怎样通过uboot去修改sdc的频率以及以太网的delay参数呢

有时候经常需要临时调整部份设备树的属性配置，例如sdc的频率，以太网的delay参数。如果每次都源码修改后编译烧写，比较费时，所以uboot提供了临时修改的方法。
注：uboot修改都是单次启动有效，重启无效。
=> fdt print /soc/sdmmc@4021000
sdmmc@4021000 {
      compatible = "allwinner,sunxi-mmc-v5p3x";
      device_type = "sdc1";
      reg = <0x00000000 0x04021000 0x00000000 0x00001000>;
      interrupts = <0x00000000 0x00000029 0x00000004>;
      clocks = <0x0000000c 0x00000002 0x00000005 0x00000002 0x0000003a 0x00000002 0x0000003d>;
      clock-names = "osc24m", "pll_periph", "mmc", "ahb";
      resets = <0x00000002 0x00000010>;
      reset-names = "rst";
      pinctrl-names = "default", "sleep";
      pinctrl-0 = <0x00000022>;
      pinctrl-1 = <0x00000023>;
      max-frequency = <0x08f0d180>;
      bus-width = <0x00000004>;
      cap-sd-highspeed;
      no-mmc;
      keep-power-in-suspend;
      sunxi-dly-52M-ddr4 = <0x00000001 0x00000000 0x00000000 0x00000000 0x00000002>;
      sunxi-dly-104M = <0x00000001 0x00000000 0x00000000 0x00000000 0x00000001>;
      sunxi-dly-208M = <0x00000001 0x00000000 0x00000000 0x00000000 0x00000001>;
      status = "okay";
      no-sd;
      cap-sdio-irq;
      ignore-pm-notify;
      ctl-spec-caps = <0x00000008>;
};
修改sdc的最大支持频率
25M
fdt set /soc/sdmmc@04021000 max-frequency <0x017d7840>
50M
fdt set /soc/sdmmc@04021000 max-frequency <0x02faf080>
100M
fdt set /soc/sdmmc@04021000 max-frequency <0x05f5e100>
120M
fdt set /soc/sdmmc@04021000 max-frequency <0x07270e00>
150M
fdt set /soc/sdmmc@04021000 max-frequency <0x08f0d180>
修改相位
fdt set /soc/sdmmc@04021000 sunxi-dly-208M <0x00000001 0x00000000 0x00000000 0x00000000 0x00000000 0x00000001>
2.修改以太网的属性
打印当前以太网的配置
=> fdt print /soc/eth@4500000
eth@4500000 {
compatible = "allwinner,sunxi-gmac";
reg = <0x00000000 0x04500000 0x00000000 0x00010000 0x00000000 0x03000030 0x00000000 0x00000004>;
interrupts = <0x00000000 0x0000002e 0x00000004>;
interrupt-names = "gmacirq";
clocks = <0x00000002 0x00000050 0x00000002 0x0000004f>;
clock-names = "gmac", "ephy";
resets = <0x00000002 0x00000020>;
device_type = "gmac0";
gmac-power0;
gmac-power1;
gmac-power2;
status = "okay";
phy-mode = "rgmii";
use_ephy25m = <0x00000001>;
pinctrl-0 = <0x00000019>;
pinctrl-1 = <0x0000001a>;
pinctrl-names = "default", "sleep";
tx-delay = <0x00000003>;
rx-delay = <0x00000005>;
};

修改delay 参数
fdt set /soc/eth@4500000 rx-delay <0x0000000a>
：这里只是简单介绍uboot的命令，具体设备属性的解释就不展开说明了。

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李代三

2021-12-29 11:10:33

解决办法
uboot常用命令
fdt

=> fdt -h
fdt - flattened device tree utility commands

Usage:
fdt addr [-c]   [] - Set the [control] fdt location to
fdt apply                   - Apply overlay to the DT
fdt boardsetup                   - Do board-specific set up
fdt move - Copy the fdt to and make it active
fdt resize []          - Resize fdt to size + padding to 4k addr + some optional if needed
fdt print   []       - Recursive print starting at
fdt list []       - Print one level starting at
fdt get value - Get and store in fdt get name - Get name of node and store in fdt get addr - Get start address of and store in fdt get size []  - Get size of [] or num nodes and store in fdt set [] - Set [to ] fdt mknode          - Create a new node after fdt rm     []       - Delete the node or fdt header                         - Display header info fdt bootcpu                   - Set boot cpuid fdt memory          - Add/Update memory node fdt rsvmem print                   - Show current mem reserves fdt rsvmem add       - Add a mem reserve fdt rsvmem delete          - Delete a mem reserves fdt chosen [ ]       - Add/update the /chosen branch in the tree                                     / - initrd start/end addr printenv:打印环境变量 setenv:设置环境变量 saveenv:保存设置的环境变量 md:显示内存区的内容 mm:修改内存 cmp:比较两块内存解决办法 uboot常用命令 fdt => fdt -h fdt - flattened device tree utility commands Usage: fdt addr [-c]   [] - Set the [control] fdt location to fdt apply                   - Apply overlay to the DT fdt boardsetup                   - Do board-specific set up fdt move - Copy the fdt to and make it active fdt resize []          - Resize fdt to size + padding to 4k addr + some optional if needed fdt print   []       - Recursive print starting at fdt list []       - Print one level starting at fdt get value - Get and store in fdt get name - Get name of node and store in fdt get addr - Get start address of and store in fdt get size []  - Get size of [] or num nodes and store in fdt set [] - Set [to ] fdt mknode          - Create a new node after fdt rm     []       - Delete the node or fdt header                         - Display header info fdt bootcpu                   - Set boot cpuid fdt memory          - Add/Update memory node fdt rsvmem print                   - Show current mem reserves fdt rsvmem add       - Add a mem reserve fdt rsvmem delete          - Delete a mem reserves fdt chosen [ ]       - Add/update the /chosen branch in the tree                                     / - initrd start/end addr printenv:打印环境变量 setenv:设置环境变量 saveenv:保存设置的环境变量 md:显示内存区的内容 mm:修改内存 cmp:比较两块内存举报

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李秀珍

怎样通过uboot去修改sdc的频率以及以太网的delay参数呢

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李代三

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