4 files changed, 48 insertions, 28 deletions
diff --git a/plat/rpi/common/rpi3_common.c b/plat/rpi/common/rpi3_common.c
index 4317b3a26..ff3369427 100644
--- a/plat/rpi/common/rpi3_common.c
+++ b/plat/rpi/common/rpi3_common.c
@@ -176,18 +176,6 @@ void rpi3_setup_page_tables(uintptr_t total_base, size_t total_size,
 }
 
 /*******************************************************************************
- * Return entrypoint of BL33.
- ******************************************************************************/
-uintptr_t plat_get_ns_image_entrypoint(void)
-{
-#ifdef PRELOADED_BL33_BASE
-	return PRELOADED_BL33_BASE;
-#else
-	return PLAT_RPI3_NS_IMAGE_OFFSET;
-#endif
-}
-
-/*******************************************************************************
  * Gets SPSR for BL32 entry
  ******************************************************************************/
 uint32_t rpi3_get_spsr_for_bl32_entry(void)
diff --git a/plat/rpi/rpi3/rpi3_bl31_setup.c b/plat/rpi/rpi3/rpi3_bl31_setup.c
index c16dbffaa..24a56139b 100644
--- a/plat/rpi/rpi3/rpi3_bl31_setup.c
+++ b/plat/rpi/rpi3/rpi3_bl31_setup.c
@@ -48,6 +48,18 @@ entry_point_info_t *bl31_plat_get_next_image_ep_info(uint32_t type)
 }
 
 /*******************************************************************************
+ * Return entrypoint of BL33.
+ ******************************************************************************/
+uintptr_t plat_get_ns_image_entrypoint(void)
+{
+#ifdef PRELOADED_BL33_BASE
+	return PRELOADED_BL33_BASE;
+#else
+	return PLAT_RPI3_NS_IMAGE_OFFSET;
+#endif
+}
+
+/*******************************************************************************
  * Perform any BL31 early platform setup. Here is an opportunity to copy
  * parameters passed by the calling EL (S-EL1 in BL2 & EL3 in BL1) before
  * they are lost (potentially). This needs to be done before the MMU is
diff --git a/plat/rpi/rpi4/platform.mk b/plat/rpi/rpi4/platform.mk
index b20251cf4..6ac21691e 100644
--- a/plat/rpi/rpi4/platform.mk
+++ b/plat/rpi/rpi4/platform.mk
@@ -68,8 +68,8 @@ USE_COHERENT_MEM		:= 1
 # Platform build flags
 # --------------------
 
-# Assume that BL33 isn't the Linux kernel by default
-RPI3_DIRECT_LINUX_BOOT		:= 0
+# There is not much else than a Linux kernel to load at the moment.
+RPI3_DIRECT_LINUX_BOOT		:= 1
 
 # BL33 images are in AArch64 by default
 RPI3_BL33_IN_AARCH32		:= 0
@@ -92,15 +92,6 @@ endif
 $(eval $(call add_define,RPI3_RUNTIME_UART))
 $(eval $(call add_define,RPI3_USE_UEFI_MAP))
 
-# Verify build config
-# -------------------
-#
-ifneq (${RPI3_DIRECT_LINUX_BOOT}, 0)
-  ifndef RPI3_PRELOADED_DTB_BASE
-      $(error Error: RPI3_PRELOADED_DTB_BASE needed if RPI3_DIRECT_LINUX_BOOT=1)
-  endif
-endif
-
 ifeq (${ARCH},aarch32)
   $(error Error: AArch32 not supported on rpi4)
 endif
diff --git a/plat/rpi/rpi4/rpi4_bl31_setup.c b/plat/rpi/rpi4/rpi4_bl31_setup.c
index 58025b27a..f5f74bdd2 100644
--- a/plat/rpi/rpi4/rpi4_bl31_setup.c
+++ b/plat/rpi/rpi4/rpi4_bl31_setup.c
@@ -27,6 +27,8 @@
  * confirmation and puts the kernel and DT address in the following words.
  */
 extern uint32_t stub_magic;
+extern uint32_t dtb_ptr32;
+extern uint32_t kernel_entry32;
 
 static const gicv2_driver_data_t rpi4_gic_data = {
 	.gicd_base = RPI4_GIC_GICD_BASE,
@@ -63,6 +65,34 @@ entry_point_info_t *bl31_plat_get_next_image_ep_info(uint32_t type)
 	}
 }
 
+uintptr_t plat_get_ns_image_entrypoint(void)
+{
+#ifdef PRELOADED_BL33_BASE
+	return PRELOADED_BL33_BASE;
+#else
+	/* Cleared by the GPU if kernel address is valid. */
+	if (stub_magic == 0)
+		return kernel_entry32;
+
+	WARN("Stub magic failure, using default kernel address 0x80000\n");
+	return 0x80000;
+#endif
+}
+
+static uintptr_t rpi4_get_dtb_address(void)
+{
+#ifdef RPI3_PRELOADED_DTB_BASE
+	return RPI3_PRELOADED_DTB_BASE;
+#else
+	/* Cleared by the GPU if DTB address is valid. */
+	if (stub_magic == 0)
+		return dtb_ptr32;
+
+	WARN("Stub magic failure, DTB address unknown\n");
+	return 0;
+#endif
+}
+
 static void ldelay(register_t delay)
 {
 	__asm__ volatile (
@@ -114,12 +144,11 @@ void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
 		div_reg = 1;
 	rpi3_console_init(PLAT_RPI4_VPU_CLK_RATE / div_reg);
 
-#if RPI3_DIRECT_LINUX_BOOT
 	bl33_image_ep_info.pc = plat_get_ns_image_entrypoint();
-	bl33_image_ep_info.spsr = SPSR_64(MODE_EL2, MODE_SP_ELX,
-					  DISABLE_ALL_EXCEPTIONS);
+	bl33_image_ep_info.spsr = rpi3_get_spsr_for_bl33_entry();
 	SET_SECURITY_STATE(bl33_image_ep_info.h.attr, NON_SECURE);
 
+#if RPI3_DIRECT_LINUX_BOOT
 # if RPI3_BL33_IN_AARCH32
 	/*
 	 * According to the file ``Documentation/arm/Booting`` of the Linux
@@ -131,7 +160,7 @@ void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
 	VERBOSE("rpi4: Preparing to boot 32-bit Linux kernel\n");
 	bl33_image_ep_info.args.arg0 = 0U;
 	bl33_image_ep_info.args.arg1 = ~0U;
-	bl33_image_ep_info.args.arg2 = (u_register_t) RPI3_PRELOADED_DTB_BASE;
+	bl33_image_ep_info.args.arg2 = rpi4_get_dtb_address();
 # else
 	/*
 	 * According to the file ``Documentation/arm64/booting.txt`` of the
@@ -140,7 +169,7 @@ void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
 	 * must be 0.
 	 */
 	VERBOSE("rpi4: Preparing to boot 64-bit Linux kernel\n");
-	bl33_image_ep_info.args.arg0 = (u_register_t) RPI3_PRELOADED_DTB_BASE;
+	bl33_image_ep_info.args.arg0 = rpi4_get_dtb_address();
 	bl33_image_ep_info.args.arg1 = 0ULL;
 	bl33_image_ep_info.args.arg2 = 0ULL;
 	bl33_image_ep_info.args.arg3 = 0ULL;