[U-Boot-Users] dynamic setting of CONFIG_SYS_CLK_FREQ

Wolfgang Denk
2004-04-22T17:14:34Z

In message <66FC73FC-9476-11D8-A48D-000393DBC2E8@motorola.com> you wrote:
> I was wondering if there where an examples in the current u-boot source
> tree in which CONFIG_SYS_CLK_FREQ was determined dynamically. I have a

Not exactly for CONFIG_SYS_CLK_FREQ - but the TQM8xxL boards contain
code to measure the input clock against the (known) 32kHz clock.

> system in which I can read a config register on the board to let me
> know if the CONFIG_SYS_CLK_FREQ is 66Mhz or 33Mhz. I was hoping to
> have the 16550 uart (and anything else) that needed CONFIG_SYS_CLK_FREQ
> grab it from a variable instead.

If you provide a suitable init fuction which sets the value in the
global data section eraly enough, you can probably shortcut the use
of CONFIG_SYS_CLK_FREQ.

> This is on an MPC85xx platform system.

...or any other.

Best regards,

Wolfgang Denk

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