Core: Remove 'tfm_bitcount' referencing

Replace all 'tfm_bitcount' calling with 'tfm_is_one_bit_set'.

Change-Id: I6d7bc3d85f3cc31c7d0564a3f5104e4d60dc6597
Signed-off-by: Ken Liu <ken.liu@arm.com>
diff --git a/secure_fw/core/include/secure_utilities.h b/secure_fw/core/include/secure_utilities.h
index 98a191f..83dc402 100644
--- a/secure_fw/core/include/secure_utilities.h
+++ b/secure_fw/core/include/secure_utilities.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019, Arm Limited. All rights reserved.
+ * Copyright (c) 2017-2020, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
@@ -19,8 +19,6 @@
 
 #define ERROR_MSG(msg)
 
-int32_t tfm_bitcount(uint32_t n);
-
 bool tfm_is_one_bit_set(uint32_t n);
 
 #endif /* __SECURE_UTILITIES_H__ */
diff --git a/secure_fw/core/tfm_secure_api.c b/secure_fw/core/tfm_secure_api.c
index 2c49717..eecb62e 100644
--- a/secure_fw/core/tfm_secure_api.c
+++ b/secure_fw/core/tfm_secure_api.c
@@ -14,16 +14,6 @@
  */
 int32_t tfm_secure_lock;
 
-int32_t tfm_bitcount(uint32_t n)
-{
-    uint8_t count = 0;
-    while (n) {
-        count++;
-        n &= n-1;
-    }
-    return (int32_t)count;
-}
-
 bool tfm_is_one_bit_set(uint32_t n)
 {
     return ((n && !(n & (n-1))) ? true : false);
diff --git a/secure_fw/spm/spm_ipc.c b/secure_fw/spm/spm_ipc.c
index ea1f735..ea3fa36 100644
--- a/secure_fw/spm/spm_ipc.c
+++ b/secure_fw/spm/spm_ipc.c
@@ -925,7 +925,7 @@
      * Only one message could be retrieved every time for psa_get(). It is a
      * fatal error if the input signal has more than a signal bit set.
      */
-    if (tfm_bitcount(signal) != 1) {
+    if (!tfm_is_one_bit_set(signal)) {
         tfm_core_panic();
     }