arm: include: Import unified.h from Linux kernel

Import unified.h from Linux kernel 4.4.6 , commit
0d1912303e54ed1b2a371be0bba51c384dd57326 . This header file contains
macros used in libgcc functions in Linux kernel on ARM and will be
needed for the libgcc sync.

Since unified.h defines the W(instr) macro, we must drop this from
the macro from memcpy.S , otherwise this triggers a warning about
symbol redefinition. In order to keep the changes to unified.h to
the minimum, tweak arch/arm/lib/Makefile such that it defines the
CONFIG_ARM_ASM_UNIFIED macro, which places .syntax unified into all
of the assembler files. This is mandatory.

Moreover, for Thumb2 build, define CONFIG_THUMB2_KERNEL macro if and
only if Thumb2 build is enabled. This macro is checked by unified.h
and toggles between ARM and Thumb2 variant of the instructions in the
assembler source files.

Finally, this patch defines __LINUX_ARM_ARCH__=N macro based on the
new CONFIG_SYS_ARM_ARCH Kconfig option. This macro selects between
more optimal and more dense codepaths which work on armv5 and newer
and less optimal codepaths which work on armv4 and possible armv3m.
Tegra2 needs the same special handling as it does in arch/arm/Makefile
to cater for the arm720t boot core.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

arch/arm/include/asm/assembler.h

@@ -15,6 +15,7 @@
  */
 
 #include <config.h>
+#include <asm/unified.h>
 
 /*
  * Endian independent macros for shifting bytes within registers.

arch/arm/include/asm/unified.h

@@ -0,0 +1,129 @@
+/*
+ * include/asm-arm/unified.h - Unified Assembler Syntax helper macros
+ *
+ * Copyright (C) 2008 ARM Limited
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#ifndef __ASM_UNIFIED_H
+#define __ASM_UNIFIED_H
+
+#if defined(__ASSEMBLY__) && defined(CONFIG_ARM_ASM_UNIFIED)
+	.syntax unified
+#endif
+
+#ifdef CONFIG_CPU_V7M
+#define AR_CLASS(x...)
+#define M_CLASS(x...)	x
+#else
+#define AR_CLASS(x...)	x
+#define M_CLASS(x...)
+#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
+#ifdef __ASSEMBLY__
+#define W(instr)	instr.w
+#else
+#define WASM(instr)	#instr ".w"
+#endif
+
+#else	/* !CONFIG_THUMB2_KERNEL */
+
+/* The CPSR bit describing the instruction set (ARM) */
+#define PSR_ISETSTATE	0
+
+#define ARM(x...)	x
+#define THUMB(x...)
+#ifdef __ASSEMBLY__
+#define W(instr)	instr
+#else
+#define WASM(instr)	#instr
+#endif
+
+#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 */

arch/arm/lib/Makefile

@@ -62,9 +62,17 @@ ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
 extra-y	+= eabi_compat.o
 endif
 
+asflags-y += -DCONFIG_ARM_ASM_UNIFIED
+ifeq ($(CONFIG_SPL_BUILD)$(CONFIG_TEGRA),yy)
+asflags-y += -D__LINUX_ARM_ARCH__=4
+else
+asflags-y += -D__LINUX_ARM_ARCH__=$(CONFIG_SYS_ARM_ARCH)
+endif
+
 # some files can only build in ARM or THUMB2, not THUMB1
 
 ifdef CONFIG_SYS_THUMB_BUILD
+asflags-$(CONFIG_HAS_THUMB2) += -DCONFIG_THUMB2_KERNEL
 ifndef CONFIG_HAS_THUMB2
 
 # for C files, just apend -marm, which will override previous -mthumb*
@@ -82,6 +90,5 @@ AFLAGS_REMOVE_memset.o := -mthumb -mthumb-interwork
 AFLAGS_REMOVE_memcpy.o := -mthumb -mthumb-interwork
 AFLAGS_memset.o := -DMEMSET_NO_THUMB_BUILD
 AFLAGS_memcpy.o := -DMEMCPY_NO_THUMB_BUILD
-
 endif
 endif

arch/arm/lib/memcpy.S

@@ -13,12 +13,6 @@
 #include <linux/linkage.h>
 #include <asm/assembler.h>
 
-#if defined(CONFIG_SYS_THUMB_BUILD) && !defined(MEMCPY_NO_THUMB_BUILD)
-#define W(instr)	instr.w
-#else
-#define W(instr)	instr
-#endif
-
 #define LDR1W_SHIFT	0
 #define STR1W_SHIFT	0