arm: support Thumb-1 with CONFIG_SYS_THUMB_BUILD
When building a Thumb-1-only target with CONFIG_SYS_THUMB_BUILD,
some files fail to build, most of the time because they include
mcr instructions, which only exist for Thumb-2.
This patch introduces a Kconfig option CONFIG_THUMB2 and uses
it to select between Thumb-2 and ARM mode for the aforementioned
files.
Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 2bdfaba..f3db7b5 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -60,3 +60,27 @@
ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
extra-y += eabi_compat.o
endif
+
+# some files can only build in ARM or THUMB2, not THUMB1
+
+ifdef CONFIG_SYS_THUMB_BUILD
+ifndef CONFIG_HAS_THUMB2
+
+# for C files, just apend -marm, which will override previous -mthumb*
+
+CFLAGS_cache.o := -marm
+CFLAGS_cache-cp15.o := -marm
+
+# For .S, drop -mthumb* and other thumb-related options.
+# CFLAGS_REMOVE_* would not have an effet, so AFLAGS_REMOVE_*
+# was implemented and is used here.
+# Also, define ${target}_NO_THUMB_BUILD for these two targets
+# so that the code knows it should not use Thumb.
+
+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
diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c
index cd13db3..3bd8710 100644
--- a/arch/arm/lib/cache.c
+++ b/arch/arm/lib/cache.c
@@ -88,3 +88,14 @@
return next;
}
#endif /* CONFIG_SYS_NONCACHED_MEMORY */
+
+#if defined(CONFIG_SYS_THUMB_BUILD)
+void invalidate_l2_cache(void)
+{
+ unsigned int val = 0;
+
+ asm volatile("mcr p15, 1, %0, c15, c11, 0 @ invl l2 cache"
+ : : "r" (val) : "cc");
+ isb();
+}
+#endif
diff --git a/arch/arm/lib/memcpy.S b/arch/arm/lib/memcpy.S
index eeaf003..7d9fc0f 100644
--- a/arch/arm/lib/memcpy.S
+++ b/arch/arm/lib/memcpy.S
@@ -13,7 +13,7 @@
#include <linux/linkage.h>
#include <asm/assembler.h>
-#ifdef CONFIG_SYS_THUMB_BUILD
+#if defined(CONFIG_SYS_THUMB_BUILD) && !defined(MEMCPY_NO_THUMB_BUILD)
#define W(instr) instr.w
#else
#define W(instr) instr
@@ -62,7 +62,7 @@
/* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
.syntax unified
-#ifdef CONFIG_SYS_THUMB_BUILD
+#if defined(CONFIG_SYS_THUMB_BUILD) && !defined(MEMCPY_NO_THUMB_BUILD)
.thumb
.thumb_func
#endif
diff --git a/arch/arm/lib/memset.S b/arch/arm/lib/memset.S
index 7208f20..df053a3 100644
--- a/arch/arm/lib/memset.S
+++ b/arch/arm/lib/memset.S
@@ -16,7 +16,7 @@
.align 5
.syntax unified
-#ifdef CONFIG_SYS_THUMB_BUILD
+#if defined(CONFIG_SYS_THUMB_BUILD) && !defined(MEMSET_NO_THUMB_BUILD)
.thumb
.thumb_func
#endif