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Diffstat (limited to 'qemu/roms/u-boot/doc/README.omap-reset-time')
| -rw-r--r-- | qemu/roms/u-boot/doc/README.omap-reset-time | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/doc/README.omap-reset-time b/qemu/roms/u-boot/doc/README.omap-reset-time new file mode 100644 index 000000000..0c974baca --- /dev/null +++ b/qemu/roms/u-boot/doc/README.omap-reset-time @@ -0,0 +1,20 @@ +README on how reset time on OMAPs should be calculated + +CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC: +Most OMAPs' provide a way to specify the time for +which the reset should be held low while the voltages +and Oscillator outputs stabilize. + +This time is mostly board and PMIC dependent. Hence the +boards are expected to specify a pre-computed time +using the above option, (the details on how to compute +the value are given below) without which a default time +as specified by CONFIG_DEFAULT_OMAP_RESET_TIME_MAX_USEC +is used. + +The value for CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC +can be computed using a summation of the below 3 parameters +-1- Time taken by the Osciallator to stop and restart +-2- PMIC OTP time +-3- Voltage ramp time, which can be derived using the +PMIC slew rate and value of voltage ramp needed. |