Add TRNG Firmware Interface service
This adds the TRNG Firmware Interface Service to the standard
service dispatcher. This includes a method for dispatching entropy
requests to platforms and includes an entropy pool implementation to
avoid dropping any entropy requested from the platform.
Change-Id: I71cadb3cb377a507652eca9e0d68714c973026e9
Signed-off-by: Jimmy Brisson <jimmy.brisson@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/include/services/trng_svc.h b/include/services/trng_svc.h
new file mode 100644
index 0000000..ed4d557
--- /dev/null
+++ b/include/services/trng_svc.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2021, ARM Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef TRNG_SVC_H
+#define TRNG_SVC_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <lib/smccc.h>
+
+/* SMC function IDs for TRNG queries */
+#define ARM_TRNG_VERSION U(0x84000050)
+#define ARM_TRNG_FEATURES U(0x84000051)
+#define ARM_TRNG_GET_UUID U(0x84000052)
+#define ARM_TRNG_RND32 U(0x84000053)
+#define ARM_TRNG_RND64 U(0xc4000053)
+
+/* TRNG version numbers */
+#define TRNG_VERSION_MAJOR (0x1)
+#define TRNG_VERSION_MINOR (0x0)
+
+/* TRNG Error Numbers */
+#define TRNG_E_SUCCESS (0)
+#define TRNG_E_NOT_SUPPORTED (-1)
+#define TRNG_E_INVALID_PARAMS (-2)
+#define TRNG_E_NO_ENTROPY (-3)
+#define TRNG_E_NOT_IMPLEMENTED (-4)
+
+#if TRNG_SUPPORT
+void trng_setup(void);
+bool is_trng_fid(uint32_t smc_fid);
+#else
+static inline void trng_setup(void)
+{
+}
+
+static inline bool is_trng_fid(uint32_t smc_fid)
+{
+ return false;
+}
+#endif
+uintptr_t trng_smc_handler(
+ uint32_t smc_fid,
+ u_register_t x1,
+ u_register_t x2,
+ u_register_t x3,
+ u_register_t x4,
+ void *cookie,
+ void *handle,
+ u_register_t flags
+);
+
+#endif /* TRNG_SVC_H */