Uboot查看并修改内核设备树节点

2024-08-19 13:05:07 浏览数 (2)

Uboot查看并修改内核设备树节点

FDT命令说明

FDT：flattened device tree 的缩写在 U-Boot 控制台停下后，输入fdt，可以查看fdt命令帮助。

代码语言：javascript复制
sunxi#fdt
fdt - flattened device tree utility commands
Usage:
fdt addr [-c] <addr> [<length>] - Set the [control] fdt location to <addr>
fdt move <fdt> <newaddr> <length> - Copy the fdt to <addr> and make it active
fdt resize - Resize fdt to size   padding to 4k addr
fdt print <path> [<prop>] - Recursive print starting at <path>
fdt list <path> [<prop>] - Print one level starting at <path>
fdt get value <var> <path> <prop> - Get <property> and store in <var>
fdt get name <var> <path> <index> - Get name of node <index> and store in <var>
fdt get addr <var> <path> <prop> - Get start address of <property> and store in <var>
fdt get size <var> <path> [<prop>] - Get size of [<property>] or num nodes and store in <var>
fdt set <path> <prop> [<val>] - Set <property> [to <val>]
fdt mknode <path> <node> - Create a new node after <path>
fdt rm <path> [<prop>] - Delete the node or <property>
fdt header
fdt bootcpu <id> - Set boot cpuid
fdt memory <addr> <size> - Add/Update memory node
fdt rsvmem print - Show current mem reserves
fdt rsvmem add <addr> <size> - Add a mem reserve
fdt rsvmem delete <index> - Delete a mem reserves
fdt chosen [<start> <end>] - Add/update the /chosen branch in the tree
<start>/<end> - initrd start/end addr
NOTE: Dereference aliases by omiting the leading '/', e.g. fdt print ethernet0。

其中常用的命令就是fdt list 和 fdt set,fdt list 用来查询节点配置,fdt set 用来修改节点配置。

1. 查询配置

首先确定要查询的字段在 device tree 的路径，如果不知道路径，则需要用fdt命令按以下步骤进

行查询。1. 在根目录下查找。

代码语言：javascript复制
sunxi#fdt list /
/ {
    model = "{LICHEE_CHIP}";
    compatible = "arm,{LICHEE_CHIP}", "arm,{LICHEE_CHIP}";
    interrupt-parent = <0x00000001>;
    #address-cells = <0x00000002>;
    #size-cells = <0x00000002>;
    ......................
    cpuscfg {
    };
    ion {
    };
    dram {
    };
    memory@40000000 {
    };
    interrupt-controller@1c81000 {
    };
    sunxi-chipid@1c14200 {
    };
    timer {
    };
    pmu {
    };
    dvfs_table {
    };
    dramfreq {
    };
    gpu@0x01c40000 {
    };
    wlan {
    };
    bt {
    };
    btlpm {
    };
};

如果找到需要的配置，比如wlan的配置，运行如下命令即可。

代码语言：javascript复制
sunxi#fdt list /wlan //注意路径中的 /
wlan {
    compatible = "allwinner,sunxi-wlan";
    clocks = <0x00000096>;
    wlan_power = "vcc-wifi";
    wlan_io_regulator = "vcc-wifi-io";
    wlan_busnum = <0x00000001>;
    status = "okay";
    device_type = "wlan";
    wlan_regon = <0x00000077 0x0000000b 0x00000002 0x00000001 0xffffffff 0xffffffff 0
    x00000000>;
    wlan_hostwake = <0x00000077 0x0000000b 0x00000003 0x00000006 0xffffffff 0xffffffff
    0x00000000>;
};
  1. 在 soc目录下找。如果在第一步中没有发现要找的配置，比如nand0的配置，则该配置可能在soc目录下。
代码语言：javascript复制
sunxi#fdt list /soc
soc@01c00000 {
    compatible = "simple-bus";
    #address-cells = <0x00000002>;
    #size-cells = <0x00000002>;
    ranges;
    device_type = "soc";
    ......................
    hdmi@01ee0000 {
    };
    tr@01000000 {
    };
    pwm@01c21400 {
    };
    nand0@01c03000 {
    };
    thermal_sensor {
    };
    cpu_budget_cool {
    };
    .......................
};

然后用如下命令显示即可:

代码语言：javascript复制
sunxi#fdt list /soc/nand0
nand0@01c03000 {
    compatible = "allwinner,sun50i-nand";
    device_type = "nand0";
    reg = <0x00000000 0x01c03000 0x00000000 0x00001000>;
    interrupts = <0x00000000 0x00000046 0x00000004>;
    clocks = <0x00000004 0x0000007e>;
    pinctrl-names = "default", "sleep";
    pinctrl-1 = <0x00000081>;
    nand0_regulator1 = "vcc-nand";
    nand0_regulator2 = "none";
    nand0_cache_level = <0x55aaaa55>;
    nand0_flush_cache_num = <0x55aaaa55>;
    nand0_capacity_level = <0x55aaaa55>;
    nand0_id_number_ctl = <0x55aaaa55>;
    nand0_print_level = <0x55aaaa55>;
    nand0_p0 = <0x55aaaa55>;
    nand0_p1 = <0x55aaaa55>;
    nand0_p2 = <0x55aaaa55>;
    nand0_p3 = <0x55aaaa55>;
    status = "disabled";
    nand0_support_2ch = <0x00000000>;
    pinctrl-0 = <0x000000a9 0x000000aa>;
};
  1. 使用路径别名查找。别名是 device tree 中完整路径的一个简写，有一个专门的节点 ( /aliases) 来表示别名的相关信息，用如下命令可以查看系统中别名的配置情况：
代码语言：javascript复制
sunxi#fdt list /aliases
aliases {
    serial0 = "/soc@01c00000/uart@01c28000";
    ..............
    mmc0 = "/soc@01c00000/sdmmc@01c0f000";
    mmc2 = "/soc@01c00000/sdmmc@01C11000";
    nand0 = "/soc@01c00000/nand0@01c03000";
    disp = "/soc@01c00000/disp@01000000";
    lcd0 = "/soc@01c00000/lcd0@01c0c000";
    hdmi = "/soc@01c00000/hdmi@01ee0000";
    pwm = "/soc@01c00000/pwm@01c21400";
    boot_disp = "/soc@01c00000/boot_disp";
};
sunxi#

由于配置了nand0节点的路径别名，因此可以用如下命令来显示nand0的配置信息。

代码语言：javascript复制
sunxi#fdt list nand0
nand0@01c03000 {
    compatible = "allwinner,sun50i-nand";
    device_type = "nand0";
    reg = <0x00000000 0x01c03000 0x00000000 0x00001000>;
    ..................
    pinctrl-names = "default", "sleep";
    pinctrl-1 = <0x00000081>;
};

注：在fdt的所有命令中，alias 可以用作path参数。

代码语言：javascript复制
fdt list <path> [<prop>] - Print one level starting at <path>
fdt set <path> <prop> [<val>] - Set <property> [to <val>]
2. 修改配置
2.1 修改整数配置

命令格式：fdt set path prop 示例：fdt set /wlan wlan_busnum <0x2>

代码语言：javascript复制
sunxi#fdt list /wlan
wlan {
    compatible = "allwinner,sunxi-wlan";
    clocks = <0x00000096>;
    wlan_power = "vcc-wifi";
    wlan_io_regulator = "vcc-wifi-io";
    wlan_busnum = <0x00000001>;
    status = "disable";
    device_type = "wlan";
};
sunxi#fdt set /wlan wlan_busnum <0x2>
sunxi#fdt list /wlan
wlan {
    compatible = "allwinner,sunxi-wlan";
    clocks = <0x00000096>;
    wlan_power = "vcc-wifi";
    wlan_io_regulator = "vcc-wifi-io";
    wlan_busnum = <0x00000002>; //修改后
    status = "disable";
    device_type = "wlan";
};

注：修改整数时，根据需要也可配置为数组形式，需要用空格来分隔。命令格式：fdt set path prop <0x1 0x2 0x3>

2.2 修改字符串配置

命令格式：fdt set path prop “xxxxx” 示例：fdt set /wlan status “disable”

代码语言：javascript复制
sunxi#fdt list /wlan
wlan {
    compatible = "allwinner,sunxi-wlan";
    clocks = <0x00000096>;
    wlan_power = "vcc-wifi";
    wlan_io_regulator = "vcc-wifi-io";
    wlan_busnum = <0x00000001>;
    status = "okay";
    device_type = "wlan";
};
sunxi#fdt set /wlan status "disable"
sunxi#fdt list /wlan
wlan {
    compatible = "allwinner,sunxi-wlan";
    clocks = <0x00000096>;
    wlan_power = "vcc-wifi";
    wlan_io_regulator = "vcc-wifi-io";
    wlan_busnum = <0x00000001>;
    status = "disable"; //修改后
    device_type = "wlan";
};
sunxi#

注：修改字符串时，根据需要也可配置为数组形式，需要用空格来分隔。命令格式：fdt set path prop “string1” “string2”

3. GPIO 或者 PIN 配置特殊说明

接口对应的数字编号说明如下：

代码语言：javascript复制
#define PA 0
#define PB 1
#define PC 2
#define PD 3
#define PE 4
#define PF 5
#define PG 6
#define PH 7
#define PI 8
#define PJ 9
#define PK 10
#define PL 11
#define PM 12
#define PN 13
#define PO 14
#define PP 15
#define default 0xffffffff

Sysconfig 中描述 gpio 的形式如下：Port:端口 组内序号<功能分配><内部电阻状态><驱动能力><输出电平状态>

3.1 PIN 配置说明

Pinctrl 节点分为 cpux 和 cpus，对应的节点路径如下：Cpux : /soc/pinctrl@01c20800 Cpus:/soc/pinctrl@01f02c00

3.2 查看 PIN 配置

PIN 配置属性字段说明:

属性字段

含义

allwinner,function

对应于 sysconfig 中的主键名

allwinner,pins

对应于 sysconfig 中每个 gpio 配置中的端口名

allwinner,pname

对应于 sysconfig 中主键下面子键名字

allwinner,muxsel

功能分配

allwinner,pull

内部电阻状态

allwinner,drive

驱动能力

allwinner,data

输出电平状态

说明

其中0xffffffff表示使用默认值。

按以下方法查看cpux的 PIN 配置。

代码语言：javascript复制
sunxi#fdt list /soc/pinctrl@01c20800/lcd0
lcd0@0 {
    linux,phandle = <0x000000ab>;
    phandle = <0x000000ab>;
    allwinner,pins = "PD12", "PD13", "PD14", "PD15", "PD16", "PD17", "PD18", "PD19", "PD20", "PD21";
    allwinner,function = "lcd0";
    allwinner,pname = "lcdd0", "lcdd1", "lcdd2", "lcdd3", "lcdd4", "lcdd5", "lcdd6", "lcdd7", "lcdd8", "lcdd9";
    allwinner,muxsel = <0x00000003>;
    allwinner,pull = <0x00000000>;
    allwinner,drive = <0xffffffff>;
    allwinner,data = <0xffffffff>;
};
sunxi#

按以下方法查看cpus的 PIN 配置。

代码语言：javascript复制
sunxi# fdt list /soc/pinctrl@01f02c00/s_uart0
s_uart0@0 {
    linux,phandle = <0x000000b4>;
    phandle = <0x000000b4>;
    allwinner,pins = "PL2", "PL3";
    allwinner,function = "s_uart0";
    allwinner,pname = "s_uart0_tx", "s_uart0_rx";
    allwinner,muxsel = <0x00000002>;
    allwinner,pull = <0xffffffff>;
    allwinner,drive = <0xffffffff>;
    allwinner,data = <0xffffffff>;
};
sunxi#
3.3 修改 PIN 配置

使用fdt set命令可以修改 PIN 中相关属性字段

代码语言：javascript复制
sunxi#fdt set /soc/pinctrl@01c20800/lcd0 allwinner,drive <0x1>
sunxi#fdt list /soc/pinctrl@01c20800/lcd0
lcd0@0 {
    linux,phandle = <0x000000ab>;
    phandle = <0x000000ab>;
    allwinner,pins = "PD12", "PD13", "PD14", "PD15", "PD16", "PD17", "PD18", "PD19", "PD20", "PD21";
    allwinner,function = "lcd0";
    allwinner,pname = "lcdd0", "lcdd1", "lcdd2", "lcdd3", "lcdd4", "lcdd5", "lcdd6", "lcdd7", "lcdd8", "lcdd9";
    allwinner,muxsel = <0x00000003>;
    allwinner,pull = <0x00000000>;
    allwinner,drive = <0x00000001>;
    allwinner,data = <0xffffffff>;
};

说明

示例中该处修改会影响allwinner,pins表示的所有端口的驱动能力配置，修改allwinner,muxsel, allwinner,pull,allwinner,data的值也会产生类似效果。

3.4 GPIO 配置说明

Device tree 中 GPIO 对应关系，以 usb 中usb_id_gpio为例

代码语言：javascript复制
sunxi#fdt list /soc/usbc0
usbc0@0 {
    test = <0x00000002 0x00000003 0x12345678>;
    device_type = "usbc0";
    compatible = "allwinner,sun50i-otg-manager";
    ........
    usb_serial_unique = <0x00000000>;
    usb_serial_number = "20080411";
    rndis_wceis = <0x00000001>;
    status = "okay";
    usb_id_gpio = <0x00000030 0x00000007 0x00000009 0x00000000 0x00000001 0xffffffff 0xffffffff>;
};

对应于 device tree 中 usb_id_gpio = <0x00000030 0x00000007 0x00000009 0x00000000 0x00000001 0xffffffff 0xffffffff>，解释如下：

属性数值

含义

0x00000030

device tree 内部一个节点相关信息，这里可以略过

0x00000007

端口 PH, 即 #define PH 7

0x00000009

组内序号, 即 PH09

0x00000000

功能分配, 即将 PH09 配为输入

0x00000001

内部电阻状态, 即配为上拉

0xffffffff

驱动能力, 默认值

0xffffffff

输出电平, 默认值

如果需要修改 usb_id_gpio的配置，可按如下方式（示例修改了驱动能力，输出电平两项）：

代码语言：javascript复制
sunxi#fdt set /soc/usbc0 usb_id_gpio `<0x00000030 0x00000007 0x00000009 0x00000000 0x00000001 0x2 0x1>`
sunxi#fdt list
usbc0@0 {
    test = <0x00000002 0x00000003 0x12345678>;
    device_type = "usbc0";
    compatible = "allwinner,sun50i-otg-manager";
    ........
    usb_serial_unique = <0x00000000>;
    usb_serial_number = "20080411";
    rndis_wceis = <0x00000001>;
    status = "okay";
    usb_id_gpio = <0x00000030 0x00000007 0x00000009 0x00000000 0x00000001 0x00000002 0x00000001>; //修改ok
};
sunxi#
配置 字符串 list path 内核

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