can-calc-bit-timing: move algorithms into separate files
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>pull/372/head
Marc Kleine-Budde
parent
a7062893da
commit
ee2f48f33b
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@ -5,6 +5,8 @@ AM_CPPFLAGS = \
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-I$(top_builddir)/include \
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$(linux_CFLAGS)
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EXTRA_DIST =
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# link every app against libcan, it's static so it wouldn't hurt
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LDADD = \
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libcan.la
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@ -42,6 +44,10 @@ libj1939_la_SOURCES = \
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can_calc_bit_timing_SOURCES = \
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calc-bit-timing/can-calc-bit-timing.c
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EXTRA_DIST += \
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calc-bit-timing/can-calc-bit-timing-v3_18.c \
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calc-bit-timing/can-calc-bit-timing-v4_8.c
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mcp251xfd_dump_SOURCES = \
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mcp251xfd/mcp251xfd-dev-coredump.c \
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mcp251xfd/mcp251xfd-dump-userspace.h \
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@ -90,7 +96,7 @@ j1939spy_LDADD = libj1939.la
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j1939sr_LDADD = libj1939.la
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testj1939_LDADD = libj1939.la
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EXTRA_DIST = \
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EXTRA_DIST += \
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.travis.yml \
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Android.mk \
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README.md \
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@ -0,0 +1,155 @@
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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* imported from v3.18-rc1~52^2~248^2~1
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*
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*/
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/*
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* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
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* Copyright (C) 2006 Andrey Volkov, Varma Electronics
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* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the version 2 of the GNU General Public License
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* as published by the Free Software Foundation
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
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* Copyright 2005 Stanislav Marek
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* email: pisa@cmp.felk.cvut.cz
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*
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* Calculates proper bit-timing parameters for a specified bit-rate
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* and sample-point, which can then be used to set the bit-timing
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* registers of the CAN controller. You can find more information
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* in the header file linux/can/netlink.h.
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*/
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static int can_update_spt(const struct can_bittiming_const *btc,
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int sampl_pt, int tseg, int *tseg1, int *tseg2)
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{
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*tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000;
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if (*tseg2 < btc->tseg2_min)
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*tseg2 = btc->tseg2_min;
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if (*tseg2 > btc->tseg2_max)
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*tseg2 = btc->tseg2_max;
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*tseg1 = tseg - *tseg2;
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if (*tseg1 > btc->tseg1_max) {
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*tseg1 = btc->tseg1_max;
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*tseg2 = tseg - *tseg1;
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}
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return 1000 * (tseg + 1 - *tseg2) / (tseg + 1);
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}
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static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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long best_error = 1000000000, error = 0;
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int best_tseg = 0, best_brp = 0, brp = 0;
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int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0;
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int spt_error = 1000, spt = 0, sampl_pt;
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long rate;
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u64 v64;
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/* Use CIA recommended sample points */
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if (bt->sample_point) {
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sampl_pt = bt->sample_point;
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} else {
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if (bt->bitrate > 800000)
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sampl_pt = 750;
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else if (bt->bitrate > 500000)
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sampl_pt = 800;
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else
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sampl_pt = 875;
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}
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/* tseg even = round down, odd = round up */
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for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
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tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
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tsegall = 1 + tseg / 2;
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/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
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brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
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/* chose brp step which is possible in system */
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brp = (brp / btc->brp_inc) * btc->brp_inc;
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if ((brp < btc->brp_min) || (brp > btc->brp_max))
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continue;
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rate = priv->clock.freq / (brp * tsegall);
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error = bt->bitrate - rate;
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/* tseg brp biterror */
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if (error < 0)
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error = -error;
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if (error > best_error)
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continue;
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best_error = error;
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if (error == 0) {
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spt = can_update_spt(btc, sampl_pt, tseg / 2,
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&tseg1, &tseg2);
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error = sampl_pt - spt;
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if (error < 0)
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error = -error;
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if (error > spt_error)
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continue;
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spt_error = error;
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}
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best_tseg = tseg / 2;
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best_brp = brp;
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if (error == 0)
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break;
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}
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if (best_error) {
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/* Error in one-tenth of a percent */
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error = (best_error * 1000) / bt->bitrate;
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if (error > CAN_CALC_MAX_ERROR) {
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netdev_err(dev,
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"bitrate error %ld.%ld%% too high\n",
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error / 10, error % 10);
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return -EDOM;
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} else {
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netdev_warn(dev, "bitrate error %ld.%ld%%\n",
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error / 10, error % 10);
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}
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}
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/* real sample point */
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bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg,
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&tseg1, &tseg2);
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v64 = (u64)best_brp * 1000000000UL;
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do_div(v64, priv->clock.freq);
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bt->tq = (u32)v64;
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bt->prop_seg = tseg1 / 2;
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bt->phase_seg1 = tseg1 - bt->prop_seg;
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bt->phase_seg2 = tseg2;
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/* check for sjw user settings */
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if (!bt->sjw || !btc->sjw_max)
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bt->sjw = 1;
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else {
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/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
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if (bt->sjw > btc->sjw_max)
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bt->sjw = btc->sjw_max;
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/* bt->sjw must not be higher than tseg2 */
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if (tseg2 < bt->sjw)
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bt->sjw = tseg2;
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}
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bt->brp = best_brp;
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/* real bit-rate */
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bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1));
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return 0;
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}
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@ -0,0 +1,181 @@
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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* imported from v4.8-rc1~140^2~304^2~11
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*
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*/
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/*
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* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
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* Copyright (C) 2006 Andrey Volkov, Varma Electronics
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* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the version 2 of the GNU General Public License
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* as published by the Free Software Foundation
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
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* Copyright 2005 Stanislav Marek
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* email: pisa@cmp.felk.cvut.cz
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*
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* Calculates proper bit-timing parameters for a specified bit-rate
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* and sample-point, which can then be used to set the bit-timing
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* registers of the CAN controller. You can find more information
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* in the header file linux/can/netlink.h.
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*/
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static int can_update_spt(const struct can_bittiming_const *btc,
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unsigned int spt_nominal, unsigned int tseg,
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unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
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unsigned int *spt_error_ptr)
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{
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unsigned int spt_error, best_spt_error = UINT_MAX;
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unsigned int spt, best_spt = 0;
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unsigned int tseg1, tseg2;
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int i;
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for (i = 0; i <= 1; i++) {
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tseg2 = tseg + CAN_CALC_SYNC_SEG - (spt_nominal * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i;
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tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
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tseg1 = tseg - tseg2;
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if (tseg1 > btc->tseg1_max) {
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tseg1 = btc->tseg1_max;
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tseg2 = tseg - tseg1;
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}
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spt = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
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spt_error = abs(spt_nominal - spt);
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if ((spt <= spt_nominal) && (spt_error < best_spt_error)) {
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best_spt = spt;
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best_spt_error = spt_error;
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*tseg1_ptr = tseg1;
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*tseg2_ptr = tseg2;
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}
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}
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if (spt_error_ptr)
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*spt_error_ptr = best_spt_error;
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return best_spt;
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}
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static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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unsigned int rate; /* current bitrate */
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unsigned int rate_error; /* difference between current and nominal value */
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unsigned int best_rate_error = UINT_MAX;
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unsigned int spt_error; /* difference between current and nominal value */
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unsigned int best_spt_error = UINT_MAX;
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unsigned int spt_nominal; /* nominal sample point */
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unsigned int best_tseg = 0; /* current best value for tseg */
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unsigned int best_brp = 0; /* current best value for brp */
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unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
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u64 v64;
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/* Use CiA recommended sample points */
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if (bt->sample_point) {
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spt_nominal = bt->sample_point;
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} else {
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if (bt->bitrate > 800000)
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spt_nominal = 750;
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else if (bt->bitrate > 500000)
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spt_nominal = 800;
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else
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spt_nominal = 875;
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}
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/* tseg even = round down, odd = round up */
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for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
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tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
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tsegall = CAN_CALC_SYNC_SEG + tseg / 2;
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/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
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brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
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/* choose brp step which is possible in system */
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brp = (brp / btc->brp_inc) * btc->brp_inc;
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if ((brp < btc->brp_min) || (brp > btc->brp_max))
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continue;
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rate = priv->clock.freq / (brp * tsegall);
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rate_error = abs(bt->bitrate - rate);
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/* tseg brp biterror */
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if (rate_error > best_rate_error)
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continue;
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/* reset sample point error if we have a better bitrate */
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if (rate_error < best_rate_error)
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best_spt_error = UINT_MAX;
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can_update_spt(btc, spt_nominal, tseg / 2, &tseg1, &tseg2, &spt_error);
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if (spt_error > best_spt_error)
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continue;
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best_spt_error = spt_error;
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best_rate_error = rate_error;
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best_tseg = tseg / 2;
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best_brp = brp;
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if (rate_error == 0 && spt_error == 0)
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break;
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}
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if (best_rate_error) {
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/* Error in one-tenth of a percent */
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rate_error = (best_rate_error * 1000) / bt->bitrate;
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if (rate_error > CAN_CALC_MAX_ERROR) {
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netdev_err(dev,
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"bitrate error %ld.%ld%% too high\n",
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rate_error / 10, rate_error % 10);
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return -EDOM;
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}
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netdev_warn(dev, "bitrate error %ld.%ld%%\n",
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rate_error / 10, rate_error % 10);
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}
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/* real sample point */
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bt->sample_point = can_update_spt(btc, spt_nominal, best_tseg,
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&tseg1, &tseg2, NULL);
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v64 = (u64)best_brp * 1000 * 1000 * 1000;
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do_div(v64, priv->clock.freq);
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bt->tq = (u32)v64;
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bt->prop_seg = tseg1 / 2;
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bt->phase_seg1 = tseg1 - bt->prop_seg;
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bt->phase_seg2 = tseg2;
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/* check for sjw user settings */
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if (!bt->sjw || !btc->sjw_max) {
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bt->sjw = 1;
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} else {
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/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
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if (bt->sjw > btc->sjw_max)
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bt->sjw = btc->sjw_max;
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/* bt->sjw must not be higher than tseg2 */
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if (tseg2 < bt->sjw)
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bt->sjw = tseg2;
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}
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bt->brp = best_brp;
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/* real bit-rate */
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bt->bitrate = priv->clock.freq / (bt->brp * (CAN_CALC_SYNC_SEG + tseg1 + tseg2));
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return 0;
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}
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@ -1176,303 +1176,17 @@ static const unsigned int common_data_bitrates[] = {
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#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
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#define CAN_CALC_SYNC_SEG 1
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/*
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* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
|
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
|
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* Copyright 2005 Stanislav Marek
|
||||
* email: pisa@cmp.felk.cvut.cz
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*
|
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* Calculates proper bit-timing parameters for a specified bit-rate
|
||||
* and sample-point, which can then be used to set the bit-timing
|
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* registers of the CAN controller. You can find more information
|
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* in the header file linux/can/netlink.h.
|
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*/
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/*
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* imported from v3.18-rc1~52^2~248^2~1
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*
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* b25a437206ed can: dev: remove unused variable from can_calc_bittiming() function
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*/
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#undef can_calc_bittiming
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#undef can_update_spt
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#define can_calc_bittiming can_calc_bittiming_v3_18
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#define can_update_spt can_update_spt_v3_18
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static int can_update_spt(const struct can_bittiming_const *btc,
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int sampl_pt, int tseg, int *tseg1, int *tseg2)
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{
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*tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000;
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if (*tseg2 < btc->tseg2_min)
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*tseg2 = btc->tseg2_min;
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if (*tseg2 > btc->tseg2_max)
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*tseg2 = btc->tseg2_max;
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*tseg1 = tseg - *tseg2;
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if (*tseg1 > btc->tseg1_max) {
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*tseg1 = btc->tseg1_max;
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*tseg2 = tseg - *tseg1;
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}
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return 1000 * (tseg + 1 - *tseg2) / (tseg + 1);
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}
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static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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long best_error = 1000000000, error = 0;
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int best_tseg = 0, best_brp = 0, brp = 0;
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int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0;
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int spt_error = 1000, spt = 0, sampl_pt;
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long rate;
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u64 v64;
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/* Use CIA recommended sample points */
|
||||
if (bt->sample_point) {
|
||||
sampl_pt = bt->sample_point;
|
||||
} else {
|
||||
if (bt->bitrate > 800000)
|
||||
sampl_pt = 750;
|
||||
else if (bt->bitrate > 500000)
|
||||
sampl_pt = 800;
|
||||
else
|
||||
sampl_pt = 875;
|
||||
}
|
||||
|
||||
/* tseg even = round down, odd = round up */
|
||||
for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
|
||||
tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
|
||||
tsegall = 1 + tseg / 2;
|
||||
/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
|
||||
brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
|
||||
/* chose brp step which is possible in system */
|
||||
brp = (brp / btc->brp_inc) * btc->brp_inc;
|
||||
if ((brp < btc->brp_min) || (brp > btc->brp_max))
|
||||
continue;
|
||||
rate = priv->clock.freq / (brp * tsegall);
|
||||
error = bt->bitrate - rate;
|
||||
/* tseg brp biterror */
|
||||
if (error < 0)
|
||||
error = -error;
|
||||
if (error > best_error)
|
||||
continue;
|
||||
best_error = error;
|
||||
if (error == 0) {
|
||||
spt = can_update_spt(btc, sampl_pt, tseg / 2,
|
||||
&tseg1, &tseg2);
|
||||
error = sampl_pt - spt;
|
||||
if (error < 0)
|
||||
error = -error;
|
||||
if (error > spt_error)
|
||||
continue;
|
||||
spt_error = error;
|
||||
}
|
||||
best_tseg = tseg / 2;
|
||||
best_brp = brp;
|
||||
if (error == 0)
|
||||
break;
|
||||
}
|
||||
|
||||
if (best_error) {
|
||||
/* Error in one-tenth of a percent */
|
||||
error = (best_error * 1000) / bt->bitrate;
|
||||
if (error > CAN_CALC_MAX_ERROR) {
|
||||
netdev_err(dev,
|
||||
"bitrate error %ld.%ld%% too high\n",
|
||||
error / 10, error % 10);
|
||||
return -EDOM;
|
||||
} else {
|
||||
netdev_warn(dev, "bitrate error %ld.%ld%%\n",
|
||||
error / 10, error % 10);
|
||||
}
|
||||
}
|
||||
|
||||
/* real sample point */
|
||||
bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg,
|
||||
&tseg1, &tseg2);
|
||||
|
||||
v64 = (u64)best_brp * 1000000000UL;
|
||||
do_div(v64, priv->clock.freq);
|
||||
bt->tq = (u32)v64;
|
||||
bt->prop_seg = tseg1 / 2;
|
||||
bt->phase_seg1 = tseg1 - bt->prop_seg;
|
||||
bt->phase_seg2 = tseg2;
|
||||
|
||||
/* check for sjw user settings */
|
||||
if (!bt->sjw || !btc->sjw_max)
|
||||
bt->sjw = 1;
|
||||
else {
|
||||
/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
|
||||
if (bt->sjw > btc->sjw_max)
|
||||
bt->sjw = btc->sjw_max;
|
||||
/* bt->sjw must not be higher than tseg2 */
|
||||
if (tseg2 < bt->sjw)
|
||||
bt->sjw = tseg2;
|
||||
}
|
||||
|
||||
bt->brp = best_brp;
|
||||
/* real bit-rate */
|
||||
bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1));
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* imported from v4.8-rc1~140^2~304^2~11
|
||||
*
|
||||
* 7da29f97d6c8 can: dev: can-calc-bit-timing(): better sample point calculation
|
||||
*/
|
||||
#define can_calc_bittiming can_calc_bittiming_v3_18
|
||||
#include "can-calc-bit-timing-v3_18.c"
|
||||
#undef can_update_spt
|
||||
#undef can_calc_bittiming
|
||||
#define can_update_spt can_update_spt_v4_8
|
||||
|
||||
#define can_update_sample_point can_update_sample_point_v4_8
|
||||
#define can_calc_bittiming can_calc_bittiming_v4_8
|
||||
|
||||
static int can_update_spt(const struct can_bittiming_const *btc,
|
||||
unsigned int spt_nominal, unsigned int tseg,
|
||||
unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
|
||||
unsigned int *spt_error_ptr)
|
||||
{
|
||||
unsigned int spt_error, best_spt_error = UINT_MAX;
|
||||
unsigned int spt, best_spt = 0;
|
||||
unsigned int tseg1, tseg2;
|
||||
int i;
|
||||
|
||||
for (i = 0; i <= 1; i++) {
|
||||
tseg2 = tseg + CAN_CALC_SYNC_SEG - (spt_nominal * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i;
|
||||
tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
|
||||
tseg1 = tseg - tseg2;
|
||||
if (tseg1 > btc->tseg1_max) {
|
||||
tseg1 = btc->tseg1_max;
|
||||
tseg2 = tseg - tseg1;
|
||||
}
|
||||
|
||||
spt = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
|
||||
spt_error = abs(spt_nominal - spt);
|
||||
|
||||
if ((spt <= spt_nominal) && (spt_error < best_spt_error)) {
|
||||
best_spt = spt;
|
||||
best_spt_error = spt_error;
|
||||
*tseg1_ptr = tseg1;
|
||||
*tseg2_ptr = tseg2;
|
||||
}
|
||||
}
|
||||
|
||||
if (spt_error_ptr)
|
||||
*spt_error_ptr = best_spt_error;
|
||||
|
||||
return best_spt;
|
||||
}
|
||||
|
||||
static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
||||
const struct can_bittiming_const *btc)
|
||||
{
|
||||
struct can_priv *priv = netdev_priv(dev);
|
||||
unsigned int rate; /* current bitrate */
|
||||
unsigned int rate_error; /* difference between current and nominal value */
|
||||
unsigned int best_rate_error = UINT_MAX;
|
||||
unsigned int spt_error; /* difference between current and nominal value */
|
||||
unsigned int best_spt_error = UINT_MAX;
|
||||
unsigned int spt_nominal; /* nominal sample point */
|
||||
unsigned int best_tseg = 0; /* current best value for tseg */
|
||||
unsigned int best_brp = 0; /* current best value for brp */
|
||||
unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
|
||||
u64 v64;
|
||||
|
||||
/* Use CiA recommended sample points */
|
||||
if (bt->sample_point) {
|
||||
spt_nominal = bt->sample_point;
|
||||
} else {
|
||||
if (bt->bitrate > 800000)
|
||||
spt_nominal = 750;
|
||||
else if (bt->bitrate > 500000)
|
||||
spt_nominal = 800;
|
||||
else
|
||||
spt_nominal = 875;
|
||||
}
|
||||
|
||||
/* tseg even = round down, odd = round up */
|
||||
for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
|
||||
tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
|
||||
tsegall = CAN_CALC_SYNC_SEG + tseg / 2;
|
||||
|
||||
/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
|
||||
brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
|
||||
|
||||
/* choose brp step which is possible in system */
|
||||
brp = (brp / btc->brp_inc) * btc->brp_inc;
|
||||
if ((brp < btc->brp_min) || (brp > btc->brp_max))
|
||||
continue;
|
||||
|
||||
rate = priv->clock.freq / (brp * tsegall);
|
||||
rate_error = abs(bt->bitrate - rate);
|
||||
|
||||
/* tseg brp biterror */
|
||||
if (rate_error > best_rate_error)
|
||||
continue;
|
||||
|
||||
/* reset sample point error if we have a better bitrate */
|
||||
if (rate_error < best_rate_error)
|
||||
best_spt_error = UINT_MAX;
|
||||
|
||||
can_update_spt(btc, spt_nominal, tseg / 2, &tseg1, &tseg2, &spt_error);
|
||||
if (spt_error > best_spt_error)
|
||||
continue;
|
||||
|
||||
best_spt_error = spt_error;
|
||||
best_rate_error = rate_error;
|
||||
best_tseg = tseg / 2;
|
||||
best_brp = brp;
|
||||
|
||||
if (rate_error == 0 && spt_error == 0)
|
||||
break;
|
||||
}
|
||||
|
||||
if (best_rate_error) {
|
||||
/* Error in one-tenth of a percent */
|
||||
rate_error = (best_rate_error * 1000) / bt->bitrate;
|
||||
if (rate_error > CAN_CALC_MAX_ERROR) {
|
||||
netdev_err(dev,
|
||||
"bitrate error %ld.%ld%% too high\n",
|
||||
rate_error / 10, rate_error % 10);
|
||||
return -EDOM;
|
||||
}
|
||||
netdev_warn(dev, "bitrate error %ld.%ld%%\n",
|
||||
rate_error / 10, rate_error % 10);
|
||||
}
|
||||
|
||||
/* real sample point */
|
||||
bt->sample_point = can_update_spt(btc, spt_nominal, best_tseg,
|
||||
&tseg1, &tseg2, NULL);
|
||||
|
||||
v64 = (u64)best_brp * 1000 * 1000 * 1000;
|
||||
do_div(v64, priv->clock.freq);
|
||||
bt->tq = (u32)v64;
|
||||
bt->prop_seg = tseg1 / 2;
|
||||
bt->phase_seg1 = tseg1 - bt->prop_seg;
|
||||
bt->phase_seg2 = tseg2;
|
||||
|
||||
/* check for sjw user settings */
|
||||
if (!bt->sjw || !btc->sjw_max) {
|
||||
bt->sjw = 1;
|
||||
} else {
|
||||
/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
|
||||
if (bt->sjw > btc->sjw_max)
|
||||
bt->sjw = btc->sjw_max;
|
||||
/* bt->sjw must not be higher than tseg2 */
|
||||
if (tseg2 < bt->sjw)
|
||||
bt->sjw = tseg2;
|
||||
}
|
||||
|
||||
bt->brp = best_brp;
|
||||
|
||||
/* real bit-rate */
|
||||
bt->bitrate = priv->clock.freq / (bt->brp * (CAN_CALC_SYNC_SEG + tseg1 + tseg2));
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
#include "can-calc-bit-timing-v4_8.c"
|
||||
#undef can_update_sample_point
|
||||
#undef can_calc_bittiming
|
||||
#undef can_update_spt
|
||||
|
||||
static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
||||
const struct can_bittiming_const *btc)
|
||||
|
|
|
|||
Loading…
Reference in New Issue