[U-Boot] [PATCH 07/39] x86: Add processor functions for cpuid and stack pointer

[Simon Glass]

Add some functions to access cpuid from C in various useful ways. Also
add a function to get the stack pointer and another to halt the CPU.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 arch/x86/include/asm/processor.h | 121 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 121 insertions(+)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index bb3172f..30d7d48 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -30,4 +30,125 @@ enum {
 
 #define X86_GDT_SIZE		(X86_GDT_NUM_ENTRIES * X86_GDT_ENTRY_SIZE)
 
+#ifndef __ASSEMBLY__
+
+static inline __attribute__((always_inline)) void cpu_hlt(void)
+{
+	asm("hlt");
+}
+
+struct cpuid_result {
+	uint32_t eax;
+	uint32_t ebx;
+	uint32_t ecx;
+	uint32_t edx;
+};
+
+/*
+ * Generic CPUID function
+ */
+static inline struct cpuid_result cpuid(int op)
+{
+	struct cpuid_result result;
+	asm volatile(
+		"mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%ebx, %%esi;"
+		"mov %%edi, %%ebx;"
+		: "=a" (result.eax),
+		  "=S" (result.ebx),
+		  "=c" (result.ecx),
+		  "=d" (result.edx)
+		: "0" (op)
+		: "edi");
+	return result;
+}
+
+/*
+ * Generic Extended CPUID function
+ */
+static inline struct cpuid_result cpuid_ext(int op, unsigned ecx)
+{
+	struct cpuid_result result;
+	asm volatile(
+		"mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%ebx, %%esi;"
+		"mov %%edi, %%ebx;"
+		: "=a" (result.eax),
+		  "=S" (result.ebx),
+		  "=c" (result.ecx),
+		  "=d" (result.edx)
+		: "0" (op), "2" (ecx)
+		: "edi");
+	return result;
+}
+
+static inline ulong cpu_get_sp(void)
+{
+	ulong result;
+
+	asm volatile(
+		"mov %%esp, %%eax"
+		: "=a" (result));
+	return result;
+}
+
+/*
+ * CPUID functions returning a single datum
+ */
+static inline unsigned int cpuid_eax(unsigned int op)
+{
+	unsigned int eax;
+
+	__asm__("mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%edi, %%ebx;"
+		: "=a" (eax)
+		: "0" (op)
+		: "ecx", "edx", "edi");
+	return eax;
+}
+
+static inline unsigned int cpuid_ebx(unsigned int op)
+{
+	unsigned int eax, ebx;
+
+	__asm__("mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%ebx, %%esi;"
+		"mov %%edi, %%ebx;"
+		: "=a" (eax), "=S" (ebx)
+		: "0" (op)
+		: "ecx", "edx", "edi");
+	return ebx;
+}
+
+static inline unsigned int cpuid_ecx(unsigned int op)
+{
+	unsigned int eax, ecx;
+
+	__asm__("mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%edi, %%ebx;"
+		: "=a" (eax), "=c" (ecx)
+		: "0" (op)
+		: "edx", "edi");
+	return ecx;
+}
+
+static inline unsigned int cpuid_edx(unsigned int op)
+{
+	unsigned int eax, edx;
+
+	__asm__("mov %%ebx, %%edi;"
+		"cpuid;"
+		"mov %%edi, %%ebx;"
+		: "=a" (eax), "=d" (edx)
+		: "0" (op)
+		: "ecx", "edi");
+	return edx;
+}
+#endif /* __ASSEMBLY__ */
+
 #endif
-- 
2.1.0.rc2.206.gedb03e5