diff --git a/tests/suites/test_suite_entropy.data b/tests/suites/test_suite_entropy.data
index 833eef5..5ca99f8 100644
--- a/tests/suites/test_suite_entropy.data
+++ b/tests/suites/test_suite_entropy.data
@@ -1,3 +1,6 @@
+Create NV seed_file
+nv_seed_file_create:
+
 Entropy write/update seed file
 entropy_seed_file:"data_files/entropy_seed":0
 
@@ -37,5 +40,17 @@
 Entropy thershold #4
 entropy_threshold:1024:1:MBEDTLS_ERR_ENTROPY_SOURCE_FAILED
 
+Check NV seed standard IO
+entropy_nv_seed_std_io:
+
+Check NV seed manually #1
+entropy_nv_seed:"00112233445566778899AABBCCDDEEFF00112233445566778899AABBCCDDEEFF00112233445566778899AABBCCDDEEFF00112233445566778899AABBCCDDEEFF"
+
+Check NV seed manually #2
+entropy_nv_seed:"00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+
+Check NV seed manually #3
+entropy_nv_seed:"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
+
 Entropy self test
 entropy_selftest:
diff --git a/tests/suites/test_suite_entropy.function b/tests/suites/test_suite_entropy.function
index 3b739cc..999b5f6 100644
--- a/tests/suites/test_suite_entropy.function
+++ b/tests/suites/test_suite_entropy.function
@@ -1,5 +1,6 @@
 /* BEGIN_HEADER */
 #include "mbedtls/entropy.h"
+#include "mbedtls/entropy_poll.h"
 
 /*
  * Number of calls made to entropy_dummy_source()
@@ -33,6 +34,86 @@
 
     return( 0 );
 }
+
+/*
+ * Ability to clear entropy sources to allow testing with just predefined
+ * entropy sources. This function or tests depending on it might break if there
+ * are internal changes to how entropy sources are registered.
+ *
+ * To be called immediately after mbedtls_entropy_init().
+ *
+ * Just resetting the counter. New sources will overwrite existing ones.
+ * This might break memory checks in the future if sources need 'free-ing' then
+ * as well.
+ */
+static void entropy_clear_sources( mbedtls_entropy_context *ctx )
+{
+    ctx->source_count = 0;
+}
+
+/*
+ * NV seed read/write functions that use a buffer instead of a file
+ */
+static unsigned char buffer_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
+
+static int buffer_nv_seed_read( unsigned char *buf, size_t buf_len )
+{
+    if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    memcpy( buf, buffer_seed, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    return( 0 );
+}
+
+static int buffer_nv_seed_write( unsigned char *buf, size_t buf_len )
+{
+    if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    memcpy( buffer_seed, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    return( 0 );
+}
+
+/*
+ * NV seed read/write helpers that fill the base seedfile
+ */
+static int write_nv_seed( unsigned char *buf, size_t buf_len )
+{
+    FILE *f;
+
+    if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    if( ( f = fopen( MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "w" ) ) == NULL )
+        return( -1 );
+
+    if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) !=
+                    MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    fclose( f );
+
+    return( 0 );
+}
+
+static int read_nv_seed( unsigned char *buf, size_t buf_len )
+{
+    FILE *f;
+
+    if( buf_len != MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    if( ( f = fopen( MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "rb" ) ) == NULL )
+        return( -1 );
+
+    if( fread( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) !=
+                    MBEDTLS_ENTROPY_BLOCK_SIZE )
+        return( -1 );
+
+    fclose( f );
+
+    return( 0 );
+}
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
@@ -160,6 +241,10 @@
     if( result >= 0 )
     {
         TEST_ASSERT( ret == 0 );
+#if defined(MBEDTLS_ENTROPY_NV_SEED)
+        // Two times as much calls due to the NV seed update
+        result *= 2;
+#endif
         TEST_ASSERT( entropy_dummy_calls == (size_t) result );
     }
     else
@@ -172,6 +257,124 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_FS_IO */
+void nv_seed_file_create()
+{
+    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
+
+    memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    TEST_ASSERT( write_nv_seed( buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_FS_IO */
+void entropy_nv_seed_std_io()
+{
+    unsigned char io_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char check_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
+
+    memset( io_seed, 1, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( check_seed, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    mbedtls_platform_set_nv_seed( mbedtls_platform_std_nv_seed_read,
+                                  mbedtls_platform_std_nv_seed_write );
+
+    /* Check if platform NV read and write manipulate the same data */
+    TEST_ASSERT( write_nv_seed( io_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+    TEST_ASSERT( mbedtls_nv_seed_read( check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) ==
+                    MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    TEST_ASSERT( memcmp( io_seed, check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+
+    memset( check_seed, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    /* Check if platform NV write and raw read manipulate the same data */
+    TEST_ASSERT( mbedtls_nv_seed_write( io_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) ==
+                    MBEDTLS_ENTROPY_BLOCK_SIZE );
+    TEST_ASSERT( read_nv_seed( check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+
+    TEST_ASSERT( memcmp( io_seed, check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:MBEDTLS_PLATFORM_NV_SEED_ALT:MBEDTLS_SHA512_C */
+void entropy_nv_seed( char *read_seed_str )
+{
+    mbedtls_sha512_context accumulator;
+    mbedtls_entropy_context ctx;
+
+    unsigned char header[2];
+    unsigned char entropy[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char empty[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char read_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char check_seed[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    unsigned char check_entropy[MBEDTLS_ENTROPY_BLOCK_SIZE];
+
+    memset( entropy, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( buffer_seed, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( empty, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( check_seed, 2, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    memset( check_entropy, 3, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    // Set the initial NV seed to read
+    unhexify( read_seed, read_seed_str );
+    memcpy( buffer_seed, read_seed, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    // Make sure we read/write NV seed from our buffers
+    mbedtls_platform_set_nv_seed( buffer_nv_seed_read, buffer_nv_seed_write );
+
+    mbedtls_entropy_init( &ctx );
+    entropy_clear_sources( &ctx );
+
+    TEST_ASSERT( mbedtls_entropy_add_source( &ctx, mbedtls_nv_seed_poll, NULL,
+                                             MBEDTLS_ENTROPY_BLOCK_SIZE,
+                                             MBEDTLS_ENTROPY_SOURCE_STRONG ) == 0 );
+
+    // Do an entropy run
+    TEST_ASSERT( mbedtls_entropy_func( &ctx, entropy, sizeof( entropy ) ) == 0 );
+
+    // Determine what should have happened with manual entropy internal logic
+    // Only use the SHA-512 version to check
+
+    // Init accumulator
+    header[1] = MBEDTLS_ENTROPY_BLOCK_SIZE;
+    mbedtls_sha512_starts( &accumulator, 0 );
+
+    // First run for updating write_seed
+    header[0] = 0;
+    mbedtls_sha512_update( &accumulator, header, 2 );
+    mbedtls_sha512_update( &accumulator, read_seed, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    mbedtls_sha512_finish( &accumulator, buf );
+
+    memset( &accumulator, 0, sizeof( mbedtls_sha512_context ) );
+    mbedtls_sha512_starts( &accumulator, 0 );
+    mbedtls_sha512_update( &accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, check_seed, 0 );
+
+    // Second run for actual entropy (triggers mbedtls_entropy_update_nv_seed)
+    header[0] = MBEDTLS_ENTROPY_SOURCE_MANUAL;
+    mbedtls_sha512_update( &accumulator, header, 2 );
+    mbedtls_sha512_update( &accumulator, empty, MBEDTLS_ENTROPY_BLOCK_SIZE );
+
+    header[0] = 0;
+    mbedtls_sha512_update( &accumulator, header, 2 );
+    mbedtls_sha512_update( &accumulator, check_seed, MBEDTLS_ENTROPY_BLOCK_SIZE );
+    mbedtls_sha512_finish( &accumulator, buf );
+
+    mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, check_entropy, 0 );
+
+    // Check result of both NV file and entropy received with the manual calculations
+    TEST_ASSERT( memcmp( check_seed, buffer_seed, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+    TEST_ASSERT( memcmp( check_entropy, entropy, MBEDTLS_ENTROPY_BLOCK_SIZE ) == 0 );
+
+    mbedtls_entropy_free( &ctx );
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_SELF_TEST */
 void entropy_selftest( )
 {