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Lokesh Vutla0b1b60c2013-04-17 20:49:40 +00001README on how reset time on OMAPs should be calculated
2
3CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC:
4Most OMAPs' provide a way to specify the time for
5which the reset should be held low while the voltages
6and Oscillator outputs stabilize.
7
8This time is mostly board and PMIC dependent. Hence the
9boards are expected to specify a pre-computed time
10using the above option, (the details on how to compute
11the value are given below) without which a default time
12as specified by CONFIG_DEFAULT_OMAP_RESET_TIME_MAX_USEC
13is used.
14
15The value for CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC
16can 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
20PMIC slew rate and value of voltage ramp needed.