Merge branch 'pci/enumeration'

  - add decoding for 16 GT/s link speed (Jay Fang)

  - add interfaces to get max link speed and width (Tal Gilboa)

  - add pcie_bandwidth_capable() to compute max supported link bandwidth
    (Tal Gilboa)

  - add pcie_bandwidth_available() to compute bandwidth available to device
    (Tal Gilboa)

  - add pcie_print_link_status() to log link speed and whether it's limited
    (Tal Gilboa)

  - use PCI core interfaces to report when device performance may be
    limited by its slot instead of doing it in each driver (Tal Gilboa)

* pci/enumeration:
  fm10k: Report PCIe link properties with pcie_print_link_status()
  net/mlx5e: Use pcie_bandwidth_available() to compute bandwidth
  net/mlx5: Report PCIe link properties with pcie_print_link_status()
  net/mlx4_core: Report PCIe link properties with pcie_print_link_status()
  PCI: Add pcie_print_link_status() to log link speed and whether it's limited
  PCI: Add pcie_bandwidth_available() to compute bandwidth available to device
  PCI: Add pcie_bandwidth_capable() to compute max supported link bandwidth
  PCI: Add pcie_get_width_cap() to find max supported link width
  PCI: Add pcie_get_speed_cap() to find max supported link speed
  PCI: Add decoding for 16 GT/s link speed

11 files changed, 221 insertions, 231 deletions

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
index a434fecfdfeb..aa05fb534942 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
@@ -2120,91 +2120,6 @@ static int fm10k_sw_init(struct fm10k_intfc *interface,
 	return 0;
 }
 
-static void fm10k_slot_warn(struct fm10k_intfc *interface)
-{
-	enum pcie_link_width width = PCIE_LNK_WIDTH_UNKNOWN;
-	enum pci_bus_speed speed = PCI_SPEED_UNKNOWN;
-	struct fm10k_hw *hw = &interface->hw;
-	int max_gts = 0, expected_gts = 0;
-
-	if (pcie_get_minimum_link(interface->pdev, &speed, &width) ||
-	    speed == PCI_SPEED_UNKNOWN || width == PCIE_LNK_WIDTH_UNKNOWN) {
-		dev_warn(&interface->pdev->dev,
-			 "Unable to determine PCI Express bandwidth.\n");
-		return;
-	}
-
-	switch (speed) {
-	case PCIE_SPEED_2_5GT:
-		/* 8b/10b encoding reduces max throughput by 20% */
-		max_gts = 2 * width;
-		break;
-	case PCIE_SPEED_5_0GT:
-		/* 8b/10b encoding reduces max throughput by 20% */
-		max_gts = 4 * width;
-		break;
-	case PCIE_SPEED_8_0GT:
-		/* 128b/130b encoding has less than 2% impact on throughput */
-		max_gts = 8 * width;
-		break;
-	default:
-		dev_warn(&interface->pdev->dev,
-			 "Unable to determine PCI Express bandwidth.\n");
-		return;
-	}
-
-	dev_info(&interface->pdev->dev,
-		 "PCI Express bandwidth of %dGT/s available\n",
-		 max_gts);
-	dev_info(&interface->pdev->dev,
-		 "(Speed:%s, Width: x%d, Encoding Loss:%s, Payload:%s)\n",
-		 (speed == PCIE_SPEED_8_0GT ? "8.0GT/s" :
-		  speed == PCIE_SPEED_5_0GT ? "5.0GT/s" :
-		  speed == PCIE_SPEED_2_5GT ? "2.5GT/s" :
-		  "Unknown"),
-		 hw->bus.width,
-		 (speed == PCIE_SPEED_2_5GT ? "20%" :
-		  speed == PCIE_SPEED_5_0GT ? "20%" :
-		  speed == PCIE_SPEED_8_0GT ? "<2%" :
-		  "Unknown"),
-		 (hw->bus.payload == fm10k_bus_payload_128 ? "128B" :
-		  hw->bus.payload == fm10k_bus_payload_256 ? "256B" :
-		  hw->bus.payload == fm10k_bus_payload_512 ? "512B" :
-		  "Unknown"));
-
-	switch (hw->bus_caps.speed) {
-	case fm10k_bus_speed_2500:
-		/* 8b/10b encoding reduces max throughput by 20% */
-		expected_gts = 2 * hw->bus_caps.width;
-		break;
-	case fm10k_bus_speed_5000:
-		/* 8b/10b encoding reduces max throughput by 20% */
-		expected_gts = 4 * hw->bus_caps.width;
-		break;
-	case fm10k_bus_speed_8000:
-		/* 128b/130b encoding has less than 2% impact on throughput */
-		expected_gts = 8 * hw->bus_caps.width;
-		break;
-	default:
-		dev_warn(&interface->pdev->dev,
-			 "Unable to determine expected PCI Express bandwidth.\n");
-		return;
-	}
-
-	if (max_gts >= expected_gts)
-		return;
-
-	dev_warn(&interface->pdev->dev,
-		 "This device requires %dGT/s of bandwidth for optimal performance.\n",
-		 expected_gts);
-	dev_warn(&interface->pdev->dev,
-		 "A %sslot with x%d lanes is suggested.\n",
-		 (hw->bus_caps.speed == fm10k_bus_speed_2500 ? "2.5GT/s " :
-		  hw->bus_caps.speed == fm10k_bus_speed_5000 ? "5.0GT/s " :
-		  hw->bus_caps.speed == fm10k_bus_speed_8000 ? "8.0GT/s " : ""),
-		 hw->bus_caps.width);
-}
-
 /**
  * fm10k_probe - Device Initialization Routine
  * @pdev: PCI device information struct
@@ -2326,7 +2241,7 @@ static int fm10k_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	mod_timer(&interface->service_timer, (HZ * 2) + jiffies);
 
 	/* print warning for non-optimal configurations */
-	fm10k_slot_warn(interface);
+	pcie_print_link_status(interface->pdev);
 
 	/* report MAC address for logging */
 	dev_info(&pdev->dev, "%pM\n", netdev->dev_addr);
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 4d84cab77105..30cacac54e69 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -623,85 +623,6 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 	return 0;
 }
 
-static int mlx4_get_pcie_dev_link_caps(struct mlx4_dev *dev,
-				       enum pci_bus_speed *speed,
-				       enum pcie_link_width *width)
-{
-	u32 lnkcap1, lnkcap2;
-	int err1, err2;
-
-#define  PCIE_MLW_CAP_SHIFT 4	/* start of MLW mask in link capabilities */
-
-	*speed = PCI_SPEED_UNKNOWN;
-	*width = PCIE_LNK_WIDTH_UNKNOWN;
-
-	err1 = pcie_capability_read_dword(dev->persist->pdev, PCI_EXP_LNKCAP,
-					  &lnkcap1);
-	err2 = pcie_capability_read_dword(dev->persist->pdev, PCI_EXP_LNKCAP2,
-					  &lnkcap2);
-	if (!err2 && lnkcap2) { /* PCIe r3.0-compliant */
-		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
-			*speed = PCIE_SPEED_8_0GT;
-		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
-			*speed = PCIE_SPEED_5_0GT;
-		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
-			*speed = PCIE_SPEED_2_5GT;
-	}
-	if (!err1) {
-		*width = (lnkcap1 & PCI_EXP_LNKCAP_MLW) >> PCIE_MLW_CAP_SHIFT;
-		if (!lnkcap2) { /* pre-r3.0 */
-			if (lnkcap1 & PCI_EXP_LNKCAP_SLS_5_0GB)
-				*speed = PCIE_SPEED_5_0GT;
-			else if (lnkcap1 & PCI_EXP_LNKCAP_SLS_2_5GB)
-				*speed = PCIE_SPEED_2_5GT;
-		}
-	}
-
-	if (*speed == PCI_SPEED_UNKNOWN || *width == PCIE_LNK_WIDTH_UNKNOWN) {
-		return err1 ? err1 :
-			err2 ? err2 : -EINVAL;
-	}
-	return 0;
-}
-
-static void mlx4_check_pcie_caps(struct mlx4_dev *dev)
-{
-	enum pcie_link_width width, width_cap;
-	enum pci_bus_speed speed, speed_cap;
-	int err;
-
-#define PCIE_SPEED_STR(speed) \
-	(speed == PCIE_SPEED_8_0GT ? "8.0GT/s" : \
-	 speed == PCIE_SPEED_5_0GT ? "5.0GT/s" : \
-	 speed == PCIE_SPEED_2_5GT ? "2.5GT/s" : \
-	 "Unknown")
-
-	err = mlx4_get_pcie_dev_link_caps(dev, &speed_cap, &width_cap);
-	if (err) {
-		mlx4_warn(dev,
-			  "Unable to determine PCIe device BW capabilities\n");
-		return;
-	}
-
-	err = pcie_get_minimum_link(dev->persist->pdev, &speed, &width);
-	if (err || speed == PCI_SPEED_UNKNOWN ||
-	    width == PCIE_LNK_WIDTH_UNKNOWN) {
-		mlx4_warn(dev,
-			  "Unable to determine PCI device chain minimum BW\n");
-		return;
-	}
-
-	if (width != width_cap || speed != speed_cap)
-		mlx4_warn(dev,
-			  "PCIe BW is different than device's capability\n");
-
-	mlx4_info(dev, "PCIe link speed is %s, device supports %s\n",
-		  PCIE_SPEED_STR(speed), PCIE_SPEED_STR(speed_cap));
-	mlx4_info(dev, "PCIe link width is x%d, device supports x%d\n",
-		  width, width_cap);
-	return;
-}
-
 /*The function checks if there are live vf, return the num of them*/
 static int mlx4_how_many_lives_vf(struct mlx4_dev *dev)
 {
@@ -3475,7 +3396,7 @@ slave_start:
 	 * express device capabilities are under-satisfied by the bus.
 	 */
 	if (!mlx4_is_slave(dev))
-		mlx4_check_pcie_caps(dev);
+		pcie_print_link_status(dev->persist->pdev);
 
 	/* In master functions, the communication channel must be initialized
 	 * after obtaining its address from fw */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 47bab842c5ee..93291ec4a3d1 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3864,36 +3864,6 @@ void mlx5e_build_default_indir_rqt(u32 *indirection_rqt, int len,
 		indirection_rqt[i] = i % num_channels;
 }
 
-static int mlx5e_get_pci_bw(struct mlx5_core_dev *mdev, u32 *pci_bw)
-{
-	enum pcie_link_width width;
-	enum pci_bus_speed speed;
-	int err = 0;
-
-	err = pcie_get_minimum_link(mdev->pdev, &speed, &width);
-	if (err)
-		return err;
-
-	if (speed == PCI_SPEED_UNKNOWN || width == PCIE_LNK_WIDTH_UNKNOWN)
-		return -EINVAL;
-
-	switch (speed) {
-	case PCIE_SPEED_2_5GT:
-		*pci_bw = 2500 * width;
-		break;
-	case PCIE_SPEED_5_0GT:
-		*pci_bw = 5000 * width;
-		break;
-	case PCIE_SPEED_8_0GT:
-		*pci_bw = 8000 * width;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
 static bool cqe_compress_heuristic(u32 link_speed, u32 pci_bw)
 {
 	return (link_speed && pci_bw &&
@@ -3979,7 +3949,7 @@ void mlx5e_build_nic_params(struct mlx5_core_dev *mdev,
 	params->num_tc       = 1;
 
 	mlx5e_get_max_linkspeed(mdev, &link_speed);
-	mlx5e_get_pci_bw(mdev, &pci_bw);
+	pci_bw = pcie_bandwidth_available(mdev->pdev, NULL, NULL, NULL);
 	mlx5_core_dbg(mdev, "Max link speed = %d, PCI BW = %d\n",
 		      link_speed, pci_bw);
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index 2ef641c91c26..622f02d34aae 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -1043,6 +1043,10 @@ static int mlx5_load_one(struct mlx5_core_dev *dev, struct mlx5_priv *priv,
 	dev_info(&pdev->dev, "firmware version: %d.%d.%d\n", fw_rev_maj(dev),
 		 fw_rev_min(dev), fw_rev_sub(dev));
 
+	/* Only PFs hold the relevant PCIe information for this query */
+	if (mlx5_core_is_pf(dev))
+		pcie_print_link_status(dev->pdev);
+
 	/* on load removing any previous indication of internal error, device is
 	 * up
 	 */
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index eb6bee8724cc..63d0952684fb 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -158,45 +158,18 @@ static DEVICE_ATTR_RO(resource);
 static ssize_t max_link_speed_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	struct pci_dev *pci_dev = to_pci_dev(dev);
-	u32 linkcap;
-	int err;
-	const char *speed;
-
-	err = pcie_capability_read_dword(pci_dev, PCI_EXP_LNKCAP, &linkcap);
-	if (err)
-		return -EINVAL;
-
-	switch (linkcap & PCI_EXP_LNKCAP_SLS) {
-	case PCI_EXP_LNKCAP_SLS_8_0GB:
-		speed = "8 GT/s";
-		break;
-	case PCI_EXP_LNKCAP_SLS_5_0GB:
-		speed = "5 GT/s";
-		break;
-	case PCI_EXP_LNKCAP_SLS_2_5GB:
-		speed = "2.5 GT/s";
-		break;
-	default:
-		speed = "Unknown speed";
-	}
+	struct pci_dev *pdev = to_pci_dev(dev);
 
-	return sprintf(buf, "%s\n", speed);
+	return sprintf(buf, "%s\n", PCIE_SPEED2STR(pcie_get_speed_cap(pdev)));
 }
 static DEVICE_ATTR_RO(max_link_speed);
 
 static ssize_t max_link_width_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	struct pci_dev *pci_dev = to_pci_dev(dev);
-	u32 linkcap;
-	int err;
-
-	err = pcie_capability_read_dword(pci_dev, PCI_EXP_LNKCAP, &linkcap);
-	if (err)
-		return -EINVAL;
+	struct pci_dev *pdev = to_pci_dev(dev);
 
-	return sprintf(buf, "%u\n", (linkcap & PCI_EXP_LNKCAP_MLW) >> 4);
+	return sprintf(buf, "%u\n", pcie_get_width_cap(pdev));
 }
 static DEVICE_ATTR_RO(max_link_width);
 
@@ -213,6 +186,9 @@ static ssize_t current_link_speed_show(struct device *dev,
 		return -EINVAL;
 
 	switch (linkstat & PCI_EXP_LNKSTA_CLS) {
+	case PCI_EXP_LNKSTA_CLS_16_0GB:
+		speed = "16 GT/s";
+		break;
 	case PCI_EXP_LNKSTA_CLS_8_0GB:
 		speed = "8 GT/s";
 		break;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index f6a4dd10d9b0..e7a3917ed389 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5147,6 +5147,180 @@ int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
 EXPORT_SYMBOL(pcie_get_minimum_link);
 
 /**
+ * pcie_bandwidth_available - determine minimum link settings of a PCIe
+ *			      device and its bandwidth limitation
+ * @dev: PCI device to query
+ * @limiting_dev: storage for device causing the bandwidth limitation
+ * @speed: storage for speed of limiting device
+ * @width: storage for width of limiting device
+ *
+ * Walk up the PCI device chain and find the point where the minimum
+ * bandwidth is available.  Return the bandwidth available there and (if
+ * limiting_dev, speed, and width pointers are supplied) information about
+ * that point.  The bandwidth returned is in Mb/s, i.e., megabits/second of
+ * raw bandwidth.
+ */
+u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
+			     enum pci_bus_speed *speed,
+			     enum pcie_link_width *width)
+{
+	u16 lnksta;
+	enum pci_bus_speed next_speed;
+	enum pcie_link_width next_width;
+	u32 bw, next_bw;
+
+	if (speed)
+		*speed = PCI_SPEED_UNKNOWN;
+	if (width)
+		*width = PCIE_LNK_WIDTH_UNKNOWN;
+
+	bw = 0;
+
+	while (dev) {
+		pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
+
+		next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
+		next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
+			PCI_EXP_LNKSTA_NLW_SHIFT;
+
+		next_bw = next_width * PCIE_SPEED2MBS_ENC(next_speed);
+
+		/* Check if current device limits the total bandwidth */
+		if (!bw || next_bw <= bw) {
+			bw = next_bw;
+
+			if (limiting_dev)
+				*limiting_dev = dev;
+			if (speed)
+				*speed = next_speed;
+			if (width)
+				*width = next_width;
+		}
+
+		dev = pci_upstream_bridge(dev);
+	}
+
+	return bw;
+}
+EXPORT_SYMBOL(pcie_bandwidth_available);
+
+/**
+ * pcie_get_speed_cap - query for the PCI device's link speed capability
+ * @dev: PCI device to query
+ *
+ * Query the PCI device speed capability.  Return the maximum link speed
+ * supported by the device.
+ */
+enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev)
+{
+	u32 lnkcap2, lnkcap;
+
+	/*
+	 * PCIe r4.0 sec 7.5.3.18 recommends using the Supported Link
+	 * Speeds Vector in Link Capabilities 2 when supported, falling
+	 * back to Max Link Speed in Link Capabilities otherwise.
+	 */
+	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);
+	if (lnkcap2) { /* PCIe r3.0-compliant */
+		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
+			return PCIE_SPEED_16_0GT;
+		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
+			return PCIE_SPEED_8_0GT;
+		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
+			return PCIE_SPEED_5_0GT;
+		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
+			return PCIE_SPEED_2_5GT;
+		return PCI_SPEED_UNKNOWN;
+	}
+
+	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
+	if (lnkcap) {
+		if (lnkcap & PCI_EXP_LNKCAP_SLS_16_0GB)
+			return PCIE_SPEED_16_0GT;
+		else if (lnkcap & PCI_EXP_LNKCAP_SLS_8_0GB)
+			return PCIE_SPEED_8_0GT;
+		else if (lnkcap & PCI_EXP_LNKCAP_SLS_5_0GB)
+			return PCIE_SPEED_5_0GT;
+		else if (lnkcap & PCI_EXP_LNKCAP_SLS_2_5GB)
+			return PCIE_SPEED_2_5GT;
+	}
+
+	return PCI_SPEED_UNKNOWN;
+}
+
+/**
+ * pcie_get_width_cap - query for the PCI device's link width capability
+ * @dev: PCI device to query
+ *
+ * Query the PCI device width capability.  Return the maximum link width
+ * supported by the device.
+ */
+enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev)
+{
+	u32 lnkcap;
+
+	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
+	if (lnkcap)
+		return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4;
+
+	return PCIE_LNK_WIDTH_UNKNOWN;
+}
+
+/**
+ * pcie_bandwidth_capable - calculate a PCI device's link bandwidth capability
+ * @dev: PCI device
+ * @speed: storage for link speed
+ * @width: storage for link width
+ *
+ * Calculate a PCI device's link bandwidth by querying for its link speed
+ * and width, multiplying them, and applying encoding overhead.  The result
+ * is in Mb/s, i.e., megabits/second of raw bandwidth.
+ */
+u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
+			   enum pcie_link_width *width)
+{
+	*speed = pcie_get_speed_cap(dev);
+	*width = pcie_get_width_cap(dev);
+
+	if (*speed == PCI_SPEED_UNKNOWN || *width == PCIE_LNK_WIDTH_UNKNOWN)
+		return 0;
+
+	return *width * PCIE_SPEED2MBS_ENC(*speed);
+}
+
+/**
+ * pcie_print_link_status - Report the PCI device's link speed and width
+ * @dev: PCI device to query
+ *
+ * Report the available bandwidth at the device.  If this is less than the
+ * device is capable of, report the device's maximum possible bandwidth and
+ * the upstream link that limits its performance to less than that.
+ */
+void pcie_print_link_status(struct pci_dev *dev)
+{
+	enum pcie_link_width width, width_cap;
+	enum pci_bus_speed speed, speed_cap;
+	struct pci_dev *limiting_dev = NULL;
+	u32 bw_avail, bw_cap;
+
+	bw_cap = pcie_bandwidth_capable(dev, &speed_cap, &width_cap);
+	bw_avail = pcie_bandwidth_available(dev, &limiting_dev, &speed, &width);
+
+	if (bw_avail >= bw_cap)
+		pci_info(dev, "%u.%03u Gb/s available bandwidth (%s x%d link)\n",
+			 bw_cap / 1000, bw_cap % 1000,
+			 PCIE_SPEED2STR(speed_cap), width_cap);
+	else
+		pci_info(dev, "%u.%03u Gb/s available bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)\n",
+			 bw_avail / 1000, bw_avail % 1000,
+			 PCIE_SPEED2STR(speed), width,
+			 limiting_dev ? pci_name(limiting_dev) : "<unknown>",
+			 bw_cap / 1000, bw_cap % 1000,
+			 PCIE_SPEED2STR(speed_cap), width_cap);
+}
+EXPORT_SYMBOL(pcie_print_link_status);
+
+/**
  * pci_select_bars - Make BAR mask from the type of resource
  * @dev: the PCI device for which BAR mask is made
  * @flags: resource type mask to be selected
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index fcd81911b127..ce9adec6c66e 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -253,6 +253,27 @@ bool pci_bus_clip_resource(struct pci_dev *dev, int idx);
 void pci_reassigndev_resource_alignment(struct pci_dev *dev);
 void pci_disable_bridge_window(struct pci_dev *dev);
 
+/* PCIe link information */
+#define PCIE_SPEED2STR(speed) \
+	((speed) == PCIE_SPEED_16_0GT ? "16 GT/s" : \
+	 (speed) == PCIE_SPEED_8_0GT ? "8 GT/s" : \
+	 (speed) == PCIE_SPEED_5_0GT ? "5 GT/s" : \
+	 (speed) == PCIE_SPEED_2_5GT ? "2.5 GT/s" : \
+	 "Unknown speed")
+
+/* PCIe speed to Mb/s reduced by encoding overhead */
+#define PCIE_SPEED2MBS_ENC(speed) \
+	((speed) == PCIE_SPEED_16_0GT ? 16000*128/130 : \
+	 (speed) == PCIE_SPEED_8_0GT  ?  8000*128/130 : \
+	 (speed) == PCIE_SPEED_5_0GT  ?  5000*8/10 : \
+	 (speed) == PCIE_SPEED_2_5GT  ?  2500*8/10 : \
+	 0)
+
+enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev);
+enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev);
+u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
+			   enum pcie_link_width *width);
+
 /* Single Root I/O Virtualization */
 struct pci_sriov {
 	int		pos;		/* Capability position */
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ef5377438a1e..86bf045f3d59 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -592,7 +592,7 @@ const unsigned char pcie_link_speed[] = {
 	PCIE_SPEED_2_5GT,		/* 1 */
 	PCIE_SPEED_5_0GT,		/* 2 */
 	PCIE_SPEED_8_0GT,		/* 3 */
-	PCI_SPEED_UNKNOWN,		/* 4 */
+	PCIE_SPEED_16_0GT,		/* 4 */
 	PCI_SPEED_UNKNOWN,		/* 5 */
 	PCI_SPEED_UNKNOWN,		/* 6 */
 	PCI_SPEED_UNKNOWN,		/* 7 */
diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
index d10f556dc03e..191893e19d5c 100644
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -76,6 +76,7 @@ static const char *pci_bus_speed_strings[] = {
 	"2.5 GT/s PCIe",	/* 0x14 */
 	"5.0 GT/s PCIe",	/* 0x15 */
 	"8.0 GT/s PCIe",	/* 0x16 */
+	"16.0 GT/s PCIe",	/* 0x17 */
 };
 
 static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 24e15510a946..926a8cb5d6d4 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -256,6 +256,7 @@ enum pci_bus_speed {
 	PCIE_SPEED_2_5GT		= 0x14,
 	PCIE_SPEED_5_0GT		= 0x15,
 	PCIE_SPEED_8_0GT		= 0x16,
+	PCIE_SPEED_16_0GT		= 0x17,
 	PCI_SPEED_UNKNOWN		= 0xff,
 };
 
@@ -1077,6 +1078,10 @@ int pcie_get_mps(struct pci_dev *dev);
 int pcie_set_mps(struct pci_dev *dev, int mps);
 int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
 			  enum pcie_link_width *width);
+u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
+			     enum pci_bus_speed *speed,
+			     enum pcie_link_width *width);
+void pcie_print_link_status(struct pci_dev *dev);
 void pcie_flr(struct pci_dev *dev);
 int __pci_reset_function_locked(struct pci_dev *dev);
 int pci_reset_function(struct pci_dev *dev);
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 0c79eac5e9b8..103ba797a8f3 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -520,6 +520,7 @@
 #define  PCI_EXP_LNKCAP_SLS_2_5GB 0x00000001 /* LNKCAP2 SLS Vector bit 0 */
 #define  PCI_EXP_LNKCAP_SLS_5_0GB 0x00000002 /* LNKCAP2 SLS Vector bit 1 */
 #define  PCI_EXP_LNKCAP_SLS_8_0GB 0x00000003 /* LNKCAP2 SLS Vector bit 2 */
+#define  PCI_EXP_LNKCAP_SLS_16_0GB 0x00000004 /* LNKCAP2 SLS Vector bit 3 */
 #define  PCI_EXP_LNKCAP_MLW	0x000003f0 /* Maximum Link Width */
 #define  PCI_EXP_LNKCAP_ASPMS	0x00000c00 /* ASPM Support */
 #define  PCI_EXP_LNKCAP_L0SEL	0x00007000 /* L0s Exit Latency */
@@ -547,6 +548,7 @@
 #define  PCI_EXP_LNKSTA_CLS_2_5GB 0x0001 /* Current Link Speed 2.5GT/s */
 #define  PCI_EXP_LNKSTA_CLS_5_0GB 0x0002 /* Current Link Speed 5.0GT/s */
 #define  PCI_EXP_LNKSTA_CLS_8_0GB 0x0003 /* Current Link Speed 8.0GT/s */
+#define  PCI_EXP_LNKSTA_CLS_16_0GB 0x0004 /* Current Link Speed 16.0GT/s */
 #define  PCI_EXP_LNKSTA_NLW	0x03f0	/* Negotiated Link Width */
 #define  PCI_EXP_LNKSTA_NLW_X1	0x0010	/* Current Link Width x1 */
 #define  PCI_EXP_LNKSTA_NLW_X2	0x0020	/* Current Link Width x2 */
@@ -648,8 +650,9 @@
 #define PCI_CAP_EXP_RC_ENDPOINT_SIZEOF_V2	44	/* v2 endpoints without link end here */
 #define PCI_EXP_LNKCAP2		44	/* Link Capabilities 2 */
 #define  PCI_EXP_LNKCAP2_SLS_2_5GB	0x00000002 /* Supported Speed 2.5GT/s */
-#define  PCI_EXP_LNKCAP2_SLS_5_0GB	0x00000004 /* Supported Speed 5.0GT/s */
-#define  PCI_EXP_LNKCAP2_SLS_8_0GB	0x00000008 /* Supported Speed 8.0GT/s */
+#define  PCI_EXP_LNKCAP2_SLS_5_0GB	0x00000004 /* Supported Speed 5GT/s */
+#define  PCI_EXP_LNKCAP2_SLS_8_0GB	0x00000008 /* Supported Speed 8GT/s */
+#define  PCI_EXP_LNKCAP2_SLS_16_0GB	0x00000010 /* Supported Speed 16GT/s */
 #define  PCI_EXP_LNKCAP2_CROSSLINK	0x00000100 /* Crosslink supported */
 #define PCI_EXP_LNKCTL2		48	/* Link Control 2 */
 #define PCI_EXP_LNKSTA2		50	/* Link Status 2 */