bsps/shared: Add PSCI-based bspreset implementation

This adds a bsp_reset implementation based on the ARM PSCI
specification often present in ARMv8 systems.

bsps/shared/start/bspreset-arm-psci.c

@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSBSPsShared
+ *
+ * @brief PSCI-based BSP reset hook.
+ */
+
+/*
+ * Copyright (C) 2020 On-Line Applications Research Corporation (OAR)
+ * Written by Kinsey Moore <kinsey.moore@oarcorp.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <bsp.h>
+#include <bsp/bootcard.h>
+
+void bsp_reset(void)
+{
+	uint32_t PSCI_FN_SYSTEM_RESET = 0x84000009;
+	__asm__ volatile(
+#if defined(AARCH64_MULTILIB_ARCH_V8) || defined(AARCH64_MULTILIB_ARCH_V8_ILP32)
+		"mov x0, %0\n"
+#else
+		"mov r0, %0\n"
+#endif
+#ifdef BSP_RESET_SMC
+		"smc #0\n"
+#else
+		"hvc #0\n"
+#endif
+		: : "r" (PSCI_FN_SYSTEM_RESET)
+	);
+}