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Release 4.14 drivers/macintosh/windfarm_pm91.c

/*
 * Windfarm PowerMac thermal control. SMU based 1 CPU desktop control loops
 *
 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
 *                    <benh@kernel.crashing.org>
 *
 * Released under the term of the GNU GPL v2.
 *
 * The algorithm used is the PID control algorithm, used the same
 * way the published Darwin code does, using the same values that
 * are present in the Darwin 8.2 snapshot property lists (note however
 * that none of the code has been re-used, it's a complete re-implementation
 *
 * The various control loops found in Darwin config file are:
 *
 * PowerMac9,1
 * ===========
 *
 * Has 3 control loops: CPU fans is similar to PowerMac8,1 (though it doesn't
 * try to play with other control loops fans). Drive bay is rather basic PID
 * with one sensor and one fan. Slots area is a bit different as the Darwin
 * driver is supposed to be capable of working in a special "AGP" mode which
 * involves the presence of an AGP sensor and an AGP fan (possibly on the
 * AGP card itself). I can't deal with that special mode as I don't have
 * access to those additional sensor/fans for now (though ultimately, it would
 * be possible to add sensor objects for them) so I'm only implementing the
 * basic PCI slot control loop
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/kmod.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/sections.h>
#include <asm/smu.h>

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


#define VERSION "0.4"


#undef DEBUG

#ifdef DEBUG

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

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

/* define this to force CPU overtemp to 74 degree, useful for testing
 * the overtemp code
 */

#undef HACKED_OVERTEMP

/* Controls & sensors */

static struct wf_sensor	*sensor_cpu_power;

static struct wf_sensor	*sensor_cpu_temp;

static struct wf_sensor	*sensor_hd_temp;

static struct wf_sensor	*sensor_slots_power;

static struct wf_control *fan_cpu_main;

static struct wf_control *fan_cpu_second;

static struct wf_control *fan_cpu_third;

static struct wf_control *fan_hd;

static struct wf_control *fan_slots;

static struct wf_control *cpufreq_clamp;

/* Set to kick the control loop into life */



static int wf_smu_all_controls_ok, wf_smu_all_sensors_ok, wf_smu_started;

static bool wf_smu_overtemp;

/* Failure handling.. could be nicer */

#define FAILURE_FAN		0x01

#define FAILURE_SENSOR		0x02

#define FAILURE_OVERTEMP	0x04


static unsigned int wf_smu_failure_state;


static int wf_smu_readjust, wf_smu_skipping;

/*
 * ****** CPU Fans Control Loop ******
 *
 */



#define WF_SMU_CPU_FANS_INTERVAL	1

#define WF_SMU_CPU_FANS_MAX_HISTORY	16

/* State data used by the cpu fans control loop
 */

struct wf_smu_cpu_fans_state {
	
int			ticks;
	
s32			cpu_setpoint;
	
struct wf_cpu_pid_state	pid;
};


static struct wf_smu_cpu_fans_state *wf_smu_cpu_fans;



/*
 * ****** Drive Fan Control Loop ******
 *
 */


struct wf_smu_drive_fans_state {
	
int			ticks;
	
s32			setpoint;
	
struct wf_pid_state	pid;
};


static struct wf_smu_drive_fans_state *wf_smu_drive_fans;

/*
 * ****** Slots Fan Control Loop ******
 *
 */


struct wf_smu_slots_fans_state {
	
int			ticks;
	
s32			setpoint;
	
struct wf_pid_state	pid;
};


static struct wf_smu_slots_fans_state *wf_smu_slots_fans;

/*
 * ***** Implementation *****
 *
 */



static void wf_smu_create_cpu_fans(void) { struct wf_cpu_pid_param pid_param; const struct smu_sdbp_header *hdr; struct smu_sdbp_cpupiddata *piddata; struct smu_sdbp_fvt *fvt; s32 tmax, tdelta, maxpow, powadj; /* First, locate the PID params in SMU SBD */ hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL); if (hdr == 0) { printk(KERN_WARNING "windfarm: CPU PID fan config not found " "max fan speed\n"); goto fail; } piddata = (struct smu_sdbp_cpupiddata *)&hdr[1]; /* Get the FVT params for operating point 0 (the only supported one * for now) in order to get tmax */ hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL); if (hdr) { fvt = (struct smu_sdbp_fvt *)&hdr[1]; tmax = ((s32)fvt->maxtemp) << 16; } else tmax = 0x5e0000; /* 94 degree default */ /* Alloc & initialize state */ wf_smu_cpu_fans = kmalloc(sizeof(struct wf_smu_cpu_fans_state), GFP_KERNEL); if (wf_smu_cpu_fans == NULL) goto fail; wf_smu_cpu_fans->ticks = 1; /* Fill PID params */ pid_param.interval = WF_SMU_CPU_FANS_INTERVAL; pid_param.history_len = piddata->history_len; if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) { printk(KERN_WARNING "windfarm: History size overflow on " "CPU control loop (%d)\n", piddata->history_len); pid_param.history_len = WF_CPU_PID_MAX_HISTORY; } pid_param.gd = piddata->gd; pid_param.gp = piddata->gp; pid_param.gr = piddata->gr / pid_param.history_len; tdelta = ((s32)piddata->target_temp_delta) << 16; maxpow = ((s32)piddata->max_power) << 16; powadj = ((s32)piddata->power_adj) << 16; pid_param.tmax = tmax; pid_param.ttarget = tmax - tdelta; pid_param.pmaxadj = maxpow - powadj; pid_param.min = wf_control_get_min(fan_cpu_main); pid_param.max = wf_control_get_max(fan_cpu_main); wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param); DBG("wf: CPU Fan control initialized.\n"); DBG(" ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n", FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax), pid_param.min, pid_param.max); return; fail: printk(KERN_WARNING "windfarm: CPU fan config not found\n" "for this machine model, max fan speed\n"); if (cpufreq_clamp) wf_control_set_max(cpufreq_clamp); if (fan_cpu_main) wf_control_set_max(fan_cpu_main); }

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Benjamin Herrenschmidt37499.73%266.67%
Jeremy Kerr10.27%133.33%
Total375100.00%3100.00%


static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state *st) { s32 new_setpoint, temp, power; int rc; if (--st->ticks != 0) { if (wf_smu_readjust) goto readjust; return; } st->ticks = WF_SMU_CPU_FANS_INTERVAL; rc = wf_sensor_get(sensor_cpu_temp, &temp); if (rc) { printk(KERN_WARNING "windfarm: CPU temp sensor error %d\n", rc); wf_smu_failure_state |= FAILURE_SENSOR; return; } rc = wf_sensor_get(sensor_cpu_power, &power); if (rc) { printk(KERN_WARNING "windfarm: CPU power sensor error %d\n", rc); wf_smu_failure_state |= FAILURE_SENSOR; return; } DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n", FIX32TOPRINT(temp), FIX32TOPRINT(power)); #ifdef HACKED_OVERTEMP if (temp > 0x4a0000) wf_smu_failure_state |= FAILURE_OVERTEMP; #else if (temp > st->pid.param.tmax) wf_smu_failure_state |= FAILURE_OVERTEMP; #endif new_setpoint = wf_cpu_pid_run(&st->pid, power, temp); DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint); if (st->cpu_setpoint == new_setpoint) return; st->cpu_setpoint = new_setpoint; readjust: if (fan_cpu_main && wf_smu_failure_state == 0) { rc = wf_control_set(fan_cpu_main, st->cpu_setpoint); if (rc) { printk(KERN_WARNING "windfarm: CPU main fan" " error %d\n", rc); wf_smu_failure_state |= FAILURE_FAN; } } if (fan_cpu_second && wf_smu_failure_state == 0) { rc = wf_control_set(fan_cpu_second, st->cpu_setpoint); if (rc) { printk(KERN_WARNING "windfarm: CPU second fan" " error %d\n", rc); wf_smu_failure_state |= FAILURE_FAN; } } if (fan_cpu_third && wf_smu_failure_state == 0) { rc = wf_control_set(fan_cpu_third, st->cpu_setpoint); if (rc) { printk(KERN_WARNING "windfarm: CPU third fan" " error %d\n", rc); wf_smu_failure_state |= FAILURE_FAN; } } }

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Benjamin Herrenschmidt313100.00%2100.00%
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static void wf_smu_create_drive_fans(void) { struct wf_pid_param param = { .interval = 5, .history_len = 2, .gd = 0x01e00000, .gp = 0x00500000, .gr = 0x00000000, .itarget = 0x00200000, }; /* Alloc & initialize state */ wf_smu_drive_fans = kmalloc(sizeof(struct wf_smu_drive_fans_state), GFP_KERNEL); if (wf_smu_drive_fans == NULL) { printk(KERN_WARNING "windfarm: Memory allocation error" " max fan speed\n"); goto fail; } wf_smu_drive_fans->ticks = 1; /* Fill PID params */ param.additive = (fan_hd->type == WF_CONTROL_RPM_FAN); param.min = wf_control_get_min(fan_hd); param.max = wf_control_get_max(fan_hd); wf_pid_init(&wf_smu_drive_fans->pid, &param); DBG("wf: Drive Fan control initialized.\n"); DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n", FIX32TOPRINT(param.itarget), param.min, param.max); return; fail: if (fan_hd) wf_control_set_max(fan_hd); }

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Benjamin Herrenschmidt161100.00%2100.00%
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static void wf_smu_drive_fans_tick(struct wf_smu_drive_fans_state *st) { s32 new_setpoint, temp; int rc; if (--st->ticks != 0) { if (wf_smu_readjust) goto readjust; return; } st->ticks = st->pid.param.interval; rc = wf_sensor_get(sensor_hd_temp, &temp); if (rc) { printk(KERN_WARNING "windfarm: HD temp sensor error %d\n", rc); wf_smu_failure_state |= FAILURE_SENSOR; return; } DBG("wf_smu: Drive Fans tick ! HD temp: %d.%03d\n", FIX32TOPRINT(temp)); if (temp > (st->pid.param.itarget + 0x50000)) wf_smu_failure_state |= FAILURE_OVERTEMP; new_setpoint = wf_pid_run(&st->pid, temp); DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint); if (st->setpoint == new_setpoint) return; st->setpoint = new_setpoint; readjust: if (fan_hd && wf_smu_failure_state == 0) { rc = wf_control_set(fan_hd, st->setpoint); if (rc) { printk(KERN_WARNING "windfarm: HD fan error %d\n", rc); wf_smu_failure_state |= FAILURE_FAN; } } }

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Benjamin Herrenschmidt187100.00%2100.00%
Total187100.00%2100.00%


static void wf_smu_create_slots_fans(void) { struct wf_pid_param param = { .interval = 1, .history_len = 8, .gd = 0x00000000, .gp = 0x00000000, .gr = 0x00020000, .itarget = 0x00000000 }; /* Alloc & initialize state */ wf_smu_slots_fans = kmalloc(sizeof(struct wf_smu_slots_fans_state), GFP_KERNEL); if (wf_smu_slots_fans == NULL) { printk(KERN_WARNING "windfarm: Memory allocation error" " max fan speed\n"); goto fail; } wf_smu_slots_fans->ticks = 1; /* Fill PID params */ param.additive = (fan_slots->type == WF_CONTROL_RPM_FAN); param.min = wf_control_get_min(fan_slots); param.max = wf_control_get_max(fan_slots); wf_pid_init(&wf_smu_slots_fans->pid, &param); DBG("wf: Slots Fan control initialized.\n"); DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n", FIX32TOPRINT(param.itarget), param.min, param.max); return; fail: if (fan_slots) wf_control_set_max(fan_slots); }

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Benjamin Herrenschmidt161100.00%2100.00%
Total161100.00%2100.00%


static void wf_smu_slots_fans_tick(struct wf_smu_slots_fans_state *st) { s32 new_setpoint, power; int rc; if (--st->ticks != 0) { if (wf_smu_readjust) goto readjust; return; } st->ticks = st->pid.param.interval; rc = wf_sensor_get(sensor_slots_power, &power); if (rc) { printk(KERN_WARNING "windfarm: Slots power sensor error %d\n", rc); wf_smu_failure_state |= FAILURE_SENSOR; return; } DBG("wf_smu: Slots Fans tick ! Slots power: %d.%03d\n", FIX32TOPRINT(power)); #if 0 /* Check what makes a good overtemp condition */ if (power > (st->pid.param.itarget + 0x50000)) wf_smu_failure_state |= FAILURE_OVERTEMP; #endif new_setpoint = wf_pid_run(&st->pid, power); DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint); if (st->setpoint == new_setpoint) return; st->setpoint = new_setpoint; readjust: if (fan_slots && wf_smu_failure_state == 0) { rc = wf_control_set(fan_slots, st->setpoint); if (rc) { printk(KERN_WARNING "windfarm: Slots fan error %d\n", rc); wf_smu_failure_state |= FAILURE_FAN; } } }

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Benjamin Herrenschmidt174100.00%2100.00%
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/* * ****** Setup / Init / Misc ... ****** * */
static void wf_smu_tick(void) { unsigned int last_failure = wf_smu_failure_state; unsigned int new_failure; if (!wf_smu_started) { DBG("wf: creating control loops !\n"); wf_smu_create_drive_fans(); wf_smu_create_slots_fans(); wf_smu_create_cpu_fans(); wf_smu_started = 1; } /* Skipping ticks */ if (wf_smu_skipping && --wf_smu_skipping) return; wf_smu_failure_state = 0; if (wf_smu_drive_fans) wf_smu_drive_fans_tick(wf_smu_drive_fans); if (wf_smu_slots_fans) wf_smu_slots_fans_tick(wf_smu_slots_fans); if (wf_smu_cpu_fans) wf_smu_cpu_fans_tick(wf_smu_cpu_fans); wf_smu_readjust = 0; new_failure = wf_smu_failure_state & ~last_failure; /* If entering failure mode, clamp cpufreq and ramp all * fans to full speed. */ if (wf_smu_failure_state && !last_failure) { if (cpufreq_clamp) wf_control_set_max(cpufreq_clamp); if (fan_cpu_main) wf_control_set_max(fan_cpu_main); if (fan_cpu_second) wf_control_set_max(fan_cpu_second); if (fan_cpu_third) wf_control_set_max(fan_cpu_third); if (fan_hd) wf_control_set_max(fan_hd); if (fan_slots) wf_control_set_max(fan_slots); } /* If leaving failure mode, unclamp cpufreq and readjust * all fans on next iteration */ if (!wf_smu_failure_state && last_failure) { if (cpufreq_clamp) wf_control_set_min(cpufreq_clamp); wf_smu_readjust = 1; } /* Overtemp condition detected, notify and start skipping a couple * ticks to let the temperature go down */ if (new_failure & FAILURE_OVERTEMP) { wf_set_overtemp(); wf_smu_skipping = 2; wf_smu_overtemp = true; } /* We only clear the overtemp condition if overtemp is cleared * _and_ no other failure is present. Since a sensor error will * clear the overtemp condition (can't measure temperature) at * the control loop levels, but we don't want to keep it clear * here in this case */ if (!wf_smu_failure_state && wf_smu_overtemp) { wf_clear_overtemp(); wf_smu_overtemp = false; } }

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Aaro Koskinen135.96%150.00%
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static void wf_smu_new_control(struct wf_control *ct) { if (wf_smu_all_controls_ok) return; if (fan_cpu_main == NULL && !strcmp(ct->name, "cpu-rear-fan-0")) { if (wf_get_control(ct) == 0) fan_cpu_main = ct; } if (fan_cpu_second == NULL && !strcmp(ct->name, "cpu-rear-fan-1")) { if (wf_get_control(ct) == 0) fan_cpu_second = ct; } if (fan_cpu_third == NULL && !strcmp(ct->name, "cpu-front-fan-0")) { if (wf_get_control(ct) == 0) fan_cpu_third = ct; } if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) { if (wf_get_control(ct) == 0) cpufreq_clamp = ct; } if (fan_hd == NULL && !strcmp(ct->name, "drive-bay-fan")) { if (wf_get_control(ct) == 0) fan_hd = ct; } if (fan_slots == NULL && !strcmp(ct->name, "slots-fan")) { if (wf_get_control(ct) == 0) fan_slots = ct; } if (fan_cpu_main && (fan_cpu_second || fan_cpu_third) && fan_hd && fan_slots && cpufreq_clamp) wf_smu_all_controls_ok = 1; }

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Benjamin Herrenschmidt222100.00%1100.00%
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static void wf_smu_new_sensor(struct wf_sensor *sr) { if (wf_smu_all_sensors_ok) return; if (sensor_cpu_power == NULL && !strcmp(sr->name, "cpu-power")) { if (wf_get_sensor(sr) == 0) sensor_cpu_power = sr; } if (sensor_cpu_temp == NULL && !strcmp(sr->name, "cpu-temp")) { if (wf_get_sensor(sr) == 0) sensor_cpu_temp = sr; } if (sensor_hd_temp == NULL && !strcmp(sr->name, "hd-temp")) { if (wf_get_sensor(sr) == 0) sensor_hd_temp = sr; } if (sensor_slots_power == NULL && !strcmp(sr->name, "slots-power")) { if (wf_get_sensor(sr) == 0) sensor_slots_power = sr; } if (sensor_cpu_power && sensor_cpu_temp && sensor_hd_temp && sensor_slots_power) wf_smu_all_sensors_ok = 1; }

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static int wf_smu_notify(struct notifier_block *self, unsigned long event, void *data) { switch(event) { case WF_EVENT_NEW_CONTROL: DBG("wf: new control %s detected\n", ((struct wf_control *)data)->name); wf_smu_new_control(data); wf_smu_readjust = 1; break; case WF_EVENT_NEW_SENSOR: DBG("wf: new sensor %s detected\n", ((struct wf_sensor *)data)->name); wf_smu_new_sensor(data); break; case WF_EVENT_TICK: if (wf_smu_all_controls_ok && wf_smu_all_sensors_ok) wf_smu_tick(); } return 0; }

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Benjamin Herrenschmidt94100.00%1100.00%
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static struct notifier_block wf_smu_events = { .notifier_call = wf_smu_notify, };
static int wf_init_pm(void) { printk(KERN_INFO "windfarm: Initializing for Desktop G5 model\n"); return 0; }

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static int wf_smu_probe(struct platform_device *ddev) { wf_register_client(&wf_smu_events); return 0; }

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static int wf_smu_remove(struct platform_device *ddev) { wf_unregister_client(&wf_smu_events); /* XXX We don't have yet a guarantee that our callback isn't * in progress when returning from wf_unregister_client, so * we add an arbitrary delay. I'll have to fix that in the core */ msleep(1000); /* Release all sensors */ /* One more crappy race: I don't think we have any guarantee here * that the attribute callback won't race with the sensor beeing * disposed of, and I'm not 100% certain what best way to deal * with that except by adding locks all over... I'll do that * eventually but heh, who ever rmmod this module anyway ? */ if (sensor_cpu_power) wf_put_sensor(sensor_cpu_power); if (sensor_cpu_temp) wf_put_sensor(sensor_cpu_temp); if (sensor_hd_temp) wf_put_sensor(sensor_hd_temp); if (sensor_slots_power) wf_put_sensor(sensor_slots_power); /* Release all controls */ if (fan_cpu_main) wf_put_control(fan_cpu_main); if (fan_cpu_second) wf_put_control(fan_cpu_second); if (fan_cpu_third) wf_put_control(fan_cpu_third); if (fan_hd) wf_put_control(fan_hd); if (fan_slots) wf_put_control(fan_slots); if (cpufreq_clamp) wf_put_control(cpufreq_clamp); /* Destroy control loops state structures */ kfree(wf_smu_slots_fans); kfree(wf_smu_drive_fans); kfree(wf_smu_cpu_fans); return 0; }

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Benjamin Herrenschmidt13398.52%266.67%
Julia Lawall21.48%133.33%
Total135100.00%3100.00%

static struct platform_driver wf_smu_driver = { .probe = wf_smu_probe, .remove = wf_smu_remove, .driver = { .name = "windfarm", }, };
static int __init wf_smu_init(void) { int rc = -ENODEV; if (of_machine_is_compatible("PowerMac9,1")) rc = wf_init_pm(); if (rc == 0) { #ifdef MODULE request_module("windfarm_smu_controls"); request_module("windfarm_smu_sensors"); request_module("windfarm_lm75_sensor"); request_module("windfarm_cpufreq_clamp"); #endif /* MODULE */ platform_driver_register(&wf_smu_driver); } return rc; }

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Benjamin Herrenschmidt6998.57%375.00%
Grant C. Likely11.43%125.00%
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static void __exit wf_smu_exit(void) { platform_driver_unregister(&wf_smu_driver); }

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module_init(wf_smu_init); module_exit(wf_smu_exit); MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); MODULE_DESCRIPTION("Thermal control logic for PowerMac9,1"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:windfarm");

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Benjamin Herrenschmidt262399.02%444.44%
Aaro Koskinen170.64%111.11%
Kay Sievers50.19%111.11%
Julia Lawall20.08%111.11%
Jeremy Kerr10.04%111.11%
Grant C. Likely10.04%111.11%
Total2649100.00%9100.00%
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