README: document the requirements for CONFIG_SYS_HZ

CONFIG_SYS_HZ must be 1000, and get_timer() must therefore return ms.
Document this.

README text provided by Tom Rini.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
This commit is contained in:
Stephen Warren 2013-03-27 17:06:41 +00:00 committed by Tom Rini
parent b343bbb528
commit 795659dc1c

7
README
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@ -496,6 +496,13 @@ The following options need to be configured:
exists, unlike the similar options in the Linux kernel. Do not exists, unlike the similar options in the Linux kernel. Do not
set these options unless they apply! set these options unless they apply!
- CPU timer options:
CONFIG_SYS_HZ
The frequency of the timer returned by get_timer().
get_timer() must operate in milliseconds and this CONFIG
option must be set to 1000.
- Linux Kernel Interface: - Linux Kernel Interface:
CONFIG_CLOCKS_IN_MHZ CONFIG_CLOCKS_IN_MHZ