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 <s...@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
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