u-boot-brain/arch/arm/mach-stm32mp/boot_params.c
Patrick Delaunay 4ac345220a board: stm32mp1: use FDT address provided by TF-A at boot time
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>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
2020-05-14 09:02:12 +02:00

46 lines
1.1 KiB
C

// 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;
}