I develope custom board for our application and I am using Xavier NX emmc som in that.
In that carrier board I provide PCIe four lane M.2 socket for SSD connection.
I follow same schematic as given in Xavier NX devkit.
But unfortunately when I connect SSD in my board SOM is not booting up properly.
Please check attached excel file where I have given comparison of booting debug log of Devkit with and without SSD and Custom board booting debug log with and without SSD.
From observation it look like SOM is detecting the PCIe device but its not able to get its ID and other details.
Generally I have observe that along with PCIe lane there has to be I2C lane but in devkit there is no I2C communication between PCIe device and SOM.
Please guide me on this. NVME Log.xlsx (88.0 KB)
Thanks a lot for reply.
Can you please confirm one thing that whether we require I2C interface along with PCIe lane while SOM interface with external SSD?
If you check Xavier NX devkit schematic there I2C2 is routed to M.2 socket through jumper but I dont know whether its connected or not.
Please guide me on this.
Please find attached our custom boards schematic.
Here only one difference was there that M.2 ALERT pin previously I connected to GPIO 10 but as per devkit schematic I changed its connections to SDIO_D1 pin (221).
But still when I connect SSD to SOM board ,SOM start booting but its not finishing its booting.
I think its engaged in some loop. SOM CONNECTION_2.pdf (510.9 KB) NVME M2.pdf (316.8 KB)
I was slightly confused that whether I2C2 is connected to SSD or not.
Because I2C2 already implemented for EEPROM communication.
In my custom board I have not include EEPROM.
I just want to know that is there any role of I2C in SSD communication?
Please give feed back on this.