From d32bb116f063d04e0c5f72e6fd0367d6e542c9fb Mon Sep 17 00:00:00 2001
From: Nico Huber <nico.h@gmx.de>
Date: Sun, 11 Oct 2020 22:32:58 +0200
Subject: [PATCH] libpayload/x86: Add some more CPUID helpers
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Change-Id: Ic88defd30c6d3791a51b78a14135aff55e89394d
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46285
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
---
 payloads/libpayload/include/x86/arch/cpuid.h | 32 ++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/payloads/libpayload/include/x86/arch/cpuid.h b/payloads/libpayload/include/x86/arch/cpuid.h
index 83733016fe..c77be9cff2 100644
--- a/payloads/libpayload/include/x86/arch/cpuid.h
+++ b/payloads/libpayload/include/x86/arch/cpuid.h
@@ -32,4 +32,36 @@
 #define cpuid(fn, eax, ebx, ecx, edx) \
 	asm("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) : "0"(fn))
 
+#define _declare_cpuid(reg)					\
+	static inline unsigned int cpuid_##reg(unsigned int fn)	\
+	{							\
+		unsigned int eax, ebx, ecx, edx;		\
+		cpuid(fn, eax, ebx, ecx, edx);			\
+		return reg;					\
+	}
+
+_declare_cpuid(eax)
+_declare_cpuid(ebx)
+_declare_cpuid(ecx)
+_declare_cpuid(edx)
+
+#undef _declare_cpuid
+
+static inline unsigned int cpuid_max(void)
+{
+	return cpuid_eax(0);
+}
+
+static inline unsigned int cpuid_family(void)
+{
+	const unsigned int eax = cpuid_eax(1);
+	return (eax & 0xff00000) >> (20 - 4) | (eax & 0xf00) >> 8;
+}
+
+static inline unsigned int cpuid_model(void)
+{
+	const unsigned int eax = cpuid_eax(1);
+	return (eax & 0xf0000) >> (16 - 4) | (eax & 0xf0) >> 4;
+}
+
 #endif