Add file-backed implementation to allow users to assign an OTP image
file to machine. If '-boot otp-file=filename' is specified, OTP
device uses otp image file instead of fuse array. In order to keep data
up-to-date due to unexpected crash or CTRL+a-x, every read/write to OTP
memory involves file open, mmap and close operation to the image file.
Add write-once feature to block second write operation to the OTP
memory. Only keep the 'written' state for non-control register range
from 0x38 to 16KB.
Tested on sifive_u for both qemu and u-boot.
Green Wan (2):
hw/riscv: sifive_u: Add file-backed OTP. softmmu/vl: add otp-file to
boot option
hw/riscv: sifive_u: Add write-once protection.
hw/riscv/sifive_u_otp.c | 122 ++++++++++++++++++++++++++++++--
include/hw/riscv/sifive_u_otp.h | 3 +
qemu-options.hx | 3 +-
softmmu/vl.c | 6 +-
4 files changed, 128 insertions(+), 6 deletions(-)
--
2.17.1
