[U-Boot-Users] dynamic setting of CONFIG_SYS_CLK_FREQ

[Wolfgang Denk]

In message <66FC73FC-9476-11D8-A48D-000393DBC2E8 at 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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