From: Simon Glass Date: Fri, 10 Oct 2014 14:21:54 +0000 (-0600) Subject: x86: Display basic CPU information on boot X-Git-Tag: v2015.01-rc1~69^2~6 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=92cc94a1fe8e7a3ec78e993ea1ff1dd0bbaa5c36;p=u-boot x86: Display basic CPU information on boot Display the type of CPU (x86 or x86_64) when starting up. Signed-off-by: Simon Glass --- diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index 7a4de29824..8c1eacc0c0 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -275,3 +275,67 @@ void cpu_disable_paging_pae(void) : : "eax"); } + +static bool has_cpuid(void) +{ + unsigned long flag; + + asm volatile("pushf\n" \ + "pop %%eax\n" + "mov %%eax, %%ecx\n" /* ecx = flags */ + "xor %1, %%eax\n" + "push %%eax\n" + "popf\n" /* flags ^= $2 */ + "pushf\n" + "pop %%eax\n" /* eax = flags */ + "push %%ecx\n" + "popf\n" /* flags = ecx */ + "xor %%ecx, %%eax\n" + "mov %%eax, %0" + : "=r" (flag) + : "i" (1 << 21) + : "eax", "ecx", "memory"); + + return flag != 0; +} + +static bool can_detect_long_mode(void) +{ + unsigned long flag; + + asm volatile("mov $0x80000000, %%eax\n" + "cpuid\n" + "mov %%eax, %0" + : "=r" (flag) + : + : "eax", "ebx", "ecx", "edx", "memory"); + + return flag > 0x80000000UL; +} + +static bool has_long_mode(void) +{ + unsigned long flag; + + asm volatile("mov $0x80000001, %%eax\n" + "cpuid\n" + "mov %%edx, %0" + : "=r" (flag) + : + : "eax", "ebx", "ecx", "edx", "memory"); + + return flag & (1 << 29) ? true : false; +} + +int cpu_has_64bit(void) +{ + return has_cpuid() && can_detect_long_mode() && + has_long_mode(); +} + +int print_cpuinfo(void) +{ + printf("CPU: %s\n", cpu_has_64bit() ? "x86_64" : "x86"); + + return 0; +} diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index 2938087cc1..32930bd8c5 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -19,4 +19,11 @@ void cpu_enable_paging_pae(ulong cr3); */ void cpu_disable_paging_pae(void); +/** + * cpu_has_64bit() - Check if the CPU has 64-bit support + * + * @return 1 if this CPU supports long mode (64-bit), 0 if not + */ +int cpu_has_64bit(void); + #endif diff --git a/include/configs/coreboot.h b/include/configs/coreboot.h index 4b90dc205d..a65d89bddc 100644 --- a/include/configs/coreboot.h +++ b/include/configs/coreboot.h @@ -26,6 +26,7 @@ #define CONFIG_PHYSMEM #define CONFIG_SYS_EARLY_PCI_INIT #define CONFIG_DISPLAY_BOARDINFO_LATE +#define CONFIG_DISPLAY_CPUINFO #define CONFIG_DM #define CONFIG_CMD_DM