ranting about PI's CSI-2 port-pinout & CSI-2 versions

[/RaspberryPi]

Hi,
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my main question/rant is why Raspberry Pi foundation didn't implement recent/newer versions of CSI-2 ?
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(i am not talking about CSI-3 vs CSI-2, CSI-3 seems bi-directional & CSI-2 seems uni, CSI-2's purpose on Pi is for only capturing/input, so CSI-2 is fine)
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Pi4B & CM4 has CSI-2 v1.1 which was released/announced in 2013
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Also on this note, why does Pi4B board have 15-pin CSI-2 port, whereas CM4 has 22-pin port-support ?
22-pin CSI-2 port doubles (2x) the bandwidth of 15-pin port, because 22-pin port provide 4 lanes of CSI-2, whereas 15-pin port only has 2 lanes of CSI-2
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Bandwidth numbers :
CSI-2 v1.1 released in 2013
only provides max 6Gbps (theoretical) bandwidth with 1.5Gbps x 4 lanes, in case of CM4 (half in Pi4B, because half the number of lanes) via D-PHY v1.1
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CSI-2 v1.2 released in 2014
could provide 10Gbps (theoretical) bandwidth with 2.5Gbps x 4 lanes via D-PHY v1.2
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CSI-2 v1.3 released in 2015
could provide 22.8Gbps (theoretical) bandwidth with 5.7Gbps x 4 lanes via C-PHY v1.0
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I have attached some links regarding this topic,-
CSI-2 versions - https://www.mipi.org/sites/default/files/csi-2v4-chart-800.png
CSI-2 specification and D-PHY, C-PHY brief - https://www.mipi.org/sites/default/files/MIPI_CSI-2_Specification_Brief.pdf
release date of different versions - https://www.arasan.com/product/mipi/csi/csi2-v1-2-to-v2-1-
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All of this is came to my knowledge when I was going thorough the PiKVM rabbit-hole
If we (or only me?) want to capture 2560x1440 120fps signal we need CSI-2 port with the bandwidth-need of 14.4Gbps (i.e., HDMI 2.0b port bandwidth)
Also, for those who would suggest capture dongles (USB), USB ports on Pi are only 4-5Gbps & I read somewhere that CSI-2 has less overhead or something
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I can only hope that the future Pi (5?) have the specs for my need
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I will be posting this in Pi forums & Pi sub-reddit, will add links in edit,
https://forums.raspberrypi.com/viewtopic.php?t=337825
Thanks

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