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1 README on how reset time on OMAPs should be calculated
2
3 CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC:
4 Most OMAPs' provide a way to specify the time for
5 which the reset should be held low while the voltages
6 and Oscillator outputs stabilize.
7
8 This time is mostly board and PMIC dependent. Hence the
9 boards are expected to specify a pre-computed time
10 using the above option, (the details on how to compute
11 the value are given below) without which a default time
12 as specified by CONFIG_DEFAULT_OMAP_RESET_TIME_MAX_USEC
13 is used.
14
15 The value for CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC
16 can be computed using a summation of the below 3 parameters
17 -1- Time taken by the Osciallator to stop and restart
18 -2- PMIC OTP time
19 -3- Voltage ramp time, which can be derived using the
20 PMIC slew rate and value of voltage ramp needed.