imx258 serial upload protocol

mkffm2k22 — Tue, 04 Jan 2022 10:30:17 GMT

Dear all,

I am investigating some imx258 boards where I don't understand the current state of the imx258 chip.

The boards should be virgin, so I am using the serial upload protocol to talk to the imx258.
Write Memory with len 4, address 0xB8001004 and value 0x0076E83f returns ack 0x12343412, followed by 0x128a8a12.

My understanding is that this is the correct response if the board has secure boot enabled (if not, I should see 0x56787856 and 0x128a8a12). I tried a couple of Read Memory commands, all of them failed, regardless of the address. Again, this is the expected behaviour for imx258 chips with secure boot enabled.

The problem is, however, that the boards are meant to be at factory defaults and secure boot should
be disabled. Do you have any idea what I could do to get more information about the imx258's state?

I tried uploading a firmware image that is signed and known to work on our boards. The upload works ok, the final Completed command returns 0x88888888 as expected. But the firmware does not start.
I then sent a Get Status after the Completed command, this returned four times 0x47 (SRK hash does not match the uploaded image).

Is it ok in general to send a Get Status command after a firmware upload and the final Completed command? In an error case as above, I get a status of the failed upload, But if the upload and the firmware verification worked ok, the firmware is now beeing run and the imx258 does not respond
to Get Status (or other serial upload protocol commands) any more. Is it ok to use a timeout of a final Get Status as indication that the firmware upload was successful?

Thanks in advance for your comments.

Re: imx258 serial upload protocol

Bio_TICFSL — Tue, 11 Jan 2022 14:04:35 GMT

Hello mkffm2k22,

You should receive address in ROM and not in DDR, please check it:

https://www.nxp.com/docs/en/application-note/AN4547.pdf

Regards

i.MX ProcessorsのトピックRe: imx258 serial upload protocol

imx258 serial upload protocol

Re: imx258 serial upload protocol