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/* Check if CPU has some minimum CPUID bits
This runs in 16bit mode so that the caller can still use the BIOS
to output errors on the screen */
#include <asm/cpufeature.h>
verify_cpu:
pushfl # Save caller passed flags
pushl $0 # Kill any dangerous flags
popfl
#if CONFIG_X86_MINIMUM_CPU_MODEL >= 4
pushfl
orl $(1<<18),(%esp) # try setting AC
popfl
pushfl
popl %eax
testl $(1<<18),%eax
jz bad
#endif
#if REQUIRED_MASK1 != 0
pushfl # standard way to check for cpuid
popl %eax
movl %eax,%ebx
xorl $0x200000,%eax
pushl %eax
popfl
pushfl
popl %eax
cmpl %eax,%ebx
pushfl # standard way to check for cpuid
popl %eax
movl %eax,%ebx
xorl $0x200000,%eax
pushl %eax
popfl
pushfl
popl %eax
cmpl %eax,%ebx
jz bad # REQUIRED_MASK1 != 0 requires CPUID
movl $0x0,%eax # See if cpuid 1 is implemented
cpuid
cmpl $0x1,%eax
jb bad # no cpuid 1
movl $0x1,%eax # Does the cpu have what it takes
cpuid
#if CONFIG_X86_MINIMUM_CPU_MODEL > 4
#error add proper model checking here
#endif
andl $REQUIRED_MASK1,%edx
xorl $REQUIRED_MASK1,%edx
jnz bad
#endif /* REQUIRED_MASK1 */
popfl
xor %eax,%eax
ret
bad:
popfl
movl $1,%eax
ret
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