diff --git a/log/tfm_log_raw.c b/log/tfm_log_raw.c
new file mode 100644
index 0000000..86cf1c3
--- /dev/null
+++ b/log/tfm_log_raw.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2019-2020, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
+#include "uart_stdout.h"
+
+#define PRINT_BUFF_SIZE 32
+#define NUM_BUFF_SIZE 12
+
+struct formatted_buffer_t {
+    size_t pos;
+    uint8_t buf[PRINT_BUFF_SIZE];
+};
+
+const char hex_digits_lo[] = {'0', '1', '2', '3', '4', '5', '6', '7',
+                              '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
+const char hex_digits_up[] = {'0', '1', '2', '3', '4', '5', '6', '7',
+                              '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
+
+static void _tfm_flush_formatted_buffer(struct formatted_buffer_t *pb,
+                                        uint8_t data)
+{
+    pb->buf[pb->pos++] = data;
+    if (pb->pos >= PRINT_BUFF_SIZE) {
+        pb->pos = 0;
+        /* uart flush and print here. */
+        stdio_output_string(pb->buf, PRINT_BUFF_SIZE);
+    }
+}
+
+static int _tfm_string_output(struct formatted_buffer_t *pb,
+                              const char *str)
+{
+    int count = 0;
+
+    while (*str) {
+        _tfm_flush_formatted_buffer(pb, *str++);
+        count++;
+    }
+
+    return count;
+}
+
+static int _tfm_dec_num_output(struct formatted_buffer_t *pb,
+                               int32_t num, uint8_t sign)
+{
+    int count = 0;
+    uint8_t num_buff[NUM_BUFF_SIZE] = {0};
+    uint32_t number = (uint32_t)num;
+    uint32_t k = 0;
+
+    if (sign == 'd' && num < 0) {
+        _tfm_flush_formatted_buffer(pb, '-');
+        count++;
+        number = -num;
+    }
+
+    do {
+        num_buff[k++] = '0' + number % 10;
+        number /= 10;
+    } while (number);
+
+    while (k) {
+        _tfm_flush_formatted_buffer(pb, num_buff[--k]);
+        count++;
+    }
+
+    return count;
+}
+
+static int _tfm_hex_num_output(struct formatted_buffer_t *pb, uint32_t num,
+                               const char *hex_digits)
+{
+    int count = 0;
+    uint8_t num_buff[NUM_BUFF_SIZE] = {0};
+    uint32_t k = 0;
+
+    do {
+        num_buff[k++] = hex_digits[num & 0x0f];
+        num >>= 4;
+    } while (num);
+
+    while (k) {
+        _tfm_flush_formatted_buffer(pb, num_buff[--k]);
+        count++;
+    }
+
+    return count;
+}
+
+static int _tfm_log_vprintf(const char *fmt, va_list ap)
+{
+    int count = 0;
+    struct formatted_buffer_t outputbuf;
+
+    outputbuf.pos = 0;
+
+    while (*fmt) {
+        if (*fmt == '%') {
+            switch (*(++fmt)) {
+            case 'd':
+            case 'i':
+                count += _tfm_dec_num_output(&outputbuf,
+                                             va_arg(ap, int32_t), 'd');
+                break;
+            case 'u':
+                count += _tfm_dec_num_output(&outputbuf,
+                                             va_arg(ap, int32_t), 'u');
+                break;
+            case 'x':
+                count += _tfm_hex_num_output(&outputbuf, va_arg(ap, uint32_t),
+                                             hex_digits_lo);
+                break;
+            case 'X':
+                count += _tfm_hex_num_output(&outputbuf, va_arg(ap, uint32_t),
+                                             hex_digits_up);
+                break;
+            case 'p':
+                count += _tfm_string_output(&outputbuf, "0x");
+                count += _tfm_hex_num_output(&outputbuf, va_arg(ap, uint32_t),
+                                             hex_digits_lo);
+                break;
+            case 's':
+                count += _tfm_string_output(&outputbuf, va_arg(ap, char*));
+                break;
+            case 'c':
+                _tfm_flush_formatted_buffer(&outputbuf,
+                                            (uint8_t)va_arg(ap, int32_t));
+                count++;
+                break;
+            case '%':
+                _tfm_flush_formatted_buffer(&outputbuf, '%');
+                count++;
+                break;
+            default:
+                count += _tfm_string_output(&outputbuf, "[Unsupported Tag]");
+                continue;
+            }
+            fmt++;
+        } else {
+            _tfm_flush_formatted_buffer(&outputbuf, *fmt++);
+            count++;
+        }
+    }
+
+    /* End of printf, flush buf */
+    if (outputbuf.pos) {
+        count += stdio_output_string(outputbuf.buf, outputbuf.pos);
+    }
+
+    return count;
+}
+
+int tfm_log_printf(const char *fmt, ...)
+{
+    int count = 0;
+    va_list ap;
+
+    va_start(ap, fmt);
+    count = _tfm_log_vprintf(fmt, ap);
+    va_end(ap);
+
+    return count;
+}