Question of Memory cache control

[suhg77]

I have some questions about memory cache contorl.

1. Is it differentthe way ofdisabling cache in 32bit mode from in 64bit mode ?

I knowwhen CR0.CD bit is set, cache disable in 32bit mode.

In 64bit mode is it different?

2. Is itsimilar that cache control in 32bit mode and 64bit mode?

please answer my question.

Have a nice day~!

[Intel_Software_Netw1]

Greetings from Intel Software NetworkSupport. We are forwarding your question to our engineering contacts and will let you know how they respond.

Adetailed discussion of memory cache control can also be found in Chapter 10 of the IA-32 Intel Architecture Software Developer's Manual, Volume 3: System Programming Guide (http://developer.intel.com/design/pentium4/manuals/index_new.htm#sdm_vol3).

Regards,

Lexi S.

Intel Software Network Support

http://www.intel.com/software

Contact us

Message Edited by intel.software.network.support on 11-15-2005 11:44 PM

[Intel_Software_Netw1]

Our engineers responded as follows:

There is no difference in disabling/controlling cache between 32-bit or 64-bit modes of operation.

There are possibly multiple levels (L1, L2 & L3) of cache that need to be disabled in theproper order to ensure that the valid cache lines are written back to DRAM. CR0 is used to disable the lowest level of cache. Other levels are disabled using either model specific registers in the CPU or possibly external registers in the chipset.

We hope this is helpful.

Regards,

Lexi S.

Intel Software Network Support

http://www.intel.com/software/

Message Edited by intel.software.network.support on 11-15-2005 11:44 PM