31 May
2003
31 May
'03
1:11 p.m.
Ron, please apply this patch. It should not break anything, and significantly speeds up booting of certain boards like EPIA.
This patch does two things:
- Add write-through cache for 0xf0000-0xfffff before uncompressing linuxbios_c, if option XIP_LOW is defined. - Changes existing XIP (execute in place) code to use write-through cache instead of write-protect cache. (as Eric suggested)
--
Takeshi
Index: earlymtrr.inc
===================================================================
RCS file: /cvsroot/freebios/freebios/src/cpu/p6/earlymtrr.inc,v
retrieving revision 1.4
diff -u -r1.4 earlymtrr.inc
--- earlymtrr.inc 8 Aug 2001 02:45:09 -0000 1.4
+++ earlymtrr.inc 31 May 2003 14:59:56 -0000
@@ -35,6 +35,22 @@
movl $0x06060606, %edx
movl $0x06060606, %eax
wrmsr
+
+#ifdef XIP_LOW
+ /* enable write through cache for 0xf0000-0xfffff*/
+ movl $MTRRfix4K_F0000_MSR, %ecx
+ rdmsr
+ movl $0x04040404, %edx
+ movl $0x04040404, %eax
+ wrmsr
+
+ movl $MTRRfix4K_F8000_MSR, %ecx
+ rdmsr
+ movl $0x04040404, %edx
+ movl $0x04040404, %eax
+ wrmsr
+#endif /* XIP_LOW */
+
#endif /* MEMORY_HOLE */
set_var_mtrr:
@@ -56,12 +72,12 @@
wrmsr
#if defined(XIP_ROM_SIZE) && defined(XIP_ROM_BASE)
- /* enable write protect caching so we can do execute in place
+ /* enable write through caching so we can do execute in place
* on the flash rom.
*/
movl $0x202, %ecx
xorl %edx, %edx
- movl $(XIP_ROM_BASE | 0x005), %eax
+ movl $(XIP_ROM_BASE | 0x004), %eax
wrmsr
movl $0x203, %ecx