diff --git a/tests/src/helpers.c b/tests/src/helpers.c
index 6c215d1..198a9c0 100644
--- a/tests/src/helpers.c
+++ b/tests/src/helpers.c
@@ -24,6 +24,11 @@
 #include <setjmp.h>
 #endif
 
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY)
+#include <psa/crypto.h>
+#include <test/psa_crypto_helpers.h>
+#endif
+
 /*----------------------------------------------------------------------------*/
 /* Static global variables */
 
@@ -52,9 +57,22 @@
 int mbedtls_test_platform_setup(void)
 {
     int ret = 0;
+
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY)
+    /* Make sure that injected entropy is present. Otherwise
+     * psa_crypto_init() will fail. This is not necessary for test suites
+     * that don't use PSA, but it's harmless (except for leaving a file
+     * behind). */
+    ret = mbedtls_test_inject_entropy_restore();
+    if (ret != 0) {
+        return ret;
+    }
+#endif
+
 #if defined(MBEDTLS_PLATFORM_C)
     ret = mbedtls_platform_setup(&platform_ctx);
 #endif /* MBEDTLS_PLATFORM_C */
+
     return ret;
 }
 
diff --git a/tests/src/psa_crypto_helpers.c b/tests/src/psa_crypto_helpers.c
index 7861185..cab96ab 100644
--- a/tests/src/psa_crypto_helpers.c
+++ b/tests/src/psa_crypto_helpers.c
@@ -178,6 +178,20 @@
     return 0;
 }
 
+int mbedtls_test_inject_entropy_restore(void)
+{
+    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
+    for (size_t i = 0; i < sizeof(buf); i++) {
+        buf[i] = (unsigned char) i;
+    }
+    psa_status_t status = mbedtls_psa_inject_entropy(buf, sizeof(buf));
+    /* It's ok if the file was just created, or if it already exists. */
+    if (status != PSA_SUCCESS && status != PSA_ERROR_NOT_PERMITTED) {
+        return status;
+    }
+    return PSA_SUCCESS;
+}
+
 #endif /* MBEDTLS_PSA_INJECT_ENTROPY */
 
 #endif /* MBEDTLS_PSA_CRYPTO_C */