config TARGET_DRAGONBOARD410C
bool "96Boards Dragonboard 410C"
select BOARD_LATE_INIT
+ select ENABLE_ARM_SOC_BOOT0_HOOK
help
Support for 96Boards Dragonboard 410C. This board complies with
96Board Open Platform Specifications. Features:
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Workaround for "PSCI bug" on DragonBoard 410c
+ * Copyright (C) 2021 Stephan Gerhold <stephan@gerhold.net>
+ *
+ * Syscall parameters taken from Qualcomm's LK fork (scm.h):
+ * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
+ *
+ * The PSCI implementation in the TrustZone/tz firmware on DragonBoard 410c has
+ * a bug that starts all other CPU cores in 32-bit mode unless the TZ syscall
+ * that switches from 32-bit to 64-bit mode is executed at least once.
+ *
+ * Normally this happens inside Qualcomm's LK bootloader which runs in 32-bit
+ * mode and uses the TZ syscall to boot a kernel in 64-bit mode. However, if
+ * U-Boot is installed to the "aboot" partition (replacing LK) the switch to
+ * 64-bit mode never happens since U-Boot is already running in 64-bit mode.
+ *
+ * A workaround for this "PSCI bug" is to execute the TZ syscall when entering
+ * U-Boot. That way PSCI is made aware of the 64-bit switch and starts all other
+ * CPU cores in 64-bit mode as well.
+ */
+#include <linux/arm-smccc.h>
+
+#define ARM_SMCCC_SIP32_FAST_CALL \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, ARM_SMCCC_OWNER_SIP, 0)
+
+ /*
+ * U-Boot might be started in EL2 or EL3 with custom firmware.
+ * In that case, we assume that the workaround is not necessary or is
+ * handled already by the alternative firmware. Using the syscall in EL2
+ * would demote U-Boot to EL1; in EL3 it would probably just crash.
+ */
+ mrs x0, CurrentEL
+ cmp x0, #(1 << 2) /* EL1 */
+ bne reset
+
+ /* Prepare TZ syscall parameters */
+ mov x0, #ARM_SMCCC_SIP32_FAST_CALL
+ movk x0, #0x10f /* SCM_SVC_MILESTONE_CMD_ID */
+ mov x1, #0x12 /* MAKE_SCM_ARGS(0x2, SMC_PARAM_TYPE_BUFFER_READ) */
+ adr x2, el1_system_param
+ mov x3, el1_system_param_end - el1_system_param
+
+ /* Switch PSCI to 64-bit mode. Resets CPU and returns at el1_elr */
+ smc #0
+
+ /* Something went wrong, perhaps PSCI is already in 64-bit mode? */
+ b reset
+
+ .align 3
+el1_system_param:
+ .quad 0, 0, 0, 0, 0, 0, 0, 0, 0 /* el1_x0-x8 */
+ .quad reset /* el1_elr */
+el1_system_param_end:
F: board/qualcomm/dragonboard410c/
F: include/configs/dragonboard410c.h
F: configs/dragonboard410c_defconfig
+F: doc/board/qualcomm/dragonboard410c.rst
# (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
obj-y := dragonboard410c.o
-obj-y += lowlevel_init.o
-extra-y += head.o
DECLARE_GLOBAL_DATA_PTR;
-/* pointer to the device tree ammended by the firmware */
-extern void *fw_dtb;
-
-void *board_fdt_blob_setup(void)
-{
- if (fdt_magic(fw_dtb) != FDT_MAGIC) {
- printf("Firmware provided invalid dtb!\n");
- return NULL;
- }
-
- return fw_dtb;
-}
-
int dram_init(void)
{
gd->ram_size = PHYS_SDRAM_1_SIZE;
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0+ */
-/*
- * ARM64 header for proper chain-loading with Little Kernel.
- *
- * Little Kernel shipped with Dragonboard410C boots standard Linux images for
- * ARM64. This file adds header that is required to boot U-Boot properly.
- *
- * For details see:
- * https://www.kernel.org/doc/Documentation/arm64/booting.txt
- *
- * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
- */
-
-#include <config.h>
-
-.global _arm64_header
-_arm64_header:
- b _start
- .word 0
- /* Image load offset from start of RAM, little-endian */
- .quad CONFIG_SYS_TEXT_BASE-PHYS_SDRAM_1
- /* Effective size of kernel image, little-endian */
- .quad 0 /* 0x60000 - ignored */
- /* Informative flags, little-endian */
- .quad 0
- .quad 0 /* reserved */
- .quad 0 /* reserved */
- .quad 0 /* reserved */
- .byte 0x41 /* Magic number, "ARM\x64" */
- .byte 0x52
- .byte 0x4d
- .byte 0x64
- .word 0 /* reserved */
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0+ */
-/*
- * (C) Copyright 2016
- * Cédric Schieli <cschieli@gmail.com>
- */
-
-#include <config.h>
-
-.align 8
-.global fw_dtb
-fw_dtb:
- .dword 0x0
-
-/*
- * Routine: save_boot_params (called after reset from start.S)
- * Description: save ATAG/FDT address provided by the firmware at boot time
- */
-
-.global save_boot_params
-save_boot_params:
-
- /* The firmware provided ATAG/FDT address can be found in r2/x0 */
- adr x8, fw_dtb
- str x0, [x8]
-
- /* Returns */
- b save_boot_params_ret
-# SPDX-License-Identifier: GPL-2.0+
-#
-# (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+Documentation for DragonBoard 410c is now located at:
+ doc/board/qualcomm/dragonboard410c.rst
-Build & Run instructions:
-
-1) Install mkbootimg and dtbTool from
- git://codeaurora.org/quic/kernel/skales (15ece94f09 worked for me)
-2) Setup CROSS_COMPILE to aarch64 compiler
-3) make dragonboard410c_config
-4) make
-5) generate fake, empty ramdisk (can have 0 bytes)
-$ touch rd
-
-6) Generate qualcomm device tree table with dtbTool [1]
-$ dtbTool -o dt.img arch/arm/dts
-
-7) Generate Android boot image with mkbootimg [2]:
-$ mkbootimg --kernel=u-boot-dtb.bin --output=u-boot.img --dt=dt.img \
- --pagesize 2048 --base 0x80000000 --ramdisk=rd --cmdline=""
-
-8) Enter fastboot (reboot board with vol- button pressed)
-
-9) Boot it:
-$ fastboot boot u-boot.img
-or flash as kernel:
-$ fastboot flash boot u-boot.img
-$ fastboot reboot
-
-
-What is working:
-- UART
-- GPIO (SoC)
-- SD
-- eMMC
-- Reset
-- USB in EHCI mode (usb starts does switch device->host, usb stop does the opposite)
-- PMIC GPIOS (but not in generic subsystem)
-- PMIC "special" buttons (power, vol-)
-
-What is not working / known bugs:
-- SDHCI is slow (~2.5MiB/s for SD and eMMC)
-
-[1] To boot any kernel image, Little Kernel requires valid device tree for the
-platform it runs on. dtbTool creates device tree table that Little Kernel scans.
-Later on proper device tree is passed to next boot stage.
-Full device tree is not required to boot u-boot. Enough would be:
-/dts-v1/;
-
-/ {
- model = "Qualcomm Technologies, Inc. Dragonboard 410c";
- compatible = "qcom,dragonboard", "qcom,apq8016-sbc";
- qcom,msm-id = <0xce 0x0 0xf8 0x0 0xf9 0x0 0xfa 0x0 0xf7 0x0>;
- qcom,board-id = <0x10018 0x0>;
- #address-cells = <0x2>;
- #size-cells = <0x2>;
- chosen { };
- aliases { };
-
- memory {
- device_type = "memory";
- reg = <0 0x80000000 0 0x3da00000>;
- };
-};
-
-but for simplicity (and because size of image is not that critical) we use
-existing Qualcomm device trees.
-
-[2] Note that ramdisk is required, even if it is unused.
+Note that the installation method has changed: U-Boot is now installed into the
+"aboot" partition (replacing Little Kernel/LK). It is no longer packaged into
+an Android boot image and loaded through Qualcomm's LK bootloader.
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0+ */
-/*
- * Override linker script for fastboot-readable images
- *
- * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
- *
- * Based on arch/arm/cpu/armv8/u-boot.lds (Just add header)
- */
-
-OUTPUT_FORMAT("elf64-littleaarch64", "elf64-littleaarch64", "elf64-littleaarch64")
-OUTPUT_ARCH(aarch64)
-ENTRY(_arm64_header)
-SECTIONS
-{
- . = 0x00000000;
-
- . = ALIGN(8);
- .text :
- {
- *(.__image_copy_start)
- board/qualcomm/dragonboard410c/head.o (.text*)
- CPUDIR/start.o (.text*)
- }
-
- /* This needs to come before *(.text*) */
- .efi_runtime : {
- __efi_runtime_start = .;
- *(.text.efi_runtime*)
- *(.rodata.efi_runtime*)
- *(.data.efi_runtime*)
- __efi_runtime_stop = .;
- }
-
- .text_rest :
- {
- *(.text*)
- }
-
- . = ALIGN(8);
- .rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }
-
- . = ALIGN(8);
- .data : {
- *(.data*)
- }
-
- . = ALIGN(8);
-
- . = .;
-
- . = ALIGN(8);
- .u_boot_list : {
- KEEP(*(SORT(.u_boot_list*)));
- }
-
- . = ALIGN(8);
-
- .efi_runtime : {
- __efi_runtime_start = .;
- *(efi_runtime_text)
- *(efi_runtime_data)
- __efi_runtime_stop = .;
- }
-
- .efi_runtime_rel : {
- __efi_runtime_rel_start = .;
- *(.rel*.efi_runtime)
- *(.rel*.efi_runtime.*)
- __efi_runtime_rel_stop = .;
- }
-
- . = ALIGN(8);
-
- .image_copy_end :
- {
- *(.__image_copy_end)
- }
-
- . = ALIGN(8);
-
- .rel_dyn_start :
- {
- *(.__rel_dyn_start)
- }
-
- .rela.dyn : {
- *(.rela*)
- }
-
- .rel_dyn_end :
- {
- *(.__rel_dyn_end)
- }
-
- _end = .;
-
- . = ALIGN(8);
-
- .bss_start : {
- KEEP(*(.__bss_start));
- }
-
- .bss : {
- *(.bss*)
- . = ALIGN(8);
- }
-
- .bss_end : {
- KEEP(*(.__bss_end));
- }
-
- /DISCARD/ : { *(.dynsym) }
- /DISCARD/ : { *(.dynstr*) }
- /DISCARD/ : { *(.dynamic*) }
- /DISCARD/ : { *(.plt*) }
- /DISCARD/ : { *(.interp*) }
- /DISCARD/ : { *(.gnu*) }
-}
CONFIG_ARM=y
CONFIG_ARCH_SNAPDRAGON=y
-CONFIG_SYS_TEXT_BASE=0x80080000
+CONFIG_SYS_TEXT_BASE=0x8f600000
CONFIG_NR_DRAM_BANKS=1
CONFIG_ENV_SIZE=0x2000
CONFIG_ENV_OFFSET=0x0
kontron/index
microchip/index
openpiton/index
+ qualcomm/index
rockchip/index
sifive/index
sipeed/index
--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0+
+.. sectionauthor:: Stephan Gerhold <stephan@gerhold.net>
+
+DragonBoard 410c
+================
+
+The DragonBoard 410c is a development board based on the Qualcomm APQ8016E SoC.
+More information can be found on the `96Boards product page`_.
+
+U-Boot can be used as a replacement for Qualcomm's original Android bootloader
+(a fork of Little Kernel/LK). Like LK, it is installed directly into the ``aboot``
+partition. Note that the U-Boot port used to be loaded as an Android boot image
+through LK. This is no longer the case, now U-Boot can replace LK entirely.
+
+.. _96Boards product page: https://www.96boards.org/product/dragonboard410c/
+
+Installation
+------------
+First, setup ``CROSS_COMPILE`` for aarch64. Then, build U-Boot for ``dragonboard410c``::
+
+ $ export CROSS_COMPILE=<aarch64 toolchain prefix>
+ $ make dragonboard410c_defconfig
+ $ make
+
+This will build ``u-boot.elf`` in the configured output directory.
+
+Although the DragonBoard 410c does not have secure boot set up by default,
+the firmware still expects firmware ELF images to be "signed". The signature
+does not provide any security in this case, but it provides the firmware with
+some required metadata.
+
+To "sign" ``u-boot.elf`` you can use e.g. `qtestsign`_::
+
+ $ ./qtestsign.py aboot u-boot.elf
+
+Then install the resulting ``u-boot-test-signed.mbn`` to the ``aboot`` partition
+on your device, e.g. with ``fastboot flash aboot u-boot-test-signed.mbn``.
+
+U-Boot should be running after a reboot (``fastboot reboot``).
+
+.. _qtestsign: https://github.com/msm8916-mainline/qtestsign
+
+Usage
+-----
+Press Volume Down during boot to enter Fastboot mode.
--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0+
+
+Qualcomm
+========
+
+.. toctree::
+ :maxdepth: 2
+
+ dragonboard410c
#include <linux/sizes.h>
#include <asm/arch/sysmap-apq8016.h>
+/* Build new ELF image from u-boot.bin (U-Boot + appended DTB) */
+#define CONFIG_REMAKE_ELF
+
/* Physical Memory Map */
#define PHYS_SDRAM_1 0x80000000
/* 1008 MB (the last ~30Mb are secured for TrustZone by ATF*/