Enable preloaded BL33 alternative boot flow
Enable alternative boot flow where BL2 does not load BL33 from
non-volatile storage, and BL31 hands execution over to a preloaded
BL33.
The flag used to enable this bootflow is BL33_BASE, which must hold
the entrypoint address of the BL33 image. The User Guide has been
updated with an example of how to use this option with a bootwrapped
kernel.
Change-Id: I48087421a7b0636ac40dca7d457d745129da474f
diff --git a/bl2/bl2_main.c b/bl2/bl2_main.c
index 9ff75d2..73781dd 100644
--- a/bl2/bl2_main.c
+++ b/bl2/bl2_main.c
@@ -169,6 +169,7 @@
return e;
}
+#ifndef BL33_BASE
/*******************************************************************************
* Load the BL33 image.
* The bl2_to_bl31_params param will be updated with the relevant BL33
@@ -199,6 +200,8 @@
return e;
}
+#endif /* BL33_BASE */
+
#endif /* EL3_PAYLOAD_BASE */
/*******************************************************************************
@@ -253,7 +256,7 @@
* bl31_params_t structure makes sense in the context of EL3 payloads.
* This will be refined in the future.
*/
- VERBOSE("BL2: Populating the entrypoint info for the EL3 payload\n");
+ INFO("BL2: Populating the entrypoint info for the EL3 payload\n");
bl31_ep_info->pc = EL3_PAYLOAD_BASE;
bl31_ep_info->args.arg0 = (unsigned long) bl2_to_bl31_params;
bl2_plat_set_bl31_ep_info(NULL, bl31_ep_info);
@@ -274,11 +277,22 @@
}
}
+#ifdef BL33_BASE
+ /*
+ * In this case, don't load the BL33 image as it's already loaded in
+ * memory. Update BL33 entrypoint information.
+ */
+ INFO("BL2: Populating the entrypoint info for the preloaded BL33\n");
+ bl2_to_bl31_params->bl33_ep_info->pc = BL33_BASE;
+ bl2_plat_set_bl33_ep_info(NULL, bl2_to_bl31_params->bl33_ep_info);
+#else
e = load_bl33(bl2_to_bl31_params);
if (e) {
ERROR("Failed to load BL33 (%i)\n", e);
plat_error_handler(e);
}
+#endif /* BL33_BASE */
+
#endif /* EL3_PAYLOAD_BASE */
/* Flush the params to be passed to memory */