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authorGraeme Russ <graeme.russ@gmail.com>2010-04-24 00:05:49 +1000
committerWolfgang Denk <wd@denx.de>2010-05-06 00:17:01 +0200
commit95ffaba39042064c5eb68404894fd6b0f1d6a3e3 (patch)
tree6a0a1572913552b1f6a94987a341677c00dbfc36 /include/linux/compiler-gcc.h
parent79ea6b87011c0524ced31359e2be7aac97c29d0a (diff)
downloadtalos-obmc-uboot-95ffaba39042064c5eb68404894fd6b0f1d6a3e3.tar.gz
talos-obmc-uboot-95ffaba39042064c5eb68404894fd6b0f1d6a3e3.zip
x86: Fix support for booting bzImage
Add support for newer (up to 2.6.33) kernels Add zboot command which takes the address of a bzImage as its first argument and (optionally) the size of the bzImage as the second argument (the second argument is needed for older kernels which do not include the bzImage size in the header) Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Diffstat (limited to 'include/linux/compiler-gcc.h')
-rw-r--r--include/linux/compiler-gcc.h87
1 files changed, 87 insertions, 0 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
new file mode 100644
index 0000000000..73dcf804bc
--- /dev/null
+++ b/include/linux/compiler-gcc.h
@@ -0,0 +1,87 @@
+#ifndef __LINUX_COMPILER_H
+#error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead."
+#endif
+
+/*
+ * Common definitions for all gcc versions go here.
+ */
+
+
+/* Optimization barrier */
+/* The "volatile" is due to gcc bugs */
+#define barrier() __asm__ __volatile__("": : :"memory")
+
+/*
+ * This macro obfuscates arithmetic on a variable address so that gcc
+ * shouldn't recognize the original var, and make assumptions about it.
+ *
+ * This is needed because the C standard makes it undefined to do
+ * pointer arithmetic on "objects" outside their boundaries and the
+ * gcc optimizers assume this is the case. In particular they
+ * assume such arithmetic does not wrap.
+ *
+ * A miscompilation has been observed because of this on PPC.
+ * To work around it we hide the relationship of the pointer and the object
+ * using this macro.
+ *
+ * Versions of the ppc64 compiler before 4.1 had a bug where use of
+ * RELOC_HIDE could trash r30. The bug can be worked around by changing
+ * the inline assembly constraint from =g to =r, in this particular
+ * case either is valid.
+ */
+#define RELOC_HIDE(ptr, off) \
+ ({ unsigned long __ptr; \
+ __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \
+ (typeof(ptr)) (__ptr + (off)); })
+
+/* &a[0] degrades to a pointer: a different type from an array */
+#define __must_be_array(a) \
+ BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0])))
+
+/*
+ * Force always-inline if the user requests it so via the .config,
+ * or if gcc is too old:
+ */
+#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \
+ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4)
+# define inline inline __attribute__((always_inline))
+# define __inline__ __inline__ __attribute__((always_inline))
+# define __inline __inline __attribute__((always_inline))
+#endif
+
+#define __deprecated __attribute__((deprecated))
+#define __packed __attribute__((packed))
+#define __weak __attribute__((weak))
+
+/*
+ * it doesn't make sense on ARM (currently the only user of __naked) to trace
+ * naked functions because then mcount is called without stack and frame pointer
+ * being set up and there is no chance to restore the lr register to the value
+ * before mcount was called.
+ */
+#define __naked __attribute__((naked)) notrace
+
+#define __noreturn __attribute__((noreturn))
+
+/*
+ * From the GCC manual:
+ *
+ * Many functions have no effects except the return value and their
+ * return value depends only on the parameters and/or global
+ * variables. Such a function can be subject to common subexpression
+ * elimination and loop optimization just as an arithmetic operator
+ * would be.
+ * [...]
+ */
+#define __pure __attribute__((pure))
+#define __aligned(x) __attribute__((aligned(x)))
+#define __printf(a,b) __attribute__((format(printf,a,b)))
+#define noinline __attribute__((noinline))
+#define __attribute_const__ __attribute__((__const__))
+#define __maybe_unused __attribute__((unused))
+#define __always_unused __attribute__((unused))
+
+#define __gcc_header(x) #x
+#define _gcc_header(x) __gcc_header(linux/compiler-gcc##x.h)
+#define gcc_header(x) _gcc_header(x)
+#include gcc_header(__GNUC__)
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