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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/boot/pmjump.S
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/boot/pmjump.S')
-rw-r--r--kernel/arch/x86/boot/pmjump.S77
1 files changed, 77 insertions, 0 deletions
diff --git a/kernel/arch/x86/boot/pmjump.S b/kernel/arch/x86/boot/pmjump.S
new file mode 100644
index 000000000..3e0edc6d2
--- /dev/null
+++ b/kernel/arch/x86/boot/pmjump.S
@@ -0,0 +1,77 @@
+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * The actual transition into protected mode
+ */
+
+#include <asm/boot.h>
+#include <asm/processor-flags.h>
+#include <asm/segment.h>
+#include <linux/linkage.h>
+
+ .text
+ .code16
+
+/*
+ * void protected_mode_jump(u32 entrypoint, u32 bootparams);
+ */
+GLOBAL(protected_mode_jump)
+ movl %edx, %esi # Pointer to boot_params table
+
+ xorl %ebx, %ebx
+ movw %cs, %bx
+ shll $4, %ebx
+ addl %ebx, 2f
+ jmp 1f # Short jump to serialize on 386/486
+1:
+
+ movw $__BOOT_DS, %cx
+ movw $__BOOT_TSS, %di
+
+ movl %cr0, %edx
+ orb $X86_CR0_PE, %dl # Protected mode
+ movl %edx, %cr0
+
+ # Transition to 32-bit mode
+ .byte 0x66, 0xea # ljmpl opcode
+2: .long in_pm32 # offset
+ .word __BOOT_CS # segment
+ENDPROC(protected_mode_jump)
+
+ .code32
+ .section ".text32","ax"
+GLOBAL(in_pm32)
+ # Set up data segments for flat 32-bit mode
+ movl %ecx, %ds
+ movl %ecx, %es
+ movl %ecx, %fs
+ movl %ecx, %gs
+ movl %ecx, %ss
+ # The 32-bit code sets up its own stack, but this way we do have
+ # a valid stack if some debugging hack wants to use it.
+ addl %ebx, %esp
+
+ # Set up TR to make Intel VT happy
+ ltr %di
+
+ # Clear registers to allow for future extensions to the
+ # 32-bit boot protocol
+ xorl %ecx, %ecx
+ xorl %edx, %edx
+ xorl %ebx, %ebx
+ xorl %ebp, %ebp
+ xorl %edi, %edi
+
+ # Set up LDTR to make Intel VT happy
+ lldt %cx
+
+ jmpl *%eax # Jump to the 32-bit entrypoint
+ENDPROC(in_pm32)