plat/arm/juno: Add support to use hw_config in BL31

To make it possible to use the hw_config device tree for dynamic
configuration in BL31 on the Arm Juno platform. A placeholder hw_config
has been added that is included in the FIP and a Juno specific BL31
setup has been added to populate fconf with the hw_config.

Juno's BL2 setup has been updated to align it with the new behavior
implemented in the Arm FVP platform, where fw_config is passed in arg1
to BL31 instead of soc_fw_config. The BL31 setup is expected to use the
fw_config passed in arg1 to find the hw_config.

Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>
Change-Id: Ib3570faa6714f92ab8451e8f1e59779dcf19c0b6

docs/getting_started/porting-guide.rst

@@ -1742,9 +1742,9 @@ In Arm standard platforms, the arguments received are :
     which is list of executable images following BL31,
 
     arg1 - Points to load address of SOC_FW_CONFIG if present
-           except in case of Arm FVP platform.
+           except in case of Arm FVP and Juno platform.
 
-           In case of Arm FVP platform, Points to load address
+           In case of Arm FVP and Juno platform, points to load address
            of FW_CONFIG.
 
     arg2 - Points to load address of HW_CONFIG if present

fdts/juno.dts

@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/dts-v1/;
+
+/ {
+
+};

plat/arm/board/juno/fdts/juno_fw_config.dts

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2020, ARM Limited. All rights reserved.
+ * Copyright (c) 2019-2021, ARM Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -17,5 +17,11 @@
 			max-size = <0x200>;
 			id = <TB_FW_CONFIG_ID>;
 		};
+
+		hw-config {
+			load-address = <0x0 0x82000000>;
+			max-size = <0x8000>;
+			id = <HW_CONFIG_ID>;
+		};
 	};
 };

plat/arm/board/juno/include/platform_def.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -53,6 +53,14 @@
 #define PLAT_ARM_DRAM2_BASE		ULL(0x880000000)
 #define PLAT_ARM_DRAM2_SIZE		ULL(0x180000000)
 
+#define PLAT_HW_CONFIG_DTB_BASE		ULL(0x82000000)
+#define PLAT_HW_CONFIG_DTB_SIZE		ULL(0x00008000) /* 32KB */
+
+#define ARM_DTB_DRAM_NS			MAP_REGION_FLAT(		\
+					PLAT_HW_CONFIG_DTB_BASE,	\
+					PLAT_HW_CONFIG_DTB_SIZE,	\
+					MT_MEMORY | MT_RO | MT_NS)
+
 /* virtual address used by dynamic mem_protect for chunk_base */
 #define PLAT_ARM_MEM_PROTEC_VA_FRAME	UL(0xc0000000)
 
@@ -108,7 +116,7 @@
 
 #ifdef IMAGE_BL31
 #  define PLAT_ARM_MMAP_ENTRIES		7
-#  define MAX_XLAT_TABLES		3
+#  define MAX_XLAT_TABLES		5
 #endif
 
 #ifdef IMAGE_BL32

plat/arm/board/juno/juno_bl2_setup.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017,2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -8,6 +8,9 @@
 
 #include <common/bl_common.h>
 #include <common/desc_image_load.h>
+#include <lib/fconf/fconf.h>
+#include <lib/fconf/fconf_dyn_cfg_getter.h>
+
 #include <plat/arm/common/plat_arm.h>
 
 #if JUNO_AARCH32_EL3_RUNTIME
@@ -30,4 +33,41 @@ int arm_bl2_plat_handle_post_image_load(unsigned int image_id)
 
 	return err;
 }
+
+#else
+
+/*******************************************************************************
+ * This function returns the list of executable images
+ ******************************************************************************/
+struct bl_params *plat_get_next_bl_params(void)
+{
+	struct bl_params *arm_bl_params = arm_get_next_bl_params();
+
+#if __aarch64__
+	const struct dyn_cfg_dtb_info_t *fw_config_info;
+	bl_mem_params_node_t *param_node;
+	uintptr_t fw_config_base = 0U;
+	entry_point_info_t *ep_info;
+
+	/* Get BL31 image node */
+	param_node = get_bl_mem_params_node(BL31_IMAGE_ID);
+	assert(param_node != NULL);
+
+	/* Get fw_config load address */
+	fw_config_info = FCONF_GET_PROPERTY(dyn_cfg, dtb, FW_CONFIG_ID);
+	assert(fw_config_info != NULL);
+
+	fw_config_base = fw_config_info->config_addr;
+	assert(fw_config_base != 0U);
+
+	/*
+	 * Get the entry point info of BL31 image and override
+	 * arg1 of entry point info with fw_config base address
+	 */
+	ep_info = &param_node->ep_info;
+	ep_info->args.arg1 = (uint32_t)fw_config_base;
+#endif /* __aarch64__ */
+
+	return arm_bl_params;
+}
 #endif /* JUNO_AARCH32_EL3_RUNTIME */

plat/arm/board/juno/juno_bl31_setup.c

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2021, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <common/debug.h>
+#include <lib/fconf/fconf.h>
+#include <lib/fconf/fconf_dyn_cfg_getter.h>
+
+#include <plat/arm/common/plat_arm.h>
+
+void __init bl31_early_platform_setup2(u_register_t arg0,
+		u_register_t arg1, u_register_t arg2, u_register_t arg3)
+{
+	const struct dyn_cfg_dtb_info_t *soc_fw_config_info;
+
+	INFO("BL31 FCONF: FW_CONFIG address = %lx\n", (uintptr_t)arg1);
+
+	/* Fill the properties struct with the info from the config dtb */
+	fconf_populate("FW_CONFIG", arg1);
+
+	soc_fw_config_info = FCONF_GET_PROPERTY(dyn_cfg, dtb, SOC_FW_CONFIG_ID);
+	if (soc_fw_config_info != NULL) {
+		arg1 = soc_fw_config_info->config_addr;
+	}
+
+	arm_bl31_early_platform_setup((void *)arg0, arg1, arg2, (void *)arg3);
+
+	/*
+	 * Initialize Interconnect for this cluster during cold boot.
+	 * No need for locks as no other CPU is active.
+	 */
+	plat_arm_interconnect_init();
+
+	/*
+	 * Enable Interconnect coherency for the primary CPU's cluster.
+	 * Earlier bootloader stages might already do this (e.g. Trusted
+	 * Firmware's BL1 does it) but we can't assume so. There is no harm in
+	 * executing this code twice anyway.
+	 * Platform specific PSCI code will enable coherency for other
+	 * clusters.
+	 */
+	plat_arm_interconnect_enter_coherency();
+}
+
+void __init bl31_plat_arch_setup(void)
+{
+	arm_bl31_plat_arch_setup();
+
+	/* HW_CONFIG was also loaded by BL2 */
+	const struct dyn_cfg_dtb_info_t *hw_config_info;
+
+	hw_config_info = FCONF_GET_PROPERTY(dyn_cfg, dtb, HW_CONFIG_ID);
+	assert(hw_config_info != NULL);
+
+	fconf_populate("HW_CONFIG", hw_config_info->config_addr);
+}

plat/arm/board/juno/juno_common.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -75,6 +75,7 @@ const mmap_region_t plat_arm_mmap[] = {
 	ARM_V2M_MAP_MEM_PROTECT,
 #endif
 	SOC_CSS_MAP_DEVICE,
+	ARM_DTB_DRAM_NS,
 	{0}
 };
 #endif

plat/arm/board/juno/platform.mk

@@ -83,6 +83,10 @@ BL31_SOURCES		+=	drivers/cfi/v2m/v2m_flash.c		\
 				lib/cpus/aarch64/cortex_a57.S		\
 				lib/cpus/aarch64/cortex_a72.S		\
 				lib/utils/mem_region.c			\
+				common/fdt_wrappers.c			\
+				lib/fconf/fconf.c			\
+				lib/fconf/fconf_dyn_cfg_getter.c	\
+				plat/arm/board/juno/juno_bl31_setup.c	\
 				plat/arm/board/juno/juno_pm.c		\
 				plat/arm/board/juno/juno_topology.c	\
 				plat/arm/common/arm_nor_psci_mem_protect.c \
@@ -174,15 +178,19 @@ BL32_CPPFLAGS += -march=armv8-a+crc
 
 # Add the FDT_SOURCES and options for Dynamic Config
 FDT_SOURCES		+=	plat/arm/board/juno/fdts/${PLAT}_fw_config.dts	\
-				plat/arm/board/juno/fdts/${PLAT}_tb_fw_config.dts
+				plat/arm/board/juno/fdts/${PLAT}_tb_fw_config.dts \
+				fdts/${PLAT}.dts
 
 FW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}_fw_config.dtb
 TB_FW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}_tb_fw_config.dtb
+HW_CONFIG		:=	${BUILD_PLAT}/fdts/${PLAT}.dtb
 
 # Add the FW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${FW_CONFIG},--fw-config,${FW_CONFIG}))
 # Add the TB_FW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${TB_FW_CONFIG},--tb-fw-config,${TB_FW_CONFIG}))
+# Add the HW_CONFIG to FIP and specify the same to certtool
+$(eval $(call TOOL_ADD_PAYLOAD,${HW_CONFIG},--hw-config,${HW_CONFIG}))
 
 include plat/arm/board/common/board_common.mk
 include plat/arm/common/arm_common.mk