@ bool rtw89_mac_is_qta_dbcc(struct rtw89_dev *rtwdev, enum rtw89_qta_mode mode)
 
 static int ptcl_init_ax(struct rtw89_dev *rtwdev, u8 mac_idx)
 {
+	enum rtw89_core_chip_id chip_id = rtwdev->chip->chip_id;
 	u32 val, reg;
 	int ret;
 
@@ -2761,6 +2762,12 @@ static int ptcl_init_ax(struct rtw89_dev *rtwdev, u8 mac_idx)
 				  B_AX_SPE_RPT_PATH_MASK, FWD_TO_WLCPU);
 	}
 
+	if (chip_id == RTL8852A || rtw89_is_rtl885xb(rtwdev)) {
+		reg = rtw89_mac_reg_by_idx(rtwdev, R_AX_AGG_LEN_VHT_0, mac_idx);
+		rtw89_write32_mask(rtwdev, reg,
+				   B_AX_AMPDU_MAX_LEN_VHT_MASK, 0x3FF80);
+	}
+
 	return 0;
 }
 

drivers/net/wireless/realtek/rtw89/reg.h

@@ -2435,6 +2435,10 @@
 #define B_AX_RTS_TXTIME_TH_MASK GENMASK(15, 8)
 #define B_AX_RTS_LEN_TH_MASK GENMASK(7, 0)
 
+#define R_AX_AGG_LEN_VHT_0 0xC618
+#define R_AX_AGG_LEN_VHT_0_C1 0xE618
+#define B_AX_AMPDU_MAX_LEN_VHT_MASK GENMASK(19, 0)
+
 #define S_AX_CTS2S_TH_SEC_256B 1
 #define R_AX_SIFS_SETTING 0xC624
 #define R_AX_SIFS_SETTING_C1 0xE624