From e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Fri, 28 Aug 2015 09:58:54 +0800 Subject: Add qemu 2.4.0 Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang --- qemu/roms/u-boot/doc/README.omap-reset-time | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 qemu/roms/u-boot/doc/README.omap-reset-time (limited to 'qemu/roms/u-boot/doc/README.omap-reset-time') 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. -- cgit 1.2.3-korg