1 files changed, 132 insertions, 0 deletions

diff --git a/_ont/ont-huawei-ma5671a.md b/_ont/ont-huawei-ma5671a.md
index e7fb530..928ff38 100644
--- a/_ont/ont-huawei-ma5671a.md
+++ b/_ont/ont-huawei-ma5671a.md
@@ -102,6 +102,138 @@ For more info [XPONos partition layout](https://github.com/XPONos/linux_lantiq-f
 | mtd4 | 006d8077 | 00010000  | "rootfs"      |
 | mtd5 | 00410000 | 00010000  | "rootfs_data" |
 
+## EEPROM (I2C slave simulated EEPROM)
+The Huawei MA5671A does not have a physical EEPROM, the Falcon SOC emulates an EEPROM by exposing it on the I2C interface as required by the SFF-8472 specification.
+
+On the I2C interface there will be two memories of 256 bytes each at the addresses `1010000X (A0h)` and `1010001X (A2h)`, however in reality the memory available from the emulated EEPROM will be 640 bytes each but only the first 256 bytes will be exposed in the I2C interface.
+
+The Huawei MA5671A stores the content of the emulated EEPROM in U-Boot env variables to restore it after a reboot:
+
+- `EEPROM0 (A0h)` stored in U-Boot env variable `sfp_a0_low_128`
+- `EEPROM1 (A2h)` stored in U-Boot env variable `sfp_a2_info`
+
+### EEPROM0 layout
+
+| address   | size     | name                              | default value                                                                               | description                                                         |
+| --------- | -------- | --------------------------------- | ------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
+|           |          | **BASE ID FIELDS (SFF-8472)**     |                                                                                             |                                                                     |
+| 0         | 1        | Identifier                        | `0x03` (SFP)                                                                                | Type of transceiver                                                 |
+| 1         | 1        | Ext identifier                    | `0x04` (MOD_DEF 4)                                                                          | Additional information about the transceiver                        |
+| 2         | 1        | Connector                         | `0x01` (SC)                                                                                 | Type of media connector                                             |
+| 3-10      | 8        | Transceiver                       | `0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00`                                                   | Code for optical compatibility                                      |
+| 11        | 1        | Encoding                          | `0x03` (NRZ)                                                                                | High speed serial encoding algorithm                                |
+| 12        | 1        | Signaling Rate, Nominal           | `0x0C` (1.244Gbps)                                                                          | Nominal signaling rate                                              |
+| 13        | 1        | Rate Identifier                   | `0x00` (Not used)                                                                           | Type of rate select functionality                                   |
+| 14        | 1        | Length (SMF,km)                   | `0x14` (20 km)                                                                              | Link length supported for single-mode fiber, units of km            |
+| 15        | 1        | Length (SMF)                      | `0xC8` (200 x 100m)                                                                         | Link length supported for single-mode fiber, units of 100 m         |
+| 16        | 1        | Length (50 um, OM2)               | `0x00` (No support)                                                                         | Link length supported for 50 um OM2 fiber, units of 10 m            |
+| 17        | 1        | Length (62.5 um, OM1)             | `0x00` (No support)                                                                         | Link length supported for 62.5 um OM1 fiber, units of 10 m          |
+| 18        | 1        | Length copper cable               | `0x00` (No support)                                                                         | Link length supported for copper or direct attach cable, units of m |
+| 19        | 1        | Length (50 um, OM3)               | `0x00` (No support)                                                                         | Link length supported for 50 um OM3 fiber, units of 10 m            |
+| 20-35     | 16       | Vendor name                       | `0x48 0x55 0x41 0x57 0x45 0x49 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x20 ` (HUAWEI) | SFP vendor name (ASCII)                                             |
+| 36        | 1        | Transceiver                       | `0x00` (No support)                                                                         | Code for optical compatibility                                      |
+| 37-39     | 3        | Vendor OUI                        | `0x00 0x00 0x00` (No specified)                                                             | SFP vendor IEEE company ID                                          |
+| 40-55     | 16       | Vendor PN                         | `0x4D 0x41 0x35 0x36 0x37 0x31 0x41 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x20` (MA5671A) | Part number provided by SFP vendor (ASCII)                          |
+| 56-59     | 4        | Vendor rev                        | `0x30 0x30 0x30 0x30` (0000)                                                                | Revision level for part number provided by vendor (ASCII)           |
+| 60-61     | 2        | Wavelength                        | `0x05 0x1E` (1310nm TX)                                                                     | Laser wavelength                                                    |
+| 62        | 1        | Fibre Channel Speed 2             | `0x00` (No support)                                                                         | Transceiver's Fibre Channel speed capabilities                      |
+| 63        | 1        | CC_BASE                           |                                                                                             | Check code for Base ID Fields (addresses 0 to 62)                   |
+|           |          | **EXTENDED ID FIELDS (SFF-8472)** |                                                                                             |                                                                     |
+| 64-65     | 2        | Options                           | `0x00 0x1A` (TX DISABLE, TX FAULT, RX LOS)                                                  | Indicates which optional transceiver signals are implemented        |
+| 66        | 1        | Signaling Rate, max               | `0x00` (No specified)                                                                       | Upper signaling rate margin, units of %                             |
+| 67        | 1        | Signaling Rate, min               | `0x00` (No specified)                                                                       | Lower signaling rate margin, units of %                             |
+| 68-83     | 16       | Vendor SN                         | Unique in each SFP                                                                          | Serial number provided by vendor (ASCII)                            |
+| 84-91     | 8        | Date code                         | Unique in each SFP                                                                          | Vendor's manufacturing date code                                    |
+| 92        | 1        | Diagnostic Monitoring Type        | `0x68` (Digital diagnostic, Internally calibrated, Received average power type)             | Indicates which type of diagnostic monitoring is implemented        |
+| 93        | 1        | Enhanced Options                  | `0xE0` (Alarm/warning flags, soft TX_DISABLE control, soft TX_FAULT monitoring)             | Indicates which optional enhanced features are implemented          |
+| 94        | 1        | SFF-8472 Compliance               | `0x03` (Rev 10.2 of SFF-8472)                                                               | Indicates which revision of SFF-8472 the transceiver complies with  |
+| 95        | 1        | CC_EXT                            |                                                                                             | Check code for the Extended ID Fields (addresses 64 to 94)          |
+|           |          | **VENDOR SPECIFIC FIELDS**        |                                                                                             |                                                                     |
+| 96-127    | 32       | Vendor data                       | Not sure if it's unique or not                                                              | Vendor specifc data (ASCII)                                         |
+| 128-255   | 128      | Reserved                          | `0x00 0x00 0x00...`                                                                         | Reserved                                                            |
+|           |          | **EXTRA EEPROM FIELDS**           |                                                                                             | **Not exposed to I2C interface**                                    |
+| 256-639   | 384      | Reserved                          | `0x00 0x00 0x00...`                                                                         | Reserved                                                            |
+
+
+### EEPROM1 layout
+
+| address   | size     | name                              | default value                                                                               | description                                                         |
+| --------- | -------- | --------------------------------- | ------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
+|           |          | **DIAGNOSTIC AND CONTROL FIELDS** |                                                                                             |                                                                     |
+| 0-1       | 2        | Temp High Alarm                   | `0x5F 0x00` (95℃)                                                                          |                                                                     |
+| 2-3       | 2        | Temp Low Alarm                    | `0xCE 0x00` (-50℃)                                                                         |                                                                     |
+| 4-5       | 2        | Temp High Warning                 | `0x5A 0x00` (90℃)                                                                          |                                                                     |
+| 6-7       | 2        | Temp Low Warning                  | `0xD3 0x00` (-45℃)                                                                         |                                                                     |
+| 8-9       | 2        | Voltage High Alarm                | `0x8C 0xA0` (3.6V)                                                                          |                                                                     |
+| 10-11     | 2        | Voltage Low Alarm                 | `0x75 0x30` (3.0V)                                                                          |                                                                     |
+| 12-13     | 2        | Voltage High Warning              | `0x88 0xB8` (3.5V)                                                                          |                                                                     |
+| 14-15     | 2        | Voltage Low Warning               | `0x79 0x18` (3.1V)                                                                          |                                                                     |
+| 16-17     | 2        | Bias High Alarm                   | `0xAF 0xC8` (90mA)                                                                          |                                                                     |
+| 18-19     | 2        | Bias Low Alarm                    | `0x00 0x00` (0mA)                                                                           |                                                                     |
+| 20-21     | 2        | Bias High Warning                 | `0x88 0xB8` (70mA)                                                                          |                                                                     |
+| 22-23     | 2        | Bias Low Warning                  | `0x00 0x00` (0mA)                                                                           |                                                                     |
+| 24-25     | 2        | TX Power High Alarm               | `0x9B 0x82` (36dBm)                                                                         | Value expressed in watts subunits                                   |
+| 26-27     | 2        | TX Power Low Alarm                | `0x22 0xD0` (-1dBm)                                                                         | Value expressed in watts subunits                                   |
+| 28-29     | 2        | TX Power High Warning             | `0x7B 0x86` (34dBm)                                                                         | Value expressed in watts subunits                                   |
+| 30-31     | 2        | TX Power Low Warning              | `0x2B 0xD4` (0dBm)                                                                          | Value expressed in watts subunits                                   |
+| 32-33     | 2        | RX Power High Alarm               | `0x09 0xCF` (-6dBm)                                                                         | Value expressed in watts subunits                                   |
+| 34-35     | 2        | RX Power Low Alarm                | `0x00 0x0D` (-29dBm)                                                                        | Value expressed in watts subunits                                   |
+| 36-37     | 2        | RX Power High Warning             | `0x07 0xCB` (-7dBm)                                                                         | Value expressed in watts subunits                                   |
+| 38-39     | 2        | RX Power Low Warning              | `0x00 0x10` (-28dBm)                                                                        | Value expressed in watts subunits                                   |
+| 40-45     | 6        | MAC address                       | Unique in each SFP                                                                          | Contains the mac address of the SFP, it could also be empty         |
+| 46-55     | 10       | Reserved                          | `0x00 0x00 0x00...`                                                                         | Reserved                                                            |
+| 56-59     | 4        | RX_PWR(4) Calibration             | `0x00 0x00 0x00 0x00`                                                                       | 4th order RSSI calibration coefficient                              |
+| 60-63     | 4        | RX_PWR(3) Calibration             | `0x00 0x00 0x00 0x00`                                                                       | 3rd order RSSI calibration coefficient                              |
+| 64-67     | 4        | RX_PWR(2) Calibration             | `0x00 0x00 0x00 0x00`                                                                       | 2nd order RSSI calibration coefficient                              |
+| 68-71     | 4        | RX_PWR(1) Calibration             | `0x3F 0x80 0x00 0x00`                                                                       | 1st order RSSI calibration coefficient                              |
+| 72-75     | 4        | RX_PWR(0) Calibration             | `0x00 0x00 0x00 0x00`                                                                       | 0th order RSSI calibration coefficient                              |
+| 76-77     | 2        | TX_I(Slope) Calibration           | `0x01 0x00`                                                                                 | Slope for Bias calibration                                          |
+| 78-79     | 2        | TX_I(Offset) Calibration          | `0x00 0x00`                                                                                 | Offset for Bias calibration                                         |
+| 80-81     | 2        | TX_PWR(Slope) Calibration         | `0x01 0x00`                                                                                 | Slope for TX Power calibration                                      |
+| 82-83     | 2        | TX_PWR(Offset) Calibration        | `0x00 0x00`                                                                                 | Offset for TX Power calibration                                     |
+| 84-85     | 2        | T(Slope) Calibration              | `0x01 0x00`                                                                                 | Slope for Temperature calibration                                   |
+| 86-87     | 2        | T(Offset) Calibration             | `0x00 0x00`                                                                                 | Offset for Temperature calibration, in units of 256ths °C           |
+| 88-89     | 2        | V(Slope) Calibration              | `0x01 0x00`                                                                                 | Slope for VCC calibration                                           |
+| 90-91     | 2        | V(Offset) Calibration             | `0x00 0x00`                                                                                 | Offset for VCC calibration                                          |
+| 92-94     | 3        | Reserved                          | `0x00 0x00 0x00`                                                                            | Reserved                                                            |
+| 95        | 1        | CC_DMI                            |                                                                                             | Check code for Base Diagnostic Fields (addresses 0 to 94)           |
+| 96        | 1        | Temperature MSB                   |                                                                                             | Internally measured module temperature                              |
+| 97        | 1        | Temperature LSB                   |                                                                                             |                                                                     |
+| 98        | 1        | Vcc MSB                           |                                                                                             | Internally measured supply voltage in transceiver                   |
+| 99        | 1        | Vcc LSB                           |                                                                                             |                                                                     |
+| 100       | 1        | TX Bias MSB                       |                                                                                             | Internally measured TX Bias Current                                 |
+| 101       | 1        | TX Bias LSB                       |                                                                                             |                                                                     |
+| 102       | 1        | TX Power MSB                      |                                                                                             | Measured TX output power                                            |
+| 103       | 1        | TX Power LSB                      |                                                                                             |                                                                     |
+| 104       | 1        | RX Power MSB                      |                                                                                             | Measured RX input power                                             |
+| 105       | 1        | RX Power LSB                      |                                                                                             |                                                                     |
+| 106-109   | 4        | Optional Diagnostics              | `0xFF 0xFF 0xFF 0xFF` (No support)                                                          | Monitor Data for Optional Laser temperature and TEC current         |
+| 110       | 1        | Status/Control                    | `0x00` (No support)                                                                         | Optional Status and Control Bits                                    |
+| 111       | 1        | Reserved                          | `0x00`                                                                                      | Reserved                                                            |
+| 112-113   | 2        | Alarm Flags                       | `0x00 0x00` (No support)                                                                    | Diagnostic Alarm Flag Status Bits                                   |
+| 114       | 1        | Tx Input EQ control               | `0xFF` (No support)                                                                         | Tx Input equalization level control                                 |
+| 115       | 1        | Rx Out Emphasis control           | `0xFF` (No support)                                                                         | Rx Output emphasis level control                                    |
+| 116-117   | 2        | Warning Flags                     | `0x00 0x00` (No support)                                                                    | Diagnostic Warning Flag Status Bits                                 |
+| 118-119   | 2        | Ext Status/Control                | `0x00 0x00` (No support)                                                                    | Extended module control and status bytes                            |
+|           |          | **GENERAL USE FIELDS**            |                                                                                             |                                                                     |
+| 120-126   | 7        | Vendor Specific                   | `0x70 0x00 0x00 0x00 0x00 0x00 0x00`                                                        | Vendor specific memory addresses                                    |
+| 127       | 1        | Table Select                      | `0x00`                                                                                      | Optional Page Select                                                |
+|           |          | **USER WRITABLE EEPROM**          |                                                                                             |                                                                     |
+| 128-190   | 63       | Reserved                          | `0xFF 0xFF 0xFF...`                                                                         | Reserved                                                            |
+| 191-214   | 24       | GPON LOID or PLOAM                | Depends on the configuration of the SFP                                                     | GPON Logical ONU ID or PLOAM, depends on `GPON LOID/PLOAM switch`   |
+| 215-231   | 17       | GPON LPWD                         | Depends on the configuration of the SFP                                                     | GPON Logical Password                                               |
+| 232       | 1        | GPON LOID/PLOAM switch            | Depends on the configuration of the SFP                                                     | `0x01` to enable LOID, `0x02` to enable PLOAM                       |
+| 233-240   | 8        | GPON SN                           | Unique in each SFP                                                                          | GPON Serial Number (ME 256)                                         |
+| 241-247   | 7        | Reserved                          | `0xFF 0xFF 0xFF...`                                                                         | Reserved                                                            |
+| 248-255   | 8        | Vendor Control                    | `0xFF 0xFF 0xFF...` (Not used)                                                              | Vendor specific control functions                                   |
+|           |          | **EXTRA EEPROM FIELDS**           |                                                                                             | **Not exposed to I2C interface**                                    |
+| 256-511   | 256      | Unknown vendor specific           |                                                                                             | Probably not used in current SFPs                                   |
+| 512-531   | 20       | GPON Equipment ID                 |                                                                                             | GPON Equipment ID (ME 257), may not work in some firmwares          |
+| 532-535   | 4        | GPON Vendor ID                    |                                                                                             | GPON Vendor ID (ME 256 and more), may not work in some firmware     |
+| 536-639   | 104      | Reserved                          |                                                                                             | Reserved                                                            |
+
+{% include alert.html content="For more information, see the SFF-8472 Rev 10.2 specification." alert="Info" icon="svg-info" color="blue" %}
+
 ## List of firmwares and files
 
 {% include alert.html content="If the root procedure without tweezers is used, the firmware already on the Huawei Stick corresponds to rooted firmware in this list." alert="Info" icon="svg-info" color="blue" %}