i2p/haiku-beta6
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

When clearing the MTRRs also set the default type to uncacheable. Otherwise on

Browse Source 
systems where the default is set to a cachable type and MTRRs are used to define
the uncacheable areas, everything would become cacheable after clearing them.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@31026 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Michael Lotz
2009-06-13 11:35:57 +00:00
parent 581708b997
commit 96b24aef3f
1 changed files with 5 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/add-ons/kernel/cpu/x86/generic_x86.cpp
+5 -1
View File
@@ -101,8 +101,12 @@ generic_init_mtrrs(uint32 count)
// but turn on variable MTRR functionality // but turn on variable MTRR functionality
// we need to ensure that the default type is uncacheable, otherwise
// clearing the mtrrs could result in ranges that aren't supposed to be
// cacheable to become cacheable due to the default type
x86_write_msr(IA32_MSR_MTRR_DEFAULT_TYPE, x86_write_msr(IA32_MSR_MTRR_DEFAULT_TYPE,
x86_read_msr(IA32_MSR_MTRR_DEFAULT_TYPE) | IA32_MTRR_ENABLE); (x86_read_msr(IA32_MSR_MTRR_DEFAULT_TYPE) & ~0xff) | IA32_MTRR_ENABLE);
} }