6441 2014-06-13 05:24:11 +0000 Minnowboard UEFI + SpiDeviceDxe driver doesnot remove SPI Write Protection 2014-06-13 09:27:30 +0000 1 1 12 Hardware Platforms MinnowBoard MAX Firmware minnowboard-uefi-firmware unspecified MinnowBoard x86 RESOLVED FIXED Undecided minor --- 1 vijaikumar.k vijaikumar.k scott.a.garman vijaikumar.k --- --- No (bug/feature does not impact docs) oldest_to_newest 43907 0 vijaikumar.k 2014-06-13 05:24:11 +0000 In Minnowboard UEFI we have got EFI_SPI_PROTOCOL, Inside IntelE6xxRuPkg/SpiDeviceDxe folder we have SpiDeviceDxe.c file. It has a function called InitSpiDevice which has the following line of code which claims to remove write protection in SPI flash chip. Status = mSpiProtocol->Execute ( mSpiProtocol, SPI_DEVICE_READ_STATUS_CMD_INDEX, SPI_FLASH_PART_OPCODE_WRITE_STATUS, SPI_DEVICE_PREFIX_OP_WRITE_S_EN_INDEX, TRUE, TRUE, TRUE, 0, sizeof (Data), &Data, EnumSpiRegionAll ); By default WinBond SPI Flash is Not write protected on powerup (i.e BP0 BP1 BP2 are zero). I tried writing some value (0x55) into the Status Register using the above API, when i read back I should get 54(depending on the BITs which are write only). But I get "02". It is not actually writing the required opcode to the SPI. 43908 1 vijaikumar.k 2014-06-13 05:29:18 +0000 We should pass the index of the opcode to be used to that API, here they have passed the opcode itself. The code should be as follows: Pass SPI_DEVICE_WRITE_STATUS_CMD_INDEX as 3rd argument instead of SPI_FLASH_PART_OPCODE_WRITE_STATUS Status = mSpiProtocol->Execute ( mSpiProtocol, SPI_DEVICE_READ_STATUS_CMD_INDEX, SPI_DEVICE_WRITE_STATUS_CMD_INDEX, SPI_DEVICE_PREFIX_OP_WRITE_S_EN_INDEX, TRUE, TRUE, TRUE, 0, sizeof (Data), &Data, EnumSpiRegionAll );