SPM: Introduce Secure Partition Manager

A Secure Partition is a software execution environment instantiated in
S-EL0 that can be used to implement simple management and security
services. Since S-EL0 is an unprivileged exception level, a Secure
Partition relies on privileged firmware e.g. ARM Trusted Firmware to be
granted access to system and processor resources. Essentially, it is a
software sandbox that runs under the control of privileged software in
the Secure World and accesses the following system resources:

- Memory and device regions in the system address map.
- PE system registers.
- A range of asynchronous exceptions e.g. interrupts.
- A range of synchronous exceptions e.g. SMC function identifiers.

A Secure Partition enables privileged firmware to implement only the
absolutely essential secure services in EL3 and instantiate the rest in
a partition. Since the partition executes in S-EL0, its implementation
cannot be overly complex.

The component in ARM Trusted Firmware responsible for managing a Secure
Partition is called the Secure Partition Manager (SPM). The SPM is
responsible for the following:

- Validating and allocating resources requested by a Secure Partition.
- Implementing a well defined interface that is used for initialising a
  Secure Partition.
- Implementing a well defined interface that is used by the normal world
  and other secure services for accessing the services exported by a
  Secure Partition.
- Implementing a well defined interface that is used by a Secure
  Partition to fulfil service requests.
- Instantiating the software execution environment required by a Secure
  Partition to fulfil a service request.

Change-Id: I6f7862d6bba8732db5b73f54e789d717a35e802f
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Achin Gupta <achin.gupta@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/services/std_svc/spm/spm_private.h b/services/std_svc/spm/spm_private.h
new file mode 100644
index 0000000..16993e8
--- /dev/null
+++ b/services/std_svc/spm/spm_private.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __SPM_PRIVATE_H__
+#define __SPM_PRIVATE_H__
+
+#include <context.h>
+
+/*******************************************************************************
+ * Constants that allow assembler code to preserve callee-saved registers of the
+ * C runtime context while performing a security state switch.
+ ******************************************************************************/
+#define SP_C_RT_CTX_X19		0x0
+#define SP_C_RT_CTX_X20		0x8
+#define SP_C_RT_CTX_X21		0x10
+#define SP_C_RT_CTX_X22		0x18
+#define SP_C_RT_CTX_X23		0x20
+#define SP_C_RT_CTX_X24		0x28
+#define SP_C_RT_CTX_X25		0x30
+#define SP_C_RT_CTX_X26		0x38
+#define SP_C_RT_CTX_X27		0x40
+#define SP_C_RT_CTX_X28		0x48
+#define SP_C_RT_CTX_X29		0x50
+#define SP_C_RT_CTX_X30		0x58
+
+#define SP_C_RT_CTX_SIZE	0x60
+#define SP_C_RT_CTX_ENTRIES	(SP_C_RT_CTX_SIZE >> DWORD_SHIFT)
+
+
+#ifndef __ASSEMBLY__
+
+#include <stdint.h>
+#include <xlat_tables_v2.h>
+
+/* Handle on the Secure partition translation context */
+extern xlat_ctx_t *secure_partition_xlat_ctx_handle;
+
+struct entry_point_info;
+
+typedef struct secure_partition_context {
+	uint64_t c_rt_ctx;
+	cpu_context_t cpu_ctx;
+} secure_partition_context_t;
+
+uint64_t spm_secure_partition_enter(uint64_t *c_rt_ctx);
+void __dead2 spm_secure_partition_exit(uint64_t c_rt_ctx, uint64_t ret);
+void spm_init_sp_ep_state(struct entry_point_info *sp_ep_info,
+			  uint64_t pc,
+			  secure_partition_context_t *sp_ctx_ptr);
+#endif /* __ASSEMBLY__ */
+
+#endif /* __SPM_PRIVATE_H__ */