How did i debug u-boot.bin from JTAG

Hi,

Read this wiki: http://processors.wiki.ti.com/index.php/Sitara_Linux_Training:_uboot_linux_debug_with_ccsv5

Hello Biser,

I Use UART0 to download the uboot.bin on the nor flash, the commands from a u-boot prompt to flash the board:
U-Boot# protect off all
U-Boot# erase all
U-Boot# loadb 0x82000000 u-boot.bin
U-Boot# cp.b 0x82000000 0x08000000 0x80000
U-Boot# protect on all

I am trying to boot AM3352 using NOR flash(Non-muxed,16bits) in "Fast External Booting" mode SYSBOOT[4:0]=11111b.
the boot process i use the LCD_DATA1 ~ LCD_DATA11 pins(Pin used for XIP_MUX2 mode) .
But it doesn't work properly in case of "Fast External Boot" settings,I don't know what reason is caused.

Best Regards

Section 26.1.6.1 from the AM335X TRM Rev. L specifies:

- Addr/Data muxed device or a non-muxed (selected using SYSBOOT[11:10]) device

- Bus width selected by SYSBOOT[8]

What are your SYSBOOT settings on these pins? Also, since LCD_DATA are both used as SYSBOOT and XIP_MUX2 pins, please check that they are at the desired SYSBOOT values at reset release time.

Hi Biser, Below is the SYSBOOT[15:0] pin setting.0100 0001 0101 1111
I check SYSBOOT values which is right.
but the commands from a u-boot prompt to flash the board:U-Boot# go 0x08000000
it can work properly ,then I Switch to Fast External Booting,but it is fail.
I check the Tracing Vectors from JTAG ,• 0x4030CE40 = 0xADC2F2BB
• 0x4030CE44 = 0xB25768BC• 0x4030CE48 = 0x93FB3505
I don't know what these mean. Please give guidance,thanks!

For the trace vector values please check section 26.1.12 from the AM335X TRM Rev. L. Table 26-41 shows what each bit means.

Are you enabling the OCMC RAM that starts at 0x40300000? For Fast XIP, early in u-boot you have to enable a CM_ register and a PM_ register. Forl regular XIP boot the boot ROM does this.

Steve K.

hi Steve,Thank you for your reply,
but how do i enable the OCMC RAM that starts at 0x40300000? introducing the OCMC RAM is very few,can you give me an example?
Best Regards

hi Steve,
I can only see a short read and CS sigal from oscilloscope when board is starting .
it seems to stop in assembly code of starting. but I don't know where.

I do not have any examples. But take a look at the CM_PER_OCMCRAM_CLKCTRL register in the TRM. I think you need to set the lower two bits to 2 and then loop to make sure the bits are set. That enables the clock. There might be more bits in other registers, but I am not sure.

Steve K.