On Fri, Sep 10, 2010 at 01:56:08PM +0800, hacklu wrote: > I didn't understand the address mask. > it's said that: BR[BA] is the base address,the OR[AM] is the address mask, ... > for instance, if my BR0[BA]=0111_0000_0000_0000_0, OR0[AM]=1111_1111_1111 > if I want to access the 0x70000000 or the 0x71000001.what address calculate > will be taken?
Assuming that BR0 is set to valid, the right chip select machine is selected, etc., my understanding of MPC885RM is: * 0x70000000 & OR0[AM] = 0x70000000 0x70000000 == BR0[BA] => CS0 active, 0x0000 on the address bus (haven't checked the actual bus width). * 0x71000001 & OR0[AM] = 0x71000000 0x71000000 != BR0[BA] => CS0 inactive, will check the following BR/ORs With kind regards, -- Baurzhan Ismagulov http://www.kz-easy.com/ _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
