Save and use the FDT address provided by TF-A in r2 at boot time (it is NT_FW_CONFIG = Non Trusted Firmware configuration file)
Address is saved in save_boot_params(), called by start.S and the used DTB is gd->fdt_blob = board_fdt_blob_setup().
If dtb is not provided or invalid, U-Boot use as fallback the builtin DTB.
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
arch/arm/mach-stm32mp/Makefile | 1 + arch/arm/mach-stm32mp/boot_params.c | 45 +++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+) create mode 100644 arch/arm/mach-stm32mp/boot_params.c
diff --git a/arch/arm/mach-stm32mp/Makefile b/arch/arm/mach-stm32mp/Makefile index eee39c27c3..19ca3b08a5 100644 --- a/arch/arm/mach-stm32mp/Makefile +++ b/arch/arm/mach-stm32mp/Makefile @@ -13,6 +13,7 @@ else obj-y += bsec.o obj-$(CONFIG_CMD_STM32KEY) += cmd_stm32key.o obj-$(CONFIG_ARMV7_PSCI) += psci.o +obj-$(CONFIG_STM32MP1_TRUSTED) += boot_params.o endif
obj-$(CONFIG_$(SPL_)DM_REGULATOR) += pwr_regulator.o diff --git a/arch/arm/mach-stm32mp/boot_params.c b/arch/arm/mach-stm32mp/boot_params.c new file mode 100644 index 0000000000..e4351de939 --- /dev/null +++ b/arch/arm/mach-stm32mp/boot_params.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause +/* + * Copyright (C) 2019, STMicroelectronics - All Rights Reserved + */ + +#include <common.h> +#include <asm/sections.h> +#include <asm/system.h> + +/* + * Force data-section, as .bss will not be valid + * when save_boot_params is invoked. + */ +static unsigned long nt_fw_dtb __section(".data"); + +/* + * Save the FDT address provided by TF-A in r2 at boot time + * This function is called from start.S + */ +void save_boot_params(unsigned long r0, unsigned long r1, unsigned long r2, + unsigned long r3) +{ + nt_fw_dtb = r2; + + save_boot_params_ret(); +} + +/* + * Use the saved FDT address provided by TF-A at boot time (NT_FW_CONFIG = + * Non Trusted Firmware configuration file) when the pointer is valid + */ +void *board_fdt_blob_setup(void) +{ + debug("%s: nt_fw_dtb=%lx\n", __func__, nt_fw_dtb); + + /* use external device tree only if address is valid */ + if (nt_fw_dtb >= STM32_DDR_BASE) { + if (fdt_magic(nt_fw_dtb) == FDT_MAGIC) + return (void *)nt_fw_dtb; + debug("%s: DTB not found.\n", __func__); + } + debug("%s: fall back to builtin DTB, %p\n", __func__, &_end); + + return (void *)&_end; +}