--- /dev/null
+/* bbc_envctrl.c: UltraSPARC-III environment control driver.
+ *
+ * Copyright (C) 2001, 2008 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/kmod.h>
+#include <linux/reboot.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <asm/oplib.h>
+
+#include "bbc_i2c.h"
+#include "max1617.h"
+
+#undef ENVCTRL_TRACE
+
+/* WARNING: Making changes to this driver is very dangerous.
+ * If you misprogram the sensor chips they can
+ * cut the power on you instantly.
+ */
+
+/* Two temperature sensors exist in the SunBLADE-1000 enclosure.
+ * Both are implemented using max1617 i2c devices. Each max1617
+ * monitors 2 temperatures, one for one of the cpu dies and the other
+ * for the ambient temperature.
+ *
+ * The max1617 is capable of being programmed with power-off
+ * temperature values, one low limit and one high limit. These
+ * can be controlled independently for the cpu or ambient temperature.
+ * If a limit is violated, the power is simply shut off. The frequency
+ * with which the max1617 does temperature sampling can be controlled
+ * as well.
+ *
+ * Three fans exist inside the machine, all three are controlled with
+ * an i2c digital to analog converter. There is a fan directed at the
+ * two processor slots, another for the rest of the enclosure, and the
+ * third is for the power supply. The first two fans may be speed
+ * controlled by changing the voltage fed to them. The third fan may
+ * only be completely off or on. The third fan is meant to only be
+ * disabled/enabled when entering/exiting the lowest power-saving
+ * mode of the machine.
+ *
+ * An environmental control kernel thread periodically monitors all
+ * temperature sensors. Based upon the samples it will adjust the
+ * fan speeds to try and keep the system within a certain temperature
+ * range (the goal being to make the fans as quiet as possible without
+ * allowing the system to get too hot).
+ *
+ * If the temperature begins to rise/fall outside of the acceptable
+ * operating range, a periodic warning will be sent to the kernel log.
+ * The fans will be put on full blast to attempt to deal with this
+ * situation. After exceeding the acceptable operating range by a
+ * certain threshold, the kernel thread will shut down the system.
+ * Here, the thread is attempting to shut the machine down cleanly
+ * before the hardware based power-off event is triggered.
+ */
+
+/* These settings are in Celsius. We use these defaults only
+ * if we cannot interrogate the cpu-fru SEEPROM.
+ */
+struct temp_limits {
+ s8 high_pwroff, high_shutdown, high_warn;
+ s8 low_warn, low_shutdown, low_pwroff;
+};
+
+static struct temp_limits cpu_temp_limits[2] = {
+ { 100, 85, 80, 5, -5, -10 },
+ { 100, 85, 80, 5, -5, -10 },
+};
+
+static struct temp_limits amb_temp_limits[2] = {
+ { 65, 55, 40, 5, -5, -10 },
+ { 65, 55, 40, 5, -5, -10 },
+};
+
+static LIST_HEAD(all_temps);
+static LIST_HEAD(all_fans);
+
+#define CPU_FAN_REG 0xf0
+#define SYS_FAN_REG 0xf2
+#define PSUPPLY_FAN_REG 0xf4
+
+#define FAN_SPEED_MIN 0x0c
+#define FAN_SPEED_MAX 0x3f
+
+#define PSUPPLY_FAN_ON 0x1f
+#define PSUPPLY_FAN_OFF 0x00
+
+static void set_fan_speeds(struct bbc_fan_control *fp)
+{
+ /* Put temperatures into range so we don't mis-program
+ * the hardware.
+ */
+ if (fp->cpu_fan_speed < FAN_SPEED_MIN)
+ fp->cpu_fan_speed = FAN_SPEED_MIN;
+ if (fp->cpu_fan_speed > FAN_SPEED_MAX)
+ fp->cpu_fan_speed = FAN_SPEED_MAX;
+ if (fp->system_fan_speed < FAN_SPEED_MIN)
+ fp->system_fan_speed = FAN_SPEED_MIN;
+ if (fp->system_fan_speed > FAN_SPEED_MAX)
+ fp->system_fan_speed = FAN_SPEED_MAX;
+#ifdef ENVCTRL_TRACE
+ printk("fan%d: Changed fan speed to cpu(%02x) sys(%02x)\n",
+ fp->index,
+ fp->cpu_fan_speed, fp->system_fan_speed);
+#endif
+
+ bbc_i2c_writeb(fp->client, fp->cpu_fan_speed, CPU_FAN_REG);
+ bbc_i2c_writeb(fp->client, fp->system_fan_speed, SYS_FAN_REG);
+ bbc_i2c_writeb(fp->client,
+ (fp->psupply_fan_on ?
+ PSUPPLY_FAN_ON : PSUPPLY_FAN_OFF),
+ PSUPPLY_FAN_REG);
+}
+
+static void get_current_temps(struct bbc_cpu_temperature *tp)
+{
+ tp->prev_amb_temp = tp->curr_amb_temp;
+ bbc_i2c_readb(tp->client,
+ (unsigned char *) &tp->curr_amb_temp,
+ MAX1617_AMB_TEMP);
+ tp->prev_cpu_temp = tp->curr_cpu_temp;
+ bbc_i2c_readb(tp->client,
+ (unsigned char *) &tp->curr_cpu_temp,
+ MAX1617_CPU_TEMP);
+#ifdef ENVCTRL_TRACE
+ printk("temp%d: cpu(%d C) amb(%d C)\n",
+ tp->index,
+ (int) tp->curr_cpu_temp, (int) tp->curr_amb_temp);
+#endif
+}
+
+
+static void do_envctrl_shutdown(struct bbc_cpu_temperature *tp)
+{
+ static int shutting_down = 0;
+ char *type = "???";
+ s8 val = -1;
+
+ if (shutting_down != 0)
+ return;
+
+ if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_shutdown ||
+ tp->curr_amb_temp < amb_temp_limits[tp->index].low_shutdown) {
+ type = "ambient";
+ val = tp->curr_amb_temp;
+ } else if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_shutdown ||
+ tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_shutdown) {
+ type = "CPU";
+ val = tp->curr_cpu_temp;
+ }
+
+ printk(KERN_CRIT "temp%d: Outside of safe %s "
+ "operating temperature, %d C.\n",
+ tp->index, type, val);
+
+ printk(KERN_CRIT "kenvctrld: Shutting down the system now.\n");
+
+ shutting_down = 1;
+ orderly_poweroff(true);
+}
+
+#define WARN_INTERVAL (30 * HZ)
+
+static void analyze_ambient_temp(struct bbc_cpu_temperature *tp, unsigned long *last_warn, int tick)
+{
+ int ret = 0;
+
+ if (time_after(jiffies, (*last_warn + WARN_INTERVAL))) {
+ if (tp->curr_amb_temp >=
+ amb_temp_limits[tp->index].high_warn) {
+ printk(KERN_WARNING "temp%d: "
+ "Above safe ambient operating temperature, %d C.\n",
+ tp->index, (int) tp->curr_amb_temp);
+ ret = 1;
+ } else if (tp->curr_amb_temp <
+ amb_temp_limits[tp->index].low_warn) {
+ printk(KERN_WARNING "temp%d: "
+ "Below safe ambient operating temperature, %d C.\n",
+ tp->index, (int) tp->curr_amb_temp);
+ ret = 1;
+ }
+ if (ret)
+ *last_warn = jiffies;
+ } else if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_warn ||
+ tp->curr_amb_temp < amb_temp_limits[tp->index].low_warn)
+ ret = 1;
+
+ /* Now check the shutdown limits. */
+ if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_shutdown ||
+ tp->curr_amb_temp < amb_temp_limits[tp->index].low_shutdown) {
+ do_envctrl_shutdown(tp);
+ ret = 1;
+ }
+
+ if (ret) {
+ tp->fan_todo[FAN_AMBIENT] = FAN_FULLBLAST;
+ } else if ((tick & (8 - 1)) == 0) {
+ s8 amb_goal_hi = amb_temp_limits[tp->index].high_warn - 10;
+ s8 amb_goal_lo;
+
+ amb_goal_lo = amb_goal_hi - 3;
+
+ /* We do not try to avoid 'too cold' events. Basically we
+ * only try to deal with over-heating and fan noise reduction.
+ */
+ if (tp->avg_amb_temp < amb_goal_hi) {
+ if (tp->avg_amb_temp >= amb_goal_lo)
+ tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
+ else
+ tp->fan_todo[FAN_AMBIENT] = FAN_SLOWER;
+ } else {
+ tp->fan_todo[FAN_AMBIENT] = FAN_FASTER;
+ }
+ } else {
+ tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
+ }
+}
+
+static void analyze_cpu_temp(struct bbc_cpu_temperature *tp, unsigned long *last_warn, int tick)
+{
+ int ret = 0;
+
+ if (time_after(jiffies, (*last_warn + WARN_INTERVAL))) {
+ if (tp->curr_cpu_temp >=
+ cpu_temp_limits[tp->index].high_warn) {
+ printk(KERN_WARNING "temp%d: "
+ "Above safe CPU operating temperature, %d C.\n",
+ tp->index, (int) tp->curr_cpu_temp);
+ ret = 1;
+ } else if (tp->curr_cpu_temp <
+ cpu_temp_limits[tp->index].low_warn) {
+ printk(KERN_WARNING "temp%d: "
+ "Below safe CPU operating temperature, %d C.\n",
+ tp->index, (int) tp->curr_cpu_temp);
+ ret = 1;
+ }
+ if (ret)
+ *last_warn = jiffies;
+ } else if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_warn ||
+ tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_warn)
+ ret = 1;
+
+ /* Now check the shutdown limits. */
+ if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_shutdown ||
+ tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_shutdown) {
+ do_envctrl_shutdown(tp);
+ ret = 1;
+ }
+
+ if (ret) {
+ tp->fan_todo[FAN_CPU] = FAN_FULLBLAST;
+ } else if ((tick & (8 - 1)) == 0) {
+ s8 cpu_goal_hi = cpu_temp_limits[tp->index].high_warn - 10;
+ s8 cpu_goal_lo;
+
+ cpu_goal_lo = cpu_goal_hi - 3;
+
+ /* We do not try to avoid 'too cold' events. Basically we
+ * only try to deal with over-heating and fan noise reduction.
+ */
+ if (tp->avg_cpu_temp < cpu_goal_hi) {
+ if (tp->avg_cpu_temp >= cpu_goal_lo)
+ tp->fan_todo[FAN_CPU] = FAN_SAME;
+ else
+ tp->fan_todo[FAN_CPU] = FAN_SLOWER;
+ } else {
+ tp->fan_todo[FAN_CPU] = FAN_FASTER;
+ }
+ } else {
+ tp->fan_todo[FAN_CPU] = FAN_SAME;
+ }
+}
+
+static void analyze_temps(struct bbc_cpu_temperature *tp, unsigned long *last_warn)
+{
+ tp->avg_amb_temp = (s8)((int)((int)tp->avg_amb_temp + (int)tp->curr_amb_temp) / 2);
+ tp->avg_cpu_temp = (s8)((int)((int)tp->avg_cpu_temp + (int)tp->curr_cpu_temp) / 2);
+
+ analyze_ambient_temp(tp, last_warn, tp->sample_tick);
+ analyze_cpu_temp(tp, last_warn, tp->sample_tick);
+
+ tp->sample_tick++;
+}
+
+static enum fan_action prioritize_fan_action(int which_fan)
+{
+ struct bbc_cpu_temperature *tp;
+ enum fan_action decision = FAN_STATE_MAX;
+
+ /* Basically, prioritize what the temperature sensors
+ * recommend we do, and perform that action on all the
+ * fans.
+ */
+ list_for_each_entry(tp, &all_temps, glob_list) {
+ if (tp->fan_todo[which_fan] == FAN_FULLBLAST) {
+ decision = FAN_FULLBLAST;
+ break;
+ }
+ if (tp->fan_todo[which_fan] == FAN_SAME &&
+ decision != FAN_FASTER)
+ decision = FAN_SAME;
+ else if (tp->fan_todo[which_fan] == FAN_FASTER)
+ decision = FAN_FASTER;
+ else if (decision != FAN_FASTER &&
+ decision != FAN_SAME &&
+ tp->fan_todo[which_fan] == FAN_SLOWER)
+ decision = FAN_SLOWER;
+ }
+ if (decision == FAN_STATE_MAX)
+ decision = FAN_SAME;
+
+ return decision;
+}
+
+static int maybe_new_ambient_fan_speed(struct bbc_fan_control *fp)
+{
+ enum fan_action decision = prioritize_fan_action(FAN_AMBIENT);
+ int ret;
+
+ if (decision == FAN_SAME)
+ return 0;
+
+ ret = 1;
+ if (decision == FAN_FULLBLAST) {
+ if (fp->system_fan_speed >= FAN_SPEED_MAX)
+ ret = 0;
+ else
+ fp->system_fan_speed = FAN_SPEED_MAX;
+ } else {
+ if (decision == FAN_FASTER) {
+ if (fp->system_fan_speed >= FAN_SPEED_MAX)
+ ret = 0;
+ else
+ fp->system_fan_speed += 2;
+ } else {
+ int orig_speed = fp->system_fan_speed;
+
+ if (orig_speed <= FAN_SPEED_MIN ||
+ orig_speed <= (fp->cpu_fan_speed - 3))
+ ret = 0;
+ else
+ fp->system_fan_speed -= 1;
+ }
+ }
+
+ return ret;
+}
+
+static int maybe_new_cpu_fan_speed(struct bbc_fan_control *fp)
+{
+ enum fan_action decision = prioritize_fan_action(FAN_CPU);
+ int ret;
+
+ if (decision == FAN_SAME)
+ return 0;
+
+ ret = 1;
+ if (decision == FAN_FULLBLAST) {
+ if (fp->cpu_fan_speed >= FAN_SPEED_MAX)
+ ret = 0;
+ else
+ fp->cpu_fan_speed = FAN_SPEED_MAX;
+ } else {
+ if (decision == FAN_FASTER) {
+ if (fp->cpu_fan_speed >= FAN_SPEED_MAX)
+ ret = 0;
+ else {
+ fp->cpu_fan_speed += 2;
+ if (fp->system_fan_speed <
+ (fp->cpu_fan_speed - 3))
+ fp->system_fan_speed =
+ fp->cpu_fan_speed - 3;
+ }
+ } else {
+ if (fp->cpu_fan_speed <= FAN_SPEED_MIN)
+ ret = 0;
+ else
+ fp->cpu_fan_speed -= 1;
+ }
+ }
+
+ return ret;
+}
+
+static void maybe_new_fan_speeds(struct bbc_fan_control *fp)
+{
+ int new;
+
+ new = maybe_new_ambient_fan_speed(fp);
+ new |= maybe_new_cpu_fan_speed(fp);
+
+ if (new)
+ set_fan_speeds(fp);
+}
+
+static void fans_full_blast(void)
+{
+ struct bbc_fan_control *fp;
+
+ /* Since we will not be monitoring things anymore, put
+ * the fans on full blast.
+ */
+ list_for_each_entry(fp, &all_fans, glob_list) {
+ fp->cpu_fan_speed = FAN_SPEED_MAX;
+ fp->system_fan_speed = FAN_SPEED_MAX;
+ fp->psupply_fan_on = 1;
+ set_fan_speeds(fp);
+ }
+}
+
+#define POLL_INTERVAL (5 * 1000)
+static unsigned long last_warning_jiffies;
+static struct task_struct *kenvctrld_task;
+
+static int kenvctrld(void *__unused)
+{
+ printk(KERN_INFO "bbc_envctrl: kenvctrld starting...\n");
+ last_warning_jiffies = jiffies - WARN_INTERVAL;
+ for (;;) {
+ struct bbc_cpu_temperature *tp;
+ struct bbc_fan_control *fp;
+
+ msleep_interruptible(POLL_INTERVAL);
+ if (kthread_should_stop())
+ break;
+
+ list_for_each_entry(tp, &all_temps, glob_list) {
+ get_current_temps(tp);
+ analyze_temps(tp, &last_warning_jiffies);
+ }
+ list_for_each_entry(fp, &all_fans, glob_list)
+ maybe_new_fan_speeds(fp);
+ }
+ printk(KERN_INFO "bbc_envctrl: kenvctrld exiting...\n");
+
+ fans_full_blast();
+
+ return 0;
+}
+
+static void attach_one_temp(struct bbc_i2c_bus *bp, struct platform_device *op,
+ int temp_idx)
+{
+ struct bbc_cpu_temperature *tp;
+
+ tp = kzalloc(sizeof(*tp), GFP_KERNEL);
+ if (!tp)
+ return;
+
+ INIT_LIST_HEAD(&tp->bp_list);
+ INIT_LIST_HEAD(&tp->glob_list);
+
+ tp->client = bbc_i2c_attach(bp, op);
+ if (!tp->client) {
+ kfree(tp);
+ return;
+ }
+
+
+ tp->index = temp_idx;
+
+ list_add(&tp->glob_list, &all_temps);
+ list_add(&tp->bp_list, &bp->temps);
+
+ /* Tell it to convert once every 5 seconds, clear all cfg
+ * bits.
+ */
+ bbc_i2c_writeb(tp->client, 0x00, MAX1617_WR_CFG_BYTE);
+ bbc_i2c_writeb(tp->client, 0x02, MAX1617_WR_CVRATE_BYTE);
+
+ /* Program the hard temperature limits into the chip. */
+ bbc_i2c_writeb(tp->client, amb_temp_limits[tp->index].high_pwroff,
+ MAX1617_WR_AMB_HIGHLIM);
+ bbc_i2c_writeb(tp->client, amb_temp_limits[tp->index].low_pwroff,
+ MAX1617_WR_AMB_LOWLIM);
+ bbc_i2c_writeb(tp->client, cpu_temp_limits[tp->index].high_pwroff,
+ MAX1617_WR_CPU_HIGHLIM);
+ bbc_i2c_writeb(tp->client, cpu_temp_limits[tp->index].low_pwroff,
+ MAX1617_WR_CPU_LOWLIM);
+
+ get_current_temps(tp);
+ tp->prev_cpu_temp = tp->avg_cpu_temp = tp->curr_cpu_temp;
+ tp->prev_amb_temp = tp->avg_amb_temp = tp->curr_amb_temp;
+
+ tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
+ tp->fan_todo[FAN_CPU] = FAN_SAME;
+}
+
+static void attach_one_fan(struct bbc_i2c_bus *bp, struct platform_device *op,
+ int fan_idx)
+{
+ struct bbc_fan_control *fp;
+
+ fp = kzalloc(sizeof(*fp), GFP_KERNEL);
+ if (!fp)
+ return;
+
+ INIT_LIST_HEAD(&fp->bp_list);
+ INIT_LIST_HEAD(&fp->glob_list);
+
+ fp->client = bbc_i2c_attach(bp, op);
+ if (!fp->client) {
+ kfree(fp);
+ return;
+ }
+
+ fp->index = fan_idx;
+
+ list_add(&fp->glob_list, &all_fans);
+ list_add(&fp->bp_list, &bp->fans);
+
+ /* The i2c device controlling the fans is write-only.
+ * So the only way to keep track of the current power
+ * level fed to the fans is via software. Choose half
+ * power for cpu/system and 'on' fo the powersupply fan
+ * and set it now.
+ */
+ fp->psupply_fan_on = 1;
+ fp->cpu_fan_speed = (FAN_SPEED_MAX - FAN_SPEED_MIN) / 2;
+ fp->cpu_fan_speed += FAN_SPEED_MIN;
+ fp->system_fan_speed = (FAN_SPEED_MAX - FAN_SPEED_MIN) / 2;
+ fp->system_fan_speed += FAN_SPEED_MIN;
+
+ set_fan_speeds(fp);
+}
+
+static void destroy_one_temp(struct bbc_cpu_temperature *tp)
+{
+ bbc_i2c_detach(tp->client);
+ kfree(tp);
+}
+
+static void destroy_all_temps(struct bbc_i2c_bus *bp)
+{
+ struct bbc_cpu_temperature *tp, *tpos;
+
+ list_for_each_entry_safe(tp, tpos, &bp->temps, bp_list) {
+ list_del(&tp->bp_list);
+ list_del(&tp->glob_list);
+ destroy_one_temp(tp);
+ }
+}
+
+static void destroy_one_fan(struct bbc_fan_control *fp)
+{
+ bbc_i2c_detach(fp->client);
+ kfree(fp);
+}
+
+static void destroy_all_fans(struct bbc_i2c_bus *bp)
+{
+ struct bbc_fan_control *fp, *fpos;
+
+ list_for_each_entry_safe(fp, fpos, &bp->fans, bp_list) {
+ list_del(&fp->bp_list);
+ list_del(&fp->glob_list);
+ destroy_one_fan(fp);
+ }
+}
+
+int bbc_envctrl_init(struct bbc_i2c_bus *bp)
+{
+ struct platform_device *op;
+ int temp_index = 0;
+ int fan_index = 0;
+ int devidx = 0;
+
+ while ((op = bbc_i2c_getdev(bp, devidx++)) != NULL) {
+ if (!strcmp(op->dev.of_node->name, "temperature"))
+ attach_one_temp(bp, op, temp_index++);
+ if (!strcmp(op->dev.of_node->name, "fan-control"))
+ attach_one_fan(bp, op, fan_index++);
+ }
+ if (temp_index != 0 && fan_index != 0) {
+ kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
+ if (IS_ERR(kenvctrld_task)) {
+ int err = PTR_ERR(kenvctrld_task);
+
+ kenvctrld_task = NULL;
+ destroy_all_temps(bp);
+ destroy_all_fans(bp);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+void bbc_envctrl_cleanup(struct bbc_i2c_bus *bp)
+{
+ if (kenvctrld_task)
+ kthread_stop(kenvctrld_task);
+
+ destroy_all_temps(bp);
+ destroy_all_fans(bp);
+}
Code Review / kvmfornfv.git / blobdiff