当前位置： 文江博客话题详情

U-Boot：如何从SD卡加载U-Boot，但是是否从QSPI Flash加载环境？

发布于 2025-02-11 06:43:16 字数 4025 浏览 0 评论 0原文

我很难配置U-Boot，特别是将其设置为可以从SD卡加载，但是可以从QSPI Flash访问其环境。

首先，这甚至可能吗？可以将U-Boot环境存储在与加载U-Boot的不同位置吗？

当前，我在Xilinx MPSOC ARM64平台上从QSPI Flash运行了U-Boot映像。我正在使用xilinx 但是，petalinux我想我了解这种配置的U-Boot是如何在“引擎盖下”配置的，所以我会尝试参考 尽我所能。

默认值之外

#define CONFIG_ENV_OFFSET 0x2E00000
#define CONFIG_ENV_OVERWRITE 1
#define CONFIG_CMD_ERASEENV 1

除了所有 QSPI闪存和SD卡模式之间的可信固件）。该平台还需要一个所谓的“ boot.bin”， 是U-Boot二进制，Xilinx FSBL，ARM Trust固件，FPGA图像的聚合 其他事情，要写给我已经做过的QSPI Flash。这一切都可以正常工作，并且串行控制台 在重置或电源上看起来像这样：

Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
NOTICE:  BL31: v2.4(release):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021


U-Boot 2021.01 (Oct 12 2021 - 09:28:42 +0000)

CPU:   ZynqMP
Silicon: v3
Model: ZynqMP ZCU208 RevA
Board: Xilinx ZynqMP
DRAM:  4 GiB
PMUFW:  v1.1
EL Level:       EL2
Chip ID:        zu48dr
NAND:  0 MiB
MMC:   mmc@ff170000: 0
Loading Environment from SPIFlash... SF: Detected mt25qu02g with page size 512 Bytes, erase size 128 KiB, total 512 MiB
...

如您所见，QSPI Flash的U-Boot负载也从QSPI Flash中加载。一切都很好。

我想做的就是修改系统，以便第一阶段引导加载程序从SD卡加载U-Boot。在我的配置中 已经具有config_env_is_in_fat <​​/code>设置为1。 平台的启动模式通过物理开关到“ SD卡”，单元成功地从SD卡加载U-boot，并且 串行控制台显示与上述类似的输出，但与以下方式相似

Loading Environment from FAT... *** Warning - bad CRC, using default environment

，尽管预期此警告是因为SD卡上还没有保留环境。 它确实表明SD卡正在检查环境，所以很好。

请注意，这是我较早用于QSPI Flash启动的同一构建，但它正在寻找fat上的配置，因此我目前的印象是 U-Boot仅根据启用其他位置的位置来寻找其环境。我还尝试了Qemu，似乎认为配置来自“无处”，但这可能会分散注意力。

问题是我想配置从SD卡加载的U-Boot（以便于升级 /开发），但要将QSPI用于其环境， 这样我就可以在板本身上存储持久的u-boot配置。

尤其是 ，板上的MAC地址是不可读取的，因此必须在U-Boot中手动配置，而我' d那样跟随董事会，而不是SD卡。我还想设置其他一些选项。

根据我已阅读的U-Boot文档，将脂肪禁用为默认值应通过不设置来实现 按照u-boot.cfg：

CONFIG_ENV_IS_IN_FAT
CONFIG_SYS_MMC_ENV_DEV
CONFIG_ENV_FAT_DEVICE_AND_PART
CONFIG_ENV_IS_IN_FAT
CONFIG_ENV_FAT_FILE
CONFIG_SYS_MMC_ENV_PART
CONFIG_ENV_FAT_INTERFACE

执行与上述相同的安装步骤，以使此新的U-Boot从SD卡中加载，从而导致 以下输出：

Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
NOTICE:  BL31: v2.4(release):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021

就是这样！不再输出。板上有一个从红色到绿色的LED，我认为这表明 boot.bin中的FPGA图像已成功地加载到门数阵列中，所以我认为较早的引导加载程序 已找到boot.bin。因此，我没有理由认为u-boot尚未加载，但是如果有的话，那是 没有产生输出。我尝试将U-Boot的调试水平提高到7（调试），以期看到一些东西 来自U-Boot，但这没什么区别。它也不是启动Linux，通常会发生下一步。

任何人都可以阐明为什么进行这种更改可能会导致这种行为？还有其他吗 配置选项我需要设置以确保当config_env_is_in_fat <​​/code>时，U-Boot可以从SD卡运行。 和朋友没有设定？也许我可以保留config_env_is_in_fat <​​/code>等 u-boot即使从SD卡中加载了QSPI闪光灯？

注意：我还启用了ATF调试，该调试会产生以下输出，但它仍然挂着没有U-Boot的迹象：

INFO:    PSCI Power Domain Map:
INFO:      Domain Node : Level 1, parent_node -1, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x0, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x1, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x2, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x3, parent_node 0, State ON (0x0)
Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
WARNING: BL31: invalid exception level (3)
NOTICE:  BL31: v2.4(debug):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021
INFO:    ARM GICv2 driver initialized
INFO:    BL31: Initializing runtime services
INFO:    BL31: PM Service Init Complete: API v1.1
INFO:    BL31: cortex_a53: CPU workaround for 855873 was applied
WARNING: BL31: cortex_a53: CPU workaround for 1530924 was missing!
INFO:    BL31: Preparing for EL3 exit to normal world
INFO:    Entry point address = 0x8000000
INFO:    SPSR = 0x3c9
原文

I'm having some difficulty configuring U-Boot, in particular setting it up so that it can load from an SD card, but access its Environment from QSPI Flash.

First of all, is this even possible? Can the U-Boot environment be stored in a different location from where U-Boot was loaded?

Currently, I have a U-Boot image running from QSPI Flash on a Xilinx MPSoC ARM64 platform. I'm using Xilinx
PetaLinux however I think I understand how this configures U-Boot "under the hood" so I'll try to refer to
uboot.cfg​ as much as I can.

Along with all the defaults, I have set:

#define CONFIG_ENV_OFFSET 0x2E00000
#define CONFIG_ENV_OVERWRITE 1
#define CONFIG_CMD_ERASEENV 1

On this particular platform, there is a physical switch to switch the Xilinx first-stage bootloader (and ARM
Trusted Firmware) between QSPI Flash and SD card modes. This platform also requires a so-called "BOOT.BIN", which
is an aggregation of the u-boot binary, the Xilinx FSBL, ARM Trusted Firmware, an FPGA image and
other things, to be written to QSPI Flash, which I have done. This is all working correctly, and the serial console
looks like this at reset or power-on:

Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
NOTICE:  BL31: v2.4(release):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021


U-Boot 2021.01 (Oct 12 2021 - 09:28:42 +0000)

CPU:   ZynqMP
Silicon: v3
Model: ZynqMP ZCU208 RevA
Board: Xilinx ZynqMP
DRAM:  4 GiB
PMUFW:  v1.1
EL Level:       EL2
Chip ID:        zu48dr
NAND:  0 MiB
MMC:   mmc@ff170000: 0
Loading Environment from SPIFlash... SF: Detected mt25qu02g with page size 512 Bytes, erase size 128 KiB, total 512 MiB
...

As you can see, U-Boot loads from QSPI Flash and the Environment is also loaded from QSPI Flash. All good.

What I want to do is modify the system so that the First Stage Boot Loader loads U-Boot from the SD card. In my config I
already have CONFIG_ENV_IS_IN_FAT set to 1. When I copy BOOT.BIN to the first, FAT partition on an SD card, and set my
platform's boot mode to "SD Card" via the physical switch, the unit loads U-Boot from the SD card successfully, and the
serial console shows output similar to the above but with:

Loading Environment from FAT... *** Warning - bad CRC, using default environment

It works, although this warning is expected because there is no Environment saved on the SD card yet.
It does show that the SD card is being checked for the Environment though, so that's good.

Note that this is the same build that I used for the QSPI flash boot earlier, but it's looking for the config on FAT, so I'm currently under the impression that
U-Boot only looks for its Environment based on where it was loaded from, even if other locations are enabled. I also tried in QEMU and it seemed to think that the config came from "nowhere", but that may be a distraction.

The issue is that I would like to configure U-Boot to be loaded from the SD card (for ease of upgrade / development), but to use QSPI for its Environment,
so that I can store persistent U-Boot configuration on the board itself.

In particular, the MAC address for the board is not readable via software so must be manually configured in U-Boot, and I'd like that to follow around the board, not the SD card. There are a few other options I'd like to set per-board also.

According to the U-Boot documentation I've read, disabling FAT as the default should be achievable by unsetting the
following in u-boot.cfg:

CONFIG_ENV_IS_IN_FAT
CONFIG_SYS_MMC_ENV_DEV
CONFIG_ENV_FAT_DEVICE_AND_PART
CONFIG_ENV_IS_IN_FAT
CONFIG_ENV_FAT_FILE
CONFIG_SYS_MMC_ENV_PART
CONFIG_ENV_FAT_INTERFACE

Performing the same installation steps as above, to have this new U-Boot loaded from the SD card, results in the
following output:

Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
NOTICE:  BL31: v2.4(release):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021

And that's it! No more output. There is an LED on the board that goes from red to green, which I think indicates that
the FPGA image within BOOT.BIN has been loaded into the gate array successfully, so I think the earlier boot loader
has found BOOT.BIN. I have no reason therefore to think that U-Boot has not also been loaded, but if it has, it is
generating no output. I tried increasing the debug level of U-Boot to 7 (DEBUG) in the hope of seeing something
from U-Boot, but that makes no difference. It's also not booting Linux, which would normally happen next.

Can anyone shed any light on why making this change might result in this behaviour? Is there some other
configuration option I need to set to ensure that U-Boot can run from the SD card when CONFIG_ENV_IS_IN_FAT
and friends are not set? Or perhaps I can keep CONFIG_ENV_IS_IN_FAT etc. and there's some other way to instruct
U-Boot to use the QSPI Flash for its environment, even though it was loaded from SD card?

Note: I've also enabled ATF debugging, which produces the following output, but it still hangs with no sign of U-Boot:

INFO:    PSCI Power Domain Map:
INFO:      Domain Node : Level 1, parent_node -1, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      Domain Node : Level 0, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x0, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x1, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x2, parent_node 0, State ON (0x0)
INFO:      CPU Node : MPID 0x3, parent_node 0, State ON (0x0)
Xilinx Zynq MP First Stage Boot Loader
Release 2021.2   Oct 13 2021  -  07:15:53
WARNING: BL31: invalid exception level (3)
NOTICE:  BL31: v2.4(debug):xlnx_rebase_v2.4_2021.1_update1-23-g9188496b9
NOTICE:  BL31: Built : 07:41:24, Oct 13 2021
INFO:    ARM GICv2 driver initialized
INFO:    BL31: Initializing runtime services
INFO:    BL31: PM Service Init Complete: API v1.1
INFO:    BL31: cortex_a53: CPU workaround for 855873 was applied
WARNING: BL31: cortex_a53: CPU workaround for 1530924 was missing!
INFO:    BL31: Preparing for EL3 exit to normal world
INFO:    Entry point address = 0x8000000
INFO:    SPSR = 0x3c9

如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论， 你可以免费 注册 一个本站的账号。

评论（1）

煮酒 2025-02-18 06:43:16

回答我自己的问题：

在这种情况下，我不知道控制台为什么保持空白/死亡，但是相关的代码在这里：

https://github.com/u-boot/u-boot/u-boot/u-boot/boot/boot/boot/blob/master/board/board/xilinx/zynqmp/zynqmp/zynqmp-. .c＃l850

根据此switch语句，当启动模式为sd_mode时，情况不考虑config_env_is_in_in_spi_flash ，因此该功能返回envl_nowhere使用config_env_is_in_fat <​​/code> disabled从SD启动时。

修改此函数以返回envl_spi_flash在这种情况下，启用u-boot访问qspi flash中的环境：

    case SD_MODE1:
        if (IS_ENABLED(CONFIG_ENV_IS_IN_FAT))
            return ENVL_FAT;
        if (IS_ENABLED(CONFIG_ENV_IS_IN_EXT4))
            return ENVL_EXT4;
++      if (IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH))
++          return ENVL_SPI_FLASH;
        return ENVL_NOWHERE;

Answering my own question:

I do not know why the console remains blank/dead in this case, but the related code is this function here:

https://github.com/u-boot/u-boot/blob/master/board/xilinx/zynqmp/zynqmp.c#L850

According to this switch statement, when the boot mode is SD_MODE, the case does not consider CONFIG_ENV_IS_IN_SPI_FLASH at all, and therefore the function returns ENVL_NOWHERE when booted from SD with CONFIG_ENV_IS_IN_FAT disabled.

Modifying this function to return ENVL_SPI_FLASH in this case enables U-Boot access to the Environment in the QSPI Flash:

    case SD_MODE1:
        if (IS_ENABLED(CONFIG_ENV_IS_IN_FAT))
            return ENVL_FAT;
        if (IS_ENABLED(CONFIG_ENV_IS_IN_EXT4))
            return ENVL_EXT4;
++      if (IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH))
++          return ENVL_SPI_FLASH;
        return ENVL_NOWHERE;
回复 原文
~没有更多了~

关于作者

紫南

暂无简介

文章
评论
27 人气
发私信

相关话题

更多

热门标签

操作系统 程序设计 IT运维 Linux系统管理 JavaScript 服务器应用 solaris C/C++ PHP Shell BSD Vue.js aix Oracle Python HTML 系统管理 HTML5 CSS 前端
更多

推荐作者

夢野间

文章 0 评论 0

百度③文鱼

文章 0 评论 0

小草泠泠

文章 0 评论 0

zhuwenyan

文章 0 评论 0

weirdo

文章 0 评论 0

坚持沉默

文章 0 评论 0

更多

友情链接

文江博客
    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站，即表示您同意使用 Cookies 和您的相关数据。
    原文