IMX6ULL - 移植linux-imx_5.4.70_2.3.0
作者:zzssdd2
E-mail:zzssdd2@foxmail.com
一、说明
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主机系统:Ubuntu 20.04.3 LTS
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开发板:TOPEET-IMX6ULL
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Linux版本:linux-imx_5.4.70_2.3.0
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交叉编译器:gcc-arm-10.3-2021.07-x86_64-arm-none-linux-gnueabihf
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有了前面IMX6ULL-移植uboot-imx_v2020.04_5.4.70_2.3.0的基础再进行Linux移植就会方便很多。因为Linux的移植更多的是对设备树的修改,而在Uboot移植时已经修改过设备树,所以接下来会省不少事。
二、环境搭建
2.1、Linux源码
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获取NXP维护的Linux内核源码:
git clone https://source.codeaurora.org/external/imx/linux-imx
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使用命令
git tag -a
查看版本然后git checkout -b <tag name>
切换到目标版本:git checkout -b rel_imx_5.4.70_2.3.0
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接下来就基于版本源码进行linux内核移植
2.2、交叉编译器
三、编译源码
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linux源码根目录下创建编译脚本
make.sh
内容如下:#!/bin/bash # 若之前已经导入到环境变量则不需要 export PATH=$PATH:/usr/local/arm/gcc-arm-10.3-2021.07-x86_64-arm-none-linux-gnueabihf/bin # 若已经在顶层Makefile文件中指定则不需要 export ARCH=arm # 若已经在顶层Makefile文件中指定则不需要 export CROSS_COMPILE=arm-none-linux-gnueabihf- make distclean # make mrproper # For I.MX6 --> imx_v7_defconfig # For I.MX7 --> imx_v7_defconfig # For I.MX8 --> imx_v8_defconfig make imx_v7_defconfig # make menuconfig make -j $(nproc) all
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执行编译
./make.sh
并等待编译完成,如果没有错误出现说明搭建环境OK。 -
补充说明:
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make
命令/imx6ull/kernel/linux-imx_5.4.70_2.3.0$ make help Cleaning targets: clean - Remove most generated files but keep the config and enough build support to build external modules mrproper - Remove all generated files + config + various backup files distclean - mrproper + remove editor backup and patch files Configuration targets: config - Update current config utilising a line-oriented program nconfig - Update current config utilising a ncurses menu based program menuconfig - Update current config utilising a menu based program xconfig - Update current config utilising a Qt based front-end gconfig - Update current config utilising a GTK+ based front-end oldconfig - Update current config utilising a provided .config as base localmodconfig - Update current config disabling modules not loaded localyesconfig - Update current config converting local mods to core defconfig - New config with default from ARCH supplied defconfig savedefconfig - Save current config as ./defconfig (minimal config) allnoconfig - New config where all options are answered with no allyesconfig - New config where all options are accepted with yes allmodconfig - New config selecting modules when possible alldefconfig - New config with all symbols set to default randconfig - New config with random answer to all options listnewconfig - List new options olddefconfig - Same as oldconfig but sets new symbols to their default value without prompting kvmconfig - Enable additional options for kvm guest kernel support xenconfig - Enable additional options for xen dom0 and guest kernel support tinyconfig - Configure the tiniest possible kernel testconfig - Run Kconfig unit tests (requires python3 and pytest) Other generic targets: all - Build all targets marked with [*] * vmlinux - Build the bare kernel * modules - Build all modules modules_install - Install all modules to INSTALL_MOD_PATH (default: /) dir/ - Build all files in dir and below dir/file.[ois] - Build specified target only dir/file.ll - Build the LLVM assembly file (requires compiler support for LLVM assembly generation) dir/file.lst - Build specified mixed source/assembly target only (requires a recent binutils and recent build (System.map)) dir/file.ko - Build module including final link modules_prepare - Set up for building external modules tags/TAGS - Generate tags file for editors cscope - Generate cscope index gtags - Generate GNU GLOBAL index kernelrelease - Output the release version string (use with make -s) kernelversion - Output the version stored in Makefile (use with make -s) image_name - Output the image name (use with make -s) headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH (default: ./usr) Static analysers: checkstack - Generate a list of stack hogs namespacecheck - Name space analysis on compiled kernel versioncheck - Sanity check on version.h usage includecheck - Check for duplicate included header files export_report - List the usages of all exported symbols headerdep - Detect inclusion cycles in headers coccicheck - Check with Coccinelle Tools: nsdeps - Generate missing symbol namespace dependencies Kernel selftest: kselftest - Build and run kernel selftest (run as root) Build, install, and boot kernel before running kselftest on it kselftest-clean - Remove all generated kselftest files kselftest-merge - Merge all the config dependencies of kselftest to existing .config. Userspace tools targets: use "make tools/help" or "cd tools; make help" Kernel packaging: rpm-pkg - Build both source and binary RPM kernel packages binrpm-pkg - Build only the binary kernel RPM package deb-pkg - Build both source and binary deb kernel packages bindeb-pkg - Build only the binary kernel deb package snap-pkg - Build only the binary kernel snap package (will connect to external hosts) tar-pkg - Build the kernel as an uncompressed tarball targz-pkg - Build the kernel as a gzip compressed tarball tarbz2-pkg - Build the kernel as a bzip2 compressed tarball tarxz-pkg - Build the kernel as a xz compressed tarball perf-tar-src-pkg - Build perf-5.4.70.tar source tarball perf-targz-src-pkg - Build perf-5.4.70.tar.gz source tarball perf-tarbz2-src-pkg - Build perf-5.4.70.tar.bz2 source tarball perf-tarxz-src-pkg - Build perf-5.4.70.tar.xz source tarball Documentation targets: Linux kernel internal documentation in different formats from ReST: htmldocs - HTML latexdocs - LaTeX pdfdocs - PDF epubdocs - EPUB xmldocs - XML linkcheckdocs - check for broken external links (will connect to external hosts) refcheckdocs - check for references to non-existing files under Documentation cleandocs - clean all generated files make SPHINXDIRS="s1 s2" [target] Generate only docs of folder s1, s2 valid values for SPHINXDIRS are: make SPHINX_CONF={conf-file} [target] use *additional* sphinx-build configuration. This is e.g. useful to build with nit-picking config. Default location for the generated documents is Documentation/output Architecture specific targets (x86): * bzImage - Compressed kernel image (arch/x86/boot/bzImage) install - Install kernel using (your) ~/bin/installkernel or (distribution) /sbin/installkernel or install to $(INSTALL_PATH) and run lilo fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage) fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage) fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage) isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso) bzdisk/fdimage*/isoimage also accept: FDARGS="..." arguments for the booted kernel FDINITRD=file initrd for the booted kernel i386_defconfig - Build for i386 x86_64_defconfig - Build for x86_64 make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build make V=2 [targets] 2 => give reason for rebuild of target make O=dir [targets] Locate all output files in "dir", including .config make C=1 [targets] Check re-compiled c source with $CHECK (sparse by default) make C=2 [targets] Force check of all c source with $CHECK make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections make W=n [targets] Enable extra build checks, n=1,2,3 where 1: warnings which may be relevant and do not occur too often 2: warnings which occur quite often but may still be relevant 3: more obscure warnings, can most likely be ignored Multiple levels can be combined with W=12 or W=123 Execute "make" or "make all" to build all targets marked with [*] For further info see the ./README file
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nproc
命令$ nproc --help 用法:nproc [选项]... 打印当前进程可用的处理器数, 此数目可能小于实际工作数 --all 打印所拥有的处理器数目 --ignore=N 可能的话,排除 N 个处理单元 --help 显示此帮助信息并退出 --version 显示版本信息并退出
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openssl/bio.h
错误DTC arch/arm/boot/dts/imx6dl-gw560x.dtb HOSTCC scripts/extract-cert scripts/extract-cert.c:21:10: fatal error: openssl/bio.h: 没有那个文件或目录 21 | #include <openssl/bio.h> | ^~~~~~~~~~~~~~~ compilation terminated. make[1]: *** [scripts/Makefile.host:107:scripts/extract-cert] 错误 1 make: *** [Makefile:1123:scripts] 错误 2
解决方法:
缺少相关依赖库,安装即可
sudo apt install libssl-dev
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四、移植
参考NXP官方
imx6ull-14x14-evk
开发板移植
4.1、源码管理
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安装VScode
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打开VScode,然后选择
文件->打开文件夹...
选择linux源码文件夹 -
在源码根目录创建文件夹
.vscode
,然后选择文件->将工作区另存为...
保存文件名linux.code-workspace
在.vscode文件夹下,文件内容如下:{ "folders": [ { "path": ".." } ], "settings": { "files.exclude": { "**/.git": true, "**/.svn": true, "**/.hg": true, "**/CVS": true, "**/.DS_Store": true, "**/Thumbs.db": true, "arch/[!a]*": true, "arch/a[!r]*": true, "arch/ar[!m]*": true, "arch/arm64": true, "arch/arm/mach-[!i]*": true, "arch/arm/mach-i[!m]*": true, "arch/arm/configs/[!i]*": true, "arch/arm/configs/i[!m]*": true, "arch/arm/configs/im[!x]*": true, "arch/arm/boot/dts/.*": true, "arch/arm/boot/dts/[!i]*.dt*": true, "arch/arm/boot/dts/i[!m]*.dt*": true, "arch/arm/boot/dts/im[!x]*.dt*": true, "arch/arm/boot/dts/imx[!6]*.dt*": true, "arch/arm/boot/dts/imx6[!u]*.dt*": true, }, "search.exclude": { "**/node_modules": true, "**/bower_components": true, "**/*.code-search": true, "arch/[!a]*": true, "arch/a[!r]*": true, "arch/ar[!m]*": true, "arch/arm64": true, "arch/arm/mach-[!i]*": true, "arch/arm/mach-i[!m]*": true, "arch/arm/configs/[!i]*": true, "arch/arm/configs/i[!m]*": true, "arch/arm/configs/im[!x]*": true, "arch/arm/boot/dts/.*": true, "arch/arm/boot/dts/[!i]*.dt*": true, "arch/arm/boot/dts/i[!m]*.dt*": true, "arch/arm/boot/dts/im[!x]*.dt*": true, "arch/arm/boot/dts/imx[!6]*.dt*": true, "arch/arm/boot/dts/imx6[!u]*.dt*": true, } } }
该文件
"settings"
内容用来排除部分用不到的文件,以便查阅代码。
4.2、添加文件
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imx6ull-14x14-topeet-emmc.dts
cp arch/arm/boot/dts/imx6ull-14x14-evk-emmc.dts arch/arm/boot/dts/imx6ull-14x14-topeet-emmc.dts
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imx6ull-14x14-topeet.dts
cp arch/arm/boot/dts/imx6ull-14x14-evk.dts arch/arm/boot/dts/imx6ull-14x14-topeet.dts
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imx6ul-14x14-topeet.dtsi
cp arch/arm/boot/dts/imx6ul-14x14-evk.dtsi arch/arm/boot/dts/imx6ul-14x14-topeet.dtsi
4.3、修改文件
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设备树
参考IMX6ULL-移植uboot-imx_v2020.04_5.4.70_2.3.0文章的4.3.4节内容
补充:
imx6ul-14x14-topeet.dtsi
文件ov5640
节点修改pwn-gpios
和rst-gpios
为自己开发板所使用的引脚(官方evk开发板使用74lv595芯片控制):ov5640: ov5640@3c { compatible = "ovti,ov5640"; reg = <0x3c>; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_csi1>; clocks = <&clks IMX6UL_CLK_CSI>; clock-names = "csi_mclk"; /* pwn-gpios = <&gpio_spi 6 1>; rst-gpios = <&gpio_spi 5 0>; */ pwn-gpios = <&gpio1 4 1>; rst-gpios = <&gpio1 2 0>; csi_id = <0>; mclk = <24000000>; mclk_source = <0>; status = "disabled"; port { ov5640_ep: endpoint { remote-endpoint = <&csi1_ep>; }; }; };
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arch/arm/boot/dts/Makefile
文件添加imx6ull-14x14-topeet-emmc.dtb
,如下dtb-$(CONFIG_SOC_IMX6UL) += \ imx6ul-14x14-evk.dtb \ imx6ul-14x14-evk-csi.dtb \ imx6ul-14x14-evk-emmc.dtb \ imx6ul-14x14-evk-btwifi.dtb \ imx6ul-14x14-evk-btwifi-oob.dtb \ imx6ul-14x14-evk-ecspi-slave.dtb \ imx6ul-14x14-evk-ecspi.dtb \ imx6ul-14x14-evk-gpmi-weim.dtb \ imx6ul-9x9-evk.dtb \ imx6ul-9x9-evk-ldo.dtb \ imx6ul-9x9-evk-btwifi.dtb \ imx6ul-9x9-evk-btwifi-oob.dtb \ imx6ul-ccimx6ulsbcexpress.dtb \ imx6ul-ccimx6ulsbcpro.dtb \ imx6ul-geam.dtb \ imx6ul-isiot-emmc.dtb \ imx6ul-isiot-nand.dtb \ imx6ul-kontron-n6310-s.dtb \ imx6ul-kontron-n6310-s-43.dtb \ imx6ul-liteboard.dtb \ imx6ul-opos6uldev.dtb \ imx6ul-pico-hobbit.dtb \ imx6ul-pico-pi.dtb \ imx6ul-phytec-segin-ff-rdk-nand.dtb \ imx6ul-tx6ul-0010.dtb \ imx6ul-tx6ul-0011.dtb \ imx6ul-tx6ul-mainboard.dtb \ imx6ull-14x14-evk.dtb \ imx6ull-14x14-evk-emmc.dtb \ imx6ull-14x14-topeet-emmc.dtb \ imx6ull-14x14-evk-btwifi.dtb \ imx6ull-14x14-evk-btwifi-oob.dtb \ imx6ull-14x14-evk-gpmi-weim.dtb \ imx6ull-9x9-evk.dtb \ imx6ull-9x9-evk-ldo.dtb \ imx6ull-9x9-evk-btwifi.dtb \ imx6ull-9x9-evk-btwifi-oob.dtb \ imx6ull-colibri-eval-v3.dtb \ imx6ull-colibri-wifi-eval-v3.dtb \ imx6ull-phytec-segin-ff-rdk-nand.dtb \ imx6ull-phytec-segin-ff-rdk-emmc.dtb \ imx6ull-phytec-segin-lc-rdk-nand.dtb \ imx6ulz-14x14-evk.dtb \ imx6ulz-14x14-evk-btwifi.dtb \ imx6ulz-14x14-evk-gpmi-weim.dtb \ imx6ulz-14x14-evk-emmc.dtb
修改完成后执行./make.sh
等待编译完成。编译完成后在arch/arm/boot/
目录下生成内核镜像文件zImage
,在目录arch/arm/boot/dts/
下生成设备树二进制文件imx6ull-14x14-topeet-emmc.dtb
五、验证
5.1、SD卡方式
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查看SD卡挂载在系统中的名称:
cat /proc/partitions
,我的是sdb
,包含两个分区sdb1
、sdb2
$ cat /proc/partitions major minor #blocks name 7 0 4 loop0 7 1 101828 loop1 7 2 101824 loop2 7 3 56772 loop3 7 4 63252 loop4 7 5 56768 loop5 7 6 63316 loop6 7 7 166776 loop7 11 0 1048575 sr0 8 0 104857600 sda 8 1 83884032 sda1 7 8 224248 loop8 7 9 224256 loop9 7 10 247156 loop10 7 11 2544 loop11 7 12 168712 loop12 7 13 276 loop13 7 14 548 loop14 7 15 2540 loop15 7 16 248160 loop16 7 17 548 loop17 7 18 2560 loop18 7 19 704 loop19 7 20 52180 loop20 7 21 66776 loop21 7 22 2288 loop22 7 23 66660 loop23 8 16 30578688 sdb 8 17 1048576 sdb1 8 18 29512704 sdb2
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使用
fdisk
工具对SD卡进行格式化和分区:sudo fdisk /dev/sdx
注意:在使用
fdisk
工具前先将设备卸载:sudo umount /dev/sdx
$ sudo fdisk /dev/sdb 欢迎使用 fdisk (util-linux 2.34)。 更改将停留在内存中,直到您决定将更改写入磁盘。 使用写入命令前请三思。 命令(输入 m 获取帮助): m 帮助: DOS (MBR) a 开关 可启动 标志 b 编辑嵌套的 BSD 磁盘标签 c 开关 dos 兼容性标志 常规 d 删除分区 F 列出未分区的空闲区 l 列出已知分区类型 n 添加新分区 p 打印分区表 t 更改分区类型 v 检查分区表 i 打印某个分区的相关信息 杂项 m 打印此菜单 u 更改 显示/记录 单位 x 更多功能(仅限专业人员) 脚本 I 从 sfdisk 脚本文件加载磁盘布局 O 将磁盘布局转储为 sfdisk 脚本文件 保存并退出 w 将分区表写入磁盘并退出 q 退出而不保存更改 新建空磁盘标签 g 新建一份 GPT 分区表 G 新建一份空 GPT (IRIX) 分区表 o 新建一份的空 DOS 分区表 s 新建一份空 Sun 分区表
格式化SD卡:
命令(输入 m 获取帮助): d 分区号 (1,2, 默认 2): 1 分区 1 已删除。 命令(输入 m 获取帮助): d 已选择分区 2 分区 2 已删除。 命令(输入 m 获取帮助): d 还没有定义分区! 命令(输入 m 获取帮助):
SD卡重新分区:
分区如下:
- 前面4M空间留给uboot
- uboot空间之后建立分区1给内核和设备树
- 分区一之后建立分区2给根文件系统
命令(输入 m 获取帮助): n 分区类型 p 主分区 (0个主分区,0个扩展分区,4空闲) e 扩展分区 (逻辑分区容器) 选择 (默认 p): 将使用默认回应 p。 分区号 (1-4, 默认 1): 第一个扇区 (2048-61157375, 默认 2048): 8192 Last sector, +/-sectors or +/-size{K,M,G,T,P} (8192-61157375, 默认 61157375): 2105344 创建了一个新分区 1,类型为“Linux”,大小为 1 GiB。 命令(输入 m 获取帮助): n 分区类型 p 主分区 (1个主分区,0个扩展分区,3空闲) e 扩展分区 (逻辑分区容器) 选择 (默认 p): 将使用默认回应 p。 分区号 (2-4, 默认 2): 第一个扇区 (2048-61157375, 默认 2048): 2105345 Last sector, +/-sectors or +/-size{K,M,G,T,P} (2105345-61157375, 默认 61157375): 创建了一个新分区 2,类型为“Linux”,大小为 28.2 GiB。
查看SD卡分区情况
命令(输入 m 获取帮助): p Disk /dev/sdb:29.17 GiB,31312576512 字节,61157376 个扇区 Disk model: Multi-Card 单元:扇区 / 1 * 512 = 512 字节 扇区大小(逻辑/物理):512 字节 / 512 字节 I/O 大小(最小/最佳):512 字节 / 512 字节 磁盘标签类型:dos 磁盘标识符:0x00000000 设备 启动 起点 末尾 扇区 大小 Id 类型 /dev/sdb1 8192 2105344 2097153 1G 83 Linux /dev/sdb2 2105345 61157375 59052031 28.2G 83 Linux
保存分区
命令(输入 m 获取帮助): w 分区表已调整。 正在同步磁盘。
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将
uboot
写入SD卡$ sudo dd if=u-boot-dtb.imx of=/dev/sdb bs=1k seek=1 conv=fsync 记录了519+0 的读入 记录了519+0 的写出 531456字节(531 kB,519 KiB)已复制,0.239474 s,2.2 MB/s
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将内核镜像和设备树文件写入SD卡
格式化分区1为
VFAT
格式:sudo mkfs.vfat /dev/sdx1
$ sudo umount /dev/sdb1 $ sudo mkfs.vfat /dev/sdb1
挂载分区并将文件写入分区:
$ mkdir mountpoint $ sudo mount /dev/sdb1 mountpoint $ sudo cp kernel/linux-imx_5.4.70_2.3.0/arch/arm/boot/zImage mountpoint/ $ sudo cp kernel/linux-imx_5.4.70_2.3.0/arch/arm/boot/dts/imx6ull-14x14-topeet-emmc.dtb mountpoint/ $ sudo umount mountpoint
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从SD卡启动并进入uboot模式
# uboot模式下执行如下命令设置启动命令,从SD卡加载内核镜像和设备树 setenv bootcmd 'fatload mmc 0:1 80800000 zImage;fatload mmc 0:1 83000000 imx6ull-14x14-topeet-emmc.dtb;bootz 80800000 - 83000000' # 保存 saveenv # 重新启动 reset
重新启动然后在经过Uboot读秒之后可以看到Linux内核的启动信息Starting kernel ...
最后会报根文件系统无法挂载的错误信息,因为此时还没有可挂载根文件系统:
[ 2.799286] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[ 2.807567] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]---
补充:Linux系统
dd
命令使用说明
$ dd --help
用法:dd [操作数] ...
或:dd 选项
复制文件,依照指定操作数转换并格式化。
bs=字节数 一次读写的比特数(默认:512);
会覆盖 ibs 和 obs 选项
cbs=字节数 一次转换的字节数
conv=CONVS 依照每个逗号分割的符号列表转换文件
count=块数 只将复制指定数量的输入块
ibs=字节数 一次读取的字节数(默认:512)
if=文件 从指定文件而非标准输入来进行读取
iflag=标志 按照以逗号分隔的符号列表指定的方式读取
obs=字节数 一次写入指定字节数(默认:512)
of=文件 写入到指定文件而非标准输出
oflag=标志 按照以逗号分隔的符号列表指定的方式写入
seek=块数 在输出开始处跳过指定的 obs 大小的块数
skip=块数 在输入开始处跳过指定的 ibs 大小的块数
status=等级 要输出到标准错误的信息等级;
'none' 将仅输出错误信息,
'noxfer' 将不输出最终传输统计信息,
'progress' 将显示周期性的传输统计信息
N and BYTES may be followed by the following multiplicative suffixes:
c =1, w =2, b =512, kB =1000, K =1024, MB =1000*1000, M =1024*1024, xM =M,
GB =1000*1000*1000, G =1024*1024*1024, and so on for T, P, E, Z, Y.
Each CONV symbol may be:
ascii from EBCDIC to ASCII
ebcdic from ASCII to EBCDIC
ibm from ASCII to alternate EBCDIC
block pad newline-terminated records with spaces to cbs-size
unblock replace trailing spaces in cbs-size records with newline
lcase change upper case to lower case
ucase change lower case to upper case
sparse try to seek rather than write the output for NUL input blocks
swab swap every pair of input bytes
sync pad every input block with NULs to ibs-size; when used
with block or unblock, pad with spaces rather than NULs
excl 如果输出文件已存在则认为操作失败
nocreat 不要创建输出文件
notrunc 不要截断输出文件
noerror 读取数据发生错误后仍然继续
fdatasync 结束前将输出文件数据物理上写入磁盘
fsync 与上者类似,但也将元数据一同写入
FLAG 符号可以是:
append 追加模式(仅对输出有意义;隐含了conv=notrunc)
direct 使用直接I/O 存取模式
directory 除非是目录,否则操作失败
dsync 使用同步 I/O 存取模式
sync 与上者类似,但同时也对元数据生效
fullblock 为输入积累完整块(仅iflag)
nonblock 使用无阻塞I/O 存取模式
noatime 不更新访问时间
nocache 请求不使用缓存。参见 oflag=sync
noctty 不根据文件指派控制终端
nofollow 不跟随链接文件
count_bytes 把 'count=N' 看作字节计数(仅 iflag)
skip_bytes 把 'skip=N' 看作字节计数(仅 iflag)
seek_bytes 把 'seek=N' 看作字节计数(仅 oflag)
向正在运行的 'dd' 进程发送 USR1 信号可以令其向标准错误输出 I/O
统计数据并继续进行复制。
选项有:
--help 显示此帮助信息并退出
--version 显示版本信息并退出
GNU coreutils 在线帮助:<https://www.gnu.org/software/coreutils/>
请向 <http://translationproject.org/team/zh_CN.html> 报告 dd 的翻译错误
完整文档请见:<https://www.gnu.org/software/coreutils/dd>
或者在本地使用:info '(coreutils) dd invocation'