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Release 4.14 drivers/macintosh/windfarm_rm31.c

/*
 * Windfarm PowerMac thermal control.
 * Control loops for RackMack3,1 (Xserve G5)
 *
 * Copyright (C) 2012 Benjamin Herrenschmidt, IBM Corp.
 *
 * Use and redistribute under the terms of the GNU GPL v2.
 */
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <asm/prom.h>
#include <asm/smu.h>

#include "windfarm.h"
#include "windfarm_pid.h"
#include "windfarm_mpu.h"


#define VERSION "1.0"


#undef DEBUG

#undef LOTSA_DEBUG

#ifdef DEBUG

#define DBG(args...)	printk(args)
#else

#define DBG(args...)	do { } while(0)
#endif

#ifdef LOTSA_DEBUG

#define DBG_LOTS(args...)	printk(args)
#else

#define DBG_LOTS(args...)	do { } while(0)
#endif

/* define this to force CPU overtemp to 60 degree, useful for testing
 * the overtemp code
 */

#undef HACKED_OVERTEMP

/* We currently only handle 2 chips */

#define NR_CHIPS	2

#define NR_CPU_FANS	3 * NR_CHIPS

/* Controls and sensors */

static struct wf_sensor *sens_cpu_temp[NR_CHIPS];

static struct wf_sensor *sens_cpu_volts[NR_CHIPS];

static struct wf_sensor *sens_cpu_amps[NR_CHIPS];

static struct wf_sensor *backside_temp;

static struct wf_sensor *slots_temp;

static struct wf_sensor *dimms_temp;


static struct wf_control *cpu_fans[NR_CHIPS][3];

static struct wf_control *backside_fan;

static struct wf_control *slots_fan;

static struct wf_control *cpufreq_clamp;

/* We keep a temperature history for average calculation of 180s */

#define CPU_TEMP_HIST_SIZE	180

/* PID loop state */

static const struct mpu_data *cpu_mpu_data[NR_CHIPS];

static struct wf_cpu_pid_state cpu_pid[NR_CHIPS];

static u32 cpu_thist[CPU_TEMP_HIST_SIZE];

static int cpu_thist_pt;

static s64 cpu_thist_total;

static s32 cpu_all_tmax = 100 << 16;

static struct wf_pid_state backside_pid;

static int backside_tick;

static struct wf_pid_state slots_pid;

static int slots_tick;

static int slots_speed;

static struct wf_pid_state dimms_pid;

static int dimms_output_clamp;


static int nr_chips;

static bool have_all_controls;

static bool have_all_sensors;

static bool started;


static int failure_state;

#define FAILURE_SENSOR		1

#define FAILURE_FAN		2

#define FAILURE_PERM		4

#define FAILURE_LOW_OVERTEMP	8

#define FAILURE_HIGH_OVERTEMP	16

/* Overtemp values */

#define LOW_OVER_AVERAGE	0

#define LOW_OVER_IMMEDIATE	(10 << 16)

#define LOW_OVER_CLEAR		((-10) << 16)

#define HIGH_OVER_IMMEDIATE	(14 << 16)

#define HIGH_OVER_AVERAGE	(10 << 16)

#define HIGH_OVER_IMMEDIATE	(14 << 16)



static void cpu_max_all_fans(void) { int i; /* We max all CPU fans in case of a sensor error. We also do the * cpufreq clamping now, even if it's supposedly done later by the * generic code anyway, we do it earlier here to react faster */ if (cpufreq_clamp) wf_control_set_max(cpufreq_clamp); for (i = 0; i < nr_chips; i++) { if (cpu_fans[i][0]) wf_control_set_max(cpu_fans[i][0]); if (cpu_fans[i][1]) wf_control_set_max(cpu_fans[i][1]); if (cpu_fans[i][2]) wf_control_set_max(cpu_fans[i][2]); } }

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Benjamin Herrenschmidt99100.00%1100.00%
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static int cpu_check_overtemp(s32 temp) { int new_state = 0; s32 t_avg, t_old; static bool first = true; /* First check for immediate overtemps */ if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) { new_state |= FAILURE_LOW_OVERTEMP; if ((failure_state & FAILURE_LOW_OVERTEMP) == 0) printk(KERN_ERR "windfarm: Overtemp due to immediate CPU" " temperature !\n"); } if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) { new_state |= FAILURE_HIGH_OVERTEMP; if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0) printk(KERN_ERR "windfarm: Critical overtemp due to" " immediate CPU temperature !\n"); } /* * The first time around, initialize the array with the first * temperature reading */ if (first) { int i; cpu_thist_total = 0; for (i = 0; i < CPU_TEMP_HIST_SIZE; i++) { cpu_thist[i] = temp; cpu_thist_total += temp; } first = false; } /* * We calculate a history of max temperatures and use that for the * overtemp management */ t_old = cpu_thist[cpu_thist_pt]; cpu_thist[cpu_thist_pt] = temp; cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE; cpu_thist_total -= t_old; cpu_thist_total += temp; t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE; DBG_LOTS(" t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n", FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp)); /* Now check for average overtemps */ if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) { new_state |= FAILURE_LOW_OVERTEMP; if ((failure_state & FAILURE_LOW_OVERTEMP) == 0) printk(KERN_ERR "windfarm: Overtemp due to average CPU" " temperature !\n"); } if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) { new_state |= FAILURE_HIGH_OVERTEMP; if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0) printk(KERN_ERR "windfarm: Critical overtemp due to" " average CPU temperature !\n"); } /* Now handle overtemp conditions. We don't currently use the windfarm * overtemp handling core as it's not fully suited to the needs of those * new machine. This will be fixed later. */ if (new_state) { /* High overtemp -> immediate shutdown */ if (new_state & FAILURE_HIGH_OVERTEMP) machine_power_off(); if ((failure_state & new_state) != new_state) cpu_max_all_fans(); failure_state |= new_state; } else if ((failure_state & FAILURE_LOW_OVERTEMP) && (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) { printk(KERN_ERR "windfarm: Overtemp condition cleared !\n"); failure_state &= ~FAILURE_LOW_OVERTEMP; } return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP); }

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Benjamin Herrenschmidt337100.00%1100.00%
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static int read_one_cpu_vals(int cpu, s32 *temp, s32 *power) { s32 dtemp, volts, amps; int rc; /* Get diode temperature */ rc = wf_sensor_get(sens_cpu_temp[cpu], &dtemp); if (rc) { DBG(" CPU%d: temp reading error !\n", cpu); return -EIO; } DBG_LOTS(" CPU%d: temp = %d.%03d\n", cpu, FIX32TOPRINT((dtemp))); *temp = dtemp; /* Get voltage */ rc = wf_sensor_get(sens_cpu_volts[cpu], &volts); if (rc) { DBG(" CPU%d, volts reading error !\n", cpu); return -EIO; } DBG_LOTS(" CPU%d: volts = %d.%03d\n", cpu, FIX32TOPRINT((volts))); /* Get current */ rc = wf_sensor_get(sens_cpu_amps[cpu], &amps); if (rc) { DBG(" CPU%d, current reading error !\n", cpu); return -EIO; } DBG_LOTS(" CPU%d: amps = %d.%03d\n", cpu, FIX32TOPRINT((amps))); /* Calculate power */ /* Scale voltage and current raw sensor values according to fixed scales * obtained in Darwin and calculate power from I and V */ *power = (((u64)volts) * ((u64)amps)) >> 16; DBG_LOTS(" CPU%d: power = %d.%03d\n", cpu, FIX32TOPRINT((*power))); return 0; }

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Benjamin Herrenschmidt208100.00%1100.00%
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static void cpu_fans_tick(void) { int err, cpu, i; s32 speed, temp, power, t_max = 0; DBG_LOTS("* cpu fans_tick_split()\n"); for (cpu = 0; cpu < nr_chips; ++cpu) { struct wf_cpu_pid_state *sp = &cpu_pid[cpu]; /* Read current speed */ wf_control_get(cpu_fans[cpu][0], &sp->target); err = read_one_cpu_vals(cpu, &temp, &power); if (err) { failure_state |= FAILURE_SENSOR; cpu_max_all_fans(); return; } /* Keep track of highest temp */ t_max = max(t_max, temp); /* Handle possible overtemps */ if (cpu_check_overtemp(t_max)) return; /* Run PID */ wf_cpu_pid_run(sp, power, temp); DBG_LOTS(" CPU%d: target = %d RPM\n", cpu, sp->target); /* Apply DIMMs clamp */ speed = max(sp->target, dimms_output_clamp); /* Apply result to all cpu fans */ for (i = 0; i < 3; i++) { err = wf_control_set(cpu_fans[cpu][i], speed); if (err) { pr_warning("wf_rm31: Fan %s reports error %d\n", cpu_fans[cpu][i]->name, err); failure_state |= FAILURE_FAN; } } } }

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Benjamin Herrenschmidt211100.00%1100.00%
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/* Implementation... */
static int cpu_setup_pid(int cpu) { struct wf_cpu_pid_param pid; const struct mpu_data *mpu = cpu_mpu_data[cpu]; s32 tmax, ttarget, ptarget; int fmin, fmax, hsize; /* Get PID params from the appropriate MPU EEPROM */ tmax = mpu->tmax << 16; ttarget = mpu->ttarget << 16; ptarget = ((s32)(mpu->pmaxh - mpu->padjmax)) << 16; DBG("wf_72: CPU%d ttarget = %d.%03d, tmax = %d.%03d\n", cpu, FIX32TOPRINT(ttarget), FIX32TOPRINT(tmax)); /* We keep a global tmax for overtemp calculations */ if (tmax < cpu_all_tmax) cpu_all_tmax = tmax; /* Set PID min/max by using the rear fan min/max */ fmin = wf_control_get_min(cpu_fans[cpu][0]); fmax = wf_control_get_max(cpu_fans[cpu][0]); DBG("wf_72: CPU%d max RPM range = [%d..%d]\n", cpu, fmin, fmax); /* History size */ hsize = min_t(int, mpu->tguardband, WF_PID_MAX_HISTORY); DBG("wf_72: CPU%d history size = %d\n", cpu, hsize); /* Initialize PID loop */ pid.interval = 1; /* seconds */ pid.history_len = hsize; pid.gd = mpu->pid_gd; pid.gp = mpu->pid_gp; pid.gr = mpu->pid_gr; pid.tmax = tmax; pid.ttarget = ttarget; pid.pmaxadj = ptarget; pid.min = fmin; pid.max = fmax; wf_cpu_pid_init(&cpu_pid[cpu], &pid); cpu_pid[cpu].target = 4000; return 0; }

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Benjamin Herrenschmidt255100.00%1100.00%
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/* Backside/U3 fan */ static const struct wf_pid_param backside_param = { .interval = 1, .history_len = 2, .gd = 0x00500000, .gp = 0x0004cccc, .gr = 0, .itarget = 70 << 16, .additive = 0, .min = 20, .max = 100, }; /* DIMMs temperature (clamp the backside fan) */ static const struct wf_pid_param dimms_param = { .interval = 1, .history_len = 20, .gd = 0, .gp = 0, .gr = 0x06553600, .itarget = 50 << 16, .additive = 0, .min = 4000, .max = 14000, };
static void backside_fan_tick(void) { s32 temp, dtemp; int speed, dspeed, fan_min; int err; if (!backside_fan || !backside_temp || !dimms_temp || !backside_tick) return; if (--backside_tick > 0) return; backside_tick = backside_pid.param.interval; DBG_LOTS("* backside fans tick\n"); /* Update fan speed from actual fans */ err = wf_control_get(backside_fan, &speed); if (!err) backside_pid.target = speed; err = wf_sensor_get(backside_temp, &temp); if (err) { printk(KERN_WARNING "windfarm: U3 temp sensor error %d\n", err); failure_state |= FAILURE_SENSOR; wf_control_set_max(backside_fan); return; } speed = wf_pid_run(&backside_pid, temp); DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n", FIX32TOPRINT(temp), speed); err = wf_sensor_get(dimms_temp, &dtemp); if (err) { printk(KERN_WARNING "windfarm: DIMMs temp sensor error %d\n", err); failure_state |= FAILURE_SENSOR; wf_control_set_max(backside_fan); return; } dspeed = wf_pid_run(&dimms_pid, dtemp); dimms_output_clamp = dspeed; fan_min = (dspeed * 100) / 14000; fan_min = max(fan_min, backside_param.min); speed = max(speed, fan_min); err = wf_control_set(backside_fan, speed); if (err) { printk(KERN_WARNING "windfarm: backside fan error %d\n", err); failure_state |= FAILURE_FAN; } }

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Benjamin Herrenschmidt242100.00%1100.00%
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static void backside_setup_pid(void) { /* first time initialize things */ s32 fmin = wf_control_get_min(backside_fan); s32 fmax = wf_control_get_max(backside_fan); struct wf_pid_param param; param = backside_param; param.min = max(param.min, fmin); param.max = min(param.max, fmax); wf_pid_init(&backside_pid, &param); param = dimms_param; wf_pid_init(&dimms_pid, &param); backside_tick = 1; pr_info("wf_rm31: Backside control loop started.\n"); }

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Benjamin Herrenschmidt90100.00%1100.00%
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/* Slots fan */ static const struct wf_pid_param slots_param = { .interval = 1, .history_len = 20, .gd = 0, .gp = 0, .gr = 0x00100000, .itarget = 3200000, .additive = 0, .min = 20, .max = 100, };
static void slots_fan_tick(void) { s32 temp; int speed; int err; if (!slots_fan || !slots_temp || !slots_tick) return; if (--slots_tick > 0) return; slots_tick = slots_pid.param.interval; DBG_LOTS("* slots fans tick\n"); err = wf_sensor_get(slots_temp, &temp); if (err) { pr_warning("wf_rm31: slots temp sensor error %d\n", err); failure_state |= FAILURE_SENSOR; wf_control_set_max(slots_fan); return; } speed = wf_pid_run(&slots_pid, temp); DBG_LOTS("slots PID temp=%d.%.3d speed=%d\n", FIX32TOPRINT(temp), speed); slots_speed = speed; err = wf_control_set(slots_fan, speed); if (err) { printk(KERN_WARNING "windfarm: slots bay fan error %d\n", err); failure_state |= FAILURE_FAN; } }

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Benjamin Herrenschmidt136100.00%1100.00%
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static void slots_setup_pid(void) { /* first time initialize things */ s32 fmin = wf_control_get_min(slots_fan); s32 fmax = wf_control_get_max(slots_fan); struct wf_pid_param param = slots_param; param.min = max(param.min, fmin); param.max = min(param.max, fmax); wf_pid_init(&slots_pid, &param); slots_tick = 1; pr_info("wf_rm31: Slots control loop started.\n"); }

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Benjamin Herrenschmidt75100.00%1100.00%
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static void set_fail_state(void) { cpu_max_all_fans(); if (backside_fan) wf_control_set_max(backside_fan); if (slots_fan) wf_control_set_max(slots_fan); }

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Benjamin Herrenschmidt29100.00%1100.00%
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static void rm31_tick(void) { int i, last_failure; if (!started) { started = 1; printk(KERN_INFO "windfarm: CPUs control loops started.\n"); for (i = 0; i < nr_chips; ++i) { if (cpu_setup_pid(i) < 0) { failure_state = FAILURE_PERM; set_fail_state(); break; } } DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax)); backside_setup_pid(); slots_setup_pid(); #ifdef HACKED_OVERTEMP cpu_all_tmax = 60 << 16; #endif } /* Permanent failure, bail out */ if (failure_state & FAILURE_PERM) return; /* * Clear all failure bits except low overtemp which will be eventually * cleared by the control loop itself */ last_failure = failure_state; failure_state &= FAILURE_LOW_OVERTEMP; backside_fan_tick(); slots_fan_tick(); /* We do CPUs last because they can be clamped high by * DIMM temperature */ cpu_fans_tick(); DBG_LOTS(" last_failure: 0x%x, failure_state: %x\n", last_failure, failure_state); /* Check for failures. Any failure causes cpufreq clamping */ if (failure_state && last_failure == 0 && cpufreq_clamp) wf_control_set_max(cpufreq_clamp); if (failure_state == 0 && last_failure && cpufreq_clamp) wf_control_set_min(cpufreq_clamp); /* That's it for now, we might want to deal with other failures * differently in the future though */ }

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Benjamin Herrenschmidt159100.00%1100.00%
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static void rm31_new_control(struct wf_control *ct) { bool all_controls; if (!strcmp(ct->name, "cpu-fan-a-0")) cpu_fans[0][0] = ct; else if (!strcmp(ct->name, "cpu-fan-b-0")) cpu_fans[0][1] = ct; else if (!strcmp(ct->name, "cpu-fan-c-0")) cpu_fans[0][2] = ct; else if (!strcmp(ct->name, "cpu-fan-a-1")) cpu_fans[1][0] = ct; else if (!strcmp(ct->name, "cpu-fan-b-1")) cpu_fans[1][1] = ct; else if (!strcmp(ct->name, "cpu-fan-c-1")) cpu_fans[1][2] = ct; else if (!strcmp(ct->name, "backside-fan")) backside_fan = ct; else if (!strcmp(ct->name, "slots-fan")) slots_fan = ct; else if (!strcmp(ct->name, "cpufreq-clamp")) cpufreq_clamp = ct; all_controls = cpu_fans[0][0] && cpu_fans[0][1] && cpu_fans[0][2] && backside_fan && slots_fan; if (nr_chips > 1) all_controls &= cpu_fans[1][0] && cpu_fans[1][1] && cpu_fans[1][2]; have_all_controls = all_controls; }

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Benjamin Herrenschmidt268100.00%1100.00%
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static void rm31_new_sensor(struct wf_sensor *sr) { bool all_sensors; if (!strcmp(sr->name, "cpu-diode-temp-0")) sens_cpu_temp[0] = sr; else if (!strcmp(sr->name, "cpu-diode-temp-1")) sens_cpu_temp[1] = sr; else if (!strcmp(sr->name, "cpu-voltage-0")) sens_cpu_volts[0] = sr; else if (!strcmp(sr->name, "cpu-voltage-1")) sens_cpu_volts[1] = sr; else if (!strcmp(sr->name, "cpu-current-0")) sens_cpu_amps[0] = sr; else if (!strcmp(sr->name, "cpu-current-1")) sens_cpu_amps[1] = sr; else if (!strcmp(sr->name, "backside-temp")) backside_temp = sr; else if (!strcmp(sr->name, "slots-temp")) slots_temp = sr; else if (!strcmp(sr->name, "dimms-temp")) dimms_temp = sr; all_sensors = sens_cpu_temp[0] && sens_cpu_volts[0] && sens_cpu_amps[0] && backside_temp && slots_temp && dimms_temp; if (nr_chips > 1) all_sensors &= sens_cpu_temp[1] && sens_cpu_volts[1] && sens_cpu_amps[1]; have_all_sensors = all_sensors; }

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Benjamin Herrenschmidt234100.00%1100.00%
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static int rm31_wf_notify(struct notifier_block *self, unsigned long event, void *data) { switch (event) { case WF_EVENT_NEW_SENSOR: rm31_new_sensor(data); break; case WF_EVENT_NEW_CONTROL: rm31_new_control(data); break; case WF_EVENT_TICK: if (have_all_controls && have_all_sensors) rm31_tick(); } return 0; }

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Benjamin Herrenschmidt58100.00%1100.00%
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static struct notifier_block rm31_events = { .notifier_call = rm31_wf_notify, };
static int wf_rm31_probe(struct platform_device *dev) { wf_register_client(&rm31_events); return 0; }

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Benjamin Herrenschmidt20100.00%1100.00%
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static int wf_rm31_remove(struct platform_device *dev) { wf_unregister_client(&rm31_events); /* should release all sensors and controls */ return 0; }

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Benjamin Herrenschmidt21100.00%1100.00%
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static struct platform_driver wf_rm31_driver = { .probe = wf_rm31_probe, .remove = wf_rm31_remove, .driver = { .name = "windfarm", }, };
static int __init wf_rm31_init(void) { struct device_node *cpu; int i; if (!of_machine_is_compatible("RackMac3,1")) return -ENODEV; /* Count the number of CPU cores */ nr_chips = 0; for_each_node_by_type(cpu, "cpu") ++nr_chips; if (nr_chips > NR_CHIPS) nr_chips = NR_CHIPS; pr_info("windfarm: Initializing for desktop G5 with %d chips\n", nr_chips); /* Get MPU data for each CPU */ for (i = 0; i < nr_chips; i++) { cpu_mpu_data[i] = wf_get_mpu(i); if (!cpu_mpu_data[i]) { pr_err("wf_rm31: Failed to find MPU data for CPU %d\n", i); return -ENXIO; } } #ifdef MODULE request_module("windfarm_fcu_controls"); request_module("windfarm_lm75_sensor"); request_module("windfarm_lm87_sensor"); request_module("windfarm_ad7417_sensor"); request_module("windfarm_max6690_sensor"); request_module("windfarm_cpufreq_clamp"); #endif /* MODULE */ platform_driver_register(&wf_rm31_driver); return 0; }

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Benjamin Herrenschmidt15199.34%150.00%
Wei Yongjun10.66%150.00%
Total152100.00%2100.00%


static void __exit wf_rm31_exit(void) { platform_driver_unregister(&wf_rm31_driver); }

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Benjamin Herrenschmidt15100.00%1100.00%
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module_init(wf_rm31_init); module_exit(wf_rm31_exit); MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); MODULE_DESCRIPTION("Thermal control for Xserve G5"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:windfarm");

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Benjamin Herrenschmidt315599.62%125.00%
Aaro Koskinen90.28%125.00%
Bhumika Goyal20.06%125.00%
Wei Yongjun10.03%125.00%
Total3167100.00%4100.00%
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