How to Test SPI loopback on LS1046ardb with SD card boot mode

[ABCD3]

Hi,

Working with a LS1046ardb board, with the boot boot source set to SD card boot. I would like to test spi loopback functionality on this setup.

shorted SPI_MOSI and SPI_MISO lines (TP10 and TP12) on the ls1046ardb board. Following are the questions:

1. Noticed there are some changes required in SPI_EXT and SPI_BASE to "0" in RCW, with these changes can we still boot from SD card?

2. Can this be done in while board is running from SD card boot or should be different boot mode be selected?

3. Is there any recommended method for validating SPI loopback on LS1046ARDB?

Thank you in advance!!

[yipingwang]

SDR50 and DDR50 mode will not work, as these mode require SDHC_CLK_SYNC_OUT, SDHC_CLK_SYNC_IN signals. (Please have a look in design checklist.)
As Data[4:7] are muxed with SPI chip select signal so SDHC interface will work in 4 bit mode only.
Another interface signal SDHC_VS is not availble when RCW[SPI_EXT]= 000, so SDHC interface must work in default mode (Low speed mode)
Please refer Table 3-8 in LS1046ARM.

In summary, SD can be used in Default or High speed mode along with SPI OR eMMC in 4 bit can be used in Default/High/HS200 mode along with SPI.

So you can use booting from SD card, and you could use your current SPI validation mode.

[ABCD3]

Thank you for the reply @yipingwang!!  If I understand correctly, you mean to say we cannot test SPI loopback with ls1046ardb with sd card boot mode?since, as per the schematic of ls1046ardb VS line is used already!! Because, just changing the SPI_EXT=0, I am not seeing anything on console, is any other changes is required? Or we need custom board to do this?

Thank you

[yipingwang]

When enabling SPI on LS1046ARDB, SD card can work in the default mode.