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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/include/asm/bios_ebda.h
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/include/asm/bios_ebda.h')
-rw-r--r--kernel/arch/x86/include/asm/bios_ebda.h60
1 files changed, 60 insertions, 0 deletions
diff --git a/kernel/arch/x86/include/asm/bios_ebda.h b/kernel/arch/x86/include/asm/bios_ebda.h
new file mode 100644
index 000000000..aa6a3170a
--- /dev/null
+++ b/kernel/arch/x86/include/asm/bios_ebda.h
@@ -0,0 +1,60 @@
+#ifndef _ASM_X86_BIOS_EBDA_H
+#define _ASM_X86_BIOS_EBDA_H
+
+#include <asm/io.h>
+
+/*
+ * Returns physical address of EBDA. Returns 0 if there is no EBDA.
+ */
+static inline unsigned int get_bios_ebda(void)
+{
+ /*
+ * There is a real-mode segmented pointer pointing to the
+ * 4K EBDA area at 0x40E.
+ */
+ unsigned int address = *(unsigned short *)phys_to_virt(0x40E);
+ address <<= 4;
+ return address; /* 0 means none */
+}
+
+/*
+ * Return the sanitized length of the EBDA in bytes, if it exists.
+ */
+static inline unsigned int get_bios_ebda_length(void)
+{
+ unsigned int address;
+ unsigned int length;
+
+ address = get_bios_ebda();
+ if (!address)
+ return 0;
+
+ /* EBDA length is byte 0 of the EBDA (stored in KiB) */
+ length = *(unsigned char *)phys_to_virt(address);
+ length <<= 10;
+
+ /* Trim the length if it extends beyond 640KiB */
+ length = min_t(unsigned int, (640 * 1024) - address, length);
+ return length;
+}
+
+void reserve_ebda_region(void);
+
+#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
+/*
+ * This is obviously not a great place for this, but we want to be
+ * able to scatter it around anywhere in the kernel.
+ */
+void check_for_bios_corruption(void);
+void start_periodic_check_for_corruption(void);
+#else
+static inline void check_for_bios_corruption(void)
+{
+}
+
+static inline void start_periodic_check_for_corruption(void)
+{
+}
+#endif
+
+#endif /* _ASM_X86_BIOS_EBDA_H */