This fixes a FIXME in src/cpu/amd/mtrr/amd_mtrr.c and shuts up the
Linux kernel, which was previously complaining that the MTRR setup
is wrong, if the cpu supports more than CONFIG_CPU_ADDR_BITS bits of
address space.

Shamelessly copied from Linux arch/x86/kernel/cpu/mtrr/main.c

Signed-off-by: Tobias Diedrich <[email protected]>

---

Index: src/cpu/amd/mtrr/amd_mtrr.c
===================================================================
--- src/cpu/amd/mtrr/amd_mtrr.c (revision 5985)
+++ src/cpu/amd/mtrr/amd_mtrr.c (working copy)
@@ -1,5 +1,6 @@
 #include <console/console.h>
 #include <device/device.h>
+#include <arch/cpu.h>
 #include <cpu/x86/mtrr.h>
 #include <cpu/amd/mtrr.h>
 #include <cpu/x86/cache.h>
@@ -175,11 +176,13 @@
 
        enable_cache();
 
-       /* FIXME we should probably query the cpu for this
-        * but so far this is all any recent AMD cpu has supported.
-        */
        address_bits = CONFIG_CPU_ADDR_BITS; //K8 could be 40, and GH could be 
48
 
+       /* AMD specific MSR to query number of address bits */
+       if (cpuid_eax(0x80000000) >= 0x80000008) {
+               address_bits = cpuid_eax(0x80000008) & 0xff;
+       }
+
        /* Now that I have mapped what is memory and what is not
         * Setup the mtrrs so we can cache the memory.
         */


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