struct calc_bittiming_const {
struct can_bittiming_const bittiming_const;
- __u32 ref_clk; /* CAN system clock frequency in Hz */
+ __u32 ref_clk[16]; /* CAN system clock frequency in Hz */
void (*printf_btr)(struct can_bittiming *bt, bool hdr);
};
.brp_max = 64,
.brp_inc = 1,
},
- .ref_clk = 8000000,
- .printf_btr = printf_btr_sja1000,
- }, {
- .bittiming_const = {
- .name = "mscan",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 64,
- .brp_inc = 1,
- },
- .ref_clk = 32000000,
- .printf_btr = printf_btr_sja1000,
- }, {
- .bittiming_const = {
- .name = "mscan",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 64,
- .brp_inc = 1,
- },
- .ref_clk = 33000000,
- .printf_btr = printf_btr_sja1000,
- }, {
- .bittiming_const = {
- .name = "mscan",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 64,
- .brp_inc = 1,
- },
- .ref_clk = 33300000,
- .printf_btr = printf_btr_sja1000,
- }, {
- .bittiming_const = {
- .name = "mscan",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 64,
- .brp_inc = 1,
+ .ref_clk = {
+ 8000000,
},
- .ref_clk = 33333333,
.printf_btr = printf_btr_sja1000,
}, {
.bittiming_const = {
.brp_max = 64,
.brp_inc = 1,
},
- .ref_clk = 66660000, /* mpc5121 */
- .printf_btr = printf_btr_sja1000,
- }, {
- .bittiming_const = {
- .name = "mscan",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 64,
- .brp_inc = 1,
+ .ref_clk = {
+ 32000000,
+ 33000000,
+ 33300000,
+ 33333333,
+ 66660000, /* mpc5121 */
+ 66666666, /* mpc5121 */
},
- .ref_clk = 66666666, /* mpc5121 */
.printf_btr = printf_btr_sja1000,
}, {
.bittiming_const = {
.brp_max = 128,
.brp_inc = 1,
},
- .ref_clk = 100000000,
- .printf_btr = printf_btr_at91,
- }, {
- .bittiming_const = {
- .name = "at91",
- .tseg1_min = 4,
- .tseg1_max = 16,
- .tseg2_min = 2,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 2,
- .brp_max = 128,
- .brp_inc = 1,
+ .ref_clk = {
+ 99532800, /* ronetix PM9263 */
+ 100000000,
},
- /* real world clock as found on the ronetix PM9263 */
- .ref_clk = 99532800,
.printf_btr = printf_btr_at91,
}, {
.bittiming_const = {
.brp_max = 256,
.brp_inc = 1,
},
- .ref_clk = 24000000, /* mx28 */
- .printf_btr = printf_btr_flexcan,
- }, {
- .bittiming_const = {
- .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 = 30000000, /* mx6 */
- .printf_btr = printf_btr_flexcan,
- }, {
- .bittiming_const = {
- .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,
- }, {
- .bittiming_const = {
- .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,
- }, {
- .bittiming_const = {
- .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 = {
+ 24000000, /* mx28 */
+ 30000000, /* mx6 */
+ 49875000,
+ 66000000,
+ 66500000,
+ 66666666,
+ 83368421, /* vybrid */
},
- .ref_clk = 66500000,
.printf_btr = printf_btr_flexcan,
- }, {
- .bittiming_const = {
- .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 = 66666666,
- .printf_btr = printf_btr_flexcan,
- }, {
- .bittiming_const = {
- .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 = 83368421,
- .printf_btr = printf_btr_flexcan, /* vybrid */
}, {
.bittiming_const = {
.name = "mcp251x",
.brp_max = 64,
.brp_inc = 1,
},
- .ref_clk = 8000000,
- .printf_btr = printf_btr_mcp251x,
- }, {
- .bittiming_const = {
- .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,
+ 16000000,
},
- .ref_clk = 16000000,
.printf_btr = printf_btr_mcp251x,
}, {
.bittiming_const = {
.brp_max = 256,
.brp_inc = 1,
},
- .ref_clk = 13000000,
+ .ref_clk = {
+ 13000000,
+ },
.printf_btr = printf_btr_ti_hecc,
}, {
.bittiming_const = {
.brp_max = 1024,
.brp_inc = 1,
},
- .ref_clk = 65000000,
+ .ref_clk = {
+ 65000000,
+ },
.printf_btr = printf_btr_rcar_can,
},
};
* in the header file linux/can/netlink.h.
*/
static int can_update_spt(const struct can_bittiming_const *btc,
- unsigned int spt_target, unsigned int tseg,
+ unsigned int spt_nominal, unsigned int tseg,
unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
unsigned int *spt_error_ptr)
{
int i;
for (i = 0; i <= 1; i++) {
- tseg2 = tseg + CAN_CALC_SYNC_SEG - (spt_target * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - 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) {
}
spt = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
- spt_error = abs(spt_target - spt);
+ spt_error = abs(spt_nominal - spt);
- if ((spt <= spt_target) && (spt_error < best_spt_error)) {
+ if ((spt <= spt_nominal) && (spt_error < best_spt_error)) {
best_spt = spt;
best_spt_error = spt_error;
*tseg1_ptr = tseg1;
{
struct can_priv *priv = netdev_priv(dev);
unsigned int rate; /* current bitrate */
- unsigned int rate_error; /* difference between current and target value */
+ 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 target value */
+ unsigned int spt_error; /* difference between current and nominal value */
unsigned int best_spt_error = UINT_MAX;
- unsigned int spt_target; /* target sample point */
+ 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, tseg2;
/* Use CiA recommended sample points */
if (bt->sample_point) {
- spt_target = bt->sample_point;
+ spt_nominal = bt->sample_point;
} else {
if (bt->bitrate > 800000)
- spt_target = 750;
+ spt_nominal = 750;
else if (bt->bitrate > 500000)
- spt_target = 800;
+ spt_nominal = 800;
else
- spt_target = 875;
+ spt_nominal = 875;
}
/* tseg even = round down, odd = round up */
if (rate_error < best_rate_error)
best_spt_error = UINT_MAX;
- can_update_spt(btc, spt_target, tseg / 2, &tseg1, &tseg2, &spt_error);
+ can_update_spt(btc, spt_nominal, tseg / 2, &tseg1, &tseg2, &spt_error);
if (spt_error > best_spt_error)
continue;
}
/* real sample point */
- bt->sample_point = can_update_spt(btc, spt_target, best_tseg,
+ bt->sample_point = can_update_spt(btc, spt_nominal, best_tseg,
&tseg1, &tseg2, NULL);
v64 = (u64)best_brp * 1000 * 1000 * 1000;
}
static void print_bit_timing(const struct calc_bittiming_const *btc,
- __u32 bitrate, __u32 sample_point, __u32 ref_clk,
+ __u32 bitrate_nominal, __u32 spt_nominal, __u32 ref_clk,
bool quiet)
{
struct net_device dev = {
.priv.clock.freq = ref_clk,
};
struct can_bittiming bt = {
- .bitrate = bitrate,
- .sample_point = sample_point,
+ .bitrate = bitrate_nominal,
+ .sample_point = spt_nominal,
};
long rate_error, spt_error;
}
if (can_calc_bittiming(&dev, &bt, &btc->bittiming_const)) {
- printf("%7d ***bitrate not possible***\n", bitrate);
+ printf("%7d ***bitrate not possible***\n", bitrate_nominal);
return;
}
/* get nominal sample point */
- if (!sample_point)
- sample_point = get_cia_sample_point(bitrate);
+ if (!spt_nominal)
+ spt_nominal = get_cia_sample_point(bitrate_nominal);
- rate_error = abs(bitrate - bt.bitrate);
- spt_error = abs(sample_point - bt.sample_point);
+ rate_error = abs(bitrate_nominal - bt.bitrate);
+ spt_error = abs(spt_nominal - bt.sample_point);
printf("%7d "
"%6d %3d %4d %4d "
"%3d %3d "
"%7d %4.1f%% "
"%4.1f%% %4.1f%% %4.1f%% ",
- bitrate,
+ bitrate_nominal,
bt.tq, bt.prop_seg, bt.phase_seg1, bt.phase_seg2,
bt.sjw, bt.brp,
bt.bitrate,
- 100.0 * rate_error / bitrate,
+ 100.0 * rate_error / bitrate_nominal,
- sample_point / 10.0,
+ spt_nominal / 10.0,
bt.sample_point / 10.0,
- 100.0 * spt_error / sample_point);
+ 100.0 * spt_error / spt_nominal);
btc->printf_btr(&bt, false);
printf("\n");
int main(int argc, char *argv[])
{
- __u32 bitrate = 0;
+ __u32 bitrate_nominal = 0;
__u32 opt_ref_clk = 0, ref_clk;
- unsigned int spt_target = 0;
+ unsigned int spt_nominal = 0;
bool quiet = false, list = false, found = false;
char *name = NULL;
- unsigned int i, j;
+ unsigned int i, j, k;
int opt;
- const struct calc_bittiming_const *btc = NULL;
+ const struct calc_bittiming_const *btc;
while ((opt = getopt(argc, argv, "b:c:lps:")) != -1) {
switch (opt) {
case 'b':
- bitrate = atoi(optarg);
+ bitrate_nominal = atoi(optarg);
break;
case 'c':
break;
case 's':
- spt_target = strtoul(optarg, NULL, 10);
+ spt_nominal = strtoul(optarg, NULL, 10);
break;
default:
exit(EXIT_SUCCESS);
}
- if (spt_target && (spt_target >= 1000 || spt_target < 100))
+ if (spt_nominal && (spt_nominal >= 1000 || spt_nominal < 100))
print_usage(argv[0]);
for (i = 0; i < ARRAY_SIZE(can_calc_consts); i++) {
found = true;
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, spt_target, ref_clk, quiet);
- } else {
- for (j = 0; j < ARRAY_SIZE(common_bitrates); j++)
- print_bit_timing(btc, common_bitrates[j],
- spt_target, ref_clk, j);
+ for (j = 0; j < ARRAY_SIZE(btc->ref_clk); j++) {
+ if (opt_ref_clk)
+ ref_clk = opt_ref_clk;
+ else
+ ref_clk = btc->ref_clk[j];
+
+ if (!ref_clk)
+ break;
+
+ if (bitrate) {
+ print_bit_timing(btc, bitrate, spt_nominal, ref_clk, quiet);
+ } else {
+ for (k = 0; k < ARRAY_SIZE(common_bitrates); k++)
+ print_bit_timing(btc, common_bitrates[k],
+ spt_nominal, ref_clk, k);
+ }
+ printf("\n");
+
+ if (opt_ref_clk)
+ break;
}
- printf("\n");
}
if (!found) {
projects / can-utils.git / blobdiff