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[media] dvb: Add DVBv5 statistics properties
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The DVBv3 statistics parameters are limited on several ways:
        - It doesn't provide any way to indicate the used measure,
	  so userspace need to guess how to calculate/use it;
        - Only a limited set of stats are supported;
        - Can't be called in a way to require them to be filled
          all at once (atomic reads from the hardware), with may
          cause troubles on interpreting them on userspace;
        - On some OFDM delivery systems, the carriers can be
          independently modulated, having different properties.
          Currently, there's no way to report per-layer stats.
To address the above issues, adding a new DVBv5-based stats API.
While here, correct inner code nomenclature on a few places.

Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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Mauro Carvalho Chehab committed Jan 23, 2013
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2 changes: 1 addition & 1 deletion Documentation/DocBook/media/dvb/dvbapi.xml
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Expand Up @@ -84,7 +84,7 @@ Added ISDB-T test originally written by Patrick Boettcher


<title>LINUX DVB API</title>
<subtitle>Version 5.8</subtitle>
<subtitle>Version 5.10</subtitle>
<!-- ADD THE CHAPTERS HERE -->
<chapter id="dvb_introdution">
&sub-intro;
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180 changes: 179 additions & 1 deletion Documentation/DocBook/media/dvb/dvbproperty.xml
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Expand Up @@ -7,14 +7,41 @@ the capability ioctls weren't implemented yet via the new way.</para>
<para>The typical usage for the <constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant>
API is to replace the ioctl's were the <link linkend="dvb-frontend-parameters">
struct <constant>dvb_frontend_parameters</constant></link> were used.</para>
<section id="dtv-stats">
<title>DTV stats type</title>
<programlisting>
struct dtv_stats {
__u8 scale; /* enum fecap_scale_params type */
union {
__u64 uvalue; /* for counters and relative scales */
__s64 svalue; /* for 1/1000 dB measures */
};
} __packed;
</programlisting>
</section>
<section id="dtv-fe-stats">
<title>DTV stats type</title>
<programlisting>
#define MAX_DTV_STATS 4

struct dtv_fe_stats {
__u8 len;
struct dtv_stats stat[MAX_DTV_STATS];
} __packed;
</programlisting>
</section>

<section id="dtv-property">
<title>DTV property type</title>
<programlisting>
/* Reserved fields should be set to 0 */

struct dtv_property {
__u32 cmd;
__u32 reserved[3];
union {
__u32 data;
struct dtv_fe_stats st;
struct {
__u8 data[32];
__u32 len;
Expand Down Expand Up @@ -440,7 +467,7 @@ typedef enum fe_delivery_system {
<title><constant>DTV-ISDBT-LAYER*</constant> parameters</title>
<para>ISDB-T channels can be coded hierarchically. As opposed to DVB-T in
ISDB-T hierarchical layers can be decoded simultaneously. For that
reason a ISDB-T demodulator has 3 viterbi and 3 reed-solomon-decoders.</para>
reason a ISDB-T demodulator has 3 Viterbi and 3 Reed-Solomon decoders.</para>
<para>ISDB-T has 3 hierarchical layers which each can use a part of the
available segments. The total number of segments over all layers has
to 13 in ISDB-T.</para>
Expand Down Expand Up @@ -850,6 +877,147 @@ enum fe_interleaving {
<para>use the special macro LNA_AUTO to set LNA auto</para>
</section>
</section>

<section id="frontend-stat-properties">
<title>Frontend statistics indicators</title>
<para>The values are returned via <constant>dtv_property.stat</constant>.
If the property is supported, <constant>dtv_property.stat.len</constant> is bigger than zero.</para>
<para>For most delivery systems, <constant>dtv_property.stat.len</constant>
will be 1 if the stats is supported, and the properties will
return a single value for each parameter.</para>
<para>It should be noticed, however, that new OFDM delivery systems
like ISDB can use different modulation types for each group of
carriers. On such standards, up to 3 groups of statistics can be
provided, and <constant>dtv_property.stat.len</constant> is updated
to reflect the "global" metrics, plus one metric per each carrier
group (called "layer" on ISDB).</para>
<para>So, in order to be consistent with other delivery systems, the first
value at <link linkend="dtv-stats"><constant>dtv_property.stat.dtv_stats</constant></link>
array refers to the global metric. The other elements of the array
represent each layer, starting from layer A(index 1),
layer B (index 2) and so on.</para>
<para>The number of filled elements are stored at <constant>dtv_property.stat.len</constant>.</para>
<para>Each element of the <constant>dtv_property.stat.dtv_stats</constant> array consists on two elements:</para>
<itemizedlist mark='opencircle'>
<listitem><para><constant>svalue</constant> or <constant>uvalue</constant>, where
<constant>svalue</constant> is for signed values of the measure (dB measures)
and <constant>uvalue</constant> is for unsigned values (counters, relative scale)</para></listitem>
<listitem><para><constant>scale</constant> - Scale for the value. It can be:</para>
<section id = "fecap-scale-params">
<itemizedlist mark='bullet'>
<listitem><para><constant>FE_SCALE_NOT_AVAILABLE</constant> - The parameter is supported by the frontend, but it was not possible to collect it (could be a transitory or permanent condition)</para></listitem>
<listitem><para><constant>FE_SCALE_DECIBEL</constant> - parameter is a signed value, measured in 1/1000 dB</para></listitem>
<listitem><para><constant>FE_SCALE_RELATIVE</constant> - parameter is a unsigned value, where 0 means 0% and 65535 means 100%.</para></listitem>
<listitem><para><constant>FE_SCALE_COUNTER</constant> - parameter is a unsigned value that counts the occurrence of an event, like bit error, block error, or lapsed time.</para></listitem>
</itemizedlist>
</section>
</listitem>
</itemizedlist>
<section id="DTV-STAT-SIGNAL-STRENGTH">
<title><constant>DTV_STAT_SIGNAL_STRENGTH</constant></title>
<para>Indicates the signal strength level at the analog part of the tuner or of the demod.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_DECIBEL</constant> - signal strength is in 0.0001 dBm units, power measured in miliwatts. This value is generally negative.</listitem>
<listitem><constant>FE_SCALE_RELATIVE</constant> - The frontend provides a 0% to 100% measurement for power (actually, 0 to 65535).</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-CNR">
<title><constant>DTV_STAT_CNR</constant></title>
<para>Indicates the Signal to Noise ratio for the main carrier.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_DECIBEL</constant> - Signal/Noise ratio is in 0.0001 dB units.</listitem>
<listitem><constant>FE_SCALE_RELATIVE</constant> - The frontend provides a 0% to 100% measurement for Signal/Noise (actually, 0 to 65535).</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-PRE-ERROR-BIT-COUNT">
<title><constant>DTV_STAT_PRE_ERROR_BIT_COUNT</constant></title>
<para>Measures the number of bit errors before the forward error correction (FEC) on the inner coding block (before Viterbi, LDPC or other inner code).</para>
<para>This measure is taken during the same interval as <constant>DTV_STAT_PRE_TOTAL_BIT_COUNT</constant>.</para>
<para>In order to get the BER (Bit Error Rate) measurement, it should be divided by
<link linkend="DTV-STAT-PRE-TOTAL-BIT-COUNT"><constant>DTV_STAT_PRE_TOTAL_BIT_COUNT</constant></link>.</para>
<para>This measurement is monotonically increased, as the frontend gets more bit count measurements.
The frontend may reset it when a channel/transponder is tuned.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of error bits counted before the inner coding.</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-PRE-TOTAL-BIT-COUNT">
<title><constant>DTV_STAT_PRE_TOTAL_BIT_COUNT</constant></title>
<para>Measures the amount of bits received before the inner code block, during the same period as
<link linkend="DTV-STAT-PRE-ERROR-BIT-COUNT"><constant>DTV_STAT_PRE_ERROR_BIT_COUNT</constant></link> measurement was taken.</para>
<para>It should be noticed that this measurement can be smaller than the total amount of bits on the transport stream,
as the frontend may need to manually restart the measurement, loosing some data between each measurement interval.</para>
<para>This measurement is monotonically increased, as the frontend gets more bit count measurements.
The frontend may reset it when a channel/transponder is tuned.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of bits counted while measuring
<link linkend="DTV-STAT-PRE-ERROR-BIT-COUNT"><constant>DTV_STAT_PRE_ERROR_BIT_COUNT</constant></link>.</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-POST-ERROR-BIT-COUNT">
<title><constant>DTV_STAT_POST_ERROR_BIT_COUNT</constant></title>
<para>Measures the number of bit errors after the forward error correction (FEC) done by inner code block (after Viterbi, LDPC or other inner code).</para>
<para>This measure is taken during the same interval as <constant>DTV_STAT_POST_TOTAL_BIT_COUNT</constant>.</para>
<para>In order to get the BER (Bit Error Rate) measurement, it should be divided by
<link linkend="DTV-STAT-POST-TOTAL-BIT-COUNT"><constant>DTV_STAT_POST_TOTAL_BIT_COUNT</constant></link>.</para>
<para>This measurement is monotonically increased, as the frontend gets more bit count measurements.
The frontend may reset it when a channel/transponder is tuned.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of error bits counted after the inner coding.</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-POST-TOTAL-BIT-COUNT">
<title><constant>DTV_STAT_POST_TOTAL_BIT_COUNT</constant></title>
<para>Measures the amount of bits received after the inner coding, during the same period as
<link linkend="DTV-STAT-POST-ERROR-BIT-COUNT"><constant>DTV_STAT_POST_ERROR_BIT_COUNT</constant></link> measurement was taken.</para>
<para>It should be noticed that this measurement can be smaller than the total amount of bits on the transport stream,
as the frontend may need to manually restart the measurement, loosing some data between each measurement interval.</para>
<para>This measurement is monotonically increased, as the frontend gets more bit count measurements.
The frontend may reset it when a channel/transponder is tuned.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of bits counted while measuring
<link linkend="DTV-STAT-POST-ERROR-BIT-COUNT"><constant>DTV_STAT_POST_ERROR_BIT_COUNT</constant></link>.</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-ERROR-BLOCK-COUNT">
<title><constant>DTV_STAT_ERROR_BLOCK_COUNT</constant></title>
<para>Measures the number of block errors after the outer forward error correction coding (after Reed-Solomon or other outer code).</para>
<para>This measurement is monotonically increased, as the frontend gets more bit count measurements.
The frontend may reset it when a channel/transponder is tuned.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of error blocks counted after the outer coding.</listitem>
</itemizedlist>
</section>
<section id="DTV-STAT-TOTAL-BLOCK-COUNT">
<title><constant>DTV-STAT_TOTAL_BLOCK_COUNT</constant></title>
<para>Measures the total number of blocks received during the same period as
<link linkend="DTV-STAT-ERROR-BLOCK-COUNT"><constant>DTV_STAT_ERROR_BLOCK_COUNT</constant></link> measurement was taken.</para>
<para>It can be used to calculate the PER indicator, by dividing
<link linkend="DTV-STAT-ERROR-BLOCK-COUNT"><constant>DTV_STAT_ERROR_BLOCK_COUNT</constant></link>
by <link linkend="DTV-STAT-TOTAL-BLOCK-COUNT"><constant>DTV-STAT-TOTAL-BLOCK-COUNT</constant></link>.</para>
<para>Possible scales for this metric are:</para>
<itemizedlist mark='bullet'>
<listitem><constant>FE_SCALE_NOT_AVAILABLE</constant> - it failed to measure it, or the measurement was not complete yet.</listitem>
<listitem><constant>FE_SCALE_COUNTER</constant> - Number of blocks counted while measuring
<link linkend="DTV-STAT-ERROR-BLOCK-COUNT"><constant>DTV_STAT_ERROR_BLOCK_COUNT</constant></link>.</listitem>
</itemizedlist>
</section>
</section>

<section id="frontend-property-terrestrial-systems">
<title>Properties used on terrestrial delivery systems</title>
<section id="dvbt-params">
Expand All @@ -871,6 +1039,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-HIERARCHY"><constant>DTV_HIERARCHY</constant></link></para></listitem>
<listitem><para><link linkend="DTV-LNA"><constant>DTV_LNA</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="dvbt2-params">
<title>DVB-T2 delivery system</title>
Expand All @@ -895,6 +1064,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-STREAM-ID"><constant>DTV_STREAM_ID</constant></link></para></listitem>
<listitem><para><link linkend="DTV-LNA"><constant>DTV_LNA</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="isdbt">
<title>ISDB-T delivery system</title>
Expand Down Expand Up @@ -948,6 +1118,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-ISDBT-LAYER-SEGMENT-COUNT"><constant>DTV_ISDBT_LAYERC_SEGMENT_COUNT</constant></link></para></listitem>
<listitem><para><link linkend="DTV-ISDBT-LAYER-TIME-INTERLEAVING"><constant>DTV_ISDBT_LAYERC_TIME_INTERLEAVING</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="atsc-params">
<title>ATSC delivery system</title>
Expand All @@ -961,6 +1132,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-MODULATION"><constant>DTV_MODULATION</constant></link></para></listitem>
<listitem><para><link linkend="DTV-BANDWIDTH-HZ"><constant>DTV_BANDWIDTH_HZ</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="atscmh-params">
<title>ATSC-MH delivery system</title>
Expand Down Expand Up @@ -988,6 +1160,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-ATSCMH-SCCC-CODE-MODE-C"><constant>DTV_ATSCMH_SCCC_CODE_MODE_C</constant></link></para></listitem>
<listitem><para><link linkend="DTV-ATSCMH-SCCC-CODE-MODE-D"><constant>DTV_ATSCMH_SCCC_CODE_MODE_D</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="dtmb-params">
<title>DTMB delivery system</title>
Expand All @@ -1007,6 +1180,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-INTERLEAVING"><constant>DTV_INTERLEAVING</constant></link></para></listitem>
<listitem><para><link linkend="DTV-LNA"><constant>DTV_LNA</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
</section>
<section id="frontend-property-cable-systems">
Expand All @@ -1028,6 +1202,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-INNER-FEC"><constant>DTV_INNER_FEC</constant></link></para></listitem>
<listitem><para><link linkend="DTV-LNA"><constant>DTV_LNA</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="dvbc-annex-b-params">
<title>DVB-C Annex B delivery system</title>
Expand All @@ -1043,6 +1218,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-INVERSION"><constant>DTV_INVERSION</constant></link></para></listitem>
<listitem><para><link linkend="DTV-LNA"><constant>DTV_LNA</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
</section>
<section id="frontend-property-satellital-systems">
Expand All @@ -1062,6 +1238,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-VOLTAGE"><constant>DTV_VOLTAGE</constant></link></para></listitem>
<listitem><para><link linkend="DTV-TONE"><constant>DTV_TONE</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
<para>Future implementations might add those two missing parameters:</para>
<itemizedlist mark='opencircle'>
<listitem><para><link linkend="DTV-DISEQC-MASTER"><constant>DTV_DISEQC_MASTER</constant></link></para></listitem>
Expand All @@ -1077,6 +1254,7 @@ enum fe_interleaving {
<listitem><para><link linkend="DTV-ROLLOFF"><constant>DTV_ROLLOFF</constant></link></para></listitem>
<listitem><para><link linkend="DTV-STREAM-ID"><constant>DTV_STREAM_ID</constant></link></para></listitem>
</itemizedlist>
<para>In addition, the <link linkend="frontend-stat-properties">DTV QoS statistics</link> are also valid.</para>
</section>
<section id="turbo-params">
<title>Turbo code delivery system</title>
Expand Down
2 changes: 1 addition & 1 deletion Documentation/DocBook/media/dvb/frontend.xml
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Original file line number Diff line number Diff line change
Expand Up @@ -230,7 +230,7 @@ typedef enum fe_status {
<entry align="char">The frontend has found a DVB signal</entry>
</row><row>
<entry align="char">FE_HAS_VITERBI</entry>
<entry align="char">The frontend FEC code is stable</entry>
<entry align="char">The frontend FEC inner coding (Viterbi, LDPC or other inner code) is stable</entry>
</row><row>
<entry align="char">FE_HAS_SYNC</entry>
<entry align="char">Syncronization bytes was found</entry>
Expand Down
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