bnxt_en: Add support to collect crash dump via ethtool

Driver supports 2 types of core dumps.

1. Live dump - Firmware dump when system is up and running.
2. Crash dump - Dump which is collected during firmware crash
                that can be retrieved after recovery.
Crash dump is currently supported only on specific 58800 chips
which can be retrieved using OP-TEE API only, as firmware cannot
access this region directly.

User needs to set the dump flag using following command before
initiating the dump collection:

    $ ethtool -W|--set-dump eth0 N

Where N is "0" for live dump and "1" for crash dump

Command to collect the dump after setting the flag:

    $ ethtool -w eth0 data Filename

v3: Modify set_dump to support even when CONFIG_TEE_BNXT_FW=n.
Also change log message to netdev_info().

Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Signed-off-by: Sheetal Tigadoli <sheetal.tigadoli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1807,6 +1807,9 @@ struct bnxt {
 
 	u8			num_leds;
 	struct bnxt_led_info	leds[BNXT_MAX_LED];
+	u16			dump_flag;
+#define BNXT_DUMP_LIVE		0
+#define BNXT_DUMP_CRASH		1
 
 	struct bpf_prog		*xdp_prog;
 

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -3311,6 +3311,24 @@ static int bnxt_get_coredump(struct bnxt *bp, void *buf, u32 *dump_len)
 	return rc;
 }
 
+static int bnxt_set_dump(struct net_device *dev, struct ethtool_dump *dump)
+{
+	struct bnxt *bp = netdev_priv(dev);
+
+	if (dump->flag > BNXT_DUMP_CRASH) {
+		netdev_info(dev, "Supports only Live(0) and Crash(1) dumps.\n");
+		return -EINVAL;
+	}
+
+	if (!IS_ENABLED(CONFIG_TEE_BNXT_FW) && dump->flag == BNXT_DUMP_CRASH) {
+		netdev_info(dev, "Cannot collect crash dump as TEE_BNXT_FW config option is not enabled.\n");
+		return -EOPNOTSUPP;
+	}
+
+	bp->dump_flag = dump->flag;
+	return 0;
+}
+
 static int bnxt_get_dump_flag(struct net_device *dev, struct ethtool_dump *dump)
 {
 	struct bnxt *bp = netdev_priv(dev);
@@ -3323,7 +3341,12 @@ static int bnxt_get_dump_flag(struct net_device *dev, struct ethtool_dump *dump)
 			bp->ver_resp.hwrm_fw_bld_8b << 8 |
 			bp->ver_resp.hwrm_fw_rsvd_8b;
 
-	return bnxt_get_coredump(bp, NULL, &dump->len);
+	dump->flag = bp->dump_flag;
+	if (bp->dump_flag == BNXT_DUMP_CRASH)
+		dump->len = BNXT_CRASH_DUMP_LEN;
+	else
+		bnxt_get_coredump(bp, NULL, &dump->len);
+	return 0;
 }
 
 static int bnxt_get_dump_data(struct net_device *dev, struct ethtool_dump *dump,
@@ -3336,7 +3359,16 @@ static int bnxt_get_dump_data(struct net_device *dev, struct ethtool_dump *dump,
 
 	memset(buf, 0, dump->len);
 
-	return bnxt_get_coredump(bp, buf, &dump->len);
+	dump->flag = bp->dump_flag;
+	if (dump->flag == BNXT_DUMP_CRASH) {
+#ifdef CONFIG_TEE_BNXT_FW
+		return tee_bnxt_copy_coredump(buf, 0, dump->len);
+#endif
+	} else {
+		return bnxt_get_coredump(bp, buf, &dump->len);
+	}
+
+	return 0;
 }
 
 void bnxt_ethtool_init(struct bnxt *bp)
@@ -3446,6 +3478,7 @@ const struct ethtool_ops bnxt_ethtool_ops = {
 	.set_phys_id		= bnxt_set_phys_id,
 	.self_test		= bnxt_self_test,
 	.reset			= bnxt_reset,
+	.set_dump		= bnxt_set_dump,
 	.get_dump_flag		= bnxt_get_dump_flag,
 	.get_dump_data		= bnxt_get_dump_data,
 };

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.h

@@ -59,6 +59,8 @@ struct hwrm_dbg_cmn_output {
 	#define HWRM_DBG_CMN_FLAGS_MORE	1
 };
 
+#define BNXT_CRASH_DUMP_LEN	(8 << 20)
+
 #define BNXT_LED_DFLT_ENA				\
 	(PORT_LED_CFG_REQ_ENABLES_LED0_ID |		\
 	 PORT_LED_CFG_REQ_ENABLES_LED0_STATE |		\