STi7105 hardware boot procedure

What we have learned

STi7105 starts execution at address 0x0000_0000, in little endian mode.
Boot from SPI flash: the flash is mapped to EMI address space at 0x0000_0000, determined by hardware pins.
The initialization process configures a bunch of registers, incl. clock and peripherals.
SH-4 CPU has two address modes, either 29bits or 32bits. The memory mapping for both modes is different.
As on-chip RAM is never found in documentation, we can assume that LMI DDR2 SDRAM is initialized before execution starts
...which probably initialized by hardware or BootROM.
The LMI is mapped at 0x0C00_0000 in 29bit mode, 0x4000_0000 in 32bit mode.
The Github repo contains board support for this specific board(GB620)
Red LED is P0_4, Green LED is P0_5