GT25Q128EB-H register and OTP definition:

Normal Status Register (05h/01h, normal mode):
  Bit 7     SRP
  Bit 6     EBL
  Bit 5-2   BP3-BP0
  Bit 1     WEL (read-only status)
  Bit 0     WIP (read-only status)

OTP Status Register (05h/01h, after Enter OTP Mode 3Ah):
  Bit 7     OTP_LOCK (one-time, permanent)
  Bit 6     WXDIS
  Bit 5     HRSW
  Bit 4     4KBL
  Bit 3     TB
  Bit 2     Reserved
  Bit 1     WEL (read-only status)
  Bit 0     WIP (read-only status)

OTP:
  One 512-byte sector mapped to FFF000h-FFF1FFh while OTP mode is active.
  Setting bit 7 in OTP Status Register permanently locks the OTP sector.

Unique ID:
  A factory-programmed 96-bit value is read with 5Ah from SFDP address
  000080h-00008Bh using one dummy byte.