Thumb-2: Add macros for the unified assembler syntax

This patch adds various C and assembler macros that help with using
the unified assembler syntax for compiling files to either ARM or
Thumb-2 modes.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

3 files changed, 130 insertions, 1 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index aef63c8e3d2d..da28e7ba6083 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -983,6 +983,9 @@ config HZ
         default AT91_TIMER_HZ if ARCH_AT91
         default 100
 
+config ARM_ASM_UNIFIED
+        bool
+
 config AEABI
         bool "Use the ARM EABI to compile the kernel"
         help
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index c877d6df23d1..3505572a21e6 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -95,7 +95,7 @@ endif
 
 # Need -Uarm for gcc < 3.x
 KBUILD_CFLAGS   +=$(CFLAGS_ABI) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm
-KBUILD_AFLAGS   +=$(CFLAGS_ABI) $(arch-y) $(tune-y) -msoft-float
+KBUILD_AFLAGS   +=$(CFLAGS_ABI) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float
 
 CHECKFLAGS      += -D__arm__
 
diff --git a/arch/arm/include/asm/unified.h b/arch/arm/include/asm/unified.h
new file mode 100644
index 000000000000..073e85b9b961
--- /dev/null
+++ b/arch/arm/include/asm/unified.h
@@ -0,0 +1,126 @@
+/*
+ * include/asm-arm/unified.h - Unified Assembler Syntax helper macros
+ *
+ * Copyright (C) 2008 ARM Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef __ASM_UNIFIED_H
+#define __ASM_UNIFIED_H
+
+#if defined(__ASSEMBLY__) && defined(CONFIG_ARM_ASM_UNIFIED)
+        .syntax unified
+#endif
+
+#ifdef CONFIG_THUMB2_KERNEL
+
+#if __GNUC__ < 4
+#error Thumb-2 kernel requires gcc >= 4
+#endif
+
+/* The CPSR bit describing the instruction set (Thumb) */
+#define PSR_ISETSTATE   PSR_T_BIT
+
+#define ARM(x...)
+#define THUMB(x...)     x
+#define W(instr)        instr.w
+#define BSYM(sym)       sym + 1
+
+#else   /* !CONFIG_THUMB2_KERNEL */
+
+/* The CPSR bit describing the instruction set (ARM) */
+#define PSR_ISETSTATE   0
+
+#define ARM(x...)       x
+#define THUMB(x...)
+#define W(instr)        instr
+#define BSYM(sym)       sym
+
+#endif  /* CONFIG_THUMB2_KERNEL */
+
+#ifndef CONFIG_ARM_ASM_UNIFIED
+
+/*
+ * If the unified assembly syntax isn't used (in ARM mode), these
+ * macros expand to an empty string
+ */
+#ifdef __ASSEMBLY__
+        .macro  it, cond
+        .endm
+        .macro  itt, cond
+        .endm
+        .macro  ite, cond
+        .endm
+        .macro  ittt, cond
+        .endm
+        .macro  itte, cond
+        .endm
+        .macro  itet, cond
+        .endm
+        .macro  itee, cond
+        .endm
+        .macro  itttt, cond
+        .endm
+        .macro  ittte, cond
+        .endm
+        .macro  ittet, cond
+        .endm
+        .macro  ittee, cond
+        .endm
+        .macro  itett, cond
+        .endm
+        .macro  itete, cond
+        .endm
+        .macro  iteet, cond
+        .endm
+        .macro  iteee, cond
+        .endm
+#else   /* !__ASSEMBLY__ */
+__asm__(
+"       .macro  it, cond\n"
+"       .endm\n"
+"       .macro  itt, cond\n"
+"       .endm\n"
+"       .macro  ite, cond\n"
+"       .endm\n"
+"       .macro  ittt, cond\n"
+"       .endm\n"
+"       .macro  itte, cond\n"
+"       .endm\n"
+"       .macro  itet, cond\n"
+"       .endm\n"
+"       .macro  itee, cond\n"
+"       .endm\n"
+"       .macro  itttt, cond\n"
+"       .endm\n"
+"       .macro  ittte, cond\n"
+"       .endm\n"
+"       .macro  ittet, cond\n"
+"       .endm\n"
+"       .macro  ittee, cond\n"
+"       .endm\n"
+"       .macro  itett, cond\n"
+"       .endm\n"
+"       .macro  itete, cond\n"
+"       .endm\n"
+"       .macro  iteet, cond\n"
+"       .endm\n"
+"       .macro  iteee, cond\n"
+"       .endm\n");
+#endif  /* __ASSEMBLY__ */
+
+#endif  /* CONFIG_ARM_ASM_UNIFIED */
+
+#endif  /* !__ASM_UNIFIED_H */