From: Gireesh Hiremath Gireesh.Hiremath@in.bosch.com
By adding update_avalibale flag we wanted control the increment of bootcount, update_available flag is set from user space when there is upgrade in software which allow to increment of bootcount, otherwise no increment in the bootcount. Update_available and bootcount will be cleared after every successful boot from user space
version byte to handle the version number. to provide backward compatibility initial version number is 2.
RTC second scratch register[32-bit]: -zero byte hold boot count value -first byte hold update available state -second byte hold version -third byte hold magic number
Gireesh Hiremath (1): am335x, guardian: software update available status is stored in AM3352 RTC scracth register
configs/am335x_guardian_defconfig | 1 + drivers/bootcount/Kconfig | 27 ++++++++++++-- drivers/bootcount/Makefile | 1 + drivers/bootcount/bootcount_nvmem.c | 57 +++++++++++++++++++++++++++++ 4 files changed, 83 insertions(+), 3 deletions(-) create mode 100644 drivers/bootcount/bootcount_nvmem.c