| 1234567891011121314151617181920212223 |
- The current implementation allows the user to specify the desired CPU
- clock value, in MHz, via an environment variable "cpuclk".
- Three compile-time constants are used:
- CFG_866_OSCCLK - input quartz clock
- CFG_866_CPUCLK_MIN - minimum allowed CPU clock
- CFG_866_CPUCLK_MAX - maximum allowed CPU clock
- CFG_866_CPUCLK_DEFAULT - default CPU clock value
- If the "cpuclk" environment variable value is within the CPUCLK_MIN /
- CPUCLK_MAX limits, the specified value is used. Otherwise, the
- default CPU clock value is set.
- Please make sure you understand what you are doing, and understand
- the restrictions of your hardware (board, processor). For example,
- ethernet will stop working for CPU clock frequencies below 25 MHz.
- Please note that for now the new clock-handling code has been enabled
- for the TQM866M board only, even though it should be pretty much
- common for other MPC859 / MPC866 based boards also. Our intention
- here was to move in small steps and not to break the existing code
- for other boards.
|
