rtw88: add dump fw crash log

This patch adds a function which is able to dump firmware fifo when
firmware crashes. If firmware needs more than one time to dump all logs,
it will set a bit called "more bit" in the header of the first log, and
driver needs to set a register to inform firmware that it is ready for the
next dump.

Signed-off-by: Tzu-En Huang <tehuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200925061219.23754-5-tehuang@realtek.com

drivers/net/wireless/realtek/rtw88/fw.h

@@ -507,6 +507,20 @@ static inline void rtw_h2c_pkt_set_header(u8 *h2c_pkt, u8 sub_id)
 #define SET_NLO_LOC_NLO_INFO(h2c_pkt, value)                                   \
 	le32p_replace_bits((__le32 *)(h2c_pkt) + 0x00, value, GENMASK(23, 16))
 
+#define GET_FW_DUMP_LEN(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x00), GENMASK(15, 0))
+#define GET_FW_DUMP_SEQ(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x00), GENMASK(22, 16))
+#define GET_FW_DUMP_MORE(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x00), BIT(23))
+#define GET_FW_DUMP_VERSION(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x00), GENMASK(31, 24))
+#define GET_FW_DUMP_TLV_TYPE(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x01), GENMASK(15, 0))
+#define GET_FW_DUMP_TLV_LEN(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x01), GENMASK(31, 16))
+#define GET_FW_DUMP_TLV_VAL(_header)					\
+	le32_get_bits(*((__le32 *)(_header) + 0x02), GENMASK(31, 0))
 static inline struct rtw_c2h_cmd *get_c2h_from_skb(struct sk_buff *skb)
 {
 	u32 pkt_offset;

drivers/net/wireless/realtek/rtw88/main.c

@@ -317,6 +317,56 @@ void rtw_sta_remove(struct rtw_dev *rtwdev, struct ieee80211_sta *sta,
 		 sta->addr, si->mac_id);
 }
 
+static bool rtw_fw_dump_crash_log(struct rtw_dev *rtwdev)
+{
+	u32 size = rtwdev->chip->fw_rxff_size;
+	u32 *buf;
+	u8 seq;
+	bool ret = true;
+
+	buf = vmalloc(size);
+	if (!buf)
+		goto exit;
+
+	if (rtw_fw_dump_fifo(rtwdev, RTW_FW_FIFO_SEL_RXBUF_FW, 0, size, buf)) {
+		rtw_dbg(rtwdev, RTW_DBG_FW, "dump fw fifo fail\n");
+		goto free_buf;
+	}
+
+	if (GET_FW_DUMP_LEN(buf) == 0) {
+		rtw_dbg(rtwdev, RTW_DBG_FW, "fw crash dump's length is 0\n");
+		goto free_buf;
+	}
+
+	seq = GET_FW_DUMP_SEQ(buf);
+	if (seq > 0 && seq != (rtwdev->fw.prev_dump_seq + 1)) {
+		rtw_dbg(rtwdev, RTW_DBG_FW,
+			"fw crash dump's seq is wrong: %d\n", seq);
+		goto free_buf;
+	}
+	if (seq == 0 &&
+	    (GET_FW_DUMP_TLV_TYPE(buf) != FW_CD_TYPE ||
+	     GET_FW_DUMP_TLV_LEN(buf) != FW_CD_LEN ||
+	     GET_FW_DUMP_TLV_VAL(buf) != FW_CD_VAL)) {
+		rtw_dbg(rtwdev, RTW_DBG_FW, "fw crash dump's tlv is wrong\n");
+		goto free_buf;
+	}
+
+	print_hex_dump_bytes("rtw88 fw dump: ", DUMP_PREFIX_OFFSET, buf, size);
+
+	if (GET_FW_DUMP_MORE(buf) == 1) {
+		rtwdev->fw.prev_dump_seq = seq;
+		ret = false;
+	}
+
+free_buf:
+	vfree(buf);
+exit:
+	rtw_write8(rtwdev, REG_MCU_TST_CFG, 0);
+
+	return ret;
+}
+
 void rtw_vif_assoc_changed(struct rtw_vif *rtwvif,
 			   struct ieee80211_bss_conf *conf)
 {
@@ -373,6 +423,17 @@ static void rtw_fw_recovery_work(struct work_struct *work)
 	struct rtw_dev *rtwdev = container_of(work, struct rtw_dev,
 					      fw_recovery_work);
 
+	/* rtw_fw_dump_crash_log() returns false indicates that there are
+	 * still more log to dump. Driver set 0x1cf[7:0] = 0x1 to tell firmware
+	 * to dump the remaining part of the log, and firmware will trigger an
+	 * IMR_C2HCMD interrupt to inform driver the log is ready.
+	 */
+	if (!rtw_fw_dump_crash_log(rtwdev)) {
+		rtw_write8(rtwdev, REG_HRCV_MSG, 1);
+		return;
+	}
+	rtwdev->fw.prev_dump_seq = 0;
+
 	WARN(1, "firmware crash, start reset and recover\n");
 
 	mutex_lock(&rtwdev->mutex);

drivers/net/wireless/realtek/rtw88/main.h

@@ -1621,6 +1621,9 @@ struct rtw_fifo_conf {
 	const struct rtw_rqpn *rqpn;
 };
 
+#define FW_CD_TYPE 0xffff
+#define FW_CD_LEN 4
+#define FW_CD_VAL 0xaabbccdd
 struct rtw_fw_state {
 	const struct firmware *firmware;
 	struct rtw_dev *rtwdev;
@@ -1629,6 +1632,7 @@ struct rtw_fw_state {
 	u8 sub_version;
 	u8 sub_index;
 	u16 h2c_version;
+	u8 prev_dump_seq;
 };
 
 struct rtw_hal {

drivers/net/wireless/realtek/rtw88/reg.h

@@ -619,6 +619,8 @@
 #define BIT_ANAPAR_BTPS	BIT(22)
 #define REG_RSTB_SEL	0x1c38
 
+#define REG_HRCV_MSG	0x1cf
+
 #define REG_IGN_GNTBT4	0x4160
 
 #define RF_MODE		0x00