---

yaml
---
r: 53930
b: refs/heads/master
c: c7f81c9
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 484ad393659f20d784a3a93613fb3fd3d9f171fa
+refs/heads/master: c7f81c9453375d6416658995eafd3397cb9bba1d

trunk/arch/i386/Kconfig.cpu

@@ -240,14 +240,19 @@ config X86_L1_CACHE_SHIFT
 	default "5" if MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
 	default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MVIAC7
 
+config X86_XADD
+	bool
+	depends on !M386
+	default y
+
 config RWSEM_GENERIC_SPINLOCK
 	bool
-	depends on M386
+	depends on !X86_XADD
 	default y
 
 config RWSEM_XCHGADD_ALGORITHM
 	bool
-	depends on !M386
+	depends on X86_XADD
 	default y
 
 config ARCH_HAS_ILOG2_U32
@@ -331,3 +336,16 @@ config X86_TSC
 	bool
 	depends on (MWINCHIP3D || MWINCHIP2 || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2) && !X86_NUMAQ
 	default y
+
+# this should be set for all -march=.. options where the compiler
+# generates cmov.
+config X86_CMOV
+	bool
+	depends on (MK7 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7)
+	default y
+
+config X86_MINIMUM_CPU_MODEL
+	int
+	default "4" if X86_XADD || X86_CMPXCHG || X86_BSWAP
+	default "0"
+

trunk/arch/i386/boot/setup.S

@@ -302,7 +302,24 @@ good_sig:
 
 loader_panic_mess: .string "Wrong loader, giving up..."
 
+# check minimum cpuid
+# we do this here because it is the last place we can actually
+# show a user visible error message. Later the video modus
+# might be already messed up.
 loader_ok:
+	call verify_cpu
+	testl  %eax,%eax
+	jz	cpu_ok
+	lea	cpu_panic_mess,%si
+	call	prtstr
+1:	jmp	1b
+
+cpu_panic_mess:
+	.asciz  "PANIC: CPU too old for this kernel."
+
+#include "../kernel/verify_cpu.S"
+
+cpu_ok:
 # Get memory size (extended mem, kB)
 
 	xorl	%eax, %eax

trunk/arch/i386/kernel/verify_cpu.S

@@ -0,0 +1,65 @@
+/* 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

trunk/include/asm-i386/cpufeature.h

@@ -7,7 +7,10 @@
 #ifndef __ASM_I386_CPUFEATURE_H
 #define __ASM_I386_CPUFEATURE_H
 
+#ifndef __ASSEMBLY__
 #include <linux/bitops.h>
+#endif
+#include <asm/required-features.h>
 
 #define NCAPINTS	7	/* N 32-bit words worth of info */
 

trunk/include/asm-i386/required-features.h

@@ -0,0 +1,34 @@
+#ifndef _ASM_REQUIRED_FEATURES_H
+#define _ASM_REQUIRED_FEATURES_H 1
+
+/* Define minimum CPUID feature set for kernel These bits are checked
+   really early to actually display a visible error message before the
+   kernel dies.  Only add word 0 bits here
+
+   Some requirements that are not in CPUID yet are also in the
+   CONFIG_X86_MINIMUM_CPU mode which is checked too.
+
+   The real information is in arch/i386/Kconfig.cpu, this just converts
+   the CONFIGs into a bitmask */
+
+#ifdef CONFIG_X86_PAE
+#define NEED_PAE	(1<<X86_FEATURE_PAE)
+#else
+#define NEED_PAE	0
+#endif
+
+#ifdef CONFIG_X86_CMOV
+#define NEED_CMOV	(1<<X86_FEATURE_CMOV)
+#else
+#define NEED_CMOV	0
+#endif
+
+#ifdef CONFIG_X86_CMPXCHG64
+#define NEED_CMPXCHG64  (1<<X86_FEATURE_CX8)
+#else
+#define NEED_CMPXCHG64  0
+#endif
+
+#define REQUIRED_MASK1	(NEED_PAE|NEED_CMOV|NEED_CMPXCHG64)
+
+#endif