Re: physical address space management

[Steve Woodford <scw%netbsd.org@localhost>]

On Friday 28 March 2008 21:03:29 David Young wrote:

> enum pmem_props {                     /* hardware implementation */
>         PMEM_P_WTHRU          = 0x01  /* MTRR */
>       , PMEM_P_WBACK          = 0x02  /* MTRR */
>       , PMEM_P_WCOMB          = 0x04  /* MTRR */
>       , PMEM_P_UNCACHED       = 0x08  /* MTRR, AMD Elan SC520 PAR */
>       , PMEM_P_PREFETCH       = 0x10  /* PCI bus bridge */
> };
> 
> enum pmem_type {
>       , PMEM_T_RAM            = 0x01
>       , PMEM_T_ROM            = 0x02
>       , PMEM_T_PCI            = 0x04
> };

There are additional properties you may wish to account for, such as 
databus width and address modifiers (e.g. VMEbus).

How would you represent endian issues? For example a PCIbus hooked up to 
a big-endian CPU?

Cheers, Steve