Factor out cross-BL API into export headers suitable for 3rd party code
This patch adds a new include/export/ directory meant for inclusion in
third-party code. This is useful for cases where third-party code needs
to interact with TF-A interfaces and data structures (such as a custom
BL2-implementation like coreboot handing off to BL31). Directly
including headers from the TF-A repository avoids having to duplicate
all these definitions (and risk them going stale), but with the current
header structure this is not possible because handoff API definitions
are too deeply intertwined with other TF code/headers and chain-include
other headers that will not be available in the other environment.
The new approach aims to solve this by separating only the parts that
are really needed into these special headers that are self-contained and
will not chain-include other (non-export) headers. TF-A code should
never include them directly but should instead always include the
respective wrapper header, which will include the required prerequisites
(like <stdint.h>) before including the export header. Third-party code
can include the export headers via its own wrappers that make sure the
necessary definitions are available in whatever way that environment can
provide them.
Change-Id: Ifd769320ba51371439a8e5dd5b79c2516c3b43ab
Signed-off-by: Julius Werner <jwerner@chromium.org>
diff --git a/include/export/common/ep_info_exp.h b/include/export/common/ep_info_exp.h
new file mode 100644
index 0000000..4c703e6
--- /dev/null
+++ b/include/export/common/ep_info_exp.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef ARM_TRUSTED_FIRMWARE_EXPORT_COMMON_EP_INFO_EXP_H
+#define ARM_TRUSTED_FIRMWARE_EXPORT_COMMON_EP_INFO_EXP_H
+
+/* EXPORT HEADER -- See include/export/README for details! -- EXPORT HEADER */
+
+#include "../lib/utils_def_exp.h"
+#include "param_header_exp.h"
+
+/*******************************************************************************
+ * Constants that allow assembler code to access members of and the
+ * 'entry_point_info' structure at their correct offsets.
+ ******************************************************************************/
+#define ENTRY_POINT_INFO_PC_OFFSET U(0x08)
+#ifdef __aarch64__
+#define ENTRY_POINT_INFO_ARGS_OFFSET U(0x18)
+#else
+#define ENTRY_POINT_INFO_LR_SVC_OFFSET U(0x10)
+#define ENTRY_POINT_INFO_ARGS_OFFSET U(0x14)
+#endif
+
+/* Security state of the image. */
+#define EP_SECURITY_MASK U(0x1)
+#define EP_SECURITY_SHIFT U(0)
+#define EP_SECURE U(0x0)
+#define EP_NON_SECURE U(0x1)
+
+/* Endianness of the image. */
+#define EP_EE_MASK U(0x2)
+#define EP_EE_SHIFT U(1)
+#define EP_EE_LITTLE U(0x0)
+#define EP_EE_BIG U(0x2)
+#define EP_GET_EE(x) ((x) & EP_EE_MASK)
+#define EP_SET_EE(x, ee) ((x) = ((x) & ~EP_EE_MASK) | (ee))
+
+/* Enable or disable access to the secure timer from secure images. */
+#define EP_ST_MASK U(0x4)
+#define EP_ST_SHIFT U(2)
+#define EP_ST_DISABLE U(0x0)
+#define EP_ST_ENABLE U(0x4)
+#define EP_GET_ST(x) ((x) & EP_ST_MASK)
+#define EP_SET_ST(x, ee) ((x) = ((x) & ~EP_ST_MASK) | (ee))
+
+/* Determine if an image is executable or not. */
+#define EP_EXE_MASK U(0x8)
+#define EP_EXE_SHIFT U(3)
+#define EP_NON_EXECUTABLE U(0x0)
+#define EP_EXECUTABLE U(0x8)
+#define EP_GET_EXE(x) ((x) & EP_EXE_MASK)
+#define EP_SET_EXE(x, ee) ((x) = ((x) & ~EP_EXE_MASK) | (ee))
+
+/* Flag to indicate the first image that is executed. */
+#define EP_FIRST_EXE_MASK U(0x10)
+#define EP_FIRST_EXE_SHIFT U(4)
+#define EP_FIRST_EXE U(0x10)
+#define EP_GET_FIRST_EXE(x) ((x) & EP_FIRST_EXE_MASK)
+#define EP_SET_FIRST_EXE(x, ee) ((x) = ((x) & ~EP_FIRST_EXE_MASK) | (ee))
+
+#ifndef __ASSEMBLER__
+
+typedef struct aapcs64_params {
+ uint64_t arg0;
+ uint64_t arg1;
+ uint64_t arg2;
+ uint64_t arg3;
+ uint64_t arg4;
+ uint64_t arg5;
+ uint64_t arg6;
+ uint64_t arg7;
+} aapcs64_params_t;
+
+typedef struct aapcs32_params {
+ uint32_t arg0;
+ uint32_t arg1;
+ uint32_t arg2;
+ uint32_t arg3;
+} aapcs32_params_t;
+
+/*****************************************************************************
+ * This structure represents the superset of information needed while
+ * switching exception levels. The only two mechanisms to do so are
+ * ERET & SMC. Security state is indicated using bit zero of header
+ * attribute
+ * NOTE: BL1 expects entrypoint followed by spsr at an offset from the start
+ * of this structure defined by the macro `ENTRY_POINT_INFO_PC_OFFSET` while
+ * processing SMC to jump to BL31.
+ *****************************************************************************/
+typedef struct entry_point_info {
+ param_header_t h;
+ uintptr_t pc;
+ uint32_t spsr;
+#ifdef __aarch64__
+ aapcs64_params_t args;
+#else
+ uintptr_t lr_svc;
+ aapcs32_params_t args;
+#endif
+} entry_point_info_t;
+
+#endif /*__ASSEMBLER__*/
+
+#endif /* ARM_TRUSTED_FIRMWARE_EXPORT_COMMON_EP_INFO_EXP_H */