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path: root/src/cpu/x86/car/cache_as_ram_post.c
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Diffstat (limited to 'src/cpu/x86/car/cache_as_ram_post.c')
-rw-r--r--src/cpu/x86/car/cache_as_ram_post.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/src/cpu/x86/car/cache_as_ram_post.c b/src/cpu/x86/car/cache_as_ram_post.c
new file mode 100644
index 0000000000..8cbc1e9cba
--- /dev/null
+++ b/src/cpu/x86/car/cache_as_ram_post.c
@@ -0,0 +1,82 @@
+
+ __asm__ volatile (
+ /*
+ FIXME : backup stack in CACHE_AS_RAM into mmx and sse and after we get STACK up, we restore that.
+ It is only needed if we want to go back
+ */
+
+ /* We don't need cache as ram for now on */
+ /* disable cache */
+ "movl %cr0, %eax\n\t"
+ "orl $(0x1<<30),%eax\n\t"
+ "movl %eax, %cr0\n\t"
+
+ /* clear sth */
+ "movl $0x200, %ecx\n\t"
+ "xorl %edx, %edx\n\t"
+ "xorl %eax, %eax\n\t"
+ "wrmsr\n\t"
+ "movl $0x201, %ecx\n\t"
+ "wrmsr\n\t"
+
+ /* enable fast string operation */
+ "movl $0x1a0, %ecx\n\t"
+ "rdmsr\n\t"
+ "orl $1, %eax\n\t"
+ "wrmsr\n\t"
+
+#if defined(CLEAR_FIRST_1M_RAM)
+ /* enable caching for first 1M using variable mtrr */
+ "movl $0x200, %ecx\n\t"
+ "xorl %edx, %edx\n\t"
+ "movl $(0 | 1), %eax\n\t"
+// "movl $(0 | MTRR_TYPE_WRCOMB), %eax\n\t"
+ "wrmsr\n\t"
+
+ "movl $0x201, %ecx\n\t"
+ "movl $0x0000000f, %edx\n\t" /* AMD 40 bit 0xff*/
+ "movl $((~(( 0 + 0x100000) - 1)) | 0x800), %eax\n\t"
+ "wrmsr\n\t"
+#endif
+
+ /* enable cache */
+ "movl %cr0, %eax\n\t"
+ "andl $0x9fffffff,%eax\n\t"
+ "movl %eax, %cr0\n\t"
+#if defined(CLEAR_FIRST_1M_RAM)
+ /* clear the first 1M */
+ "movl $0x0, %edi\n\t"
+ "cld\n\t"
+ "movl $(0x100000>>2), %ecx\n\t"
+ "xorl %eax, %eax\n\t"
+ "rep stosl\n\t"
+
+ /* disable cache */
+ "movl %cr0, %eax\n\t"
+ "orl $(0x1<<30),%eax\n\t"
+ "movl %eax, %cr0\n\t"
+
+ /* enable caching for first 1M using variable mtrr */
+ "movl $0x200, %ecx\n\t"
+ "xorl %edx, %edx\n\t"
+ "movl $(0 | 6), %eax\n\t"
+// "movl $(0 | MTRR_TYPE_WRBACK), %eax\n\t"
+ "wrmsr\n\t"
+
+ "movl $0x201, %ecx\n\t"
+ "movl $0x0000000f, %edx\n\t" /* AMD 40 bit 0xff*/
+ "movl $((~(( 0 + 0x100000) - 1)) | 0x800), %eax\n\t"
+ "wrmsr\n\t"
+
+ /* enable cache */
+ "movl %cr0, %eax\n\t"
+ "andl $0x9fffffff,%eax\n\t"
+ "movl %eax, %cr0\n\t"
+ "invd\n\t"
+
+ /*
+ FIXME: I hope we don't need to change esp and ebp value here, so we can restore value from mmx sse back
+ But the problem is the range is some io related, So don't go back
+ */
+#endif
+ );