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

Hi Simon,

On Fri, Nov 7, 2014 at 4:19 AM, Simon Glass sjg@chromium.org wrote:

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@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

My previous patch (http://patchwork.ozlabs.org/patch/406636/) introduced these cpuid_xxx functions already. Would you consider merging the two patches?

Regards, Bin