Implement a leaner printf for Trusted Firmware
This patch implements a "tf_printf" which supports only the commonly
used format specifiers in Trusted Firmware, which uses a lot less
stack space than the stdlib printf function.
Fixes ARM-software/tf-issues#116
Change-Id: I7dfa1944f4c1e634b3e2d571f49afe02d109a351
diff --git a/common/bl_common.c b/common/bl_common.c
index d4bde51..60b63f1 100644
--- a/common/bl_common.c
+++ b/common/bl_common.c
@@ -148,12 +148,12 @@
const meminfo_t *mem_layout)
{
#if DEBUG
- printf("Trying to load image at address 0x%lx, size = 0x%lx\r\n",
+ tf_printf("Trying to load image at address 0x%lx, size = 0x%lx\r\n",
image_load_addr, image_size);
- printf("Current memory layout:\r\n");
- printf(" total region = [0x%lx, 0x%lx]\r\n", mem_layout->total_base,
+ tf_printf("Current memory layout:\r\n");
+ tf_printf(" total region = [0x%lx, 0x%lx]\r\n", mem_layout->total_base,
mem_layout->total_base + mem_layout->total_size);
- printf(" free region = [0x%lx, 0x%lx]\r\n", mem_layout->free_base,
+ tf_printf(" free region = [0x%lx, 0x%lx]\r\n", mem_layout->free_base,
mem_layout->free_base + mem_layout->free_size);
#endif
}
diff --git a/common/debug.c b/common/debug.c
index 0f59ed5..be54f5d 100644
--- a/common/debug.c
+++ b/common/debug.c
@@ -29,6 +29,7 @@
*/
#include <console.h>
#include <debug.h>
+#include <stdarg.h>
#include <stdio.h>
/******************************************************************
@@ -73,7 +74,7 @@
#if DEBUG
void __dead2 do_panic(const char *file, int line)
{
- printf("PANIC in file: %s line: %d\n", file, line);
+ tf_printf("PANIC in file: %s line: %d\n", file, line);
while (1)
;
}
@@ -87,7 +88,7 @@
/* x30 reports the next eligible instruction whereas we want the
* place where panic() is invoked. Hence decrement by 4.
*/
- printf("PANIC in PC location 0x%016X\n", pc_reg - 0x4);
+ tf_printf("PANIC in PC location 0x%016X\n", pc_reg - 0x4);
while (1)
;
diff --git a/common/tf_printf.c b/common/tf_printf.c
new file mode 100644
index 0000000..02461c0
--- /dev/null
+++ b/common/tf_printf.c
@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <debug.h>
+#include <stdarg.h>
+#include <stdint.h>
+
+/***********************************************************
+ * The tf_printf implementation for all BL stages
+ ***********************************************************/
+static void unsigned_num_print(unsigned long int unum, unsigned int radix)
+{
+ /* Just need enough space to store 64 bit decimal integer */
+ unsigned char num_buf[20];
+ int i = 0 , rem;
+
+ do {
+ rem = unum % radix;
+ if (rem < 0xa)
+ num_buf[i++] = '0' + rem;
+ else
+ num_buf[i++] = 'a' + (rem - 0xa);
+ } while (unum /= radix);
+
+ while (--i >= 0)
+ putchar(num_buf[i]);
+}
+
+static void string_print(const char *str)
+{
+ while (*str)
+ putchar(*str++);
+}
+
+/*******************************************************************
+ * Reduced format print for Trusted firmware.
+ * The following formats are supported by this print
+ * %x - 32 bit hexadecimal format
+ * %llx and %lx -64 bit hexadecimal format
+ * %s - string format
+ * %d or %i - signed 32 bit decimal format
+ * %u - unsigned 32 bit decimal format
+ * %ld and %lld - signed 64 bit decimal format
+ * %lu and %llu - unsigned 64 bit decimal format
+ * Exits on all other formats.
+ *******************************************************************/
+
+void tf_printf(const char *fmt, ...)
+{
+ va_list args;
+ int bit64;
+ int64_t num;
+ uint64_t unum;
+ char *str;
+
+ va_start(args, fmt);
+ while (*fmt) {
+ bit64 = 0;
+
+ if (*fmt == '%') {
+ fmt++;
+ /* Check the format specifier */
+loop:
+ switch (*fmt) {
+ case 'i': /* Fall through to next one */
+ case 'd':
+ if (bit64)
+ num = va_arg(args, int64_t);
+ else
+ num = va_arg(args, int32_t);
+
+ if (num < 0) {
+ putchar('-');
+ unum = (unsigned long int)-num;
+ } else
+ unum = (unsigned long int)num;
+
+ unsigned_num_print(unum, 10);
+ break;
+ case 's':
+ str = va_arg(args, char *);
+ string_print(str);
+ break;
+ case 'x':
+ if (bit64)
+ unum = va_arg(args, uint64_t);
+ else
+ unum = va_arg(args, uint32_t);
+
+ unsigned_num_print(unum, 16);
+ break;
+ case 'l':
+ bit64 = 1;
+ fmt++;
+ goto loop;
+ case 'u':
+ if (bit64)
+ unum = va_arg(args, uint64_t);
+ else
+ unum = va_arg(args, uint32_t);
+
+ unsigned_num_print(unum, 10);
+ break;
+ default:
+ /* Exit on any other format specifier */
+ goto exit;
+ }
+ fmt++;
+ continue;
+ }
+ putchar(*fmt++);
+ }
+exit:
+ va_end(args);
+}