1 #!/bin/sh -eu
2 # SPDX-License-Identifier: GPL-2.0
3 #
4 # Helper script for the Linux Kernel GPIO slop
5 #
6 # Copyright (C) Wolfram Sang <wsa@sang-engineer
7 # Copyright (C) Renesas Electronics Corporatio
8
9 samplefreq=1000000
10 numsamples=250000
11 cpusetdefaultdir='/sys/fs/cgroup'
12 cpusetprefix='cpuset.'
13 debugdir='/sys/kernel/debug'
14 ladirname='gpio-sloppy-logic-analyzer'
15 outputdir="$PWD"
16 neededcmds='taskset zip'
17 max_chans=8
18 duration=
19 initcpu=
20 listinstances=0
21 lainstance=
22 lasysfsdir=
23 triggerdat=
24 trigger_bindat=
25 progname="${0##*/}"
26 print_help()
27 {
28 cat << EOF
29 $progname - helper script for the Linux Kernel
30 Available options:
31 -c|--cpu <n>: which CPU to isolate for
32 Remember that a more pow
33 Also CPU0 is not recomme
34 -d|--duration-us <SI-n>: number of mic
35 -h|--help: print this help
36 -i|--instance <str>: name of the logic
37 to first instance
38 -k|--kernel-debug-dir <str>: path to t
39 -l|--list-instances: list all availabl
40 -n|--num_samples <SI-n>: number of sam
41 -o|--output-dir <str>: directory to pu
42 -s|--sample_freq <SI-n>: desired sampl
43 Default: <100
44 -t|--trigger <str>: pattern to use as
45 char is channel nu
46 "L" - low; "H" - h
47 These pairs can be
48 is high while prob
49 combined with ",".
50 waits for a rising
51 first trigger has
52 Trigger data will
53
54 <SI-n> is an integer value where SI units "T",
55
56 Examples:
57 Samples $numsamples values at 1MHz with an alr
58 use the first logic analyzer instance found:
59 '$progname'
60 Samples 50us at 2MHz waiting for a falling edg
61 '$progname -d 50 -s 2M -t "2F"'
62
63 Note that the process exits after checking all
64 the background. The result is only available o
65
66 Result is a .sr file to be consumed with Pulse
67 a zip file which also contains the binary samp
68 The filename is the logic analyzer instance na
69 EOF
70 }
71
72 fail()
73 {
74 echo "$1"
75 exit 1
76 }
77
78 parse_si()
79 {
80 conv_si="$(printf $1 | sed 's/[tT]+\?/
81 si_val="$((conv_si))"
82 }
83 set_newmask()
84 {
85 for f in $(find "$1" -iname "$2"); do
86 }
87
88 init_cpu()
89 {
90 isol_cpu="$1"
91
92 [ -d "$lacpusetdir" ] || mkdir "$lacpu
93
94 cur_cpu=$(cat "${lacpusetfile}cpus")
95 [ "$cur_cpu" = "$isol_cpu" ] && return
96 [ -z "$cur_cpu" ] || fail "CPU$isol_cp
97
98 echo "$isol_cpu" > "${lacpusetfile}cpu
99 echo 1 > "${lacpusetfile}cpu_exclusive
100 echo 0 > "${lacpusetfile}mems"
101
102 oldmask=$(cat /proc/irq/default_smp_af
103 newmask=$(printf "%x" $((0x$oldmask &
104
105 set_newmask '/proc/irq' '*smp_affinity
106 set_newmask '/sys/devices/virtual/work
107
108 # Move tasks away from isolated CPU
109 for p in $(ps -o pid | tail -n +2); do
110 mask=$(taskset -p "$p") || con
111 # Ignore tasks with a custom m
112 [ "${mask##*: }" = "$oldmask"
113 taskset -p "$newmask" "$p" ||
114 done 2>/dev/null >/dev/null
115
116 # Big hammer! Working with 'rcu_moment
117 # still printed warnings. Same for re-
118 echo 1 > /sys/module/rcupdate/paramete
119
120 cpufreqgov="/sys/devices/system/cpu/cp
121 [ -w "$cpufreqgov" ] && echo 'performa
122 }
123
124 parse_triggerdat()
125 {
126 oldifs="$IFS"
127 IFS=','; for trig in $1; do
128 mask=0; val1=0; val2=0
129 IFS='+'; for elem in $trig; do
130 chan=${elem%[lhfrLHFR]
131 mode=${elem#$chan}
132 # Check if we could pa
133 [ "$chan" != "$elem" ]
134 bit=$((1 << (chan - 1)
135 mask=$((mask | bit))
136 case $mode in
137 [hH]) val1=$((
138 [fF]) val1=$((
139 [rR]) val2=$((
140 esac
141 done
142 trigger_bindat="$trigger_binda
143 [ $val1 -ne $val2 ] && trigger
144 done
145 IFS="$oldifs"
146 }
147
148 do_capture()
149 {
150 taskset "$1" echo 1 > "$lasysfsdir"/ca
151
152 srtmp=$(mktemp -d)
153 echo 1 > "$srtmp"/version
154 cp "$lasysfsdir"/sample_data "$srtmp"/
155 cat > "$srtmp"/metadata << EOF
156 [global]
157 sigrok version=0.2.0
158
159 [device 1]
160 capturefile=logic-1
161 total probes=$(wc -l < "$lasysfsdir"/meta_data
162 samplerate=${samplefreq}Hz
163 unitsize=1
164 EOF
165 cat "$lasysfsdir"/meta_data >> "$srtmp
166
167 zipname="$outputdir/${lasysfsdir##*/}-
168 zip -jq "$zipname" "$srtmp"/*
169 rm -rf "$srtmp"
170 delay_ack=$(cat "$lasysfsdir"/delay_ns
171 [ "$delay_ack" -eq 0 ] && delay_ack=1
172 echo "Logic analyzer done. Saved '$zip
173 echo "Max sample frequency this time:
174 }
175
176 rep=$(getopt -a -l cpu:,duration-us:,help,inst
177 eval set -- "$rep"
178 while true; do
179 case "$1" in
180 -c|--cpu) initcpu="$2"; shift;;
181 -d|--duration-us) parse_si $2; duratio
182 -h|--help) print_help; exit 0;;
183 -i|--instance) lainstance="$2"; shift;
184 -k|--kernel-debug-dir) debugdir="$2";
185 -l|--list-instances) listinstances=1;;
186 -n|--num_samples) parse_si $2; numsamp
187 -o|--output-dir) outputdir="$2"; shift
188 -s|--sample_freq) parse_si $2; samplef
189 -t|--trigger) triggerdat="$2"; shift;;
190 --) break;;
191 *) fail "error parsing command line: $
192 esac
193 shift
194 done
195
196 for f in $neededcmds; do
197 command -v "$f" >/dev/null || fail "Co
198 done
199
200 # print cpuset mountpoint if any, errorcode >
201 cpusetdir=$(awk '$3 == "cgroup" && $4 ~ /cpuse
202 if [ -z "$cpusetdir" ]; then
203 cpusetdir="$cpusetdefaultdir"
204 [ -d $cpusetdir ] || mkdir $cpusetdir
205 mount -t cgroup -o cpuset none $cpuset
206 fi
207
208 lacpusetdir="$cpusetdir/$ladirname"
209 lacpusetfile="$lacpusetdir/$cpusetprefix"
210 sysfsdir="$debugdir/$ladirname"
211
212 [ "$samplefreq" -ne 0 ] || fail "Invalid sampl
213
214 [ -d "$sysfsdir" ] || fail "Could not find log
215 [ -x "$sysfsdir" ] || fail "Could not access l
216
217 [ $listinstances -gt 0 ] && find "$sysfsdir" -
218
219 if [ -n "$lainstance" ]; then
220 lasysfsdir="$sysfsdir/$lainstance"
221 else
222 lasysfsdir=$(find "$sysfsdir" -mindept
223 fi
224 [ -d "$lasysfsdir" ] || fail "Logic analyzer d
225 [ -d "$outputdir" ] || fail "Output directory
226
227 [ -n "$initcpu" ] && init_cpu "$initcpu"
228 [ -d "$lacpusetdir" ] || { echo "Auto-Isolatin
229
230 ndelay=$((1000000000 / samplefreq))
231 echo "$ndelay" > "$lasysfsdir"/delay_ns
232
233 [ -n "$duration" ] && numsamples=$((samplefreq
234 echo $numsamples > "$lasysfsdir"/buf_size
235
236 if [ -n "$triggerdat" ]; then
237 parse_triggerdat "$triggerdat"
238 printf "$trigger_bindat" > "$lasysfsdi
239 fi
240
241 workcpu=$(cat "${lacpusetfile}effective_cpus")
242 [ -n "$workcpu" ] || fail "No isolated CPU fou
243 cpumask=$(printf '%x' $((1 << workcpu)))
244 instance=${lasysfsdir##*/}
245 echo "Setting up '$instance': $numsamples samp
246 do_capture "$cpumask" &
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