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Release 4.11 drivers/net/ethernet/freescale/fec_ptp.c

/*
 * Fast Ethernet Controller (ENET) PTP driver for MX6x.
 *
 * Copyright (C) 2012 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/phy.h>
#include <linux/fec.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_net.h>

#include "fec.h"

/* FEC 1588 register bits */

#define FEC_T_CTRL_SLAVE                0x00002000

#define FEC_T_CTRL_CAPTURE              0x00000800

#define FEC_T_CTRL_RESTART              0x00000200

#define FEC_T_CTRL_PERIOD_RST           0x00000030

#define FEC_T_CTRL_PERIOD_EN		0x00000010

#define FEC_T_CTRL_ENABLE               0x00000001


#define FEC_T_INC_MASK                  0x0000007f

#define FEC_T_INC_OFFSET                0

#define FEC_T_INC_CORR_MASK             0x00007f00

#define FEC_T_INC_CORR_OFFSET           8


#define FEC_T_CTRL_PINPER		0x00000080

#define FEC_T_TF0_MASK			0x00000001

#define FEC_T_TF0_OFFSET		0

#define FEC_T_TF1_MASK			0x00000002

#define FEC_T_TF1_OFFSET		1

#define FEC_T_TF2_MASK			0x00000004

#define FEC_T_TF2_OFFSET		2

#define FEC_T_TF3_MASK			0x00000008

#define FEC_T_TF3_OFFSET		3

#define FEC_T_TDRE_MASK			0x00000001

#define FEC_T_TDRE_OFFSET		0

#define FEC_T_TMODE_MASK		0x0000003C

#define FEC_T_TMODE_OFFSET		2

#define FEC_T_TIE_MASK			0x00000040

#define FEC_T_TIE_OFFSET		6

#define FEC_T_TF_MASK			0x00000080

#define FEC_T_TF_OFFSET			7


#define FEC_ATIME_CTRL		0x400

#define FEC_ATIME		0x404

#define FEC_ATIME_EVT_OFFSET	0x408

#define FEC_ATIME_EVT_PERIOD	0x40c

#define FEC_ATIME_CORR		0x410

#define FEC_ATIME_INC		0x414

#define FEC_TS_TIMESTAMP	0x418


#define FEC_TGSR		0x604

#define FEC_TCSR(n)		(0x608 + n * 0x08)

#define FEC_TCCR(n)		(0x60C + n * 0x08)

#define MAX_TIMER_CHANNEL	3

#define FEC_TMODE_TOGGLE	0x05

#define FEC_HIGH_PULSE		0x0F


#define FEC_CC_MULT	(1 << 31)

#define FEC_COUNTER_PERIOD	(1 << 31)

#define PPS_OUPUT_RELOAD_PERIOD	NSEC_PER_SEC

#define FEC_CHANNLE_0		0

#define DEFAULT_PPS_CHANNEL	FEC_CHANNLE_0

/**
 * fec_ptp_enable_pps
 * @fep: the fec_enet_private structure handle
 * @enable: enable the channel pps output
 *
 * This function enble the PPS ouput on the timer channel.
 */

static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable) { unsigned long flags; u32 val, tempval; int inc; struct timespec64 ts; u64 ns; val = 0; if (!(fep->hwts_tx_en || fep->hwts_rx_en)) { dev_err(&fep->pdev->dev, "No ptp stack is running\n"); return -EINVAL; } if (fep->pps_enable == enable) return 0; fep->pps_channel = DEFAULT_PPS_CHANNEL; fep->reload_period = PPS_OUPUT_RELOAD_PERIOD; inc = fep->ptp_inc; spin_lock_irqsave(&fep->tmreg_lock, flags); if (enable) { /* clear capture or output compare interrupt status if have. */ writel(FEC_T_TF_MASK, fep->hwp + FEC_TCSR(fep->pps_channel)); /* It is recommended to double check the TMODE field in the * TCSR register to be cleared before the first compare counter * is written into TCCR register. Just add a double check. */ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel)); do { val &= ~(FEC_T_TMODE_MASK); writel(val, fep->hwp + FEC_TCSR(fep->pps_channel)); val = readl(fep->hwp + FEC_TCSR(fep->pps_channel)); } while (val & FEC_T_TMODE_MASK); /* Dummy read counter to update the counter */ timecounter_read(&fep->tc); /* We want to find the first compare event in the next * second point. So we need to know what the ptp time * is now and how many nanoseconds is ahead to get next second. * The remaining nanosecond ahead before the next second would be * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds * to current timer would be next second. */ tempval = readl(fep->hwp + FEC_ATIME_CTRL); tempval |= FEC_T_CTRL_CAPTURE; writel(tempval, fep->hwp + FEC_ATIME_CTRL); tempval = readl(fep->hwp + FEC_ATIME); /* Convert the ptp local counter to 1588 timestamp */ ns = timecounter_cyc2time(&fep->tc, tempval); ts = ns_to_timespec64(ns); /* The tempval is less than 3 seconds, and so val is less than * 4 seconds. No overflow for 32bit calculation. */ val = NSEC_PER_SEC - (u32)ts.tv_nsec + tempval; /* Need to consider the situation that the current time is * very close to the second point, which means NSEC_PER_SEC * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer * is still running when we calculate the first compare event, it is * possible that the remaining nanoseonds run out before the compare * counter is calculated and written into TCCR register. To avoid * this possibility, we will set the compare event to be the next * of next second. The current setting is 31-bit timer and wrap * around over 2 seconds. So it is okay to set the next of next * seond for the timer. */ val += NSEC_PER_SEC; /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current * ptp counter, which maybe cause 32-bit wrap. Since the * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second. * We can ensure the wrap will not cause issue. If the offset * is bigger than fep->cc.mask would be a error. */ val &= fep->cc.mask; writel(val, fep->hwp + FEC_TCCR(fep->pps_channel)); /* Calculate the second the compare event timestamp */ fep->next_counter = (val + fep->reload_period) & fep->cc.mask; /* * Enable compare event when overflow */ val = readl(fep->hwp + FEC_ATIME_CTRL); val |= FEC_T_CTRL_PINPER; writel(val, fep->hwp + FEC_ATIME_CTRL); /* Compare channel setting. */ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel)); val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET); val &= ~(1 << FEC_T_TDRE_OFFSET); val &= ~(FEC_T_TMODE_MASK); val |= (FEC_HIGH_PULSE << FEC_T_TMODE_OFFSET); writel(val, fep->hwp + FEC_TCSR(fep->pps_channel)); /* Write the second compare event timestamp and calculate * the third timestamp. Refer the TCCR register detail in the spec. */ writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel)); fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask; } else { writel(0, fep->hwp + FEC_TCSR(fep->pps_channel)); } fep->pps_enable = enable; spin_unlock_irqrestore(&fep->tmreg_lock, flags); return 0; }

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Luwei Zhou49699.40%133.33%
Arnd Bergmann20.40%133.33%
Joe Perches10.20%133.33%
Total499100.00%3100.00%

/** * fec_ptp_read - read raw cycle counter (to be used by time counter) * @cc: the cyclecounter structure * * this function reads the cyclecounter registers and is called by the * cyclecounter structure used to construct a ns counter from the * arbitrary fixed point registers */
static u64 fec_ptp_read(const struct cyclecounter *cc) { struct fec_enet_private *fep = container_of(cc, struct fec_enet_private, cc); const struct platform_device_id *id_entry = platform_get_device_id(fep->pdev); u32 tempval; tempval = readl(fep->hwp + FEC_ATIME_CTRL); tempval |= FEC_T_CTRL_CAPTURE; writel(tempval, fep->hwp + FEC_ATIME_CTRL); if (id_entry->driver_data & FEC_QUIRK_BUG_CAPTURE) udelay(1); return readl(fep->hwp + FEC_ATIME); }

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PersonTokensPropCommitsCommitProp
Frank Li6570.65%133.33%
Nimrod Andy2628.26%133.33%
Thomas Gleixner11.09%133.33%
Total92100.00%3100.00%

/** * fec_ptp_start_cyclecounter - create the cycle counter from hw * @ndev: network device * * this function initializes the timecounter and cyclecounter * structures for use in generated a ns counter from the arbitrary * fixed point cycles registers in the hardware. */
void fec_ptp_start_cyclecounter(struct net_device *ndev) { struct fec_enet_private *fep = netdev_priv(ndev); unsigned long flags; int inc; inc = 1000000000 / fep->cycle_speed; /* grab the ptp lock */ spin_lock_irqsave(&fep->tmreg_lock, flags); /* 1ns counter */ writel(inc << FEC_T_INC_OFFSET, fep->hwp + FEC_ATIME_INC); /* use 31-bit timer counter */ writel(FEC_COUNTER_PERIOD, fep->hwp + FEC_ATIME_EVT_PERIOD); writel(FEC_T_CTRL_ENABLE | FEC_T_CTRL_PERIOD_RST, fep->hwp + FEC_ATIME_CTRL); memset(&fep->cc, 0, sizeof(fep->cc)); fep->cc.read = fec_ptp_read; fep->cc.mask = CLOCKSOURCE_MASK(31); fep->cc.shift = 31; fep->cc.mult = FEC_CC_MULT; /* reset the ns time counter */ timecounter_init(&fep->tc, &fep->cc, ktime_to_ns(ktime_get_real())); spin_unlock_irqrestore(&fep->tmreg_lock, flags); }

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Frank Li16297.01%266.67%
Luwei Zhou52.99%133.33%
Total167100.00%3100.00%

/** * fec_ptp_adjfreq - adjust ptp cycle frequency * @ptp: the ptp clock structure * @ppb: parts per billion adjustment from base * * Adjust the frequency of the ptp cycle counter by the * indicated ppb from the base frequency. * * Because ENET hardware frequency adjust is complex, * using software method to do that. */
static int fec_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) { unsigned long flags; int neg_adj = 0; u32 i, tmp; u32 corr_inc, corr_period; u32 corr_ns; u64 lhs, rhs; struct fec_enet_private *fep = container_of(ptp, struct fec_enet_private, ptp_caps); if (ppb == 0) return 0; if (ppb < 0) { ppb = -ppb; neg_adj = 1; } /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC; * Try to find the corr_inc between 1 to fep->ptp_inc to * meet adjustment requirement. */ lhs = NSEC_PER_SEC; rhs = (u64)ppb * (u64)fep->ptp_inc; for (i = 1; i <= fep->ptp_inc; i++) { if (lhs >= rhs) { corr_inc = i; corr_period = div_u64(lhs, rhs); break; } lhs += NSEC_PER_SEC; } /* Not found? Set it to high value - double speed * correct in every clock step. */ if (i > fep->ptp_inc) { corr_inc = fep->ptp_inc; corr_period = 1; } if (neg_adj) corr_ns = fep->ptp_inc - corr_inc; else corr_ns = fep->ptp_inc + corr_inc; spin_lock_irqsave(&fep->tmreg_lock, flags); tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK; tmp |= corr_ns << FEC_T_INC_CORR_OFFSET; writel(tmp, fep->hwp + FEC_ATIME_INC); corr_period = corr_period > 1 ? corr_period - 1 : corr_period; writel(corr_period, fep->hwp + FEC_ATIME_CORR); /* dummy read to update the timer. */ timecounter_read(&fep->tc); spin_unlock_irqrestore(&fep->tmreg_lock, flags); return 0; }

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Luwei Zhou15958.67%125.00%
Frank Li10036.90%250.00%
Fugang Duan124.43%125.00%
Total271100.00%4100.00%

/** * fec_ptp_adjtime * @ptp: the ptp clock structure * @delta: offset to adjust the cycle counter by * * adjust the timer by resetting the timecounter structure. */
static int fec_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) { struct fec_enet_private *fep = container_of(ptp, struct fec_enet_private, ptp_caps); unsigned long flags; spin_lock_irqsave(&fep->tmreg_lock, flags); timecounter_adjtime(&fep->tc, delta); spin_unlock_irqrestore(&fep->tmreg_lock, flags); return 0; }

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Frank Li6395.45%133.33%
Richard Cochran23.03%133.33%
Luwei Zhou11.52%133.33%
Total66100.00%3100.00%

/** * fec_ptp_gettime * @ptp: the ptp clock structure * @ts: timespec structure to hold the current time value * * read the timecounter and return the correct value on ns, * after converting it into a struct timespec. */
static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) { struct fec_enet_private *adapter = container_of(ptp, struct fec_enet_private, ptp_caps); u64 ns; unsigned long flags; spin_lock_irqsave(&adapter->tmreg_lock, flags); ns = timecounter_read(&adapter->tc); spin_unlock_irqrestore(&adapter->tmreg_lock, flags); *ts = ns_to_timespec64(ns); return 0; }

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Frank Li7696.20%133.33%
Richard Cochran33.80%266.67%
Total79100.00%3100.00%

/** * fec_ptp_settime * @ptp: the ptp clock structure * @ts: the timespec containing the new time for the cycle counter * * reset the timecounter to use a new base value instead of the kernel * wall timer value. */
static int fec_ptp_settime(struct ptp_clock_info *ptp, const struct timespec64 *ts) { struct fec_enet_private *fep = container_of(ptp, struct fec_enet_private, ptp_caps); u64 ns; unsigned long flags; u32 counter; mutex_lock(&fep->ptp_clk_mutex); /* Check the ptp clock */ if (!fep->ptp_clk_on) { mutex_unlock(&fep->ptp_clk_mutex); return -EINVAL; } ns = timespec64_to_ns(ts); /* Get the timer value based on timestamp. * Update the counter with the masked value. */ counter = ns & fep->cc.mask; spin_lock_irqsave(&fep->tmreg_lock, flags); writel(counter, fep->hwp + FEC_ATIME); timecounter_init(&fep->tc, &fep->cc, ns); spin_unlock_irqrestore(&fep->tmreg_lock, flags); mutex_unlock(&fep->ptp_clk_mutex); return 0; }

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Frank Li8054.42%120.00%
Nimrod Andy3825.85%120.00%
Luwei Zhou2517.01%120.00%
Richard Cochran42.72%240.00%
Total147100.00%5100.00%

/** * fec_ptp_enable * @ptp: the ptp clock structure * @rq: the requested feature to change * @on: whether to enable or disable the feature * */
static int fec_ptp_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *rq, int on) { struct fec_enet_private *fep = container_of(ptp, struct fec_enet_private, ptp_caps); int ret = 0; if (rq->type == PTP_CLK_REQ_PPS) { ret = fec_ptp_enable_pps(fep, on); return ret; } return -EOPNOTSUPP; }

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Luwei Zhou4264.62%150.00%
Frank Li2335.38%150.00%
Total65100.00%2100.00%

/** * fec_ptp_hwtstamp_ioctl - control hardware time stamping * @ndev: pointer to net_device * @ifreq: ioctl data * @cmd: particular ioctl requested */
int fec_ptp_set(struct net_device *ndev, struct ifreq *ifr) { struct fec_enet_private *fep = netdev_priv(ndev); struct hwtstamp_config config; if (copy_from_user(&config, ifr->ifr_data, sizeof(config))) return -EFAULT; /* reserved for future extensions */ if (config.flags) return -EINVAL; switch (config.tx_type) { case HWTSTAMP_TX_OFF: fep->hwts_tx_en = 0; break; case HWTSTAMP_TX_ON: fep->hwts_tx_en = 1; break; default: return -ERANGE; } switch (config.rx_filter) { case HWTSTAMP_FILTER_NONE: if (fep->hwts_rx_en) fep->hwts_rx_en = 0; config.rx_filter = HWTSTAMP_FILTER_NONE; break; default: fep->hwts_rx_en = 1; config.rx_filter = HWTSTAMP_FILTER_ALL; break; } return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ? -EFAULT : 0; }

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Frank Li15899.37%150.00%
Ben Hutchings10.63%150.00%
Total159100.00%2100.00%


int fec_ptp_get(struct net_device *ndev, struct ifreq *ifr) { struct fec_enet_private *fep = netdev_priv(ndev); struct hwtstamp_config config; config.flags = 0; config.tx_type = fep->hwts_tx_en ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF; config.rx_filter = (fep->hwts_rx_en ? HWTSTAMP_FILTER_ALL : HWTSTAMP_FILTER_NONE); return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ? -EFAULT : 0; }

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Ben Hutchings82100.00%1100.00%
Total82100.00%1100.00%

/** * fec_time_keep - call timecounter_read every second to avoid timer overrun * because ENET just support 32bit counter, will timeout in 4s */
static void fec_time_keep(struct work_struct *work) { struct delayed_work *dwork = to_delayed_work(work); struct fec_enet_private *fep = container_of(dwork, struct fec_enet_private, time_keep); u64 ns; unsigned long flags; mutex_lock(&fep->ptp_clk_mutex); if (fep->ptp_clk_on) { spin_lock_irqsave(&fep->tmreg_lock, flags); ns = timecounter_read(&fep->tc); spin_unlock_irqrestore(&fep->tmreg_lock, flags); } mutex_unlock(&fep->ptp_clk_mutex); schedule_delayed_work(&fep->time_keep, HZ); }

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Frank Li6157.01%150.00%
Nimrod Andy4642.99%150.00%
Total107100.00%2100.00%

/** * fec_ptp_init * @ndev: The FEC network adapter * * This function performs the required steps for enabling ptp * support. If ptp support has already been loaded it simply calls the * cyclecounter init routine and exits. */
void fec_ptp_init(struct platform_device *pdev) { struct net_device *ndev = platform_get_drvdata(pdev); struct fec_enet_private *fep = netdev_priv(ndev); fep->ptp_caps.owner = THIS_MODULE; snprintf(fep->ptp_caps.name, 16, "fec ptp"); fep->ptp_caps.max_adj = 250000000; fep->ptp_caps.n_alarm = 0; fep->ptp_caps.n_ext_ts = 0; fep->ptp_caps.n_per_out = 0; fep->ptp_caps.n_pins = 0; fep->ptp_caps.pps = 1; fep->ptp_caps.adjfreq = fec_ptp_adjfreq; fep->ptp_caps.adjtime = fec_ptp_adjtime; fep->ptp_caps.gettime64 = fec_ptp_gettime; fep->ptp_caps.settime64 = fec_ptp_settime; fep->ptp_caps.enable = fec_ptp_enable; fep->cycle_speed = clk_get_rate(fep->clk_ptp); fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed; spin_lock_init(&fep->tmreg_lock); fec_ptp_start_cyclecounter(ndev); INIT_DELAYED_WORK(&fep->time_keep, fec_time_keep); fep->ptp_clock = ptp_clock_register(&fep->ptp_caps, &pdev->dev); if (IS_ERR(fep->ptp_clock)) { fep->ptp_clock = NULL; pr_err("ptp_clock_register failed\n"); } schedule_delayed_work(&fep->time_keep, HZ); }

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Frank Li18981.47%225.00%
Nimrod Andy125.17%112.50%
Luwei Zhou114.74%225.00%
Fabio Estevam104.31%112.50%
Richard Cochran104.31%225.00%
Total232100.00%8100.00%


void fec_ptp_stop(struct platform_device *pdev) { struct net_device *ndev = platform_get_drvdata(pdev); struct fec_enet_private *fep = netdev_priv(ndev); cancel_delayed_work_sync(&fep->time_keep); if (fep->ptp_clock) ptp_clock_unregister(fep->ptp_clock); }

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Lucas Stach51100.00%1100.00%
Total51100.00%1100.00%

/** * fec_ptp_check_pps_event * @fep: the fec_enet_private structure handle * * This function check the pps event and reload the timer compare counter. */
uint fec_ptp_check_pps_event(struct fec_enet_private *fep) { u32 val; u8 channel = fep->pps_channel; struct ptp_clock_event event; val = readl(fep->hwp + FEC_TCSR(channel)); if (val & FEC_T_TF_MASK) { /* Write the next next compare(not the next according the spec) * value to the register */ writel(fep->next_counter, fep->hwp + FEC_TCCR(channel)); do { writel(val, fep->hwp + FEC_TCSR(channel)); } while (readl(fep->hwp + FEC_TCSR(channel)) & FEC_T_TF_MASK); /* Update the counter; */ fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask; event.type = PTP_CLOCK_PPS; ptp_clock_event(fep->ptp_clock, &event); return 1; } return 0; }

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Luwei Zhou140100.00%1100.00%
Total140100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Frank Li114246.71%315.00%
Luwei Zhou99540.70%315.00%
Nimrod Andy1224.99%210.00%
Ben Hutchings833.39%15.00%
Lucas Stach512.09%15.00%
Richard Cochran190.78%420.00%
Fugang Duan120.49%15.00%
Fabio Estevam100.41%15.00%
Joe Perches80.33%210.00%
Arnd Bergmann20.08%15.00%
Thomas Gleixner10.04%15.00%
Total2445100.00%20100.00%
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