Rework BL2 to BL3-1 hand over interface
This patch reworks BL2 to BL3-1 hand over interface by introducing a
composite structure (bl31_args) that holds the superset of information
that needs to be passed from BL2 to BL3-1.
- The extents of secure memory available to BL3-1
- The extents of memory available to BL3-2 (not yet implemented) and
BL3-3
- Information to execute BL3-2 (not yet implemented) and BL3-3 images
This patch also introduces a new platform API (bl2_get_bl31_args_ptr)
that needs to be implemented by the platform code to export reference to
bl31_args structure which has been allocated in platform-defined memory.
The platform will initialize the extents of memory available to BL3-3
during early platform setup in bl31_args structure. This obviates the
need for bl2_get_ns_mem_layout platform API.
BL2 calls the bl2_get_bl31_args_ptr function to get a reference to
bl31_args structure. It uses the 'bl33_meminfo' field of this structure
to load the BL3-3 image. It sets the entry point information for the
BL3-3 image in the 'bl33_image_info' field of this structure. The
reference to this structure is passed to the BL3-1 image.
Also fixes issue ARM-software/tf-issues#25
Change-Id: Ic36426196dd5ebf89e60ff42643bed01b3500517
diff --git a/include/bl_common.h b/include/bl_common.h
index 2d1d0db..aad3d22 100644
--- a/include/bl_common.h
+++ b/include/bl_common.h
@@ -49,21 +49,6 @@
#define LOAD_MASK (1 << 0)
/*******************************************************************************
- * Size of memory for sharing data while changing exception levels.
- *
- * There are 2 cases where this memory buffer is used:
- *
- * - when BL1 (running in EL3) passes control to BL2 (running in S-EL1).
- * BL1 needs to pass the memory layout to BL2, to allow BL2 to find out
- * how much free trusted ram remains;
- *
- * - when BL2 (running in S-EL1) passes control back to BL1 (running in EL3)
- * to make it run BL31. BL2 needs to pass the memory layout, as well as
- * information on how to pass control to the non-trusted software image.
- ******************************************************************************/
-#define EL_CHANGE_MEM_SIZE (sizeof(meminfo) + sizeof(el_change_info))
-
-/*******************************************************************************
* Macro to flag a compile time assertion. It uses the preprocessor to generate
* an invalid C construct if 'cond' evaluates to false.
* The following compilation error is triggered if the assertion fails:
@@ -81,6 +66,8 @@
#ifndef __ASSEMBLY__
+#include <stdio.h>
+
/*******************************************************************************
* Structure used for telling the next BL how much of a particular type of
* memory is available for its use and how much is already used.
@@ -108,27 +95,36 @@
/*******************************************************************************
* This structure represents the superset of information needed while switching
* exception levels. The only two mechanisms to do so are ERET & SMC. In case of
- * SMC all members apart from 'aapcs64_params' will be ignored. The 'next'
- * member is a placeholder for a complicated case in the distant future when BL2
- * will load multiple BL3x images as well as a non-secure image. So multiple
- * such structures will have to be passed to BL31 in S-EL3.
+ * SMC all members apart from 'aapcs64_params' will be ignored.
******************************************************************************/
typedef struct {
unsigned long entrypoint;
unsigned long spsr;
unsigned long security_state;
aapcs64_params args;
- unsigned long next;
} el_change_info;
/*******************************************************************************
+ * This structure represents the superset of information that can be passed to
+ * BL31 e.g. while passing control to it from BL2. The BL32 parameters will be
+ * populated only if BL2 detects its presence.
+ ******************************************************************************/
+typedef struct {
+ meminfo bl31_meminfo;
+ el_change_info bl32_image_info;
+ meminfo bl32_meminfo;
+ el_change_info bl33_image_info;
+ meminfo bl33_meminfo;
+} bl31_args;
+
+/*******************************************************************************
* Function & variable prototypes
******************************************************************************/
extern unsigned long page_align(unsigned long, unsigned);
extern void change_security_state(unsigned int);
-extern int drop_el(aapcs64_params *, unsigned long, unsigned long);
-extern long raise_el(aapcs64_params *);
-extern long change_el(el_change_info *);
+extern void __dead2 drop_el(aapcs64_params *, unsigned long, unsigned long);
+extern void __dead2 raise_el(aapcs64_params *);
+extern void __dead2 change_el(el_change_info *);
extern unsigned long make_spsr(unsigned long, unsigned long, unsigned long);
extern void init_bl2_mem_layout(meminfo *,
meminfo *,
@@ -138,11 +134,11 @@
meminfo *,
unsigned int) __attribute__((weak));
extern unsigned long load_image(meminfo *, const char *, unsigned int, unsigned long);
-extern int run_image(unsigned long,
- unsigned long,
- unsigned long,
- meminfo *,
- void *);
+extern void __dead2 run_image(unsigned long entrypoint,
+ unsigned long spsr,
+ unsigned long security_state,
+ void *first_arg,
+ void *second_arg);
extern unsigned long *get_el_change_mem_ptr(void);
#endif /*__ASSEMBLY__*/