SYS_BOOT table in the TRM for AM35xx

Andy Jump53114

We've been attempting to strap the boot order for our AM35xx platform according to Table 24-4 in SPRUGR0B (the AM35xx TRM). We normally boot from XIP but also require the option to boot from UART during debug. The debug option is achieved using a header.

Based on this, the obvious strapping solution would be SYS_BOOT[5] set to '1' and SYS_BOOT[4:0] set to '10011' which according to the table makes UART the first boot device and XIP the second boot device.

When we strap this option we do not get either UART or XIP boot (a bootloader is already in the FLASH).

When we strap with SYS_BOOT[5] set to '1' and SYS_BOOT[4:0] set to '11100' we can boot from the UART.

When we strap SYS_BOOT[4:0] set to '11111' regardless of SYS_BOOT[5] we get XIP.

Is there an updated table available with the correct boot options?

Regards

Andy

ps can the table also be corrected to removed the mention of reduced pin mode for SYS_BOOT[8] - I believe this function is not supported and SYS_BOOT[8] has to be pulled down for the SDRC to function.

over 15 years ago

0 MATT GESSNER over 15 years ago

Expert 1435 points

Have you gotten a reply from anyone about this?

0 JJD over 15 years ago in reply to MATT GESSNER

TI__Guru* 95831 points

The tables should be correct. I can try to check the ones in question next week. You should be able to see what the ROM attempted to boot from by looking at the tracing vectors. Some info about them is in the Initialization chapter, and some explanation is found here (the information also applies to AM35x): http://processors.wiki.ti.com/index.php/OMAP35x_and_AM/DM37x_Initialization

Regards,

James

0 Jeff Culverhouse over 15 years ago

TI__Genius 9190 points

Hello Andy,

what is the system doing then you are set to UART then XIP (110011)? Are you getting anything out on the display? do you have a JTAG emulator that you can connect? If so, you could read the trace vectors to see how far along in the boot process you are getting. here is a wiki article on how to read the trace vectors.

http://processors.wiki.ti.com/index.php/OMAP35x_and_AM/DM37x_Initialization

The reason I ask for this is because I wonder if the ROM code is finding something on UART that looks like x-loader and it getting hung up there.

0 Andy Jump53114 over 15 years ago in reply to Jeff Culverhouse

Prodigy 130 points

Hi Jeff

I didn't get notified of previous posts on this subject hence the delay in replying.

We see nothing at all on the display. We use the same procedure for boot strapping (110011) and (111100) but only the second strapping works. We have a JTAG available within the Firmware group. I will try to get some of their time with it today and see what is being seen.

Andy

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SYS_BOOT table in the TRM for AM35xx