723 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
			
		
		
	
	
			723 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
/* can-calc-bit-timing.c: Calculate CAN bit timing parameters
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 *
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 * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com>
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 *
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 * Derived from:
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 *   can_baud.c - CAN baudrate calculation
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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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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * any later version.
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 */
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#include <errno.h>
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#include <getopt.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <linux/types.h>
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/* seems not to be defined in errno.h */
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#ifndef ENOTSUPP
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#define ENOTSUPP	524	/* Operation is not supported */
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#endif
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/* useful defines */
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#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
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#define do_div(a,b) a = (a) / (b)
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#define abs(x) ({				\
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		long __x = (x);			\
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		(__x < 0) ? -__x : __x;		\
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	})
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/**
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 * clamp - return a value clamped to a given range with strict typechecking
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 * @val: current value
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 * @min: minimum allowable value
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 * @max: maximum allowable value
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 *
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 * This macro does strict typechecking of min/max to make sure they are of the
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 * same type as val.  See the unnecessary pointer comparisons.
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 */
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#define clamp(val, min, max) ({			\
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	typeof(val) __val = (val);		\
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	typeof(min) __min = (min);		\
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	typeof(max) __max = (max);		\
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	(void) (&__val == &__min);		\
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	(void) (&__val == &__max);		\
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	__val = __val < __min ? __min: __val;	\
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	__val > __max ? __max: __val; })
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/* we don't want to see these prints */
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#define dev_err(dev, format, arg...)	do { } while (0)
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#define dev_warn(dev, format, arg...)	do { } while (0)
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/* define in-kernel-types */
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typedef __u64 u64;
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typedef __u32 u32;
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/*
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 * CAN bit-timing parameters
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 *
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 * For futher information, please read chapter "8 BIT TIMING
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 * REQUIREMENTS" of the "Bosch CAN Specification version 2.0"
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 * at http://www.semiconductors.bosch.de/pdf/can2spec.pdf.
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 */
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struct can_bittiming {
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	__u32 bitrate;		/* Bit-rate in bits/second */
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	__u32 sample_point;	/* Sample point in one-tenth of a percent */
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	__u32 tq;		/* Time quanta (TQ) in nanoseconds */
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	__u32 prop_seg;		/* Propagation segment in TQs */
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	__u32 phase_seg1;	/* Phase buffer segment 1 in TQs */
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	__u32 phase_seg2;	/* Phase buffer segment 2 in TQs */
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	__u32 sjw;		/* Synchronisation jump width in TQs */
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	__u32 brp;		/* Bit-rate prescaler */
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};
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/*
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 * CAN harware-dependent bit-timing constant
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 *
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 * Used for calculating and checking bit-timing parameters
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 */
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struct can_bittiming_const {
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	char name[16];		/* Name of the CAN controller hardware */
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	__u32 tseg1_min;	/* Time segement 1 = prop_seg + phase_seg1 */
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	__u32 tseg1_max;
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	__u32 tseg2_min;	/* Time segement 2 = phase_seg2 */
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	__u32 tseg2_max;
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	__u32 sjw_max;		/* Synchronisation jump width */
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	__u32 brp_min;		/* Bit-rate prescaler */
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	__u32 brp_max;
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	__u32 brp_inc;
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	/* added for can-calc-bit-timing utility */
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	__u32 ref_clk;		/* CAN system clock frequency in Hz */
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	void (*printf_btr)(struct can_bittiming *bt, int hdr);
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};
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/*
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 * CAN clock parameters
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 */
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struct can_clock {
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	__u32 freq;		/* CAN system clock frequency in Hz */
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};
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/*
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 * minimal structs, just enough to be source level compatible
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 */
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struct can_priv {
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	const struct can_bittiming_const *bittiming_const;
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	struct can_clock clock;
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};
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struct net_device {
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	struct can_priv	priv;
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};
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static inline void *netdev_priv(const struct net_device *dev)
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{
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	return (void *)&dev->priv;
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}
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static void print_usage(char* cmd)
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{
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	printf("Usage: %s [options] [<CAN-contoller-name>]\n"
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	       "\tOptions:\n"
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	       "\t-q           : don't print header line\n"
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	       "\t-l           : list all support CAN controller names\n"
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	       "\t-b <bitrate> : bit-rate in bits/sec\n"
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	       "\t-s <samp_pt> : sample-point in one-tenth of a percent\n"
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	       "\t               or 0 for CIA recommended sample points\n"
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	       "\t-c <clock>   : real CAN system clock in Hz\n",
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	       cmd);
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	exit(EXIT_FAILURE);
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}
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static void printf_btr_sja1000(struct can_bittiming *bt, int hdr)
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{
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	uint8_t btr0, btr1;
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	if (hdr) {
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		printf("BTR0 BTR1");
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	} else {
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		btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
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		btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
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			(((bt->phase_seg2 - 1) & 0x7) << 4);
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		printf("0x%02x 0x%02x", btr0, btr1);
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	}
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}
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static void printf_btr_at91(struct can_bittiming *bt, int hdr)
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{
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	if (hdr) {
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		printf("%10s", "CAN_BR");
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	} else {
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		uint32_t br = ((bt->phase_seg2 - 1) |
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			       ((bt->phase_seg1 - 1) << 4) |
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			       ((bt->prop_seg - 1) << 8) |
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			       ((bt->sjw - 1) << 12) |
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			       ((bt->brp - 1) << 16));
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		printf("0x%08x", br);
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	}
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}
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static void printf_btr_flexcan(struct can_bittiming *bt, int hdr)
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{
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	if (hdr) {
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		printf("%10s", "CAN_CTRL");
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	} else {
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		uint32_t ctrl = (((bt->brp        - 1) << 24) |
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				 ((bt->sjw        - 1) << 22) |
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				 ((bt->phase_seg1 - 1) << 19) |
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				 ((bt->phase_seg2 - 1) << 16) |
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				 ((bt->prop_seg   - 1) <<  0));
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		printf("0x%08x", ctrl);
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	}
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}
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static void printf_btr_mcp251x(struct can_bittiming *bt, int hdr)
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{
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	uint8_t cnf1, cnf2, cnf3;
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	if (hdr) {
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		printf("CNF1 CNF2 CNF3");
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	} else {
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		cnf1 = ((bt->sjw - 1) << 6) | (bt->brp - 1);
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		cnf2 = 0x80 | ((bt->phase_seg1 - 1) << 3) | (bt->prop_seg - 1);
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		cnf3 = bt->phase_seg2 - 1;
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		printf("0x%02x 0x%02x 0x%02x", cnf1, cnf2, cnf3);
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	}
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}
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static void printf_btr_ti_hecc(struct can_bittiming *bt, int hdr)
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{
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	if (hdr) {
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		printf("%10s", "CANBTC");
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	} else {
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		uint32_t can_btc;
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		can_btc = (bt->phase_seg2 - 1) & 0x7;
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		can_btc |= ((bt->phase_seg1 + bt->prop_seg - 1)
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			    & 0xF) << 3;
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		can_btc |= ((bt->sjw - 1) & 0x3) << 8;
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		can_btc |= ((bt->brp - 1) & 0xFF) << 16;
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		printf("0x%08x", can_btc);
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	}
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}
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static struct can_bittiming_const can_calc_consts[] = {
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	{
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		.name = "sja1000",
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		.tseg1_min = 1,
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		.tseg1_max = 16,
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		.tseg2_min = 1,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 8000000,
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "mscan",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 32000000,
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "mscan",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 33000000,
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "mscan",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 33300000,
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "mscan",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 33333333,
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "mscan",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 1,
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		.brp_max = 64,
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		.brp_inc = 1,
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		.ref_clk = 66660000,	/* mpc5121 */
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		.printf_btr = printf_btr_sja1000,
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	},
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	{
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		.name = "at91",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 2,
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		.brp_max = 128,
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		.brp_inc = 1,
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		.ref_clk = 100000000,
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		.printf_btr = printf_btr_at91,
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	},
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	{
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		.name = "at91",
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		.tseg1_min = 4,
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		.tseg1_max = 16,
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		.tseg2_min = 2,
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		.tseg2_max = 8,
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		.sjw_max = 4,
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		.brp_min = 2,
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						|
		.brp_max = 128,
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		.brp_inc = 1,
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						|
 | 
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		/* real world clock as found on the ronetix PM9263 */
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		.ref_clk = 99532800,
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		.printf_btr = printf_btr_at91,
 | 
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	},
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	{
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		.name = "flexcan",
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		.tseg1_min = 4,
 | 
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		.tseg1_max = 16,
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						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 256,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 24000000,	/* mx28 */
 | 
						|
		.printf_btr = printf_btr_flexcan,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "flexcan",
 | 
						|
		.tseg1_min = 4,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 256,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 49875000,
 | 
						|
		.printf_btr = printf_btr_flexcan,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "flexcan",
 | 
						|
		.tseg1_min = 4,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 256,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 66000000,
 | 
						|
		.printf_btr = printf_btr_flexcan,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "flexcan",
 | 
						|
		.tseg1_min = 4,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 256,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 66500000,
 | 
						|
		.printf_btr = printf_btr_flexcan,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "mcp251x",
 | 
						|
		.tseg1_min = 3,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 64,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 8000000,
 | 
						|
		.printf_btr = printf_btr_mcp251x,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "mcp251x",
 | 
						|
		.tseg1_min = 3,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 2,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 64,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 16000000,
 | 
						|
		.printf_btr = printf_btr_mcp251x,
 | 
						|
	},
 | 
						|
	{
 | 
						|
		.name = "ti_hecc",
 | 
						|
		.tseg1_min = 1,
 | 
						|
		.tseg1_max = 16,
 | 
						|
		.tseg2_min = 1,
 | 
						|
		.tseg2_max = 8,
 | 
						|
		.sjw_max = 4,
 | 
						|
		.brp_min = 1,
 | 
						|
		.brp_max = 256,
 | 
						|
		.brp_inc = 1,
 | 
						|
 | 
						|
		.ref_clk = 13000000,
 | 
						|
		.printf_btr = printf_btr_ti_hecc,
 | 
						|
	}
 | 
						|
};
 | 
						|
 | 
						|
static long common_bitrates[] = {
 | 
						|
	1000000,
 | 
						|
	800000,
 | 
						|
	500000,
 | 
						|
	250000,
 | 
						|
	125000,
 | 
						|
	100000,
 | 
						|
	50000,
 | 
						|
	20000,
 | 
						|
	10000,
 | 
						|
};
 | 
						|
 | 
						|
#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
 | 
						|
 | 
						|
static int can_update_spt(const struct can_bittiming_const *btc,
 | 
						|
			  int sampl_pt, int tseg, int *tseg1, int *tseg2)
 | 
						|
{
 | 
						|
	*tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000;
 | 
						|
	if (*tseg2 < btc->tseg2_min)
 | 
						|
		*tseg2 = btc->tseg2_min;
 | 
						|
	if (*tseg2 > btc->tseg2_max)
 | 
						|
		*tseg2 = btc->tseg2_max;
 | 
						|
	*tseg1 = tseg - *tseg2;
 | 
						|
	if (*tseg1 > btc->tseg1_max) {
 | 
						|
		*tseg1 = btc->tseg1_max;
 | 
						|
		*tseg2 = tseg - *tseg1;
 | 
						|
	}
 | 
						|
	return 1000 * (tseg + 1 - *tseg2) / (tseg + 1);
 | 
						|
}
 | 
						|
 | 
						|
static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt)
 | 
						|
{
 | 
						|
	struct can_priv *priv = netdev_priv(dev);
 | 
						|
	const struct can_bittiming_const *btc = priv->bittiming_const;
 | 
						|
	long rate = 0;
 | 
						|
	long best_error = 1000000000, error = 0;
 | 
						|
	int best_tseg = 0, best_brp = 0, brp = 0;
 | 
						|
	int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0;
 | 
						|
	int spt_error = 1000, spt = 0, sampl_pt;
 | 
						|
	u64 v64;
 | 
						|
 | 
						|
	if (!priv->bittiming_const)
 | 
						|
		return -ENOTSUPP;
 | 
						|
 | 
						|
	/* 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) {
 | 
						|
			dev_err(dev->dev.parent,
 | 
						|
				"bitrate error %ld.%ld%% too high\n",
 | 
						|
				error / 10, error % 10);
 | 
						|
			return -EDOM;
 | 
						|
		} else {
 | 
						|
			dev_warn(dev->dev.parent, "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;
 | 
						|
	bt->sjw = 1;
 | 
						|
	bt->brp = best_brp;
 | 
						|
 | 
						|
	/* real bit-rate */
 | 
						|
	bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1));
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static __u32 get_cia_sample_point(__u32 bitrate)
 | 
						|
{
 | 
						|
	__u32 sampl_pt;
 | 
						|
 | 
						|
	if (bitrate > 800000)
 | 
						|
		sampl_pt = 750;
 | 
						|
	else if (bitrate > 500000)
 | 
						|
		sampl_pt = 800;
 | 
						|
	else
 | 
						|
		sampl_pt = 875;
 | 
						|
 | 
						|
	return sampl_pt;
 | 
						|
}
 | 
						|
 | 
						|
static void print_bit_timing(const struct can_bittiming_const *btc,
 | 
						|
			     __u32 bitrate, __u32 sample_point, __u32 ref_clk,
 | 
						|
			     int quiet)
 | 
						|
{
 | 
						|
	struct net_device dev = {
 | 
						|
		.priv.bittiming_const = btc,
 | 
						|
		.priv.clock.freq = ref_clk,
 | 
						|
	};
 | 
						|
	struct can_bittiming bt = {
 | 
						|
		.bitrate = bitrate,
 | 
						|
		.sample_point = sample_point,
 | 
						|
	};
 | 
						|
	long rate_error, spt_error;
 | 
						|
 | 
						|
	if (!quiet) {
 | 
						|
		printf("Bit timing parameters for %s with %.6f MHz ref clock\n"
 | 
						|
		       "nominal                                 real Bitrt   nom  real SampP\n"
 | 
						|
		       "Bitrate TQ[ns] PrS PhS1 PhS2 SJW BRP Bitrate Error SampP SampP Error ",
 | 
						|
		       btc->name,
 | 
						|
		       ref_clk / 1000000.0);
 | 
						|
 | 
						|
		btc->printf_btr(&bt, 1);
 | 
						|
		printf("\n");
 | 
						|
	}
 | 
						|
 | 
						|
	if (can_calc_bittiming(&dev, &bt)) {
 | 
						|
		printf("%7d ***bitrate not possible***\n", bitrate);
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	/* get nominal sample point */
 | 
						|
	if (!sample_point)
 | 
						|
		sample_point = get_cia_sample_point(bitrate);
 | 
						|
 | 
						|
	rate_error = abs((__s32)(bitrate - bt.bitrate));
 | 
						|
	spt_error = abs((__s32)(sample_point - bt.sample_point));
 | 
						|
 | 
						|
	printf("%7d "
 | 
						|
	       "%6d %3d %4d %4d "
 | 
						|
	       "%3d %3d "
 | 
						|
	       "%7d %4.1f%% "
 | 
						|
	       "%4.1f%% %4.1f%% %4.1f%% ",
 | 
						|
	       bitrate,
 | 
						|
	       bt.tq, bt.prop_seg, bt.phase_seg1, bt.phase_seg2,
 | 
						|
	       bt.sjw, bt.brp,
 | 
						|
 | 
						|
	       bt.bitrate,
 | 
						|
	       100.0 * rate_error / bitrate,
 | 
						|
 | 
						|
	       sample_point / 10.0,
 | 
						|
	       bt.sample_point / 10.0,
 | 
						|
	       100.0 * spt_error / sample_point);
 | 
						|
 | 
						|
	btc->printf_btr(&bt, 0);
 | 
						|
	printf("\n");
 | 
						|
}
 | 
						|
 | 
						|
static void do_list(void)
 | 
						|
{
 | 
						|
	unsigned int i;
 | 
						|
 | 
						|
	for (i = 0; i < ARRAY_SIZE(can_calc_consts); i++)
 | 
						|
		printf("%s\n", can_calc_consts[i].name);
 | 
						|
}
 | 
						|
 | 
						|
int main(int argc, char *argv[])
 | 
						|
{
 | 
						|
	__u32 bitrate = 0;
 | 
						|
	__u32 opt_ref_clk = 0, ref_clk;
 | 
						|
	int sampl_pt = 0;
 | 
						|
	int quiet = 0;
 | 
						|
	int list = 0;
 | 
						|
	char *name = NULL;
 | 
						|
	unsigned int i, j;
 | 
						|
	int opt, found = 0;
 | 
						|
 | 
						|
	const struct can_bittiming_const *btc = NULL;
 | 
						|
 | 
						|
	while ((opt = getopt(argc, argv, "b:c:lps:")) != -1) {
 | 
						|
		switch (opt) {
 | 
						|
		case 'b':
 | 
						|
			bitrate = atoi(optarg);
 | 
						|
			break;
 | 
						|
 | 
						|
		case 'c':
 | 
						|
			opt_ref_clk = atoi(optarg);
 | 
						|
			break;
 | 
						|
 | 
						|
		case 'l':
 | 
						|
			list = 1;
 | 
						|
			break;
 | 
						|
 | 
						|
		case 'q':
 | 
						|
			quiet = 1;
 | 
						|
			break;
 | 
						|
 | 
						|
		case 's':
 | 
						|
			sampl_pt = atoi(optarg);
 | 
						|
			break;
 | 
						|
 | 
						|
		default:
 | 
						|
			print_usage(argv[0]);
 | 
						|
			break;
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	if (argc > optind + 1)
 | 
						|
		print_usage(argv[0]);
 | 
						|
 | 
						|
	if (argc == optind + 1)
 | 
						|
		name = argv[optind];
 | 
						|
 | 
						|
	if (list) {
 | 
						|
		do_list();
 | 
						|
		exit(EXIT_SUCCESS);
 | 
						|
	}
 | 
						|
 | 
						|
	if (sampl_pt && (sampl_pt >= 1000 || sampl_pt < 100))
 | 
						|
		print_usage(argv[0]);
 | 
						|
 | 
						|
	for (i = 0; i < ARRAY_SIZE(can_calc_consts); i++) {
 | 
						|
		if (name && strcmp(can_calc_consts[i].name, name))
 | 
						|
			continue;
 | 
						|
 | 
						|
		found = 1;
 | 
						|
		btc = &can_calc_consts[i];
 | 
						|
 | 
						|
		if (opt_ref_clk)
 | 
						|
			ref_clk = opt_ref_clk;
 | 
						|
		else
 | 
						|
			ref_clk = btc->ref_clk;
 | 
						|
 | 
						|
		if (bitrate) {
 | 
						|
			print_bit_timing(btc, bitrate, sampl_pt, ref_clk, quiet);
 | 
						|
		} else {
 | 
						|
			for (j = 0; j < ARRAY_SIZE(common_bitrates); j++)
 | 
						|
				print_bit_timing(btc, common_bitrates[j],
 | 
						|
						 sampl_pt, ref_clk, j);
 | 
						|
		}
 | 
						|
		printf("\n");
 | 
						|
	}
 | 
						|
 | 
						|
	if (!found) {
 | 
						|
		printf("error: unknown CAN controller '%s', try one of these:\n\n", name);
 | 
						|
		do_list();
 | 
						|
		exit(EXIT_FAILURE);
 | 
						|
	}
 | 
						|
 | 
						|
	exit(EXIT_SUCCESS);
 | 
						|
}
 |