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>master
parent
ddf7355a73
commit
7d9cde1031
@ -0,0 +1,130 @@ |
|||||||
|
/*
|
||||||
|
* Tiny printf version for SPL |
||||||
|
* |
||||||
|
* Copied from: |
||||||
|
* http://www.sparetimelabs.com/printfrevisited/printfrevisited.php
|
||||||
|
* |
||||||
|
* Copyright (C) 2004,2008 Kustaa Nyholm |
||||||
|
* |
||||||
|
* SPDX-License-Identifier: LGPL-2.1+ |
||||||
|
*/ |
||||||
|
|
||||||
|
#include <common.h> |
||||||
|
#include <stdarg.h> |
||||||
|
#include <serial.h> |
||||||
|
|
||||||
|
static char *bf; |
||||||
|
static char buf[12]; |
||||||
|
static unsigned int num; |
||||||
|
static char uc; |
||||||
|
static char zs; |
||||||
|
|
||||||
|
static void out(char c) |
||||||
|
{ |
||||||
|
*bf++ = c; |
||||||
|
} |
||||||
|
|
||||||
|
static void out_dgt(char dgt) |
||||||
|
{ |
||||||
|
out(dgt + (dgt < 10 ? '0' : (uc ? 'A' : 'a') - 10)); |
||||||
|
zs = 1; |
||||||
|
} |
||||||
|
|
||||||
|
static void div_out(unsigned int div) |
||||||
|
{ |
||||||
|
unsigned char dgt = 0; |
||||||
|
|
||||||
|
num &= 0xffff; /* just for testing the code with 32 bit ints */ |
||||||
|
while (num >= div) { |
||||||
|
num -= div; |
||||||
|
dgt++; |
||||||
|
} |
||||||
|
|
||||||
|
if (zs || dgt > 0) |
||||||
|
out_dgt(dgt); |
||||||
|
} |
||||||
|
|
||||||
|
int printf(const char *fmt, ...) |
||||||
|
{ |
||||||
|
va_list va; |
||||||
|
char ch; |
||||||
|
char *p; |
||||||
|
|
||||||
|
va_start(va, fmt); |
||||||
|
|
||||||
|
while ((ch = *(fmt++))) { |
||||||
|
if (ch != '%') { |
||||||
|
putc(ch); |
||||||
|
} else { |
||||||
|
char lz = 0; |
||||||
|
char w = 0; |
||||||
|
|
||||||
|
ch = *(fmt++); |
||||||
|
if (ch == '0') { |
||||||
|
ch = *(fmt++); |
||||||
|
lz = 1; |
||||||
|
} |
||||||
|
|
||||||
|
if (ch >= '0' && ch <= '9') { |
||||||
|
w = 0; |
||||||
|
while (ch >= '0' && ch <= '9') { |
||||||
|
w = (((w << 2) + w) << 1) + ch - '0'; |
||||||
|
ch = *fmt++; |
||||||
|
} |
||||||
|
} |
||||||
|
bf = buf; |
||||||
|
p = bf; |
||||||
|
zs = 0; |
||||||
|
|
||||||
|
switch (ch) { |
||||||
|
case 0: |
||||||
|
goto abort; |
||||||
|
case 'u': |
||||||
|
case 'd': |
||||||
|
num = va_arg(va, unsigned int); |
||||||
|
if (ch == 'd' && (int)num < 0) { |
||||||
|
num = -(int)num; |
||||||
|
out('-'); |
||||||
|
} |
||||||
|
div_out(10000); |
||||||
|
div_out(1000); |
||||||
|
div_out(100); |
||||||
|
div_out(10); |
||||||
|
out_dgt(num); |
||||||
|
break; |
||||||
|
case 'x': |
||||||
|
case 'X': |
||||||
|
uc = ch == 'X'; |
||||||
|
num = va_arg(va, unsigned int); |
||||||
|
div_out(0x1000); |
||||||
|
div_out(0x100); |
||||||
|
div_out(0x10); |
||||||
|
out_dgt(num); |
||||||
|
break; |
||||||
|
case 'c': |
||||||
|
out((char)(va_arg(va, int))); |
||||||
|
break; |
||||||
|
case 's': |
||||||
|
p = va_arg(va, char*); |
||||||
|
break; |
||||||
|
case '%': |
||||||
|
out('%'); |
||||||
|
default: |
||||||
|
break; |
||||||
|
} |
||||||
|
|
||||||
|
*bf = 0; |
||||||
|
bf = p; |
||||||
|
while (*bf++ && w > 0) |
||||||
|
w--; |
||||||
|
while (w-- > 0) |
||||||
|
putc(lz ? '0' : ' '); |
||||||
|
while ((ch = *p++)) |
||||||
|
putc(ch); |
||||||
|
} |
||||||
|
} |
||||||
|
|
||||||
|
abort: |
||||||
|
va_end(va); |
||||||
|
return 0; |
||||||
|
} |
Loading…
Reference in new issue