This is a sloppy logic analyzer using GPIOs. It comes with a script to isolate a CPU for polling. While this is definately not a production level analyzer, it can be a helpful first view when remote debugging. Read the documentation for details. Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> --- .../dev-tools/gpio-sloppy-logic-analyzer.rst | 72 ++++ Documentation/dev-tools/index.rst | 1 + drivers/gpio/Kconfig | 17 + drivers/gpio/Makefile | 1 + drivers/gpio/gpio-sloppy-logic-analyzer.c | 317 ++++++++++++++++++ tools/gpio/gpio-sloppy-logic-analyzer | 200 +++++++++++ 6 files changed, 608 insertions(+) create mode 100644 Documentation/dev-tools/gpio-sloppy-logic-analyzer.rst create mode 100644 drivers/gpio/gpio-sloppy-logic-analyzer.c create mode 100755 tools/gpio/gpio-sloppy-logic-analyzer diff --git a/Documentation/dev-tools/gpio-sloppy-logic-analyzer.rst b/Documentation/dev-tools/gpio-sloppy-logic-analyzer.rst new file mode 100644 index 000000000000..da807b341091 --- /dev/null +++ b/Documentation/dev-tools/gpio-sloppy-logic-analyzer.rst @@ -0,0 +1,72 @@ +============================================= +Linux Kernel GPIO based sloppy logic analyzer +============================================= + +:Author: Wolfram Sang + +Introduction +============ + +This document briefly describes how to run the GPIO based in-kernel sloppy +logic analyzer running on an isolated CPU. + +Note that this is a last resort analyzer which can be affected by latencies, +non-determinant code paths and non-maskable interrupts. It is called 'sloppy' +for a reason. However, for e.g. remote development, it may be useful to get a +first view and aid further debugging. + +Setup +===== + +Tell the kernel which GPIOs are used as probes. For a DT based system, you need +to use the following bindings. Because these bindings are only for debugging, +there is no official yaml file:: + + i2c-analyzer { + compatible = "gpio-sloppy-logic-analyzer"; + probe-gpios = <&gpio6 21 GPIO_OPEN_DRAIN>, <&gpio6 4 GPIO_OPEN_DRAIN>; + probe-names = "SCL", "SDA"; + }; + +Note that you must provide a name for every GPIO specified. Currently a +maximum of 8 probes are supported. 32 are likely possible but are not +implemented yet. + +Usage +===== + +The logic analyzer is configurable via files in debugfs. However, it is +strongly recommended to not use them directly, but to use the script +``tools/gpio/gpio-sloppy-logic-analyzer``. Besides checking parameters more +extensively, it will isolate the CPU core so you will have least disturbance +while measuring. + +The script has a help option explaining the parameters. For the above DT +snippet which analyzes an I2C bus at 400KHz on a Renesas Salvator-XS board, the +following settings are used: The isolated CPU shall be CPU1 because it is a big +core in a big.LITTLE setup. Because CPU1 is the default, we don't need a +parameter. The bus speed is 400kHz. So, the sampling theorem says we need to +sample at least at 800kHz. However, falling edges of both signals in an I2C +start condition happen faster, so we need a higher sampling frequency, e.g. +``-s 1500000`` for 1.5MHz. Also, we don't want to sample right away but wait +for a start condition on an idle bus. So, we need to set a trigger to a falling +edge on SDA while SCL stays high, i.e. ``-t 1H+2F``. Last is the duration, let +us assume 15ms here which results in the parameter ``-d 15000``. So, +altogether:: + + gpio-sloppy-logic-analyzer -s 1500000 -t 1H+2F -d 15000 + +Note that the process will return you back to the prompt but a sub-process is +still sampling in the background. Unless this has finished, you will not find a +result file in the current or specified directory. Please also note that +currently this sub-process is not killable! For the above example, we will then +need to trigger I2C communication:: + + i2cdetect -y -r <your bus number> + +Result is a .sr file to be consumed with PulseView or sigrok-cli from the free +`sigrok`_ project. It is a zip file which also contains the binary sample data +which may be consumed by other software. The filename is the logic analyzer +instance name plus a since-epoch timestamp. + +.. _sigrok: https://sigrok.org/ diff --git a/Documentation/dev-tools/index.rst b/Documentation/dev-tools/index.rst index 010a2af1e7d9..cdf1356a9c94 100644 --- a/Documentation/dev-tools/index.rst +++ b/Documentation/dev-tools/index.rst @@ -32,6 +32,7 @@ Documentation/dev-tools/testing-overview.rst kgdb kselftest kunit/index + gpio-sloppy-logic-analyzer .. only:: subproject and html diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 1dd0ec6727fd..e8fc8d973055 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1657,4 +1657,21 @@ config GPIO_MOCKUP endmenu +menu "GPIO hardware hacking tools" + +config GPIO_LOGIC_ANALYZER + tristate "Sloppy GPIO logic analyzer" + depends on (GPIOLIB || COMPILE_TEST) && EXPERT + help + This option enables support for a sloppy logic analyzer using polled + GPIOs. Use the 'tools/gpio/gpio-sloppy-logic-analyzer' script with + this driver. The script will make using it easier and will also + isolate a CPU for the polling task. Note that this is a last resort + analyzer which can be affected by latencies, non-determinant code + paths, or NMIs. However, for e.g. remote development, it may be useful + to get a first view and aid further debugging. + + If this driver is built as a module it will be called + 'gpio-sloppy-logic-analyzer'. +endmenu endif diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index d7c81e1611a4..5d3143c899b4 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -73,6 +73,7 @@ obj-$(CONFIG_GPIO_IT87) += gpio-it87.o obj-$(CONFIG_GPIO_IXP4XX) += gpio-ixp4xx.o obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o +obj-$(CONFIG_GPIO_LOGIC_ANALYZER) += gpio-sloppy-logic-analyzer.o obj-$(CONFIG_GPIO_LOGICVC) += gpio-logicvc.o obj-$(CONFIG_GPIO_LOONGSON1) += gpio-loongson1.o obj-$(CONFIG_GPIO_LOONGSON) += gpio-loongson.o diff --git a/drivers/gpio/gpio-sloppy-logic-analyzer.c b/drivers/gpio/gpio-sloppy-logic-analyzer.c new file mode 100644 index 000000000000..dc2c4c499e66 --- /dev/null +++ b/drivers/gpio/gpio-sloppy-logic-analyzer.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Sloppy logic analyzer using GPIOs (to be run on an isolated CPU) + * + * Use the 'gpio-sloppy-logic-analyzer' script in the 'tools/gpio' folder for + * easier usage and further documentation. Note that this is a last resort + * analyzer which can be affected by latencies and non-determinant code paths. + * However, for e.g. remote development, it may be useful to get a first view + * and aid further debugging. + * + * Copyright (C) Wolfram Sang <wsa@xxxxxxxxxxxxxxxxxxxx> + * Copyright (C) Renesas Electronics Corporation + */ + +#include <linux/ctype.h> +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/init.h> +#include <linux/ktime.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/slab.h> +#include <linux/sizes.h> +#include <linux/timekeeping.h> +#include <linux/vmalloc.h> + +#define GPIO_LA_NAME "gpio-sloppy-logic-analyzer" +#define GPIO_LA_DEFAULT_BUF_SIZE SZ_256K +/* can be increased but then we need to extend the u8 buffers */ +#define GPIO_LA_MAX_PROBES 8 +#define GPIO_LA_NUM_TESTS 1024 + +#define gpio_la_get_array(d, sptr) gpiod_get_array_value((d)->ndescs, (d)->desc, \ + (d)->info, sptr); + +struct gpio_la_poll_priv { + struct mutex lock; + u32 buf_idx; + unsigned long ndelay; + struct gpio_descs *descs; + struct debugfs_blob_wrapper blob; + struct dentry *debug_dir, *blob_dent; + struct debugfs_blob_wrapper meta; + unsigned long gpio_acq_delay; + struct device *dev; + unsigned int trig_len; + u8 *trig_data; +}; + +static struct dentry *gpio_la_poll_debug_dir; + +static int fops_capture_set(void *data, u64 val) +{ + struct gpio_la_poll_priv *priv = data; + u8 *la_buf = priv->blob.data; + unsigned long state = 0; + int i, ret; + + if (!val) + return 0; + + if (!la_buf) + return -ENOMEM; + + mutex_lock(&priv->lock); + if (priv->blob_dent) { + debugfs_remove(priv->blob_dent); + priv->blob_dent = NULL; + } + + priv->buf_idx = 0; + + local_irq_disable(); + preempt_disable_notrace(); + + for (i = 0; i < priv->trig_len; i+= 2) { + do { + ret = gpio_la_get_array(priv->descs, &state); + if (ret) + goto gpio_err; + + ndelay(priv->ndelay); + } while ((state & priv->trig_data[i]) != priv->trig_data[i + 1]); + } + + /* With triggers, final state is also the first sample */ + if (priv->trig_len) + la_buf[priv->buf_idx++] = state; + + while (priv->buf_idx < priv->blob.size) { + ret = gpio_la_get_array(priv->descs, &state); + if (ret) + goto gpio_err; + + la_buf[priv->buf_idx++] = state; + ndelay(priv->ndelay); + } +gpio_err: + preempt_enable_notrace(); + local_irq_enable(); + if (ret) + dev_err(priv->dev, "couldn't read GPIOs: %d\n", ret); + + kfree(priv->trig_data); + priv->trig_data = NULL; + priv->trig_len = 0; + + priv->blob_dent = debugfs_create_blob("sample_data", 0400, priv->debug_dir, &priv->blob); + mutex_unlock(&priv->lock); + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_capture, NULL, fops_capture_set, "%llu\n"); + +static int fops_buf_size_get(void *data, u64 *val) +{ + struct gpio_la_poll_priv *priv = data; + + *val = priv->blob.size; + + return 0; +} + +static int fops_buf_size_set(void *data, u64 val) +{ + struct gpio_la_poll_priv *priv = data; + int ret = 0; + void *p; + + if (!val) + return -EINVAL; + + mutex_lock(&priv->lock); + + vfree(priv->blob.data); + p = vzalloc(val); + if (!p) { + val = 0; + ret = -ENOMEM; + } + + priv->blob.data = p; + priv->blob.size = val; + + mutex_unlock(&priv->lock); + return ret; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_buf_size, fops_buf_size_get, fops_buf_size_set, "%llu\n"); + +static int trigger_open(struct inode *inode, struct file *file) +{ + return single_open(file, NULL, inode->i_private); +} + +static ssize_t trigger_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *offset) +{ + struct seq_file *m = file->private_data; + struct gpio_la_poll_priv *priv = m->private; + char *buf; + + /* upper limit is arbitrary */ + if (count == 0 || count > 2048 || count & 1) + return -EINVAL; + + buf = memdup_user(ubuf, count); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + priv->trig_data = buf; + priv->trig_len = count; + + return count; +} + +static const struct file_operations fops_trigger = { + .owner = THIS_MODULE, + .open = trigger_open, + .write = trigger_write, + .llseek = no_llseek, + .release = single_release, +}; + +static int gpio_la_poll_probe(struct platform_device *pdev) +{ + struct gpio_la_poll_priv *priv; + struct device *dev = &pdev->dev; + unsigned long state; + ktime_t start_time, end_time; + const char *gpio_names[GPIO_LA_MAX_PROBES]; + char *meta = NULL; + unsigned int meta_len = 0; + int ret, i; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mutex_init(&priv->lock); + + fops_buf_size_set(priv, GPIO_LA_DEFAULT_BUF_SIZE); + + priv->descs = devm_gpiod_get_array(dev, "probe", GPIOD_IN); + if (IS_ERR(priv->descs)) + return PTR_ERR(priv->descs); + + /* artificial limit to keep 1 byte per sample for now */ + if (priv->descs->ndescs > GPIO_LA_MAX_PROBES) + return -ERANGE; + + ret = device_property_read_string_array(dev, "probe-names", gpio_names, + priv->descs->ndescs); + if (ret >= 0 && ret != priv->descs->ndescs) + ret = -ENOSTR; + if (ret < 0) { + dev_err(dev, "error naming the GPIOs: %d\n", ret); + return ret; + } + + for (i = 0; i < priv->descs->ndescs; i++) { + unsigned int add_len; + + if (gpiod_cansleep(priv->descs->desc[i])) + return -EREMOTE; + + gpiod_set_consumer_name(priv->descs->desc[i], gpio_names[i]); + + /* '10' is length of 'probe00=\n\0' */ + add_len = strlen(gpio_names[i]) + 10; + meta = devm_krealloc(dev, meta, meta_len + add_len, GFP_KERNEL); + if (!meta) + return -ENOMEM; + snprintf(meta + meta_len, add_len, "probe%02d=%s\n", i + 1, gpio_names[i]); + /* ' - 1' to skip the NUL terminator */ + meta_len += add_len - 1; + } + + platform_set_drvdata(pdev, priv); + priv->dev = dev; + + /* Measure delay of reading GPIOs */ + local_irq_disable(); + preempt_disable_notrace(); + start_time = ktime_get(); + for (i = 0, ret = 0; i < GPIO_LA_NUM_TESTS && ret == 0; i++) + ret = gpio_la_get_array(priv->descs, &state); + end_time = ktime_get(); + preempt_enable_notrace(); + local_irq_enable(); + if (ret) { + dev_err(dev, "couldn't read GPIOs: %d\n", ret); + return ret; + } + + priv->gpio_acq_delay = ktime_sub(end_time, start_time) / GPIO_LA_NUM_TESTS; + + priv->meta.data = meta; + priv->meta.size = meta_len; + priv->debug_dir = debugfs_create_dir(dev_name(dev), gpio_la_poll_debug_dir); + debugfs_create_blob("meta_data", 0400, priv->debug_dir, &priv->meta); + debugfs_create_ulong("delay_ns_acquisition", 0400, priv->debug_dir, &priv->gpio_acq_delay); + debugfs_create_ulong("delay_ns_user", 0600, priv->debug_dir, &priv->ndelay); + debugfs_create_file_unsafe("buf_size", 0600, priv->debug_dir, priv, &fops_buf_size); + debugfs_create_file_unsafe("capture", 0200, priv->debug_dir, priv, &fops_capture); + debugfs_create_file_unsafe("trigger", 0200, priv->debug_dir, priv, &fops_trigger); + + return 0; +} + +static int gpio_la_poll_remove(struct platform_device *pdev) +{ + struct gpio_la_poll_priv *priv = platform_get_drvdata(pdev); + + mutex_lock(&priv->lock); + debugfs_remove_recursive(priv->debug_dir); + mutex_unlock(&priv->lock); + + return 0; +} + +static const struct of_device_id gpio_la_poll_of_match[] = { + { .compatible = GPIO_LA_NAME, }, + { } +}; +MODULE_DEVICE_TABLE(of, gpio_la_poll_of_match); + +static struct platform_driver gpio_la_poll_device_driver = { + .probe = gpio_la_poll_probe, + .remove = gpio_la_poll_remove, + .driver = { + .name = GPIO_LA_NAME, + .of_match_table = gpio_la_poll_of_match, + } +}; + +static int __init gpio_la_poll_init(void) +{ + gpio_la_poll_debug_dir = debugfs_create_dir(GPIO_LA_NAME, NULL); + + return platform_driver_register(&gpio_la_poll_device_driver); +} +late_initcall(gpio_la_poll_init); + +static void __exit gpio_la_poll_exit(void) +{ + platform_driver_unregister(&gpio_la_poll_device_driver); + debugfs_remove_recursive(gpio_la_poll_debug_dir); +} +module_exit(gpio_la_poll_exit); + +MODULE_AUTHOR("Wolfram Sang <wsa@xxxxxxxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Sloppy logic analyzer using GPIOs"); +MODULE_LICENSE("GPL v2"); diff --git a/tools/gpio/gpio-sloppy-logic-analyzer b/tools/gpio/gpio-sloppy-logic-analyzer new file mode 100755 index 000000000000..345cdd67bfd1 --- /dev/null +++ b/tools/gpio/gpio-sloppy-logic-analyzer @@ -0,0 +1,200 @@ +#! /bin/sh +# Helper script for the Linux Kernel GPIO sloppy logic analyzer +# +# Copyright (C) Wolfram Sang <wsa@xxxxxxxxxxxxxxxxxxxx> +# Copyright (C) Renesas Electronics Corporation +# +# TODO: support SI units in command line parameters? + +INITCPU= +SAMPLEFREQ=1000000 +NUMSAMPLES=250000 +LASYSFSDIR= +CPUSETDIR='/dev/cpuset' +LACPUSETDIR="$CPUSETDIR/gpio-sloppy-logic-analyzer" +SYSFSDIR='/sys/kernel/debug/gpio-sloppy-logic-analyzer/' +OUTPUTDIR="$PWD" +TRIGGERDAT= +TRIGGER_BINDAT= +NEEDEDCMDS='taskset zip' +MAX_CHANS=8 + +print_help() +{ + cat <<EOF +$0 - helper script for the Linux Kernel Sloppy GPIO Logic Analyzer +Available options: + -d|--duration-us <n>: number of microseconds to sample. Overrides -n, no default value. + -h|--help: print this help + -i|--init <n>: which CPU to isolate for sampling. Only needed once. Default <1>. + Remember that a more powerful CPU gives you higher sample speeds. + Also CPU0 is not recommended as it usually does extra bookkeeping. + -n|--num_samples <n>: number of samples to acquire. Default <$NUMSAMPLES> + -o|--output-dir <str>: directory to put the result files. Default: current dir + -p|--path <str>: path to Logic Analyzer dir in case you have multiple instances. + Default to first instance found. + -s|--sample_freq <n>: desired sample frequency. Might be capped if too large. Default: 1MHz. + -t|--trigger <str>: pattern to use as trigger. <str> consists of two-char pairs. First + char is channel number starting at "1". Second char is trigger level: + "L" - low; "H" - high; "R" - rising; "F" - falling + These pairs can be combined with "+", so "1H+2F" triggers when probe 1 + is high while probe 2 has a falling edge. You can have multiple triggers + combined with ",". So, "1H+2F,1H+2R" is like the example before but it + waits for a rising edge on probe 2 while probe 1 is still high after the + first trigger has been met. + Trigger data will only be used for the next capture and then be erased. +Examples: +Samples $NUMSAMPLES at 1MHz with an already prepared CPU or automatically prepares CPU1 if needed + '$0' +Samples 50us at 2MHz waiting for falling edge on channel 2. CPU usage as above. + '$0 -d 50 -s 2000000 -t "2F"' + +Note that the process exits after checking all parameters but a sub-process still works in +the background. The result is only available once the sub-process finishes. As the time of +writing, the sub-process is not killable, so be extra careful that your triggers work. + +Result is a .sr file to be consumed with PulseView from the free Sigrok project. It is +a zip file which also contains the binary sample data which may be consumed by others. +The filename is the logic analyzer instance name plus a since-epoch timestamp. +EOF +} + +set_newmask() +{ + local f + for f in $(find $1 -iname "$2"); do echo $NEWMASK > $f 2>/dev/null; done +} + +init_cpu() +{ + local CPU OLDMASK + + CPU="$1" + [ ! -d $CPUSETDIR ] && mkdir $CPUSETDIR + mount | grep -q $CPUSETDIR || mount -t cpuset cpuset $CPUSETDIR + [ ! -d $LACPUSETDIR ] && mkdir $LACPUSETDIR + + echo $CPU > $LACPUSETDIR/cpus + echo 1 > $LACPUSETDIR/cpu_exclusive + echo 0 > $LACPUSETDIR/mems + + OLDMASK=$(cat /proc/irq/default_smp_affinity) + val=$((0x$OLDMASK & ~(1 << $CPU))) + NEWMASK=$(printf "%x" $val) + + set_newmask '/proc/irq' '*smp_affinity' + set_newmask '/sys/devices/virtual/workqueue/' 'cpumask' + + # Move tasks away from isolated CPU + for p in $(ps -o pid | tail -n +2); do + MASK=$(taskset -p $p) + [ "${MASK##*: }" != "$OLDMASK" ] && continue + taskset -p $NEWMASK $p + done 2>/dev/null >/dev/null + + echo 1 > /sys/module/rcupdate/parameters/rcu_cpu_stall_suppress +} + +parse_triggerdat() +{ + local OLDIFS mask val1 val2 chan mode bit t c + + OLDIFS="$IFS" + IFS=','; for t in $1; do + mask=0; val1=0; val2=0 + IFS='+'; for c in $t; do + chan=${c%[lhfrLHFR]} + mode=${c#$chan} + # Check if we could parse something and the channel number fits + [ $chan != $c -a $chan -le $MAX_CHANS ] 2> /dev/null || { echo "Syntax error: $c" && exit 1; } + bit=$((1 << ($chan - 1))) + mask=$(($mask | $bit)) + case $mode in + [hH]) val1=$(($val1 | $bit)); val2=$(($val2 | $bit));; + [fF]) val1=$(($val1 | $bit));; + [rR]) val2=$(($val2 | $bit));; + esac + done + TRIGGER_BINDAT="$TRIGGER_BINDAT$(printf '\\%o\\%o' $mask $val1)" + [ $val1 -ne $val2 ] && TRIGGER_BINDAT="$TRIGGER_BINDAT$(printf '\\%o\\%o' $mask $val2)" + done + IFS="$OLDIFS" +} + +do_capture() +{ + local SRTMP ZIPNAME + + taskset $1 echo 1 > $LASYSFSDIR/capture + + SRTMP=$(mktemp -d) + echo 1 > $SRTMP/version + cp $LASYSFSDIR/sample_data $SRTMP/logic-1-1 + cat > $SRTMP/metadata <<EOF +[global] +sigrok version=0.2.0 + +[device 1] +capturefile=logic-1 +total probes=$(cat $LASYSFSDIR/meta_data | wc -l) +samplerate=${SAMPLEFREQ}Hz +unitsize=1 +EOF + cat $LASYSFSDIR/meta_data >> $SRTMP/metadata + + ZIPNAME="$OUTPUTDIR/${LASYSFSDIR##*/}-$(date +%s).sr" + zip -jq $ZIPNAME $SRTMP/* + rm -rf $SRTMP +} + +REP=$(getopt -a -l path:,init:,sample_freq:,num_samples:,duration-us:,trigger:,output-dir:,help -o i:s:n:d:t:o:h -- "$@") || exit 1 +eval set -- "$REP" +while true; do + case "$1" in + -d|--duration-us) DURATION="$2"; shift 2;; + -h|--help) print_help; exit 0;; + -i|--init) INITCPU="$2"; shift 2;; + -n|--num_samples) NUMSAMPLES="$2"; shift 2;; + -o|--output-dir) OUTPUTDIR="$2"; shift 2;; + -p|--path) LASYSFSDIR="$2"; shift 2;; + -s|--sample_freq) SAMPLEFREQ="$2"; shift 2;; + -t|--trigger) TRIGGERDAT="$2"; shift 2;; + --) shift; break;; + *) echo "error parsing commandline: $@"; exit 1;; + esac +done + +for f in $NEEDEDCMDS; do + command -v $f >/dev/null || { echo "Command '$f' not found"; exit 1; } +done + +[ $SAMPLEFREQ -eq 0 ] && echo "Invalid sample frequency" && exit 1 + +[ -z "$LASYSFSDIR" ] && LASYSFSDIR="$SYSFSDIR/$(ls -1 $SYSFSDIR | head -n1)" +[ ! -d "$LASYSFSDIR" ] && echo "LA directory '$LASYSFSDIR' not found!" && exit 1 + +[ -n "$INITCPU" ] && init_cpu $INITCPU +[ ! -d "$LACPUSETDIR" ] && echo "Auto-Isolating CPU1" && init_cpu 1 + +NDELAY=$((1000000000 / $SAMPLEFREQ)) +NDELAY_ACQ=$(cat $LASYSFSDIR/delay_ns_acquisition) +[ $NDELAY_ACQ -eq 0 ] && echo "Invalid acquisition delay received" && exit 1 +NDELAY_USER=$(($NDELAY - $NDELAY_ACQ)) +MAXFREQ=$((1000000000 / $NDELAY_ACQ)) + +[ $NDELAY_USER -lt 0 ] && NDELAY_USER=0 && SAMPLEFREQ=$MAXFREQ && echo "Capping sample_freq to $MAXFREQ" +echo $NDELAY_USER > $LASYSFSDIR/delay_ns_user + +[ -n "$DURATION" ] && NUMSAMPLES=$(($SAMPLEFREQ * $DURATION / 1000000)) +echo $NUMSAMPLES > $LASYSFSDIR/buf_size + +if [ -n "$TRIGGERDAT" ]; then + parse_triggerdat $TRIGGERDAT + printf "$TRIGGER_BINDAT" > $LASYSFSDIR/trigger 2>/dev/null + [ $? -gt 0 ] && echo "Trigger data '$TRIGGERDAT' rejected" && exit 1 +fi + +CPU=$(cat $LACPUSETDIR/effective_cpus) +[ -z "$CPU" ] && echo "No isolated CPU found" && exit 1 +CPUMASK=$((1 << $CPU)) +do_capture $CPUMASK & -- 2.30.2