mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-07-11 21:56:21 +09:00
2a5f7f2074
On Tegra186, U-Boot is booted by the binary firmware as if it were a Linux kernel. Consequently, a DTB is passed to U-Boot. Cache the address of that DTB, and parse the /memory/reg property to determine the actual RAM regions that U-Boot and subsequent EL2/EL1 SW may actually use. Given the binary FW passes a DTB to U-Boot, I anticipate the suggestion that U-Boot use that DTB as its control DTB. I don't believe that would work well, so I do not plan to put any effort into this. By default the FW-supplied DTB is the L4T kernel's DTB, which uses non-upstreamed DT bindings. U-Boot aims to use only upstreamed DT bindings, or as close as it can get. Replacing this DTB with a DTB using upstream bindings is physically quite easy; simply replace the content of one of the GPT partitions on the eMMC. However, the binary FW at least partially relies on the existence/content of some nodes in the DTB, and that requires the DTB to be written according to downstream bindings. Equally, if U-Boot continues to use appended DTBs built from its own source tree, as it does for all other Tegra platforms, development and deployment is much easier. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Tom Warren <twarren@nvidia.com>
21 lines
370 B
ArmAsm
21 lines
370 B
ArmAsm
/*
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* Save nvtboot-related boot-time CPU state
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*
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* (C) Copyright 2015-2016 NVIDIA Corporation <www.nvidia.com>
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <config.h>
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#include <linux/linkage.h>
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.globl nvtboot_boot_x0
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nvtboot_boot_x0:
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.dword 0
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ENTRY(save_boot_params)
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adr x8, nvtboot_boot_x0
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str x0, [x8]
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b save_boot_params_ret
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ENDPROC(save_boot_params)
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