Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1035 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/hfi1/platform.c b/drivers/infiniband/hw/hfi1/platform.c
new file mode 100644
index 000000000..54cbd8f1a
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/platform.c
@@ -0,0 +1,1035 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+/*
+ * Copyright(c) 2015, 2016 Intel Corporation.
+ */
+
+#include <linux/firmware.h>
+
+#include "hfi.h"
+#include "efivar.h"
+#include "eprom.h"
+
+#define DEFAULT_PLATFORM_CONFIG_NAME "hfi1_platform.dat"
+
+static int validate_scratch_checksum(struct hfi1_devdata *dd)
+{
+	u64 checksum = 0, temp_scratch = 0;
+	int i, j, version;
+
+	temp_scratch = read_csr(dd, ASIC_CFG_SCRATCH);
+	version = (temp_scratch & BITMAP_VERSION_SMASK) >> BITMAP_VERSION_SHIFT;
+
+	/* Prevent power on default of all zeroes from passing checksum */
+	if (!version) {
+		dd_dev_err(dd, "%s: Config bitmap uninitialized\n", __func__);
+		dd_dev_err(dd,
+			   "%s: Please update your BIOS to support active channels\n",
+			   __func__);
+		return 0;
+	}
+
+	/*
+	 * ASIC scratch 0 only contains the checksum and bitmap version as
+	 * fields of interest, both of which are handled separately from the
+	 * loop below, so skip it
+	 */
+	checksum += version;
+	for (i = 1; i < ASIC_NUM_SCRATCH; i++) {
+		temp_scratch = read_csr(dd, ASIC_CFG_SCRATCH + (8 * i));
+		for (j = sizeof(u64); j != 0; j -= 2) {
+			checksum += (temp_scratch & 0xFFFF);
+			temp_scratch >>= 16;
+		}
+	}
+
+	while (checksum >> 16)
+		checksum = (checksum & CHECKSUM_MASK) + (checksum >> 16);
+
+	temp_scratch = read_csr(dd, ASIC_CFG_SCRATCH);
+	temp_scratch &= CHECKSUM_SMASK;
+	temp_scratch >>= CHECKSUM_SHIFT;
+
+	if (checksum + temp_scratch == 0xFFFF)
+		return 1;
+
+	dd_dev_err(dd, "%s: Configuration bitmap corrupted\n", __func__);
+	return 0;
+}
+
+static void save_platform_config_fields(struct hfi1_devdata *dd)
+{
+	struct hfi1_pportdata *ppd = dd->pport;
+	u64 temp_scratch = 0, temp_dest = 0;
+
+	temp_scratch = read_csr(dd, ASIC_CFG_SCRATCH_1);
+
+	temp_dest = temp_scratch &
+		    (dd->hfi1_id ? PORT1_PORT_TYPE_SMASK :
+		     PORT0_PORT_TYPE_SMASK);
+	ppd->port_type = temp_dest >>
+			 (dd->hfi1_id ? PORT1_PORT_TYPE_SHIFT :
+			  PORT0_PORT_TYPE_SHIFT);
+
+	temp_dest = temp_scratch &
+		    (dd->hfi1_id ? PORT1_LOCAL_ATTEN_SMASK :
+		     PORT0_LOCAL_ATTEN_SMASK);
+	ppd->local_atten = temp_dest >>
+			   (dd->hfi1_id ? PORT1_LOCAL_ATTEN_SHIFT :
+			    PORT0_LOCAL_ATTEN_SHIFT);
+
+	temp_dest = temp_scratch &
+		    (dd->hfi1_id ? PORT1_REMOTE_ATTEN_SMASK :
+		     PORT0_REMOTE_ATTEN_SMASK);
+	ppd->remote_atten = temp_dest >>
+			    (dd->hfi1_id ? PORT1_REMOTE_ATTEN_SHIFT :
+			     PORT0_REMOTE_ATTEN_SHIFT);
+
+	temp_dest = temp_scratch &
+		    (dd->hfi1_id ? PORT1_DEFAULT_ATTEN_SMASK :
+		     PORT0_DEFAULT_ATTEN_SMASK);
+	ppd->default_atten = temp_dest >>
+			     (dd->hfi1_id ? PORT1_DEFAULT_ATTEN_SHIFT :
+			      PORT0_DEFAULT_ATTEN_SHIFT);
+
+	temp_scratch = read_csr(dd, dd->hfi1_id ? ASIC_CFG_SCRATCH_3 :
+				ASIC_CFG_SCRATCH_2);
+
+	ppd->tx_preset_eq = (temp_scratch & TX_EQ_SMASK) >> TX_EQ_SHIFT;
+	ppd->tx_preset_noeq = (temp_scratch & TX_NO_EQ_SMASK) >> TX_NO_EQ_SHIFT;
+	ppd->rx_preset = (temp_scratch & RX_SMASK) >> RX_SHIFT;
+
+	ppd->max_power_class = (temp_scratch & QSFP_MAX_POWER_SMASK) >>
+				QSFP_MAX_POWER_SHIFT;
+
+	ppd->config_from_scratch = true;
+}
+
+void get_platform_config(struct hfi1_devdata *dd)
+{
+	int ret = 0;
+	u8 *temp_platform_config = NULL;
+	u32 esize;
+	const struct firmware *platform_config_file = NULL;
+
+	if (is_integrated(dd)) {
+		if (validate_scratch_checksum(dd)) {
+			save_platform_config_fields(dd);
+			return;
+		}
+	} else {
+		ret = eprom_read_platform_config(dd,
+						 (void **)&temp_platform_config,
+						 &esize);
+		if (!ret) {
+			/* success */
+			dd->platform_config.data = temp_platform_config;
+			dd->platform_config.size = esize;
+			return;
+		}
+	}
+	dd_dev_err(dd,
+		   "%s: Failed to get platform config, falling back to sub-optimal default file\n",
+		   __func__);
+
+	ret = request_firmware(&platform_config_file,
+			       DEFAULT_PLATFORM_CONFIG_NAME,
+			       &dd->pcidev->dev);
+	if (ret) {
+		dd_dev_err(dd,
+			   "%s: No default platform config file found\n",
+			   __func__);
+		return;
+	}
+
+	/*
+	 * Allocate separate memory block to store data and free firmware
+	 * structure. This allows free_platform_config to treat EPROM and
+	 * fallback configs in the same manner.
+	 */
+	dd->platform_config.data = kmemdup(platform_config_file->data,
+					   platform_config_file->size,
+					   GFP_KERNEL);
+	dd->platform_config.size = platform_config_file->size;
+	release_firmware(platform_config_file);
+}
+
+void free_platform_config(struct hfi1_devdata *dd)
+{
+	/* Release memory allocated for eprom or fallback file read. */
+	kfree(dd->platform_config.data);
+	dd->platform_config.data = NULL;
+}
+
+void get_port_type(struct hfi1_pportdata *ppd)
+{
+	int ret;
+	u32 temp;
+
+	ret = get_platform_config_field(ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+					PORT_TABLE_PORT_TYPE, &temp,
+					4);
+	if (ret) {
+		ppd->port_type = PORT_TYPE_UNKNOWN;
+		return;
+	}
+	ppd->port_type = temp;
+}
+
+int set_qsfp_tx(struct hfi1_pportdata *ppd, int on)
+{
+	u8 tx_ctrl_byte = on ? 0x0 : 0xF;
+	int ret = 0;
+
+	ret = qsfp_write(ppd, ppd->dd->hfi1_id, QSFP_TX_CTRL_BYTE_OFFS,
+			 &tx_ctrl_byte, 1);
+	/* we expected 1, so consider 0 an error */
+	if (ret == 0)
+		ret = -EIO;
+	else if (ret == 1)
+		ret = 0;
+	return ret;
+}
+
+static int qual_power(struct hfi1_pportdata *ppd)
+{
+	u32 cable_power_class = 0, power_class_max = 0;
+	u8 *cache = ppd->qsfp_info.cache;
+	int ret = 0;
+
+	ret = get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_SYSTEM_TABLE, 0,
+		SYSTEM_TABLE_QSFP_POWER_CLASS_MAX, &power_class_max, 4);
+	if (ret)
+		return ret;
+
+	cable_power_class = get_qsfp_power_class(cache[QSFP_MOD_PWR_OFFS]);
+
+	if (cable_power_class > power_class_max)
+		ppd->offline_disabled_reason =
+			HFI1_ODR_MASK(OPA_LINKDOWN_REASON_POWER_POLICY);
+
+	if (ppd->offline_disabled_reason ==
+			HFI1_ODR_MASK(OPA_LINKDOWN_REASON_POWER_POLICY)) {
+		dd_dev_err(
+			ppd->dd,
+			"%s: Port disabled due to system power restrictions\n",
+			__func__);
+		ret = -EPERM;
+	}
+	return ret;
+}
+
+static int qual_bitrate(struct hfi1_pportdata *ppd)
+{
+	u16 lss = ppd->link_speed_supported, lse = ppd->link_speed_enabled;
+	u8 *cache = ppd->qsfp_info.cache;
+
+	if ((lss & OPA_LINK_SPEED_25G) && (lse & OPA_LINK_SPEED_25G) &&
+	    cache[QSFP_NOM_BIT_RATE_250_OFFS] < 0x64)
+		ppd->offline_disabled_reason =
+			   HFI1_ODR_MASK(OPA_LINKDOWN_REASON_LINKSPEED_POLICY);
+
+	if ((lss & OPA_LINK_SPEED_12_5G) && (lse & OPA_LINK_SPEED_12_5G) &&
+	    cache[QSFP_NOM_BIT_RATE_100_OFFS] < 0x7D)
+		ppd->offline_disabled_reason =
+			   HFI1_ODR_MASK(OPA_LINKDOWN_REASON_LINKSPEED_POLICY);
+
+	if (ppd->offline_disabled_reason ==
+			HFI1_ODR_MASK(OPA_LINKDOWN_REASON_LINKSPEED_POLICY)) {
+		dd_dev_err(
+			ppd->dd,
+			"%s: Cable failed bitrate check, disabling port\n",
+			__func__);
+		return -EPERM;
+	}
+	return 0;
+}
+
+static int set_qsfp_high_power(struct hfi1_pportdata *ppd)
+{
+	u8 cable_power_class = 0, power_ctrl_byte = 0;
+	u8 *cache = ppd->qsfp_info.cache;
+	int ret;
+
+	cable_power_class = get_qsfp_power_class(cache[QSFP_MOD_PWR_OFFS]);
+
+	if (cable_power_class > QSFP_POWER_CLASS_1) {
+		power_ctrl_byte = cache[QSFP_PWR_CTRL_BYTE_OFFS];
+
+		power_ctrl_byte |= 1;
+		power_ctrl_byte &= ~(0x2);
+
+		ret = qsfp_write(ppd, ppd->dd->hfi1_id,
+				 QSFP_PWR_CTRL_BYTE_OFFS,
+				 &power_ctrl_byte, 1);
+		if (ret != 1)
+			return -EIO;
+
+		if (cable_power_class > QSFP_POWER_CLASS_4) {
+			power_ctrl_byte |= (1 << 2);
+			ret = qsfp_write(ppd, ppd->dd->hfi1_id,
+					 QSFP_PWR_CTRL_BYTE_OFFS,
+					 &power_ctrl_byte, 1);
+			if (ret != 1)
+				return -EIO;
+		}
+
+		/* SFF 8679 rev 1.7 LPMode Deassert time */
+		msleep(300);
+	}
+	return 0;
+}
+
+static void apply_rx_cdr(struct hfi1_pportdata *ppd,
+			 u32 rx_preset_index,
+			 u8 *cdr_ctrl_byte)
+{
+	u32 rx_preset;
+	u8 *cache = ppd->qsfp_info.cache;
+	int cable_power_class;
+
+	if (!((cache[QSFP_MOD_PWR_OFFS] & 0x4) &&
+	      (cache[QSFP_CDR_INFO_OFFS] & 0x40)))
+		return;
+
+	/* RX CDR present, bypass supported */
+	cable_power_class = get_qsfp_power_class(cache[QSFP_MOD_PWR_OFFS]);
+
+	if (cable_power_class <= QSFP_POWER_CLASS_3) {
+		/* Power class <= 3, ignore config & turn RX CDR on */
+		*cdr_ctrl_byte |= 0xF;
+		return;
+	}
+
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_RX_PRESET_TABLE,
+		rx_preset_index, RX_PRESET_TABLE_QSFP_RX_CDR_APPLY,
+		&rx_preset, 4);
+
+	if (!rx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: RX_CDR_APPLY is set to disabled\n",
+			__func__);
+		return;
+	}
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_RX_PRESET_TABLE,
+		rx_preset_index, RX_PRESET_TABLE_QSFP_RX_CDR,
+		&rx_preset, 4);
+
+	/* Expand cdr setting to all 4 lanes */
+	rx_preset = (rx_preset | (rx_preset << 1) |
+			(rx_preset << 2) | (rx_preset << 3));
+
+	if (rx_preset) {
+		*cdr_ctrl_byte |= rx_preset;
+	} else {
+		*cdr_ctrl_byte &= rx_preset;
+		/* Preserve current TX CDR status */
+		*cdr_ctrl_byte |= (cache[QSFP_CDR_CTRL_BYTE_OFFS] & 0xF0);
+	}
+}
+
+static void apply_tx_cdr(struct hfi1_pportdata *ppd,
+			 u32 tx_preset_index,
+			 u8 *cdr_ctrl_byte)
+{
+	u32 tx_preset;
+	u8 *cache = ppd->qsfp_info.cache;
+	int cable_power_class;
+
+	if (!((cache[QSFP_MOD_PWR_OFFS] & 0x8) &&
+	      (cache[QSFP_CDR_INFO_OFFS] & 0x80)))
+		return;
+
+	/* TX CDR present, bypass supported */
+	cable_power_class = get_qsfp_power_class(cache[QSFP_MOD_PWR_OFFS]);
+
+	if (cable_power_class <= QSFP_POWER_CLASS_3) {
+		/* Power class <= 3, ignore config & turn TX CDR on */
+		*cdr_ctrl_byte |= 0xF0;
+		return;
+	}
+
+	get_platform_config_field(
+		ppd->dd,
+		PLATFORM_CONFIG_TX_PRESET_TABLE, tx_preset_index,
+		TX_PRESET_TABLE_QSFP_TX_CDR_APPLY, &tx_preset, 4);
+
+	if (!tx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: TX_CDR_APPLY is set to disabled\n",
+			__func__);
+		return;
+	}
+	get_platform_config_field(
+		ppd->dd,
+		PLATFORM_CONFIG_TX_PRESET_TABLE,
+		tx_preset_index,
+		TX_PRESET_TABLE_QSFP_TX_CDR, &tx_preset, 4);
+
+	/* Expand cdr setting to all 4 lanes */
+	tx_preset = (tx_preset | (tx_preset << 1) |
+			(tx_preset << 2) | (tx_preset << 3));
+
+	if (tx_preset)
+		*cdr_ctrl_byte |= (tx_preset << 4);
+	else
+		/* Preserve current/determined RX CDR status */
+		*cdr_ctrl_byte &= ((tx_preset << 4) | 0xF);
+}
+
+static void apply_cdr_settings(
+		struct hfi1_pportdata *ppd, u32 rx_preset_index,
+		u32 tx_preset_index)
+{
+	u8 *cache = ppd->qsfp_info.cache;
+	u8 cdr_ctrl_byte = cache[QSFP_CDR_CTRL_BYTE_OFFS];
+
+	apply_rx_cdr(ppd, rx_preset_index, &cdr_ctrl_byte);
+
+	apply_tx_cdr(ppd, tx_preset_index, &cdr_ctrl_byte);
+
+	qsfp_write(ppd, ppd->dd->hfi1_id, QSFP_CDR_CTRL_BYTE_OFFS,
+		   &cdr_ctrl_byte, 1);
+}
+
+static void apply_tx_eq_auto(struct hfi1_pportdata *ppd)
+{
+	u8 *cache = ppd->qsfp_info.cache;
+	u8 tx_eq;
+
+	if (!(cache[QSFP_EQ_INFO_OFFS] & 0x8))
+		return;
+	/* Disable adaptive TX EQ if present */
+	tx_eq = cache[(128 * 3) + 241];
+	tx_eq &= 0xF0;
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 241, &tx_eq, 1);
+}
+
+static void apply_tx_eq_prog(struct hfi1_pportdata *ppd, u32 tx_preset_index)
+{
+	u8 *cache = ppd->qsfp_info.cache;
+	u32 tx_preset;
+	u8 tx_eq;
+
+	if (!(cache[QSFP_EQ_INFO_OFFS] & 0x4))
+		return;
+
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_TX_PRESET_TABLE,
+		tx_preset_index, TX_PRESET_TABLE_QSFP_TX_EQ_APPLY,
+		&tx_preset, 4);
+	if (!tx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: TX_EQ_APPLY is set to disabled\n",
+			__func__);
+		return;
+	}
+	get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_TX_PRESET_TABLE,
+			tx_preset_index, TX_PRESET_TABLE_QSFP_TX_EQ,
+			&tx_preset, 4);
+
+	if (((cache[(128 * 3) + 224] & 0xF0) >> 4) < tx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: TX EQ %x unsupported\n",
+			__func__, tx_preset);
+
+		dd_dev_info(
+			ppd->dd,
+			"%s: Applying EQ %x\n",
+			__func__, cache[608] & 0xF0);
+
+		tx_preset = (cache[608] & 0xF0) >> 4;
+	}
+
+	tx_eq = tx_preset | (tx_preset << 4);
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 234, &tx_eq, 1);
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 235, &tx_eq, 1);
+}
+
+static void apply_rx_eq_emp(struct hfi1_pportdata *ppd, u32 rx_preset_index)
+{
+	u32 rx_preset;
+	u8 rx_eq, *cache = ppd->qsfp_info.cache;
+
+	if (!(cache[QSFP_EQ_INFO_OFFS] & 0x2))
+		return;
+	get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_RX_PRESET_TABLE,
+			rx_preset_index, RX_PRESET_TABLE_QSFP_RX_EMP_APPLY,
+			&rx_preset, 4);
+
+	if (!rx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: RX_EMP_APPLY is set to disabled\n",
+			__func__);
+		return;
+	}
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_RX_PRESET_TABLE,
+		rx_preset_index, RX_PRESET_TABLE_QSFP_RX_EMP,
+		&rx_preset, 4);
+
+	if ((cache[(128 * 3) + 224] & 0xF) < rx_preset) {
+		dd_dev_info(
+			ppd->dd,
+			"%s: Requested RX EMP %x\n",
+			__func__, rx_preset);
+
+		dd_dev_info(
+			ppd->dd,
+			"%s: Applying supported EMP %x\n",
+			__func__, cache[608] & 0xF);
+
+		rx_preset = cache[608] & 0xF;
+	}
+
+	rx_eq = rx_preset | (rx_preset << 4);
+
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 236, &rx_eq, 1);
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 237, &rx_eq, 1);
+}
+
+static void apply_eq_settings(struct hfi1_pportdata *ppd,
+			      u32 rx_preset_index, u32 tx_preset_index)
+{
+	u8 *cache = ppd->qsfp_info.cache;
+
+	/* no point going on w/o a page 3 */
+	if (cache[2] & 4) {
+		dd_dev_info(ppd->dd,
+			    "%s: Upper page 03 not present\n",
+			    __func__);
+		return;
+	}
+
+	apply_tx_eq_auto(ppd);
+
+	apply_tx_eq_prog(ppd, tx_preset_index);
+
+	apply_rx_eq_emp(ppd, rx_preset_index);
+}
+
+static void apply_rx_amplitude_settings(
+		struct hfi1_pportdata *ppd, u32 rx_preset_index,
+		u32 tx_preset_index)
+{
+	u32 rx_preset;
+	u8 rx_amp = 0, i = 0, preferred = 0, *cache = ppd->qsfp_info.cache;
+
+	/* no point going on w/o a page 3 */
+	if (cache[2] & 4) {
+		dd_dev_info(ppd->dd,
+			    "%s: Upper page 03 not present\n",
+			    __func__);
+		return;
+	}
+	if (!(cache[QSFP_EQ_INFO_OFFS] & 0x1)) {
+		dd_dev_info(ppd->dd,
+			    "%s: RX_AMP_APPLY is set to disabled\n",
+			    __func__);
+		return;
+	}
+
+	get_platform_config_field(ppd->dd,
+				  PLATFORM_CONFIG_RX_PRESET_TABLE,
+				  rx_preset_index,
+				  RX_PRESET_TABLE_QSFP_RX_AMP_APPLY,
+				  &rx_preset, 4);
+
+	if (!rx_preset) {
+		dd_dev_info(ppd->dd,
+			    "%s: RX_AMP_APPLY is set to disabled\n",
+			    __func__);
+		return;
+	}
+	get_platform_config_field(ppd->dd,
+				  PLATFORM_CONFIG_RX_PRESET_TABLE,
+				  rx_preset_index,
+				  RX_PRESET_TABLE_QSFP_RX_AMP,
+				  &rx_preset, 4);
+
+	dd_dev_info(ppd->dd,
+		    "%s: Requested RX AMP %x\n",
+		    __func__,
+		    rx_preset);
+
+	for (i = 0; i < 4; i++) {
+		if (cache[(128 * 3) + 225] & (1 << i)) {
+			preferred = i;
+			if (preferred == rx_preset)
+				break;
+		}
+	}
+
+	/*
+	 * Verify that preferred RX amplitude is not just a
+	 * fall through of the default
+	 */
+	if (!preferred && !(cache[(128 * 3) + 225] & 0x1)) {
+		dd_dev_info(ppd->dd, "No supported RX AMP, not applying\n");
+		return;
+	}
+
+	dd_dev_info(ppd->dd,
+		    "%s: Applying RX AMP %x\n", __func__, preferred);
+
+	rx_amp = preferred | (preferred << 4);
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 238, &rx_amp, 1);
+	qsfp_write(ppd, ppd->dd->hfi1_id, (256 * 3) + 239, &rx_amp, 1);
+}
+
+#define OPA_INVALID_INDEX 0xFFF
+
+static void apply_tx_lanes(struct hfi1_pportdata *ppd, u8 field_id,
+			   u32 config_data, const char *message)
+{
+	u8 i;
+	int ret;
+
+	for (i = 0; i < 4; i++) {
+		ret = load_8051_config(ppd->dd, field_id, i, config_data);
+		if (ret != HCMD_SUCCESS) {
+			dd_dev_err(
+				ppd->dd,
+				"%s: %s for lane %u failed\n",
+				message, __func__, i);
+		}
+	}
+}
+
+/*
+ * Return a special SerDes setting for low power AOC cables.  The power class
+ * threshold and setting being used were all found by empirical testing.
+ *
+ * Summary of the logic:
+ *
+ * if (QSFP and QSFP_TYPE == AOC and QSFP_POWER_CLASS < 4)
+ *     return 0xe
+ * return 0; // leave at default
+ */
+static u8 aoc_low_power_setting(struct hfi1_pportdata *ppd)
+{
+	u8 *cache = ppd->qsfp_info.cache;
+	int power_class;
+
+	/* QSFP only */
+	if (ppd->port_type != PORT_TYPE_QSFP)
+		return 0; /* leave at default */
+
+	/* active optical cables only */
+	switch ((cache[QSFP_MOD_TECH_OFFS] & 0xF0) >> 4) {
+	case 0x0 ... 0x9: fallthrough;
+	case 0xC: fallthrough;
+	case 0xE:
+		/* active AOC */
+		power_class = get_qsfp_power_class(cache[QSFP_MOD_PWR_OFFS]);
+		if (power_class < QSFP_POWER_CLASS_4)
+			return 0xe;
+	}
+	return 0; /* leave at default */
+}
+
+static void apply_tunings(
+		struct hfi1_pportdata *ppd, u32 tx_preset_index,
+		u8 tuning_method, u32 total_atten, u8 limiting_active)
+{
+	int ret = 0;
+	u32 config_data = 0, tx_preset = 0;
+	u8 precur = 0, attn = 0, postcur = 0, external_device_config = 0;
+	u8 *cache = ppd->qsfp_info.cache;
+
+	/* Pass tuning method to 8051 */
+	read_8051_config(ppd->dd, LINK_TUNING_PARAMETERS, GENERAL_CONFIG,
+			 &config_data);
+	config_data &= ~(0xff << TUNING_METHOD_SHIFT);
+	config_data |= ((u32)tuning_method << TUNING_METHOD_SHIFT);
+	ret = load_8051_config(ppd->dd, LINK_TUNING_PARAMETERS, GENERAL_CONFIG,
+			       config_data);
+	if (ret != HCMD_SUCCESS)
+		dd_dev_err(ppd->dd, "%s: Failed to set tuning method\n",
+			   __func__);
+
+	/* 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 &= ~(u32)0xFF;
+		config_data |= external_device_config;
+		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 set ext device config params\n",
+				   __func__);
+	}
+
+	if (tx_preset_index == OPA_INVALID_INDEX) {
+		if (ppd->port_type == PORT_TYPE_QSFP && limiting_active)
+			dd_dev_err(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);
+	precur = tx_preset;
+
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_TX_PRESET_TABLE,
+		tx_preset_index, TX_PRESET_TABLE_ATTN, &tx_preset, 4);
+	attn = tx_preset;
+
+	get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_TX_PRESET_TABLE,
+		tx_preset_index, TX_PRESET_TABLE_POSTCUR, &tx_preset, 4);
+	postcur = tx_preset;
+
+	/*
+	 * NOTES:
+	 * o The aoc_low_power_setting is applied to all lanes even
+	 *   though only lane 0's value is examined by the firmware.
+	 * o A lingering low power setting after a cable swap does
+	 *   not occur.  On cable unplug the 8051 is reset and
+	 *   restarted on cable insert.  This resets all settings to
+	 *   their default, erasing any previous low power setting.
+	 */
+	config_data = precur | (attn << 8) | (postcur << 16) |
+			(aoc_low_power_setting(ppd) << 24);
+
+	apply_tx_lanes(ppd, TX_EQ_SETTINGS, config_data,
+		       "Applying TX settings");
+}
+
+/* Must be holding the QSFP i2c resource */
+static int tune_active_qsfp(struct hfi1_pportdata *ppd, u32 *ptr_tx_preset,
+			    u32 *ptr_rx_preset, u32 *ptr_total_atten)
+{
+	int ret;
+	u16 lss = ppd->link_speed_supported, lse = ppd->link_speed_enabled;
+	u8 *cache = ppd->qsfp_info.cache;
+
+	ppd->qsfp_info.limiting_active = 1;
+
+	ret = set_qsfp_tx(ppd, 0);
+	if (ret)
+		return ret;
+
+	ret = qual_power(ppd);
+	if (ret)
+		return ret;
+
+	ret = qual_bitrate(ppd);
+	if (ret)
+		return ret;
+
+	/*
+	 * We'll change the QSFP memory contents from here on out, thus we set a
+	 * flag here to remind ourselves to reset the QSFP module. This prevents
+	 * reuse of stale settings established in our previous pass through.
+	 */
+	if (ppd->qsfp_info.reset_needed) {
+		ret = reset_qsfp(ppd);
+		if (ret)
+			return ret;
+		refresh_qsfp_cache(ppd, &ppd->qsfp_info);
+	} else {
+		ppd->qsfp_info.reset_needed = 1;
+	}
+
+	ret = set_qsfp_high_power(ppd);
+	if (ret)
+		return ret;
+
+	if (cache[QSFP_EQ_INFO_OFFS] & 0x4) {
+		ret = get_platform_config_field(
+			ppd->dd,
+			PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_TX_PRESET_IDX_ACTIVE_EQ,
+			ptr_tx_preset, 4);
+		if (ret) {
+			*ptr_tx_preset = OPA_INVALID_INDEX;
+			return ret;
+		}
+	} else {
+		ret = get_platform_config_field(
+			ppd->dd,
+			PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_TX_PRESET_IDX_ACTIVE_NO_EQ,
+			ptr_tx_preset, 4);
+		if (ret) {
+			*ptr_tx_preset = OPA_INVALID_INDEX;
+			return ret;
+		}
+	}
+
+	ret = get_platform_config_field(
+		ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+		PORT_TABLE_RX_PRESET_IDX, ptr_rx_preset, 4);
+	if (ret) {
+		*ptr_rx_preset = OPA_INVALID_INDEX;
+		return ret;
+	}
+
+	if ((lss & OPA_LINK_SPEED_25G) && (lse & OPA_LINK_SPEED_25G))
+		get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_LOCAL_ATTEN_25G, ptr_total_atten, 4);
+	else if ((lss & OPA_LINK_SPEED_12_5G) && (lse & OPA_LINK_SPEED_12_5G))
+		get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_LOCAL_ATTEN_12G, ptr_total_atten, 4);
+
+	apply_cdr_settings(ppd, *ptr_rx_preset, *ptr_tx_preset);
+
+	apply_eq_settings(ppd, *ptr_rx_preset, *ptr_tx_preset);
+
+	apply_rx_amplitude_settings(ppd, *ptr_rx_preset, *ptr_tx_preset);
+
+	ret = set_qsfp_tx(ppd, 1);
+
+	return ret;
+}
+
+static int tune_qsfp(struct hfi1_pportdata *ppd,
+		     u32 *ptr_tx_preset, u32 *ptr_rx_preset,
+		     u8 *ptr_tuning_method, u32 *ptr_total_atten)
+{
+	u32 cable_atten = 0, remote_atten = 0, platform_atten = 0;
+	u16 lss = ppd->link_speed_supported, lse = ppd->link_speed_enabled;
+	int ret = 0;
+	u8 *cache = ppd->qsfp_info.cache;
+
+	switch ((cache[QSFP_MOD_TECH_OFFS] & 0xF0) >> 4) {
+	case 0xA ... 0xB:
+		ret = get_platform_config_field(
+			ppd->dd,
+			PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_LOCAL_ATTEN_25G,
+			&platform_atten, 4);
+		if (ret)
+			return ret;
+
+		if ((lss & OPA_LINK_SPEED_25G) && (lse & OPA_LINK_SPEED_25G))
+			cable_atten = cache[QSFP_CU_ATTEN_12G_OFFS];
+		else if ((lss & OPA_LINK_SPEED_12_5G) &&
+			 (lse & OPA_LINK_SPEED_12_5G))
+			cable_atten = cache[QSFP_CU_ATTEN_7G_OFFS];
+
+		/* Fallback to configured attenuation if cable memory is bad */
+		if (cable_atten == 0 || cable_atten > 36) {
+			ret = get_platform_config_field(
+				ppd->dd,
+				PLATFORM_CONFIG_SYSTEM_TABLE, 0,
+				SYSTEM_TABLE_QSFP_ATTENUATION_DEFAULT_25G,
+				&cable_atten, 4);
+			if (ret)
+				return ret;
+		}
+
+		ret = get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_REMOTE_ATTEN_25G, &remote_atten, 4);
+		if (ret)
+			return ret;
+
+		*ptr_total_atten = platform_atten + cable_atten + remote_atten;
+
+		*ptr_tuning_method = OPA_PASSIVE_TUNING;
+		break;
+	case 0x0 ... 0x9: fallthrough;
+	case 0xC: fallthrough;
+	case 0xE:
+		ret = tune_active_qsfp(ppd, ptr_tx_preset, ptr_rx_preset,
+				       ptr_total_atten);
+		if (ret)
+			return ret;
+
+		*ptr_tuning_method = OPA_ACTIVE_TUNING;
+		break;
+	case 0xD: fallthrough;
+	case 0xF:
+	default:
+		dd_dev_warn(ppd->dd, "%s: Unknown/unsupported cable\n",
+			    __func__);
+		break;
+	}
+	return ret;
+}
+
+/*
+ * This function communicates its success or failure via ppd->driver_link_ready
+ * Thus, it depends on its association with start_link(...) which checks
+ * driver_link_ready before proceeding with the link negotiation and
+ * initialization process.
+ */
+void tune_serdes(struct hfi1_pportdata *ppd)
+{
+	int ret = 0;
+	u32 total_atten = 0;
+	u32 remote_atten = 0, platform_atten = 0;
+	u32 rx_preset_index, tx_preset_index;
+	u8 tuning_method = 0, limiting_active = 0;
+	struct hfi1_devdata *dd = ppd->dd;
+
+	rx_preset_index = OPA_INVALID_INDEX;
+	tx_preset_index = OPA_INVALID_INDEX;
+
+	/* the link defaults to enabled */
+	ppd->link_enabled = 1;
+	/* the driver link ready state defaults to not ready */
+	ppd->driver_link_ready = 0;
+	ppd->offline_disabled_reason = HFI1_ODR_MASK(OPA_LINKDOWN_REASON_NONE);
+
+	/* Skip the tuning for testing (loopback != none) and simulations */
+	if (loopback != LOOPBACK_NONE ||
+	    ppd->dd->icode == ICODE_FUNCTIONAL_SIMULATOR) {
+		ppd->driver_link_ready = 1;
+
+		if (qsfp_mod_present(ppd)) {
+			ret = acquire_chip_resource(ppd->dd,
+						    qsfp_resource(ppd->dd),
+						    QSFP_WAIT);
+			if (ret) {
+				dd_dev_err(ppd->dd, "%s: hfi%d: cannot lock i2c chain\n",
+					   __func__, (int)ppd->dd->hfi1_id);
+				goto bail;
+			}
+
+			refresh_qsfp_cache(ppd, &ppd->qsfp_info);
+			release_chip_resource(ppd->dd, qsfp_resource(ppd->dd));
+		}
+
+		return;
+	}
+
+	switch (ppd->port_type) {
+	case PORT_TYPE_DISCONNECTED:
+		ppd->offline_disabled_reason =
+			HFI1_ODR_MASK(OPA_LINKDOWN_REASON_DISCONNECTED);
+		dd_dev_warn(dd, "%s: Port disconnected, disabling port\n",
+			    __func__);
+		goto bail;
+	case PORT_TYPE_FIXED:
+		/* platform_atten, remote_atten pre-zeroed to catch error */
+		get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_LOCAL_ATTEN_25G, &platform_atten, 4);
+
+		get_platform_config_field(
+			ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+			PORT_TABLE_REMOTE_ATTEN_25G, &remote_atten, 4);
+
+		total_atten = platform_atten + remote_atten;
+
+		tuning_method = OPA_PASSIVE_TUNING;
+		break;
+	case PORT_TYPE_VARIABLE:
+		if (qsfp_mod_present(ppd)) {
+			/*
+			 * platform_atten, remote_atten pre-zeroed to
+			 * catch error
+			 */
+			get_platform_config_field(
+				ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+				PORT_TABLE_LOCAL_ATTEN_25G,
+				&platform_atten, 4);
+
+			get_platform_config_field(
+				ppd->dd, PLATFORM_CONFIG_PORT_TABLE, 0,
+				PORT_TABLE_REMOTE_ATTEN_25G,
+				&remote_atten, 4);
+
+			total_atten = platform_atten + remote_atten;
+
+			tuning_method = OPA_PASSIVE_TUNING;
+		} else {
+			ppd->offline_disabled_reason =
+			     HFI1_ODR_MASK(OPA_LINKDOWN_REASON_CHASSIS_CONFIG);
+			goto bail;
+		}
+		break;
+	case PORT_TYPE_QSFP:
+		if (qsfp_mod_present(ppd)) {
+			ret = acquire_chip_resource(ppd->dd,
+						    qsfp_resource(ppd->dd),
+						    QSFP_WAIT);
+			if (ret) {
+				dd_dev_err(ppd->dd, "%s: hfi%d: cannot lock i2c chain\n",
+					   __func__, (int)ppd->dd->hfi1_id);
+				goto bail;
+			}
+			refresh_qsfp_cache(ppd, &ppd->qsfp_info);
+
+			if (ppd->qsfp_info.cache_valid) {
+				ret = tune_qsfp(ppd,
+						&tx_preset_index,
+						&rx_preset_index,
+						&tuning_method,
+						&total_atten);
+
+				/*
+				 * We may have modified the QSFP memory, so
+				 * update the cache to reflect the changes
+				 */
+				refresh_qsfp_cache(ppd, &ppd->qsfp_info);
+				limiting_active =
+						ppd->qsfp_info.limiting_active;
+			} else {
+				dd_dev_err(dd,
+					   "%s: Reading QSFP memory failed\n",
+					   __func__);
+				ret = -EINVAL; /* a fail indication */
+			}
+			release_chip_resource(ppd->dd, qsfp_resource(ppd->dd));
+			if (ret)
+				goto bail;
+		} else {
+			ppd->offline_disabled_reason =
+			   HFI1_ODR_MASK(
+				OPA_LINKDOWN_REASON_LOCAL_MEDIA_NOT_INSTALLED);
+			goto bail;
+		}
+		break;
+	default:
+		dd_dev_warn(ppd->dd, "%s: Unknown port type\n", __func__);
+		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, limiting_active);
+
+	if (!ret)
+		ppd->driver_link_ready = 1;
+
+	return;
+bail:
+	ppd->driver_link_ready = 0;
+}