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.
Thos 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.b...@aribaud.net>
---
This patch has been build-tested and run-tested on ED Mini V2,
above the "edmini: switch to SPL" patch, and found to reduce
U-Boot size by 25% and SPL size by 14%... and to run fine. :)
This patch has also been tested against side effects on the
non-Thumb wireless_space target. The binaries produced with
and without ths patch were found to differ only by their
version string.
Changes in v2:
- fixed a typo in the commit message
- added file arch/arm/thumb1/include/asm/proc-armv/system.h,
which overrides arch/arm/include/asm/proc-armv/system.h
when building for Thumb-1 and provides non-functional but
Thumb-compilable IRQ and FIQ related macros and functions.
Makefile | 2 +
arch/arm/Kconfig | 4 ++
arch/arm/cpu/arm926ejs/Makefile | 11 ++++
arch/arm/lib/Makefile | 11 ++++
arch/arm/mach-orion5x/Makefile | 10 ++++
arch/arm/thumb1/include/asm/proc-armv/system.h | 69 ++++++++++++++++++++++++++
examples/standalone/Makefile | 10 ++++
include/configs/edminiv2.h | 4 +-
8 files changed, 120 insertions(+), 1 deletion(-)
create mode 100644 arch/arm/thumb1/include/asm/proc-armv/system.h
diff --git a/Makefile b/Makefile
index bd4abab..7dc9dc6 100644
--- a/Makefile
+++ b/Makefile
@@ -593,6 +593,8 @@ KBUILD_CFLAGS += $(KCFLAGS)
UBOOTINCLUDE := \
-Iinclude \
$(if $(KBUILD_SRC), -I$(srctree)/include) \
+ $(if $(CONFIG_SYS_THUMB_BUILD), $(if $(CONFIG_HAS_THUMB2),, \
+ -I$(srctree)/arch/$(ARCH)/thumb1/include),) \
-I$(srctree)/arch/$(ARCH)/include \
-include $(srctree)/include/linux/kconfig.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 820ba1c..35420ca 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -10,6 +10,9 @@ config ARM64
config HAS_VBAR
bool
+config HAS_THUMB2
+ bool
+
config CPU_ARM720T
bool
@@ -32,6 +35,7 @@ config CPU_ARM1176
config CPU_V7
bool
select HAS_VBAR
+ select HAS_THUMB2
config CPU_PXA
bool
diff --git a/arch/arm/cpu/arm926ejs/Makefile b/arch/arm/cpu/arm926ejs/Makefile
index f5944cc..090d64b 100644
--- a/arch/arm/cpu/arm926ejs/Makefile
+++ b/arch/arm/cpu/arm926ejs/Makefile
@@ -22,3 +22,14 @@ obj-$(CONFIG_MX27) += mx27/
obj-$(if $(filter mxs,$(SOC)),y) += mxs/
obj-$(CONFIG_PANTHEON) += pantheon/
obj-$(if $(filter spear,$(SOC)),y) += spear/
+
+# some files can only build in ARM or THUMB2, not THUMB1
+
+ifdef CONFIG_SYS_THUMB_BUILD
+ifndef CONFIG_HAS_THUMB2
+
+CFLAGS_cpu.o := -marm
+CFLAGS_cache.o := -marm
+
+endif
+endif
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index da8ed72..a753bca 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -55,3 +55,14 @@ obj-$(CONFIG_DEBUG_LL) += debug.o
ifneq (,$(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
+
+CFLAGS_cache.o := -marm
+CFLAGS_cache-cp15.o := -marm
+
+endif
+endif
diff --git a/arch/arm/mach-orion5x/Makefile b/arch/arm/mach-orion5x/Makefile
index 546ebcb..33dcad4 100644
--- a/arch/arm/mach-orion5x/Makefile
+++ b/arch/arm/mach-orion5x/Makefile
@@ -16,3 +16,13 @@ obj-y += timer.o
ifndef CONFIG_SKIP_LOWLEVEL_INIT
obj-y += lowlevel_init.o
endif
+
+# some files can only build in ARM or THUMB2, not THUMB1
+
+ifdef CONFIG_SYS_THUMB_BUILD
+ifndef CONFIG_HAS_THUMB2
+
+CFLAGS_cpu.o := -marm
+
+endif
+endif
diff --git a/arch/arm/thumb1/include/asm/proc-armv/system.h
b/arch/arm/thumb1/include/asm/proc-armv/system.h
new file mode 100644
index 0000000..7dfbf3d
--- /dev/null
+++ b/arch/arm/thumb1/include/asm/proc-armv/system.h
@@ -0,0 +1,69 @@
+/*
+ * Thumb-1 drop-in for the linux/include/asm-arm/proc-armv/system.h
+ *
+ * (C) Copyright 2015
+ * Albert ARIBAUD <albert.u.b...@aribaud.net>
+ *
+ * The original file does not build in Thumb mode. However, in U-Boot
+ * we don't use interrupt context, so we can redefine these as empty
+ * memory barriers, which makes Thumb-1 compiler happy.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/*
+ * Use the same macro name as linux/include/asm-arm/proc-armv/system.h
+ * here, so that if the original ever gets included after us, it won't
+ * try to re-redefine anything.
+ */
+
+#ifndef __ASM_PROC_SYSTEM_H
+#define __ASM_PROC_SYSTEM_H
+
+/*
+ * Redefine all original macros with static inline functions containing
+ * a simple memory barrier, so that they produce the same instruction
+ * ordering constraints as their original counterparts.
+ * We use static inline functions rather than macros so that we can tell
+ * the compiler to not complain about unused arguments.
+ */
+
+static inline void local_irq_save(
+ unsigned long flags __attribute__((unused)))
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void local_irq_enable(void)
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void local_irq_disable(void)
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void __stf(void)
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void __clf(void)
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void local_save_flags(
+ unsigned long flags __attribute__((unused)))
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+static inline void local_irq_restore(
+ unsigned long flags __attribute__((unused)))
+{
+ __asm__ __volatile__ ("" : : : "memory");
+}
+
+#endif /* __ASM_PROC_SYSTEM_H */
diff --git a/examples/standalone/Makefile b/examples/standalone/Makefile
index 0863a8c..5a6ae00 100644
--- a/examples/standalone/Makefile
+++ b/examples/standalone/Makefile
@@ -73,3 +73,13 @@ $(obj)/%.srec: $(obj)/% FORCE
$(obj)/%.bin: OBJCOPYFLAGS := -O binary
$(obj)/%.bin: $(obj)/% FORCE
$(call if_changed,objcopy)
+
+# some files can only build in ARM or THUMB2, not THUMB1
+
+ifdef CONFIG_SYS_THUMB_BUILD
+ifndef CONFIG_HAS_THUMB2
+
+CFLAGS_stubs.o := -marm
+
+endif
+endif
diff --git a/include/configs/edminiv2.h b/include/configs/edminiv2.h
index 70a698a..112583b 100644
--- a/include/configs/edminiv2.h
+++ b/include/configs/edminiv2.h
@@ -12,6 +12,8 @@
#ifndef _CONFIG_EDMINIV2_H
#define _CONFIG_EDMINIV2_H
+#define CONFIG_SYS_THUMB_BUILD
+
/*
* Version number information
*/
@@ -203,7 +205,7 @@
/*
* Size of malloc() pool
*/
-#define CONFIG_SYS_MALLOC_LEN (1024 * 256) /* 256kB for malloc() */
+#define CONFIG_SYS_MALLOC_LEN (1024 * 1024) /* 1MB for malloc() */
/*
* Other required minimal configurations
--
2.1.0
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