staging/rdma/hfi1: Tune for unknown channel if configuration file is absent

Currently, the driver fails to tune the SerDes and therefore prevents
link up if the configuration file is missing or fails parsing or
validation. This patch adds a fallback option so that the 8051 is asked
to tune for an unknown channel and possibly get the link up if tuning
succeeds. It also adds a user-friendly message to update the
configuration file if it is out-of-date.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 50 insertions, 47 deletions

diff --git a/drivers/staging/rdma/hfi1/platform.c b/drivers/staging/rdma/hfi1/platform.c
index 0309c5238823..2f07becb0b96 100644
--- a/drivers/staging/rdma/hfi1/platform.c
+++ b/drivers/staging/rdma/hfi1/platform.c
@@ -498,14 +498,14 @@ static void apply_rx_amplitude_settings(
 
 #define OPA_INVALID_INDEX 0xFFF
 
-static void apply_tx_lanes(struct hfi1_pportdata *ppd, u32 config_data,
-			   const char *message)
+static void apply_tx_lanes(struct hfi1_pportdata *ppd, u8 field_id,
+			   u32 config_data, const char *message)
 {
 	u8 i;
 	int ret = HCMD_SUCCESS;
 
 	for (i = 0; i < 4; i++) {
-		ret = load_8051_config(ppd->dd, 0, i, config_data);
+		ret = load_8051_config(ppd->dd, field_id, i, config_data);
 		if (ret != HCMD_SUCCESS) {
 			dd_dev_err(
 				ppd->dd,
@@ -524,6 +524,7 @@ static void apply_tunings(
 	u8 precur = 0, attn = 0, postcur = 0, external_device_config = 0;
 	u8 *cache = ppd->qsfp_info.cache;
 
+	/* Enable external device config if channel is limiting active */
 	read_8051_config(ppd->dd, LINK_OPTIMIZATION_SETTINGS,
 			 GENERAL_CONFIG, &config_data);
 	config_data |= limiting_active;
@@ -536,6 +537,7 @@ static void apply_tunings(
 			__func__);
 
 	config_data = 0; /* re-init  */
+	/* Pass tuning method to 8051 */
 	read_8051_config(ppd->dd, LINK_TUNING_PARAMETERS, GENERAL_CONFIG,
 			 &config_data);
 	config_data |= tuning_method;
@@ -545,47 +547,39 @@ static void apply_tunings(
 		dd_dev_err(ppd->dd, "%s: Failed to set tuning method\n",
 			   __func__);
 
-	external_device_config =
-		((cache[QSFP_MOD_PWR_OFFS] & 0x4) << 3) |
-		((cache[QSFP_MOD_PWR_OFFS] & 0x8) << 2) |
-		((cache[QSFP_EQ_INFO_OFFS] & 0x2) << 1) |
-		(cache[QSFP_EQ_INFO_OFFS] & 0x4);
-
-	config_data = 0; /* re-init  */
-	read_8051_config(ppd->dd, DC_HOST_COMM_SETTINGS, GENERAL_CONFIG,
-			 &config_data);
-	config_data |= (external_device_config << 24);
-	ret = load_8051_config(ppd->dd, DC_HOST_COMM_SETTINGS, GENERAL_CONFIG,
-			       config_data);
-	if (ret != HCMD_SUCCESS)
-		dd_dev_err(
-			ppd->dd,
-			"%s: Failed to set external device config parameters\n",
-			__func__);
-
-	config_data = 0; /* re-init  */
-	read_8051_config(ppd->dd, TX_SETTINGS, GENERAL_CONFIG, &config_data);
-	if ((ppd->link_speed_supported & OPA_LINK_SPEED_25G) &&
-	    (ppd->link_speed_enabled & OPA_LINK_SPEED_25G))
-		config_data |= 0x02;
-	if ((ppd->link_speed_supported & OPA_LINK_SPEED_12_5G) &&
-	    (ppd->link_speed_enabled & OPA_LINK_SPEED_12_5G))
-		config_data |= 0x01;
-	ret = load_8051_config(ppd->dd, TX_SETTINGS, GENERAL_CONFIG,
-			       config_data);
-	if (ret != HCMD_SUCCESS)
-		dd_dev_err(
-			ppd->dd,
-			"%s: Failed to set external device config parameters\n",
-			__func__);
-
-	config_data = (total_atten << 8) | (total_atten);
-
-	apply_tx_lanes(ppd, config_data, "Setting channel loss");
+	/* Set same channel loss for both TX and RX */
+	config_data = 0 | (total_atten << 16) | (total_atten << 24);
+	apply_tx_lanes(ppd, CHANNEL_LOSS_SETTINGS, config_data,
+		       "Setting channel loss");
+
+	/* Inform 8051 of cable capabilities */
+	if (ppd->qsfp_info.cache_valid) {
+		external_device_config =
+			((cache[QSFP_MOD_PWR_OFFS] & 0x4) << 3) |
+			((cache[QSFP_MOD_PWR_OFFS] & 0x8) << 2) |
+			((cache[QSFP_EQ_INFO_OFFS] & 0x2) << 1) |
+			(cache[QSFP_EQ_INFO_OFFS] & 0x4);
+		ret = read_8051_config(ppd->dd, DC_HOST_COMM_SETTINGS,
+				       GENERAL_CONFIG, &config_data);
+		/* Clear, then set the external device config field */
+		config_data &= ~(0xFF << 24);
+		config_data |= (external_device_config << 24);
+		ret = load_8051_config(ppd->dd, DC_HOST_COMM_SETTINGS,
+				       GENERAL_CONFIG, config_data);
+		if (ret != HCMD_SUCCESS)
+			dd_dev_info(ppd->dd,
+				    "%s: Failed set ext device config params\n",
+				    __func__);
+	}
 
-	if (tx_preset_index == OPA_INVALID_INDEX)
+	if (tx_preset_index == OPA_INVALID_INDEX) {
+		if (ppd->port_type == PORT_TYPE_QSFP && limiting_active)
+			dd_dev_info(ppd->dd, "%s: Invalid Tx preset index\n",
+				    __func__);
 		return;
+	}
 
+	/* Following for limiting active channels only */
 	get_platform_config_field(
 		ppd->dd, PLATFORM_CONFIG_TX_PRESET_TABLE, tx_preset_index,
 		TX_PRESET_TABLE_PRECUR, &tx_preset, 4);
@@ -603,7 +597,8 @@ static void apply_tunings(
 
 	config_data = precur | (attn << 8) | (postcur << 16);
 
-	apply_tx_lanes(ppd, config_data, "Applying TX settings");
+	apply_tx_lanes(ppd, TX_EQ_SETTINGS, config_data,
+		       "Applying TX settings");
 }
 
 static int tune_active_qsfp(struct hfi1_pportdata *ppd, u32 *ptr_tx_preset,
@@ -766,7 +761,7 @@ void tune_serdes(struct hfi1_pportdata *ppd)
 	u32 total_atten = 0;
 	u32 remote_atten = 0, platform_atten = 0;
 	u32 rx_preset_index, tx_preset_index;
-	u8 tuning_method = 0;
+	u8 tuning_method = 0, limiting_active = 0;
 	struct hfi1_devdata *dd = ppd->dd;
 
 	rx_preset_index = OPA_INVALID_INDEX;
@@ -789,7 +784,7 @@ void tune_serdes(struct hfi1_pportdata *ppd)
 					PORT_TABLE_PORT_TYPE, &ppd->port_type,
 					4);
 	if (ret)
-		goto bail;
+		ppd->port_type = PORT_TYPE_UNKNOWN;
 
 	switch (ppd->port_type) {
 	case PORT_TYPE_DISCONNECTED:
@@ -853,6 +848,9 @@ void tune_serdes(struct hfi1_pportdata *ppd)
 				refresh_qsfp_cache(ppd, &ppd->qsfp_info);
 				if (ret)
 					goto bail;
+
+				limiting_active =
+						ppd->qsfp_info.limiting_active;
 			} else {
 				dd_dev_err(dd,
 					   "%s: Reading QSFP memory failed\n",
@@ -866,13 +864,18 @@ void tune_serdes(struct hfi1_pportdata *ppd)
 		break;
 	default:
 		dd_dev_info(ppd->dd, "%s: Unknown port type\n", __func__);
-		goto bail;
+		ppd->port_type = PORT_TYPE_UNKNOWN;
+		tuning_method = OPA_UNKNOWN_TUNING;
+		total_atten = 0;
+		limiting_active = 0;
+		tx_preset_index = OPA_INVALID_INDEX;
+		break;
 	}
+
 	if (ppd->offline_disabled_reason ==
 			HFI1_ODR_MASK(OPA_LINKDOWN_REASON_NONE))
 		apply_tunings(ppd, tx_preset_index, tuning_method,
-			      total_atten,
-			      ppd->qsfp_info.limiting_active);
+			      total_atten, limiting_active);
 
 	if (!ret)
 		ppd->driver_link_ready = 1;