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21 lines
811 B
Text
21 lines
811 B
Text
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README on how reset time on OMAPs should be calculated
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CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC:
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Most OMAPs' provide a way to specify the time for
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which the reset should be held low while the voltages
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and Oscillator outputs stabilize.
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This time is mostly board and PMIC dependent. Hence the
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boards are expected to specify a pre-computed time
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using the above option, (the details on how to compute
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the value are given below) without which a default time
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as specified by CONFIG_DEFAULT_OMAP_RESET_TIME_MAX_USEC
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is used.
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The value for CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC
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can be computed using a summation of the below 3 parameters
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-1- Time taken by the Osciallator to stop and restart
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-2- PMIC OTP time
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-3- Voltage ramp time, which can be derived using the
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PMIC slew rate and value of voltage ramp needed.
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