Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 531 insertions, 0 deletions

diff --git a/drivers/net/ethernet/sfc/mcdi_mon.c b/drivers/net/ethernet/sfc/mcdi_mon.c
new file mode 100644
index 000000000..f5128db7c
--- /dev/null
+++ b/drivers/net/ethernet/sfc/mcdi_mon.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/****************************************************************************
+ * Driver for Solarflare network controllers and boards
+ * Copyright 2011-2013 Solarflare Communications Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/hwmon.h>
+#include <linux/stat.h>
+
+#include "net_driver.h"
+#include "mcdi.h"
+#include "mcdi_pcol.h"
+#include "nic.h"
+
+enum efx_hwmon_type {
+	EFX_HWMON_UNKNOWN,
+	EFX_HWMON_TEMP,         /* temperature */
+	EFX_HWMON_COOL,         /* cooling device, probably a heatsink */
+	EFX_HWMON_IN,		/* voltage */
+	EFX_HWMON_CURR,		/* current */
+	EFX_HWMON_POWER,	/* power */
+	EFX_HWMON_TYPES_COUNT
+};
+
+static const char *const efx_hwmon_unit[EFX_HWMON_TYPES_COUNT] = {
+	[EFX_HWMON_TEMP]  = " degC",
+	[EFX_HWMON_COOL]  = " rpm", /* though nonsense for a heatsink */
+	[EFX_HWMON_IN]    = " mV",
+	[EFX_HWMON_CURR]  = " mA",
+	[EFX_HWMON_POWER] = " W",
+};
+
+static const struct {
+	const char *label;
+	enum efx_hwmon_type hwmon_type;
+	int port;
+} efx_mcdi_sensor_type[] = {
+#define SENSOR(name, label, hwmon_type, port)				\
+	[MC_CMD_SENSOR_##name] = { label, EFX_HWMON_ ## hwmon_type, port }
+	SENSOR(CONTROLLER_TEMP,		"Controller board temp.",   TEMP,  -1),
+	SENSOR(PHY_COMMON_TEMP,		"PHY temp.",		    TEMP,  -1),
+	SENSOR(CONTROLLER_COOLING,	"Controller heat sink",	    COOL,  -1),
+	SENSOR(PHY0_TEMP,		"PHY temp.",		    TEMP,  0),
+	SENSOR(PHY0_COOLING,		"PHY heat sink",	    COOL,  0),
+	SENSOR(PHY1_TEMP,		"PHY temp.",		    TEMP,  1),
+	SENSOR(PHY1_COOLING,		"PHY heat sink",	    COOL,  1),
+	SENSOR(IN_1V0,			"1.0V supply",		    IN,    -1),
+	SENSOR(IN_1V2,			"1.2V supply",		    IN,    -1),
+	SENSOR(IN_1V8,			"1.8V supply",		    IN,    -1),
+	SENSOR(IN_2V5,			"2.5V supply",		    IN,    -1),
+	SENSOR(IN_3V3,			"3.3V supply",		    IN,    -1),
+	SENSOR(IN_12V0,			"12.0V supply",		    IN,    -1),
+	SENSOR(IN_1V2A,			"1.2V analogue supply",	    IN,    -1),
+	SENSOR(IN_VREF,			"Ref. voltage",		    IN,    -1),
+	SENSOR(OUT_VAOE,		"AOE FPGA supply",	    IN,    -1),
+	SENSOR(AOE_TEMP,		"AOE FPGA temp.",	    TEMP,  -1),
+	SENSOR(PSU_AOE_TEMP,		"AOE regulator temp.",	    TEMP,  -1),
+	SENSOR(PSU_TEMP,		"Controller regulator temp.",
+								    TEMP,  -1),
+	SENSOR(FAN_0,			"Fan 0",		    COOL,  -1),
+	SENSOR(FAN_1,			"Fan 1",		    COOL,  -1),
+	SENSOR(FAN_2,			"Fan 2",		    COOL,  -1),
+	SENSOR(FAN_3,			"Fan 3",		    COOL,  -1),
+	SENSOR(FAN_4,			"Fan 4",		    COOL,  -1),
+	SENSOR(IN_VAOE,			"AOE input supply",	    IN,    -1),
+	SENSOR(OUT_IAOE,		"AOE output current",	    CURR,  -1),
+	SENSOR(IN_IAOE,			"AOE input current",	    CURR,  -1),
+	SENSOR(NIC_POWER,		"Board power use",	    POWER, -1),
+	SENSOR(IN_0V9,			"0.9V supply",		    IN,    -1),
+	SENSOR(IN_I0V9,			"0.9V supply current",	    CURR,  -1),
+	SENSOR(IN_I1V2,			"1.2V supply current",	    CURR,  -1),
+	SENSOR(IN_0V9_ADC,		"0.9V supply (ext. ADC)",   IN,    -1),
+	SENSOR(CONTROLLER_2_TEMP,	"Controller board temp. 2", TEMP,  -1),
+	SENSOR(VREG_INTERNAL_TEMP,	"Regulator die temp.",	    TEMP,  -1),
+	SENSOR(VREG_0V9_TEMP,		"0.9V regulator temp.",     TEMP,  -1),
+	SENSOR(VREG_1V2_TEMP,		"1.2V regulator temp.",     TEMP,  -1),
+	SENSOR(CONTROLLER_VPTAT,
+			      "Controller PTAT voltage (int. ADC)", IN,    -1),
+	SENSOR(CONTROLLER_INTERNAL_TEMP,
+				 "Controller die temp. (int. ADC)", TEMP,  -1),
+	SENSOR(CONTROLLER_VPTAT_EXTADC,
+			      "Controller PTAT voltage (ext. ADC)", IN,    -1),
+	SENSOR(CONTROLLER_INTERNAL_TEMP_EXTADC,
+				 "Controller die temp. (ext. ADC)", TEMP,  -1),
+	SENSOR(AMBIENT_TEMP,		"Ambient temp.",	    TEMP,  -1),
+	SENSOR(AIRFLOW,			"Air flow raw",		    IN,    -1),
+	SENSOR(VDD08D_VSS08D_CSR,	"0.9V die (int. ADC)",	    IN,    -1),
+	SENSOR(VDD08D_VSS08D_CSR_EXTADC, "0.9V die (ext. ADC)",	    IN,    -1),
+	SENSOR(HOTPOINT_TEMP,  "Controller board temp. (hotpoint)", TEMP,  -1),
+#undef SENSOR
+};
+
+static const char *const sensor_status_names[] = {
+	[MC_CMD_SENSOR_STATE_OK] = "OK",
+	[MC_CMD_SENSOR_STATE_WARNING] = "Warning",
+	[MC_CMD_SENSOR_STATE_FATAL] = "Fatal",
+	[MC_CMD_SENSOR_STATE_BROKEN] = "Device failure",
+	[MC_CMD_SENSOR_STATE_NO_READING] = "No reading",
+};
+
+void efx_mcdi_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
+{
+	unsigned int type, state, value;
+	enum efx_hwmon_type hwmon_type = EFX_HWMON_UNKNOWN;
+	const char *name = NULL, *state_txt, *unit;
+
+	type = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_MONITOR);
+	state = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_STATE);
+	value = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_VALUE);
+
+	/* Deal gracefully with the board having more drivers than we
+	 * know about, but do not expect new sensor states. */
+	if (type < ARRAY_SIZE(efx_mcdi_sensor_type)) {
+		name = efx_mcdi_sensor_type[type].label;
+		hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
+	}
+	if (!name)
+		name = "No sensor name available";
+	EFX_WARN_ON_PARANOID(state >= ARRAY_SIZE(sensor_status_names));
+	state_txt = sensor_status_names[state];
+	EFX_WARN_ON_PARANOID(hwmon_type >= EFX_HWMON_TYPES_COUNT);
+	unit = efx_hwmon_unit[hwmon_type];
+	if (!unit)
+		unit = "";
+
+	netif_err(efx, hw, efx->net_dev,
+		  "Sensor %d (%s) reports condition '%s' for value %d%s\n",
+		  type, name, state_txt, value, unit);
+}
+
+#ifdef CONFIG_SFC_MCDI_MON
+
+struct efx_mcdi_mon_attribute {
+	struct device_attribute dev_attr;
+	unsigned int index;
+	unsigned int type;
+	enum efx_hwmon_type hwmon_type;
+	unsigned int limit_value;
+	char name[12];
+};
+
+static int efx_mcdi_mon_update(struct efx_nic *efx)
+{
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_READ_SENSORS_EXT_IN_LEN);
+	int rc;
+
+	MCDI_SET_QWORD(inbuf, READ_SENSORS_EXT_IN_DMA_ADDR,
+		       hwmon->dma_buf.dma_addr);
+	MCDI_SET_DWORD(inbuf, READ_SENSORS_EXT_IN_LENGTH, hwmon->dma_buf.len);
+
+	rc = efx_mcdi_rpc(efx, MC_CMD_READ_SENSORS,
+			  inbuf, sizeof(inbuf), NULL, 0, NULL);
+	if (rc == 0)
+		hwmon->last_update = jiffies;
+	return rc;
+}
+
+static int efx_mcdi_mon_get_entry(struct device *dev, unsigned int index,
+				  efx_dword_t *entry)
+{
+	struct efx_nic *efx = dev_get_drvdata(dev->parent);
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+	int rc;
+
+	BUILD_BUG_ON(MC_CMD_READ_SENSORS_OUT_LEN != 0);
+
+	mutex_lock(&hwmon->update_lock);
+
+	/* Use cached value if last update was < 1 s ago */
+	if (time_before(jiffies, hwmon->last_update + HZ))
+		rc = 0;
+	else
+		rc = efx_mcdi_mon_update(efx);
+
+	/* Copy out the requested entry */
+	*entry = ((efx_dword_t *)hwmon->dma_buf.addr)[index];
+
+	mutex_unlock(&hwmon->update_lock);
+
+	return rc;
+}
+
+static ssize_t efx_mcdi_mon_show_value(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct efx_mcdi_mon_attribute *mon_attr =
+		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
+	efx_dword_t entry;
+	unsigned int value, state;
+	int rc;
+
+	rc = efx_mcdi_mon_get_entry(dev, mon_attr->index, &entry);
+	if (rc)
+		return rc;
+
+	state = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_STATE);
+	if (state == MC_CMD_SENSOR_STATE_NO_READING)
+		return -EBUSY;
+
+	value = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_VALUE);
+
+	switch (mon_attr->hwmon_type) {
+	case EFX_HWMON_TEMP:
+		/* Convert temperature from degrees to milli-degrees Celsius */
+		value *= 1000;
+		break;
+	case EFX_HWMON_POWER:
+		/* Convert power from watts to microwatts */
+		value *= 1000000;
+		break;
+	default:
+		/* No conversion needed */
+		break;
+	}
+
+	return sprintf(buf, "%u\n", value);
+}
+
+static ssize_t efx_mcdi_mon_show_limit(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct efx_mcdi_mon_attribute *mon_attr =
+		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
+	unsigned int value;
+
+	value = mon_attr->limit_value;
+
+	switch (mon_attr->hwmon_type) {
+	case EFX_HWMON_TEMP:
+		/* Convert temperature from degrees to milli-degrees Celsius */
+		value *= 1000;
+		break;
+	case EFX_HWMON_POWER:
+		/* Convert power from watts to microwatts */
+		value *= 1000000;
+		break;
+	default:
+		/* No conversion needed */
+		break;
+	}
+
+	return sprintf(buf, "%u\n", value);
+}
+
+static ssize_t efx_mcdi_mon_show_alarm(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct efx_mcdi_mon_attribute *mon_attr =
+		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
+	efx_dword_t entry;
+	int state;
+	int rc;
+
+	rc = efx_mcdi_mon_get_entry(dev, mon_attr->index, &entry);
+	if (rc)
+		return rc;
+
+	state = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_STATE);
+	return sprintf(buf, "%d\n", state != MC_CMD_SENSOR_STATE_OK);
+}
+
+static ssize_t efx_mcdi_mon_show_label(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct efx_mcdi_mon_attribute *mon_attr =
+		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
+	return sprintf(buf, "%s\n",
+		       efx_mcdi_sensor_type[mon_attr->type].label);
+}
+
+static void
+efx_mcdi_mon_add_attr(struct efx_nic *efx, const char *name,
+		      ssize_t (*reader)(struct device *,
+					struct device_attribute *, char *),
+		      unsigned int index, unsigned int type,
+		      unsigned int limit_value)
+{
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+	struct efx_mcdi_mon_attribute *attr = &hwmon->attrs[hwmon->n_attrs];
+
+	strscpy(attr->name, name, sizeof(attr->name));
+	attr->index = index;
+	attr->type = type;
+	if (type < ARRAY_SIZE(efx_mcdi_sensor_type))
+		attr->hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
+	else
+		attr->hwmon_type = EFX_HWMON_UNKNOWN;
+	attr->limit_value = limit_value;
+	sysfs_attr_init(&attr->dev_attr.attr);
+	attr->dev_attr.attr.name = attr->name;
+	attr->dev_attr.attr.mode = 0444;
+	attr->dev_attr.show = reader;
+	hwmon->group.attrs[hwmon->n_attrs++] = &attr->dev_attr.attr;
+}
+
+int efx_mcdi_mon_probe(struct efx_nic *efx)
+{
+	unsigned int n_temp = 0, n_cool = 0, n_in = 0, n_curr = 0, n_power = 0;
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_SENSOR_INFO_EXT_IN_LEN);
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_SENSOR_INFO_OUT_LENMAX);
+	unsigned int n_pages, n_sensors, n_attrs, page;
+	size_t outlen;
+	char name[12];
+	u32 mask;
+	int rc, i, j, type;
+
+	/* Find out how many sensors are present */
+	n_sensors = 0;
+	page = 0;
+	do {
+		MCDI_SET_DWORD(inbuf, SENSOR_INFO_EXT_IN_PAGE, page);
+
+		rc = efx_mcdi_rpc(efx, MC_CMD_SENSOR_INFO, inbuf, sizeof(inbuf),
+				  outbuf, sizeof(outbuf), &outlen);
+		if (rc)
+			return rc;
+		if (outlen < MC_CMD_SENSOR_INFO_OUT_LENMIN)
+			return -EIO;
+
+		mask = MCDI_DWORD(outbuf, SENSOR_INFO_OUT_MASK);
+		n_sensors += hweight32(mask & ~(1 << MC_CMD_SENSOR_PAGE0_NEXT));
+		++page;
+	} while (mask & (1 << MC_CMD_SENSOR_PAGE0_NEXT));
+	n_pages = page;
+
+	/* Don't create a device if there are none */
+	if (n_sensors == 0)
+		return 0;
+
+	rc = efx_nic_alloc_buffer(
+		efx, &hwmon->dma_buf,
+		n_sensors * MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_LEN,
+		GFP_KERNEL);
+	if (rc)
+		return rc;
+
+	mutex_init(&hwmon->update_lock);
+	efx_mcdi_mon_update(efx);
+
+	/* Allocate space for the maximum possible number of
+	 * attributes for this set of sensors:
+	 * value, min, max, crit, alarm and label for each sensor.
+	 */
+	n_attrs = 6 * n_sensors;
+	hwmon->attrs = kcalloc(n_attrs, sizeof(*hwmon->attrs), GFP_KERNEL);
+	if (!hwmon->attrs) {
+		rc = -ENOMEM;
+		goto fail;
+	}
+	hwmon->group.attrs = kcalloc(n_attrs + 1, sizeof(struct attribute *),
+				     GFP_KERNEL);
+	if (!hwmon->group.attrs) {
+		rc = -ENOMEM;
+		goto fail;
+	}
+
+	for (i = 0, j = -1, type = -1; ; i++) {
+		enum efx_hwmon_type hwmon_type;
+		const char *hwmon_prefix;
+		unsigned hwmon_index;
+		u16 min1, max1, min2, max2;
+
+		/* Find next sensor type or exit if there is none */
+		do {
+			type++;
+
+			if ((type % 32) == 0) {
+				page = type / 32;
+				j = -1;
+				if (page == n_pages)
+					goto hwmon_register;
+
+				MCDI_SET_DWORD(inbuf, SENSOR_INFO_EXT_IN_PAGE,
+					       page);
+				rc = efx_mcdi_rpc(efx, MC_CMD_SENSOR_INFO,
+						  inbuf, sizeof(inbuf),
+						  outbuf, sizeof(outbuf),
+						  &outlen);
+				if (rc)
+					goto fail;
+				if (outlen < MC_CMD_SENSOR_INFO_OUT_LENMIN) {
+					rc = -EIO;
+					goto fail;
+				}
+
+				mask = (MCDI_DWORD(outbuf,
+						   SENSOR_INFO_OUT_MASK) &
+					~(1 << MC_CMD_SENSOR_PAGE0_NEXT));
+
+				/* Check again for short response */
+				if (outlen <
+				    MC_CMD_SENSOR_INFO_OUT_LEN(hweight32(mask))) {
+					rc = -EIO;
+					goto fail;
+				}
+			}
+		} while (!(mask & (1 << type % 32)));
+		j++;
+
+		if (type < ARRAY_SIZE(efx_mcdi_sensor_type)) {
+			hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
+
+			/* Skip sensors specific to a different port */
+			if (hwmon_type != EFX_HWMON_UNKNOWN &&
+			    efx_mcdi_sensor_type[type].port >= 0 &&
+			    efx_mcdi_sensor_type[type].port !=
+			    efx_port_num(efx))
+				continue;
+		} else {
+			hwmon_type = EFX_HWMON_UNKNOWN;
+		}
+
+		switch (hwmon_type) {
+		case EFX_HWMON_TEMP:
+			hwmon_prefix = "temp";
+			hwmon_index = ++n_temp; /* 1-based */
+			break;
+		case EFX_HWMON_COOL:
+			/* This is likely to be a heatsink, but there
+			 * is no convention for representing cooling
+			 * devices other than fans.
+			 */
+			hwmon_prefix = "fan";
+			hwmon_index = ++n_cool; /* 1-based */
+			break;
+		default:
+			hwmon_prefix = "in";
+			hwmon_index = n_in++; /* 0-based */
+			break;
+		case EFX_HWMON_CURR:
+			hwmon_prefix = "curr";
+			hwmon_index = ++n_curr; /* 1-based */
+			break;
+		case EFX_HWMON_POWER:
+			hwmon_prefix = "power";
+			hwmon_index = ++n_power; /* 1-based */
+			break;
+		}
+
+		min1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, j, MIN1);
+		max1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, j, MAX1);
+		min2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, j, MIN2);
+		max2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, j, MAX2);
+
+		if (min1 != max1) {
+			snprintf(name, sizeof(name), "%s%u_input",
+				 hwmon_prefix, hwmon_index);
+			efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_value, i, type, 0);
+
+			if (hwmon_type != EFX_HWMON_POWER) {
+				snprintf(name, sizeof(name), "%s%u_min",
+					 hwmon_prefix, hwmon_index);
+				efx_mcdi_mon_add_attr(
+					efx, name, efx_mcdi_mon_show_limit,
+					i, type, min1);
+			}
+
+			snprintf(name, sizeof(name), "%s%u_max",
+				 hwmon_prefix, hwmon_index);
+			efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_limit,
+				i, type, max1);
+
+			if (min2 != max2) {
+				/* Assume max2 is critical value.
+				 * But we have no good way to expose min2.
+				 */
+				snprintf(name, sizeof(name), "%s%u_crit",
+					 hwmon_prefix, hwmon_index);
+				efx_mcdi_mon_add_attr(
+					efx, name, efx_mcdi_mon_show_limit,
+					i, type, max2);
+			}
+		}
+
+		snprintf(name, sizeof(name), "%s%u_alarm",
+			 hwmon_prefix, hwmon_index);
+		efx_mcdi_mon_add_attr(
+			efx, name, efx_mcdi_mon_show_alarm, i, type, 0);
+
+		if (type < ARRAY_SIZE(efx_mcdi_sensor_type) &&
+		    efx_mcdi_sensor_type[type].label) {
+			snprintf(name, sizeof(name), "%s%u_label",
+				 hwmon_prefix, hwmon_index);
+			efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_label, i, type, 0);
+		}
+	}
+
+hwmon_register:
+	hwmon->groups[0] = &hwmon->group;
+	hwmon->device = hwmon_device_register_with_groups(&efx->pci_dev->dev,
+							  KBUILD_MODNAME, NULL,
+							  hwmon->groups);
+	if (IS_ERR(hwmon->device)) {
+		rc = PTR_ERR(hwmon->device);
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	efx_mcdi_mon_remove(efx);
+	return rc;
+}
+
+void efx_mcdi_mon_remove(struct efx_nic *efx)
+{
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+
+	if (hwmon->device)
+		hwmon_device_unregister(hwmon->device);
+	kfree(hwmon->attrs);
+	kfree(hwmon->group.attrs);
+	efx_nic_free_buffer(efx, &hwmon->dma_buf);
+}
+
+#endif /* CONFIG_SFC_MCDI_MON */