ARM: add basic support for Trusted Foundations

Trusted Foundations is a TrustZone-based secure monitor for ARM that
can be invoked using the same SMC-based API on supported platforms.
This patch adds initial basic support for Trusted Foundations using
the ARM firmware API. Current features are limited to the ability to
boot secondary processors.

Note: The API followed by Trusted Foundations does *not* follow the SMC
calling conventions. It has nothing to do with PSCI neither and is only
relevant to devices that use Trusted Foundations (like most Tegra-based
retail devices).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h
new file mode 100644
index 0000000..3bd36e2
--- /dev/null
+++ b/arch/arm/include/asm/trusted_foundations.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2013, NVIDIA Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+/*
+ * Support for the Trusted Foundations secure monitor.
+ *
+ * Trusted Foundation comes active on some ARM consumer devices (most
+ * Tegra-based devices sold on the market are concerned). Such devices can only
+ * perform some basic operations, like setting the CPU reset vector, through
+ * SMC calls to the secure monitor. The calls are completely specific to
+ * Trusted Foundations, and do *not* follow the SMC calling convention or the
+ * PSCI standard.
+ */
+
+#ifndef __ASM_ARM_TRUSTED_FOUNDATIONS_H
+#define __ASM_ARM_TRUSTED_FOUNDATIONS_H
+
+#include <linux/kconfig.h>
+#include <linux/printk.h>
+#include <linux/bug.h>
+#include <linux/of.h>
+
+struct trusted_foundations_platform_data {
+	unsigned int version_major;
+	unsigned int version_minor;
+};
+
+#if IS_ENABLED(CONFIG_TRUSTED_FOUNDATIONS)
+
+void register_trusted_foundations(struct trusted_foundations_platform_data *pd);
+void of_register_trusted_foundations(void);
+
+#else /* CONFIG_TRUSTED_FOUNDATIONS */
+
+static inline void register_trusted_foundations(
+				   struct trusted_foundations_platform_data *pd)
+{
+	/*
+	 * If we try to register TF, this means the system needs it to continue.
+	 * Its absence if thus a fatal error.
+	 */
+	panic("No support for Trusted Foundations, stopping...\n");
+}
+
+static inline void of_register_trusted_foundations(void)
+{
+	/*
+	 * If we find the target should enable TF but does not support it,
+	 * fail as the system won't be able to do much anyway
+	 */
+	if (of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"))
+		register_trusted_foundations(NULL);
+}
+#endif /* CONFIG_TRUSTED_FOUNDATIONS */
+
+#endif