From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat, 23 Feb 2013 03:22:52 +0000 (-0800)
Subject: Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c47f39e3b75e1138823984ad5079547c7a41b726;p=linux-beck.git

Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 microcode loading update from Peter Anvin:
 "This patchset lets us update the CPU microcode very, very early in
  initialization if the BIOS fails to do so (never happens, right?)

  This is handy for dealing with things like the Atom erratum where we
  have to run without PSE because microcode loading happens too late.

  As I mentioned in the x86/mm push request it depends on that
  infrastructure but it is otherwise a standalone feature."

* 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/Kconfig: Make early microcode loading a configuration feature
  x86/mm/init.c: Copy ucode from initrd image to kernel memory
  x86/head64.c: Early update ucode in 64-bit
  x86/head_32.S: Early update ucode in 32-bit
  x86/microcode_intel_early.c: Early update ucode on Intel's CPU
  x86/tlbflush.h: Define __native_flush_tlb_global_irq_disabled()
  x86/microcode_intel_lib.c: Early update ucode on Intel's CPU
  x86/microcode_core_early.c: Define interfaces for early loading ucode
  x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on AP
  x86/common.c: Make have_cpuid_p() a global function
  x86/microcode_intel.h: Define functions and macros for early loading ucode
  x86, doc: Documentation for early microcode loading
---

c47f39e3b75e1138823984ad5079547c7a41b726
diff --cc arch/x86/kernel/head_32.S
index 3c3f58a0808f,2f705307c8d8..73afd11799ca
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@@ -299,42 -304,33 +304,48 @@@ ENTRY(startup_32_smp
  	movl %eax,%ss
  	leal -__PAGE_OFFSET(%ecx),%esp
  
+ #ifdef CONFIG_MICROCODE_EARLY
+ 	/* Early load ucode on AP. */
+ 	call load_ucode_ap
+ #endif
+ 
+ 
  default_entry:
 +#define CR0_STATE	(X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | \
 +			 X86_CR0_NE | X86_CR0_WP | X86_CR0_AM | \
 +			 X86_CR0_PG)
 +	movl $(CR0_STATE & ~X86_CR0_PG),%eax
 +	movl %eax,%cr0
 +
 +/*
 + * We want to start out with EFLAGS unambiguously cleared. Some BIOSes leave
 + * bits like NT set. This would confuse the debugger if this code is traced. So
 + * initialize them properly now before switching to protected mode. That means
 + * DF in particular (even though we have cleared it earlier after copying the
 + * command line) because GCC expects it.
 + */
 +	pushl $0
 +	popfl
 +
  /*
 - *	New page tables may be in 4Mbyte page mode and may
 - *	be using the global pages. 
 + * New page tables may be in 4Mbyte page mode and may be using the global pages.
   *
 - *	NOTE! If we are on a 486 we may have no cr4 at all!
 - *	Specifically, cr4 exists if and only if CPUID exists
 - *	and has flags other than the FPU flag set.
 + * NOTE! If we are on a 486 we may have no cr4 at all! Specifically, cr4 exists
 + * if and only if CPUID exists and has flags other than the FPU flag set.
   */
 +	movl $-1,pa(X86_CPUID)		# preset CPUID level
  	movl $X86_EFLAGS_ID,%ecx
  	pushl %ecx
 -	popfl
 -	pushfl
 -	popl %eax
 -	pushl $0
 -	popfl
 +	popfl				# set EFLAGS=ID
  	pushfl
 -	popl %edx
 -	xorl %edx,%eax
 -	testl %ecx,%eax
 -	jz 6f			# No ID flag = no CPUID = no CR4
 +	popl %eax			# get EFLAGS
 +	testl $X86_EFLAGS_ID,%eax	# did EFLAGS.ID remained set?
 +	jz enable_paging		# hw disallowed setting of ID bit
 +					# which means no CPUID and no CR4
 +
 +	xorl %eax,%eax
 +	cpuid
 +	movl %eax,pa(X86_CPUID)		# save largest std CPUID function
  
  	movl $1,%eax
  	cpuid