[Dell] [Z9100] Supporting BCM PreEmphasis Settings for Optics

[sridhar-ravindran]

- What I did
Added support for setting Optics specific PreEmphasis Values in Z9100.
This is to make sure the devices are programmed correct PreEmphasis values, which will improve the link stability of the ports
This solution will be present, only until the SAI implementation is completed for Dynamic Pre-Emphasis Support
Support for Dynamic Insertion/Removal of optics is not implemented. It configures preEmphasis values for optics present during reload.

- How I did it

    modified:   platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-z9100.install
    modified:   platform/broadcom/sonic-platform-modules-dell/debian/platform-modules-z9100.postinst
    new file:   platform/broadcom/sonic-platform-modules-dell/z9100/scripts/qsfp_monitor
    new file:   platform/broadcom/sonic-platform-modules-dell/z9100/scripts/z9100_preemp_db.py
    new file:   platform/broadcom/sonic-platform-modules-dell/z9100/scripts/z9100_qsfp_monitor.py
    new file:   platform/broadcom/sonic-platform-modules-dell/z9100/systemd/z9100-qsfp-monitor.service

Z9100 starts the z9100-qsfp-monitor.service which while booting up calls
z9100_qsfp_monitor.py script.

z9100_qsfp_monitor.py will read the eeprom contents of the inserted optics for the Cable Length

Based on Cable length (750mm, 1m , 1.5m, 2m, 3m) the following setting will be programmed.
Supplier Part number Configuration AWG and length Premphasis Amplitude
Amphenol-FCI NDARHF-M201 1x-2x QSFP28 30 AWG 1M 0x006808 0x8
Amphenol-FCI NDARHF-M206 1x-2x QSFP28 30 AWG 1.5M 0x006808 0xb
Amphenol-FCI NDARHJ-M202 1x-2x QSFP28 26 AWG 2M 0x006808 0xb
Amphenol-FCI NDARHF-M205 1x-2x QSFP28 30 AWG 0.75M 0x006808 0x8
Amphenol-FCI NDARHJ-M203 1x-2x QSFP28 26AWG 3M 0x006808 0xe
Amphenol-FCI NDAAFJ-M203 1x – 1x QSFP28 26 AWG 3M 0x006808 0xe
Amphenol-FCI NDAAFF-M205 1x-1x QSFP28 30 AWG 0.75M 0x006808 0x8
Amphenol-FCI NDAAFF-M201 1x – 1x QSFP28 30 AWG 1M 0x006808 0x8
Amphenol-FCI NDAAFF-M206 1x-1x QSFP28 30 AWG 1.5M 0x006808 0xb
Amphenol-FCI NDAAFJ-M202 1x – 1x QSFP28 26 AWG 2M 0x006808 0xb
Amphenol-FCI NDARHJ-M206 1x-2x QSFP28 26 AWG 1.5M 0x006808 0xb

in the bcm chipset.
The Database for holding the preEmphasis Values is present in z9100_preemp_db.py
- How to verify it

Verified the settings using phy commands and eyescan

<Port_Name> can be xe0,ce0,xe24,ce16 etc

phy diag <Port_Name> eyescan type=4 ber_scan_mode=0 lane=1

phy <Port_Name> AMS_TX_CTL2r.0
phy <Port_Name> CL93N72_UT_CTL2r.0
phy <Port_Name> CL93N72_UT_CTL3r.0

phy <Port_Name> AMS_TX_CTL2r.1
phy <Port_Name> CL93N72_UT_CTL2r.1
phy <Port_Name> CL93N72_UT_CTL3r.1
- Description for the changelog

Configure PreEmphasis Settings on BCM based on inserted Optics

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