-----Original Message----- From: coreboot-bounces@coreboot.org [mailto:coreboot-bounces@coreboot.org] On Behalf Of Patrick Georgi Sent: Wednesday, November 10, 2010 02:46 AM To: coreboot@coreboot.org Subject: Re: [coreboot] [PATCH] Avoid hang when 4GB or more DRAM is installed on AMD RS780 UMA systems
] Maybe move amd_setup_var_mtrrs to src/cpu/amd/mtrr/amd_mtrr.c, too?
Hello Patrick,
Moving amd_setup_var_mtrrs to amd_mtrr.c can be done. But amd_setup_var_mtrrs relies on three static functions in mtrr.c. These three functions would have to be make public: range_to_mtrr, set_var_mtrr, enable_var_mtrr. If that is OK I can give it a try.
Another possibility is to go back to the idea of one x86_setup_var_mtrrs function. A new flag could be passed to x86_setup_var_mtrrs that tells tells the function that it ius running on an AMD system.
It is a little frustrating to have to worry about the possibility of a code change breaking non-AMD UMA operation when I have no way to test it. For example, I suspect the UMA logic for > 4GB systems is not working for all systems. While I can confirm this for AMD systems, I cannot confirm it for non-AMD systems. So I assume I must use one method or another to preserve the existing logic for non-AMD use, just in case it really does work for UMA systems with more than 4GB DRAM.
Thnaks, Scott
]Patrick