lib/tiny-printf.c: Add tiny printf function for space limited environments
This patch adds a small printf() version that supports all basic formats.
Its intented to be used in U-Boot SPL versions on platforms with very
limited internal RAM sizes.
To enable it, just define CONFIG_USE_TINY_PRINTF in your defconfig. This
will result in the SPL using this tiny function and the main U-Boot
still using the full-blown printf() function.
This code was copied from:
http://www.sparetimelabs.com/printfrevisited
With mostly only coding style related changes so that its checkpatch
clean.
The size reduction is about 2.5KiB. Here a comparison for the db-mv784mp-gp
(Marvell AXP) SPL:
Without this patch:
58963 18536 1928 79427 13643 ./spl/u-boot-spl
With this patch:
56542 18536 1956 77034 12cea ./spl/u-boot-spl
Note:
To make it possible to compile tiny-printf.c instead of vsprintf.c when
CONFIG_USE_TINY_PRINTF is defined, the functions printf() and vprintf() are
moved from common/console.c into vsprintf.c in this patch.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Tom Rini <trini@konsulko.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
diff --git a/lib/Kconfig b/lib/Kconfig
index 30e84ed..9d580e4 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -36,6 +36,16 @@
Thumb-2, about 420 bytes). Enable this option for safety when
using sprintf() with data you do not control.
+config USE_TINY_PRINTF
+ bool "Enable tiny printf() version"
+ help
+ This option enables a tiny, stripped down printf version.
+ This should only be used in space limited environments,
+ like SPL versions with hard memory limits. This version
+ reduces the code size by about 2.5KiB on armv7.
+
+ The supported format specifiers are %c, %s, %u/%d and %x.
+
config REGEX
bool "Enable regular expression support"
default y if NET