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authorAndres Salomon2008-04-28 11:14:54 +0200
committerLinus Torvalds2008-04-28 17:58:35 +0200
commite9338364e6989ca2707638c7c70ae22975b0bb6c (patch)
treedd27e70a9804ee80abb28752b13c07b0ebe63dda
parentx86: geode: MSR cleanup (diff)
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x86: GEODE: add Virtual Systems Architecture detection
This is generic VSA2 detection. It's used by OLPC to determine whether or not the BIOS contains VSA2, but since other BIOSes are coming out that don't use the VSA (ie, tinybios), it might end up being useful for others. Signed-off-by: Andres Salomon <dilinger@debian.org> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jordan Crouse <jordan.crouse@amd.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--include/asm-x86/geode.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/include/asm-x86/geode.h b/include/asm-x86/geode.h
index b1bdf6378563..3978200f126c 100644
--- a/include/asm-x86/geode.h
+++ b/include/asm-x86/geode.h
@@ -103,6 +103,14 @@ extern int geode_get_dev_base(unsigned int dev);
#define PM_AWKD 0x50
#define PM_SSC 0x54
+/* VSA2 magic values */
+
+#define VSA_VRC_INDEX 0xAC1C
+#define VSA_VRC_DATA 0xAC1E
+#define VSA_VR_UNLOCK 0xFC53 /* unlock virtual register */
+#define VSA_VR_SIGNATURE 0x0003
+#define VSA_SIG 0x4132 /* signature is ascii 'VSA2' */
+
/* GPIO */
#define GPIO_OUTPUT_VAL 0x00
@@ -174,6 +182,17 @@ static inline int is_geode(void)
return (is_geode_gx() || is_geode_lx());
}
+/*
+ * The VSA has virtual registers that we can query for a signature.
+ */
+static inline int geode_has_vsa2(void)
+{
+ outw(VSA_VR_UNLOCK, VSA_VRC_INDEX);
+ outw(VSA_VR_SIGNATURE, VSA_VRC_INDEX);
+
+ return (inw(VSA_VRC_DATA) == VSA_SIG);
+}
+
/* MFGPTs */
#define MFGPT_MAX_TIMERS 8