CPM2 early console

Dan Malek dan at embeddedalley.com
Wed Sep 28 02:39:54 EST 2005

On Sep 27, 2005, at 10:11 AM, Kalle Pokki wrote:

> Is the alloc_bootmem() function in e.g. cpm_uart_allocbuf() supposed 
> to give non-cached memory? In my 8248 board it seems not to.

It provides cache coherent memory, whether it is cached or not
depends upon the capabilities of the cache controller and
peripherals.  On the 82xx, it is supposed to be cached.

>  Only using DPRAM as buffer storage allows booting to proceed without 
> hanging right in the beginning.

The only thing that would cause a problem is an
incorrect CPM configuration.

> Any ideas what can set the bootmem memory as cached?

All of memory is always cached on 82xx.  Which is fine
since the cache controller keeps the processor core
and peripherals coherent in hardware.


	-- Dan

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