| #include <stdint.h> |
| #include <string.h> |
| #include <cpu.h> |
| |
| /** @file |
| * |
| * CPU identification |
| * |
| */ |
| |
| /** |
| * Test to see if CPU flag is changeable |
| * |
| * @v flag Flag to test |
| * @ret can_change Flag is changeable |
| */ |
| static inline int flag_is_changeable ( unsigned int flag ) { |
| uint32_t f1, f2; |
| |
| __asm__ ( "pushfl\n\t" |
| "pushfl\n\t" |
| "popl %0\n\t" |
| "movl %0,%1\n\t" |
| "xorl %2,%0\n\t" |
| "pushl %0\n\t" |
| "popfl\n\t" |
| "pushfl\n\t" |
| "popl %0\n\t" |
| "popfl\n\t" |
| : "=&r" ( f1 ), "=&r" ( f2 ) |
| : "ir" ( flag ) ); |
| |
| return ( ( ( f1 ^ f2 ) & flag ) != 0 ); |
| } |
| |
| /** |
| * Get CPU information |
| * |
| * @v cpu CPU information structure to fill in |
| */ |
| void get_cpuinfo ( struct cpuinfo_x86 *cpu ) { |
| unsigned int cpuid_level; |
| unsigned int cpuid_extlevel; |
| unsigned int discard_1, discard_2, discard_3; |
| |
| memset ( cpu, 0, sizeof ( *cpu ) ); |
| |
| /* Check for CPUID instruction */ |
| if ( ! flag_is_changeable ( X86_EFLAGS_ID ) ) { |
| DBG ( "CPUID not supported\n" ); |
| return; |
| } |
| |
| /* Get features, if present */ |
| cpuid ( 0x00000000, &cpuid_level, &discard_1, |
| &discard_2, &discard_3 ); |
| if ( cpuid_level >= 0x00000001 ) { |
| cpuid ( 0x00000001, &discard_1, &discard_2, |
| &discard_3, &cpu->features ); |
| } else { |
| DBG ( "CPUID cannot return capabilities\n" ); |
| } |
| |
| /* Get 64-bit features, if present */ |
| cpuid ( 0x80000000, &cpuid_extlevel, &discard_1, |
| &discard_2, &discard_3 ); |
| if ( ( cpuid_extlevel & 0xffff0000 ) == 0x80000000 ) { |
| if ( cpuid_extlevel >= 0x80000001 ) { |
| cpuid ( 0x80000001, &discard_1, &discard_2, |
| &discard_3, &cpu->amd_features ); |
| } |
| } |
| } |