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/bl2/bl2_main.c b/bl2/bl2_main.c
index 4745881..a3e0cdf 100644
--- a/bl2/bl2_main.c
+++ b/bl2/bl2_main.c
@@ -48,9 +48,7 @@
void bl2_main(void)
{
meminfo *bl2_tzram_layout;
- meminfo *bl31_tzram_layout;
- meminfo *bl33_ns_layout;
- el_change_info *ns_image_info;
+ bl31_args *bl2_to_bl31_args;
unsigned long bl31_base, bl33_base, el_status;
unsigned int bl2_load, bl31_load, mode;
@@ -60,7 +58,7 @@
/* Perform platform setup in BL1 */
bl2_platform_setup();
-#if defined (__GNUC__)
+#if defined(__GNUC__)
printf("BL2 Built : %s, %s\n\r", __TIME__, __DATE__);
#endif
@@ -80,19 +78,30 @@
bl31_load, BL31_BASE);
/* Assert if it has not been possible to load BL31 */
- assert(bl31_base != 0);
+ if (bl31_base == 0) {
+ ERROR("Failed to load BL3-1.\n");
+ panic();
+ }
+
+ /*
+ * Get a pointer to the memory the platform has set aside to pass
+ * information to BL31.
+ */
+ bl2_to_bl31_args = bl2_get_bl31_args_ptr();
/*
* Create a new layout of memory for BL31 as seen by BL2. This
* will gobble up all the BL2 memory.
*/
- bl31_tzram_layout = (meminfo *) get_el_change_mem_ptr();
- init_bl31_mem_layout(bl2_tzram_layout, bl31_tzram_layout, bl31_load);
+ init_bl31_mem_layout(bl2_tzram_layout,
+ &bl2_to_bl31_args->bl31_meminfo,
+ bl31_load);
- /* Find out where the BL3-3 normal world firmware should go. */
- bl33_ns_layout = bl2_get_ns_mem_layout();
- bl33_base = load_image(bl33_ns_layout, BL33_IMAGE_NAME,
- BOT_LOAD, plat_get_ns_image_entrypoint());
+ /* Load the BL33 image in non-secure memory provided by the platform */
+ bl33_base = load_image(&bl2_to_bl31_args->bl33_meminfo,
+ BL33_IMAGE_NAME,
+ BOT_LOAD,
+ plat_get_ns_image_entrypoint());
/* Halt if failed to load normal world firmware. */
if (bl33_base == 0) {
ERROR("Failed to load BL3-3.\n");
@@ -101,11 +110,9 @@
/*
* BL2 also needs to tell BL31 where the non-trusted software image
- * has been loaded. Place this info right after the BL31 memory layout
+ * is located.
*/
- ns_image_info = (el_change_info *) ((unsigned char *) bl31_tzram_layout
- + sizeof(meminfo));
- ns_image_info->entrypoint = bl33_base;
+ bl2_to_bl31_args->bl33_image_info.entrypoint = bl33_base;
/* Figure out what mode we enter the non-secure world in */
el_status = read_id_aa64pfr0_el1() >> ID_AA64PFR0_EL2_SHIFT;
@@ -116,22 +123,27 @@
else
mode = MODE_EL1;
- ns_image_info->spsr = make_spsr(mode, MODE_SP_ELX, MODE_RW_64);
- ns_image_info->security_state = NON_SECURE;
- flush_dcache_range((unsigned long) ns_image_info,
- sizeof(el_change_info));
+ /*
+ * TODO: Consider the possibility of specifying the SPSR in
+ * the FIP ToC and allowing the platform to have a say as
+ * well.
+ */
+ bl2_to_bl31_args->bl33_image_info.spsr =
+ make_spsr(mode, MODE_SP_ELX, MODE_RW_64);
+ bl2_to_bl31_args->bl33_image_info.security_state = NON_SECURE;
+
+ /* Flush the entire BL31 args buffer */
+ flush_dcache_range((unsigned long) bl2_to_bl31_args,
+ sizeof(*bl2_to_bl31_args));
/*
* Run BL31 via an SMC to BL1. Information on how to pass control to
- * the non-trusted software image will be passed to BL31 in x2.
+ * the BL32 (if present) and BL33 software images will be passed to
+ * BL31 as an argument.
*/
- if (bl31_base)
- run_image(bl31_base,
- make_spsr(MODE_EL3, MODE_SP_ELX, MODE_RW_64),
- SECURE,
- bl31_tzram_layout,
- (void *) ns_image_info);
-
- /* There is no valid reason for run_image() to return */
- assert(0);
+ run_image(bl31_base,
+ make_spsr(MODE_EL3, MODE_SP_ELX, MODE_RW_64),
+ SECURE,
+ (void *) bl2_to_bl31_args,
+ NULL);
}