Custom carrier "Ramcode = 2"

Autonomous Machines Jetson & Embedded Systems Jetson TX1
1

Hi,

I am in the process of getting our custom carrier working and working through the errors during boot, the first error I am seeing is:

[0000.170] [TegraBoot] (version 00.00.2014.50-mobile-d44d4bf0)
[0000.175] Processing in cold boot mode Bootloader 2
[0000.180] A02 Bootrom Patch rev = 63
[0000.183] Power-up reason: on button
[0000.186] No Battery Present
[0000.189] RamCode = 2
.
.
[0000.947] RamCode = 2
[0000.950] get_emc_table_offset: Can’t find emc-table node
[0000.955] LPDDR4 Training: Can’t find emc-table node
.
.
[ 0.343265] tegra210-emc 7001b000.memory-controller: can’t find emc table for ram-code 0x02
[ 0.343320] tegra210-emc 7001b000.memory-controller: Invalid table size 0
[ 0.343389] tegra210-emc: probe of 7001b000.memory-controller failed with error -22

These messages all seem to be related to Ramcode = 2. On my tx1 devkit Ramcode = 0 during boot.

Does anyone know what this means and how I might change it 0?

Thanks

Kyle.

2

Hi kyler,

Are you using Jetpack3.1 + custom carrier board? Have you modified the device tree?

Ram-code is read from register and each ram code # has a corresponding emc-table in memory-controller of dts.

3

Hi,

Yes, we are using Jetpack3.1 with a custom carrier board and custom device tree. Can the device tree affect what code is read from the registers?

Thanks

Kyle.

4

Hi,

Yes, we are using Jetpack3.1 with a custom carrier board and custom device tree. Can the device tree affect what code is read from the registers?

Thanks

Kyle.

5

Hi Kyler,

The ram code number is read from register and device tree would try to search corresponding emc-table. If there is no such table, it would return false.

May I ask how you configure your ram on carrier board?

6

Hi,

Ah, after looking at the TRM, it seems that UART1_TXD and UART1_RTS select the RAM code during boot, is there any documentation as to the difference in tables? I guess I can either change the pin states during boot or duplicate one of the tables into index 2.

Thanks

Kyle.

7

It would be better to review the design of board to see why ram-code is 2.

8

We have used an N-channel FET with a pull up as a level shifter on the TX line, it’s this that’s causing the RAM-code to be 2.

9

The root cause is the TX line on your board is wrongly pulled to high, which will make the ram code wrong. Please try to hold the TX line to low during boot.