Hello, my board is designed by myself, using TDA4AL chip, our board uses spl emmc mode to test, just start using the following steps ,and switch to EMMC start successfully
=> mmc dev 0 1 switch to partitions #1, OK mmc0(part 1) is current device => fatload mmc 1 ${loadaddr} tiboot3.bin filename[tiboot3.bin] 443806 bytes read in 29 ms (14.6 MiB/s) => mmc write ${loadaddr} 0x0 0x400 MMC write: dev # 0, block # 0, count 1024 ... 1024 blocks written: OK => fatload mmc 1 ${loadaddr} tispl.bin filename[tispl.bin] 965852 bytes read in 52 ms (17.7 MiB/s) => mmc write ${loadaddr} 0x400 0x1000 MMC write: dev # 0, block # 1024, count 4096 ... 4096 blocks written: OK => fatload mmc 1 ${loadaddr} u-boot.img filename[u-boot.img] 1116028 bytes read in 58 ms (18.3 MiB/s) => mmc write ${loadaddr} 0x1400 0x2000 MMC write: dev # 0, block # 5120, count 8192 ... 8192 blocks written: OK => mmc partconf 0 1 1 1 => mmc bootbus 0 2 0 0
But repeat the step 2-3 times,There are no errors, the board switch to EMMC fails to start,There is no printing compared to the first time,We tried three boards and one didn't get up the first time
We use SD to enter the system, export EMMC boot0 through the following command, and we can find that there is data
j721s2-evm:~# dd if=/dev/mmcblk0boot0 of=boot0.hex bs=1M count=5 5+0 records in 5+0 records out 5242880 bytes (5.2 MB, 5.0 MiB) copied, 0.086184 s, 60.8 MB/s j721s2-evm:~# sync
We tested the EMMC clock and cmd pin at boot and found a signal, There is no signal change at the measurement data0 pin
It seems that EMMC does not return any data, our voltage test of EMMC is normal, how to analyze this situation? Is it caused by software read and write problems or hardware errors, can you provide some suggestions? Thank you so much