Use Of Bootloader In SoC Design Life Cycle

Use of bootloader, in SoC design.
SoC in simple terms is collection of required blocks, like USB, MAC, PCI, surrounded to the CPU (generally RISC CPU, ARM).
As a part of SoC development each hardware block is validated for its functionality.
Validation is done register level. Example if we want to test functionality provided by MAC block in our SoC, then these functionality are validated by writing test cases in bootloader (u-boot-1.1.6).
Bootloader will create an environment for the test cases. The test cases are added as commands for each block with different subtests for each block to touch the corner conditions.
To start with U-boot provides generic block test cases, like I2C and many more are getting added day by day.
Format of bootloader commands

int do_hello (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
printf("Hello World\n");
}


U_BOOT_CMD(
hello, 5, 0, do_hello,
" hello - Prints hello world\n",
" hello - Prints hello world\n"
" \n" \
);

this will register "hello" as command in bootloader commands list.
Using this structure To validate simple GPIO functionality we write GPIO related test cases, so as to test GPIO features like GPIO interrupt.

MAC Block Validation test cases could be

1. Link Up/Down test
2. a. Validates PHY interface.
3. b. Validates link negotiated by PHY
4. Link Interrupt test
5. a. Validatess the Link interrupt
6. Digital loop-back test in full duplex mode
7. a. Validates data path in MAC controller in varous link speeds
8. 10/100/1000Mbps
9. b. Validates normal frames (60-1514)
10. Analog Loop-back in full duplex mode
11. a. Validates PHY interface
12. b. Validates Data path in MAC as well as PHY
13. External loop-back test
14. a. Validates PHY interface
15. b. Validates Data path in MAC as well as PHY
16. Digital Loop-back test in half duplex mode
17. a. Validates data path in MAC controller
18. DMA interrupt test
19. a. Validates th MAC interrupts
20. Incremental test
21. a. Validates Data pathin MAC controller for varrying packet length
22. External Incremental test
23. a. Validates Data path in MAC controller and PHY for varrying packet length
24. Promiscuous and MIB
25. a. Validates Promiscous and Normal mode
26. b. Validates the statistic count registers
27. Pause Frame test
28. a. Validates Pause frame Transmit and recieve
29. b. Validates the statistic count registers
30. Multicast frame test
31. a. Validates the Hash table entry for Multicast filter
32. b. Validates drop and pass of a Multicast Frame
33. c. Validates the statistic count registers