gxfb/lxfb: detect framebuffer size using an MSR if VSA2 isn't available
If there's no VSA2 (ie, if we're using tinybios or OpenFirmware), use the
GLIU's P2D Range Offset Descriptor to determine how much memory we have
available for the framebuffer.
Originally based on a patch by Jordan Crouse. Tested with OpenFirmware;
Pascal informs me that tinybios has a stub that fills in P2D_RO0.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-x86/geode.h b/include/asm-x86/geode.h
index 4fb2f62..7154dc4 100644
--- a/include/asm-x86/geode.h
+++ b/include/asm-x86/geode.h
@@ -30,6 +30,8 @@
/* MSRS */
+#define MSR_GLIU_P2D_RO0 0x10000029
+
#define MSR_LX_GLD_MSR_CONFIG 0x48002001
#define MSR_LX_MSR_PADSEL 0x48002011 /* NOT 0x48000011; the data
* sheet has the wrong value */