Taking into account this topic:
viewtopic.php?f=5&t=421 there is no need OpenOCD & JTAG to unbrick carambola2. SPI FLASH chip can easily be programmed by the pins of J13 connector of the development board.
J13 pin10 - GND
J13 pin11 - SPI_CS ( to GND)
J13 pin12 - SPI_CLK
J13 pin13 - SPI_MOSI
J13 pin14 - SPI_MISO
J13 pin15 - RESET ( to GND)
J13 pin16 - 3.3V