sfc: Add hwmon driver for boards using SFC9000-family controllers

The SFC9000-family controllers have firmware to manage all board
peripherals including temperature, heat sink continuity and voltage
sensors.  The firmware reports sensor alarms, which we log, and
will shut down the board if necessary.

Some users may want to monitor their boards more closely, so add an
hwmon driver that exposes all sensors reported by the firmware.  Move
efx_mcdi_sensor_event() into the new file so it can share the array of
sensor labels with the hwmon driver.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

1 files changed, 415 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 000000000000..8a72c10b9a6c
--- /dev/null
+++ b/drivers/net/ethernet/sfc/mcdi_mon.c
@@ -0,0 +1,415 @@
+/****************************************************************************
+ * Driver for Solarflare Solarstorm network controllers and boards
+ * Copyright 2011 Solarflare Communications Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#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            /* input voltage */
+};
+
+static const struct {
+	const char *label;
+	enum efx_hwmon_type hwmon_type;
+	int port;
+} efx_mcdi_sensor_type[MC_CMD_SENSOR_ENTRY_MAXNUM] = {
+#define SENSOR(name, label, hwmon_type, port)			\
+	[MC_CMD_SENSOR_##name] = { label, hwmon_type, port }
+	SENSOR(CONTROLLER_TEMP,	   "Controller temp.",	   EFX_HWMON_TEMP, -1),
+	SENSOR(PHY_COMMON_TEMP,	   "PHY temp.",		   EFX_HWMON_TEMP, -1),
+	SENSOR(CONTROLLER_COOLING, "Controller cooling",   EFX_HWMON_COOL, -1),
+	SENSOR(PHY0_TEMP,	   "PHY temp.",		   EFX_HWMON_TEMP, 0),
+	SENSOR(PHY0_COOLING,	   "PHY cooling",	   EFX_HWMON_COOL, 0),
+	SENSOR(PHY1_TEMP,	   "PHY temp.",		   EFX_HWMON_TEMP, 1),
+	SENSOR(PHY1_COOLING, 	   "PHY cooling",	   EFX_HWMON_COOL, 1),
+	SENSOR(IN_1V0,		   "1.0V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_1V2,		   "1.2V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_1V8,		   "1.8V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_2V5,		   "2.5V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_3V3,		   "3.3V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_12V0,		   "12.0V supply",	   EFX_HWMON_IN,   -1),
+	SENSOR(IN_1V2A,		   "1.2V analogue supply", EFX_HWMON_IN,   -1),
+	SENSOR(IN_VREF,		   "ref. voltage",	   EFX_HWMON_IN,   -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",
+};
+
+void efx_mcdi_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
+{
+	unsigned int type, state, value;
+	const char *name = NULL, *state_txt;
+
+	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;
+	if (!name)
+		name = "No sensor name available";
+	EFX_BUG_ON_PARANOID(state >= ARRAY_SIZE(sensor_status_names));
+	state_txt = sensor_status_names[state];
+
+	netif_err(efx, hw, efx->net_dev,
+		  "Sensor %d (%s) reports condition '%s' for raw value %d\n",
+		  type, name, state_txt, value);
+}
+
+#ifdef CONFIG_SFC_MCDI_MON
+
+struct efx_mcdi_mon_attribute {
+	struct device_attribute dev_attr;
+	unsigned int index;
+	unsigned int 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);
+	u8 inbuf[MC_CMD_READ_SENSORS_IN_LEN];
+	int rc;
+
+	MCDI_SET_DWORD(inbuf, READ_SENSORS_IN_DMA_ADDR_LO,
+		       hwmon->dma_buf.dma_addr & 0xffffffff);
+	MCDI_SET_DWORD(inbuf, READ_SENSORS_IN_DMA_ADDR_HI,
+		       (u64)hwmon->dma_buf.dma_addr >> 32);
+
+	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 ssize_t efx_mcdi_mon_show_name(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	return sprintf(buf, "%s\n", KBUILD_MODNAME);
+}
+
+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);
+	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;
+	int rc;
+
+	rc = efx_mcdi_mon_get_entry(dev, mon_attr->index, &entry);
+	if (rc)
+		return rc;
+
+	value = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_VALUE);
+
+	/* Convert temperature from degrees to milli-degrees Celsius */
+	if (efx_mcdi_sensor_type[mon_attr->type].hwmon_type == EFX_HWMON_TEMP)
+		value *= 1000;
+
+	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;
+
+	/* Convert temperature from degrees to milli-degrees Celsius */
+	if (efx_mcdi_sensor_type[mon_attr->type].hwmon_type == EFX_HWMON_TEMP)
+		value *= 1000;
+
+	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 int
+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];
+	int rc;
+
+	strlcpy(attr->name, name, sizeof(attr->name));
+	attr->index = index;
+	attr->type = type;
+	attr->limit_value = limit_value;
+	attr->dev_attr.attr.name = attr->name;
+	attr->dev_attr.attr.mode = S_IRUGO;
+	attr->dev_attr.show = reader;
+	rc = device_create_file(&efx->pci_dev->dev, &attr->dev_attr);
+	if (rc == 0)
+		++hwmon->n_attrs;
+	return rc;
+}
+
+int efx_mcdi_mon_probe(struct efx_nic *efx)
+{
+	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
+	unsigned int n_attrs, n_temp = 0, n_cool = 0, n_in = 0;
+	u8 outbuf[MC_CMD_SENSOR_INFO_OUT_LENMAX];
+	size_t outlen;
+	char name[12];
+	u32 mask;
+	int rc, i, type;
+
+	BUILD_BUG_ON(MC_CMD_SENSOR_INFO_IN_LEN != 0);
+
+	rc = efx_mcdi_rpc(efx, MC_CMD_SENSOR_INFO, NULL, 0,
+			  outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	if (outlen < MC_CMD_SENSOR_INFO_OUT_LENMIN)
+		return -EIO;
+
+	/* Find out which sensors are present.  Don't create a device
+	 * if there are none.
+	 */
+	mask = MCDI_DWORD(outbuf, SENSOR_INFO_OUT_MASK);
+	if (mask == 0)
+		return 0;
+
+	/* Check again for short response */
+	if (outlen < MC_CMD_SENSOR_INFO_OUT_LEN(hweight32(mask)))
+		return -EIO;
+
+	rc = efx_nic_alloc_buffer(efx, &hwmon->dma_buf,
+				  4 * MC_CMD_SENSOR_ENTRY_MAXNUM);
+	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: name of the driver plus
+	 * value, min, max, crit, alarm and label for each sensor.
+	 */
+	n_attrs = 1 + 6 * hweight32(mask);
+	hwmon->attrs = kcalloc(n_attrs, sizeof(*hwmon->attrs), GFP_KERNEL);
+	if (!hwmon->attrs) {
+		rc = -ENOMEM;
+		goto fail;
+	}
+
+	hwmon->device = hwmon_device_register(&efx->pci_dev->dev);
+	if (IS_ERR(hwmon->device)) {
+		rc = PTR_ERR(hwmon->device);
+		goto fail;
+	}
+
+	rc = efx_mcdi_mon_add_attr(efx, "name", efx_mcdi_mon_show_name, 0, 0, 0);
+	if (rc)
+		goto fail;
+
+	for (i = 0, type = -1; ; i++) {
+		const char *hwmon_prefix;
+		unsigned hwmon_index;
+		u16 min1, max1, min2, max2;
+
+		/* Find next sensor type or exit if there is none */
+		type++;
+		while (!(mask & (1 << type))) {
+			type++;
+			if (type == 32)
+				return 0;
+		}
+
+		/* Skip sensors specific to a different port */
+		if (efx_mcdi_sensor_type[type].hwmon_type != EFX_HWMON_UNKNOWN &&
+		    efx_mcdi_sensor_type[type].port >= 0 &&
+		    efx_mcdi_sensor_type[type].port != efx_port_num(efx))
+			continue;
+
+		switch (efx_mcdi_sensor_type[type].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;
+		}
+
+		min1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, i, MIN1);
+		max1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, i, MAX1);
+		min2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, i, MIN2);
+		max2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
+					SENSOR_INFO_ENTRY, i, MAX2);
+
+		if (min1 != max1) {
+			snprintf(name, sizeof(name), "%s%u_input",
+				 hwmon_prefix, hwmon_index);
+			rc = efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_value, i, type, 0);
+			if (rc)
+				goto fail;
+
+			snprintf(name, sizeof(name), "%s%u_min",
+				 hwmon_prefix, hwmon_index);
+			rc = efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_limit,
+				i, type, min1);
+			if (rc)
+				goto fail;
+
+			snprintf(name, sizeof(name), "%s%u_max",
+				 hwmon_prefix, hwmon_index);
+			rc = efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_limit,
+				i, type, max1);
+			if (rc)
+				goto fail;
+
+			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);
+				rc = efx_mcdi_mon_add_attr(
+					efx, name, efx_mcdi_mon_show_limit,
+					i, type, max2);
+				if (rc)
+					goto fail;
+			}
+		}
+
+		snprintf(name, sizeof(name), "%s%u_alarm",
+			 hwmon_prefix, hwmon_index);
+		rc = efx_mcdi_mon_add_attr(
+			efx, name, efx_mcdi_mon_show_alarm, i, type, 0);
+		if (rc)
+			goto fail;
+
+		if (efx_mcdi_sensor_type[type].label) {
+			snprintf(name, sizeof(name), "%s%u_label",
+				 hwmon_prefix, hwmon_index);
+			rc = efx_mcdi_mon_add_attr(
+				efx, name, efx_mcdi_mon_show_label, i, type, 0);
+			if (rc)
+				goto fail;
+		}
+	}
+
+fail:
+	efx_mcdi_mon_remove(efx);
+	return rc;
+}
+
+void efx_mcdi_mon_remove(struct efx_nic *efx)
+{
+	struct siena_nic_data *nic_data = efx->nic_data;
+	struct efx_mcdi_mon *hwmon = &nic_data->hwmon;
+	unsigned int i;
+
+	for (i = 0; i < hwmon->n_attrs; i++)
+		device_remove_file(&efx->pci_dev->dev,
+				   &hwmon->attrs[i].dev_attr);
+	kfree(hwmon->attrs);
+	if (hwmon->device)
+		hwmon_device_unregister(hwmon->device);
+	efx_nic_free_buffer(efx, &hwmon->dma_buf);
+}
+
+#endif /* CONFIG_SFC_MCDI_MON */