0. Preface
The V853 chip of the 100ASK_V853-PRO development board integrates Arm Cortex-A7 and RISC-V E907 dual CPUs. Xuantie E907 is a fully comprehensive high-end MCU processor. It is compatible with the RV32IMAC instruction set, providing considerable integer performance improvements and energy-efficient floating-point performance. Key features of the E907 include: single and double precision floating-point units, and fast interrupt response. The figure below is the introduction of RISC-V E907 core.
This chapter mainly describes how to develop the E907 small core and communicate with the Arm A7 large core.
Pingtouge E907 official website: https://www.t-head.cn/product/E907?spm=a2ouz.12986968.0.0.7bfc2cbdcYnL2b
E907 chip resource download center: https://occ.t-head.cn/community/download?id=3916180248689188864
Allwinner E907 Development Guide: https://tina.100ask.net/SdkModule/Linux_E907_DevelopmentGuide-01/
V85x E907 small core development and use of Yuzuki: https://www.gloomyghost.com/live/20230215.aspx
1. Configure the E907 environment
E907_RTOS BSP package: https://github.com/YuzukiHD/Yuzukilizard/tree/master/Software/BSP/e907_rtos
E907 compilation toolchain: https://github.com/YuzukiHD/Yuzukilizard/releases/download/Compiler.0.0.1/riscv64-elf-x86_64-20201104.tar.gz
Thanks to Yuzuki's V851S warehouse for providing the E907_RTOS source code. Here I put the E907 development kit in the Baidu network disk for easy access. The link is:
Link: https://pan.baidu.com/s/1TX742vfEde9bMLd9IrwwqA?pwd=sp6a
Extraction code: sp6a
You can get it from the 09_E907 development kit in the V853 data CD of Baidu Netdiske907_rtos.tar.gz
1.1 Compile E907 source code
Place the downloaded E907 development kit in any directory, assuming it is in /home/book/workspacesthe directory
book@100ask:~/workspaces$ ls
e907_rtos.tar.gz
Unzip the e907 source code package, enter tar -xzvf e907_rtos.tar.gz , for example:
book@100ask:~/workspaces$ tar -xzvf e907_rtos.tar.gz
e907_rtos/
e907_rtos/README.md
e907_rtos/rtos/
e907_rtos/rtos/LICENSE
e907_rtos/rtos/toolchain/
e907_rtos/rtos/toolchain/riscv64-elf-x86_64-20201104/
e907_rtos/rtos/toolchain/riscv64-elf-x86_64-20201104/libexec/
e907_rtos/rtos/toolchain/riscv64-elf-x86_64-20201104/libexec/gcc/
...
After the decompression is complete, enter the e907 source code directory
book@100ask:~/workspaces$ cd e907_rtos/
book@100ask:~/workspaces/e907_rtos$ ls
README.md rtos rtos-hal
enter rtos/source/the directory
book@100ask:~/workspaces/e907_rtos$ cd rtos/source/
book@100ask:~/workspaces/e907_rtos/rtos/source$ ls
disfunc.sh ekernel envsetup.sh Kbuild Kconfig.melis Makefile modules.order platform.txt scripts
drivers emodules include Kconfig Kconfig.platform melis-env.sh out projects tools
Configure the compilation environment variables, entersource melis-env.sh
book@100ask:~/workspaces/e907_rtos/rtos/source$ source melis-env.sh
Enter lunchthe selected corresponding development board
book@100ask:~/workspaces/e907_rtos/rtos/source$ lunch
You're building on Linux 100ask 5.4.0-148-generic #165~18.04.1-Ubuntu SMP Thu Apr 20 01:14:06 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
Lunch menu... pick a combo:
The supported board:
1. v851-e907-lizard
2. v851-e907-lizard-tinymaix
3. v853-e907-100ask
4. v853-e907-100ask-tinymaix
What is your choice?
Now enter 3 and press Enter. Select v853-e907-100askthe scheme, after the selection is completed, it will be as follows
book@100ask:~/workspaces/e907_rtos/rtos/source$ lunch
You're building on Linux 100ask 5.4.0-148-generic #165~18.04.1-Ubuntu SMP Thu Apr 20 01:14:06 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
Lunch menu... pick a combo:
The supported board:
1. v851-e907-lizard
2. v851-e907-lizard-tinymaix
3. v853-e907-100ask
4. v853-e907-100ask-tinymaix
What is your choice? 3
You have select v853-e907-100ask
============================================
Project Based On Platform sun20iw3p1 v853-e907-100ask
============================================
At this point you can compile, entermake
book@100ask:~/workspaces/e907_rtos/rtos/source$ make
scripts/kconfig/conf --silentoldconfig Kconfig
CHK include/config/kernel.release
CHK include/generated/uapi/melis/version.h
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
UPD include/generated/uapi/melis/version.h
CHK include/generated/utsrelease.h
CC sysconfig.fex
CC ekernel/arch/common/common.o
LD ekernel/arch/common/built-in.o
AS ekernel/arch/riscv/sunxi/blobdata.o
LD ekernel/arch/riscv/sunxi/built-in.o
LD ekernel/arch/riscv/built-in.o
LD ekernel/arch/built-in.o
LD ekernel/built-in.o
LD [M] ekernel/melis30.o
/home/book/workspaces/e907_rtos/rtos/source/../toolchain/riscv64-elf-x86_64-20201104//bin/riscv64-unknown-elf-ld: ekernel/melis30.o: section .dram_seg.stack lma 0x43c3a2b8 adjusted to 0x43c3a34c
OBJCOPY ekernel/melis30.bin
RENAME ekernel/melis30.o ----> ekernel/melis30.elf
/home/book/workspaces/e907_rtos/rtos/source/../toolchain/riscv64-elf-x86_64-20201104//bin/riscv64-unknown-elf-strip: ekernel/stW7SdkR: section .dram_seg.stack lma 0x43c3a2b8 adjusted to 0x43c3a34c
text data bss dec hex filename
221280 17132 25488 263900 406dc ekernel/melis30.elf
pack melis
#### make completed successfully (11 seconds) ####
ekernel/After the compilation is complete, a melis30.elffile will be generated under the current directory , which can be used to start the small core.
1.2 E907 Configuration Items
The configuration of the E907 development kit is similar to that of the Tina SDK. In e907_rtos/rtos/sourcethe directory, executemake menuconfig
For example:
book@100ask:~/workspaces/e907_rtos/rtos/source$ make menuconfig
After the execution is completed, you will enter the following interface:
2. Load E907 small core
2.1 Tina configuration
2.1.1 Device tree configuration
In the Tina root directory, enter the device tree directory
book@100ask:~/workspaces/tina-v853-open$ cd device/config/chips/v853/configs/100ask/
Edit device tree
book@100ask:~/workspaces/tina-v853-open/device/config/chips/v853/configs/100ask$ vi board.dts
Find the device tree node related to E907 in the device tree file. The default setting of the device tree is:
reserved-memory {
e907_dram: riscv_memserve {
reg = <0x0 0x48000000 0x0 0x00400000>;
no-map;
};
vdev0buffer: vdev0buffer@47000000 {
/* 256k reserved for shared mem pool */
compatible = "shared-dma-pool";
reg = <0x0 0x47000000 0x0 0x40000>;
no-map;
};
vdev0vring0: vdev0vring0@47040000 {
reg = <0x0 0x47040000 0x0 0x20000>;
no-map;
};
vdev0vring1: vdev0vring1@47060000 {
reg = <0x0 0x47060000 0x0 0x20000>;
no-map;
};
};
e907_rproc: e907_rproc@0 {
compatible = "allwinner,sun8iw21p1-e907-rproc";
clock-frequency = <600000000>;
memory-region = <&e907_dram>, <&vdev0buffer>,
<&vdev0vring0>, <&vdev0vring1>;
mboxes = <&msgbox 0>;
mbox-names = "mbox-chan";
iommus = <&mmu_aw 5 1>;
memory-mappings =
/* DA len PA */
/* DDR for e907 */
< 0x48000000 0x00400000 0x48000000 >;
core-name = "sun8iw21p1-e907";
firmware-name = "melis-elf";
status = "okay";
};
rpbuf_controller0: rpbuf_controller@0 {
compatible = "allwinner,rpbuf-controller";
remoteproc = <&e907_rproc>;
ctrl_id = <0>; /* index of /dev/rpbuf_ctrl */
iommus = <&mmu_aw 5 1>;
status = "okay";
};
rpbuf_sample: rpbuf_sample@0 {
compatible = "allwinner,rpbuf-sample";
rpbuf = <&rpbuf_controller0>;
status = "okay";
};
Since we need to use uart3the print information of the E907 small core, in order to prevent kernel preemption uart3, we need to disable uart3the node
&uart3 {
pinctrl-names = "default", "sleep";
pinctrl-0 = <&uart3_pins_active>;
pinctrl-1 = <&uart3_pins_sleep>;
uart-supply = <®_dcdc1>;
status = "okay";
};
Modify device tree reuse
uart3_pins_active: uart3@0 {
allwinner,pins = "PH0", "PH1";
allwinner,function = "uart3";
allwinner,muxsel = <5>;
allwinner,drive = <1>;
allwinner,pull = <1>;
};
uart3_pins_sleep: uart3@1 {
allwinner,pins = "PH0", "PH1";
allwinner,function = "gpio_in";
allwinner,muxsel = <0>;
};
2.1.2 Kernel configuration
In the Tina root directory, execute make kernel_menuconfig, for example:
book@100ask:~/workspaces/tina-v853-open$ make kernel_menuconfig
1. Enable hardware support
After entering the kernel configuration interface, enter Device Drivers the directory and select it Mailbox Hardware Support, as shown in the figure below
After selecting, enter Mailbox Hardware Supportthe directory, select sunxi Mailboxand sunxi rv32 standby driver, and the selection is completed, as shown in the figure below:
2. Enable the RPMsg driver
Enter the following directory
→ Device Drivers
→ Rpmsg drivers
Select the following configuration
<*> allwinnertech rpmsg driver for v853-e907
<*> allwinnertech rpmsg hearbeat driver
<*> sunxi rpmsg ctrl driver
<*> Virtio RPMSG bus driver
After the selection is completed, it will be shown as the following figure:
3. Enable the shared memory driver
Enter the following directory
→ Device Drivers
→ Remoteproc drivers
Select the following configuration
<*> SUNXI remote processor support --->
As shown below:
After modification, save the kernel configuration and exit.
2.1.3 Compile a new image
In the root directory of Tina, enter and makecompile the kernel driver you just selected. After the compilation is complete, enter packand package to generate a new image. For example:
book@100ask:~/workspaces/tina-v853-open$ make
...
book@100ask:~/workspaces/tina-v853-open$ pack
...
After generating a new image, copy the generated v853_linux_100ask_uart0.imgfile to the Windows host.
2.2 E907 configuration
2.2.1 Modify the E907 link script
Enter the directory e907_rtos/rtos/source/projects/v853-e907-100askand find kernel.ldsthe file, which saves the link information of the E907 small core.
book@100ask:~/workspaces/e907_rtos/rtos/source/projects/v853-e907-100ask$ ls
configs data epos.img kernel.lds src version
Modify kernel.lds, find MEMORYthe node, modify the starting address to 0x48000000, and the length to 0x00400000. This parameter needs to be consistent with the E907 memory parameter in the Tina device tree, so the modifiable MEMORYnode parameters are:
MEMORY
{
/*DRAM_KERNEL: 4M */
DRAM_SEG_KRN (rwx) : ORIGIN = 0x48000000, LENGTH = 0x00400000
}
The comparison chart between the two is as follows:
What is used here 0x48000000is assuming that V853 has 128M of memory, and the hexadecimal value can be set to be 0x48000000; the length is 4M, and the hexadecimal value is0x00400000
2.2.2 Modify E907 configuration
Enter e907_rtos/rtos/source/projects/v853-e907-100ask/configsthe directory and modify defconfigthe file, for example:
book@100ask:~/workspaces/e907_rtos/rtos/source/projects/v853-e907-100ask$ cd configs/
book@100ask:~/workspaces/e907_rtos/rtos/source/projects/v853-e907-100ask/configs$ ls
defconfig sys_config.fex
Modify the following three parameters to:
CONFIG_DRAM_PHYBASE=0x48000000
CONFIG_DRAM_VIRTBASE=0x48000000
CONFIG_DRAM_SIZE=0x0400000
As shown below:
2.2.3 Use uart3 to output information
1. Modify pin multiplexing
Configure the pin multiplexing file and enter e907_rtos/rtos/source/projects/v853-e907-100ask/configsthe directory
Modify sys_config.fexthe file, check the pin multiplexing function by querying the data sheet, we use PH0 and PH1 as uart3the function
Modify the uart3 node as:
[uart3]
uart_tx = port:PH00<5><1><default><default>
uart_rx = port:PH01<5><1><default><default>
2. Modify the configuration
e907_rtos/rtos/sourceEnter in the directory make menuconfigto enter the E907 configuration interface
Enter the following directory, select[*] Support Serial Driver
→ Kernel Setup
→ Drivers Setup
→ Melis Source Support
[*] Support Serial Driver
Enter the following directory, select it [*] enable sysconfig, and enable the function of reading and parsing sys_config.fex
→ Kernel Setup
→ Drivers Setup
→ SoC HAL Drivers
→ Common Option
[*] enable sysconfig
Enter the following directory, enable the uart driver, and use uart3.
→ Kernel Setup
→ Drivers Setup
→ SoC HAL Drivers
→ UART Devices
[*] enable uart driver
[*] support uart3 device
(3) cli uart port number
Enter the following directory and enable the sys_config.fex parser
→ Kernel Setup
→ Subsystem support
→ devicetree support
[*] support traditional fex configuration method parser.
Save and exit E907 configuration.
2.2.4 Compile and generate a new image
In workspaces/e907_rtos/rtos/sourcethe directory, entermake
book@100ask:~/workspaces/e907_rtos/rtos/source$ make
CHK include/config/kernel.release
CHK include/generated/uapi/melis/version.h
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
fatal: not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
UPD include/generated/uapi/melis/version.h
CHK include/generated/utsrelease.h
CC sysconfig.fex
CC ekernel/arch/common/common.o
LD ekernel/arch/common/built-in.o
AS ekernel/arch/riscv/sunxi/blobdata.o
LD ekernel/arch/riscv/sunxi/built-in.o
LD ekernel/arch/riscv/built-in.o
LD ekernel/arch/built-in.o
LD ekernel/built-in.o
LD [M] ekernel/melis30.o
/home/book/workspaces/e907_rtos/rtos/source/../toolchain/riscv64-elf-x86_64-20201104//bin/riscv64-unknown-elf-ld: ekernel/melis30.o: section .dram_seg.stack lma 0x4803a2b8 adjusted to 0x4803a34c
OBJCOPY ekernel/melis30.bin
RENAME ekernel/melis30.o ----> ekernel/melis30.elf
/home/book/workspaces/e907_rtos/rtos/source/../toolchain/riscv64-elf-x86_64-20201104//bin/riscv64-unknown-elf-strip: ekernel/stWPSq13: section .dram_seg.stack lma 0x4803a2b8 adjusted to 0x4803a34c
text data bss dec hex filename
221280 17132 25488 263900 406dc ekernel/melis30.elf
pack melis
#### make completed successfully (7 seconds) ####
After the compilation is complete, it will ekernelbe generated in the directory melis30.elf.
2.3 Check the development board hardware
After testing, it is found that the R36 resistor on the 100ASK_V853-PRO development board will cause uart3the baud rate to be too high, so it is necessary to check whether the R36 resistor on the development board exists, and if it exists, it needs to be removed manually. The figure below shows the location of the R36 resistor, and the red box is the R36 resistor
If the resistor needs to be removed manually, the following figure is a schematic diagram of removing the R36 resistor
After removing the R36 resistor, uart3the serial port can be accessed normally.
2.4 Enable E907 in the development board
Use the Allwinner programming tool AllwinnertechPhoeniSuitto update the new image of Tina, for details, please refer to https://forums.100ask.net/t/topic/2882
After the update is complete, open the serial port terminal to enter the development board console, and melis30.elfcopy it to /lib/firmwarethe directory.
Suppose I use the ADB function to copy the file to root/the directory of the development board
root@TinaLinux:~# cd /root/
root@TinaLinux:~# ls
melis30.elf
Copy rootthe contents of the directory melis30.elfto /lib/firmwarethe directory
root@TinaLinux:~# cp melis30.elf /lib/firmware/
root@TinaLinux:~# ls /lib/firmware/
boot_xr829.bin fw_xr829.bin melis30.elf sdd_xr829.bin
etf_xr829.bin fw_xr829_bt.bin regulatory.db
After the copy is complete, you can /lib/firmwaresee the small core firmware in the directory.
2.4.1 Connect the uart3 of the development board
At this time, you need to use the USB-to-serial port module to connect to the one we set above uart3. We need to find PH0, PH1, and GND on the development board, and connect them to RXD, TXD, and GND of the USB-to-serial module, respectively. The 100ASK_V853-PRO development board has led out PH0, PH1, and GND, as shown in the location diagram below
For specific pins, you can check the silkscreen on the back of the development board to confirm the pin positions.
The positions of PH0, PH1, and GND can be known through the silk screen on the back. As shown in the figure below, PH0, PH1, and GND are respectively connected to RX, TX, and GND of the USB-to-serial port module.
After the connection is complete, insert the USB-to-serial port module into the windows host, and use the serial port software to open the uart3 serial port interface with a baud rate of 115200.
Enter in the serial port terminal of the Tina Linux development board
root@TinaLinux:~# echo melis30.elf > /sys/kernel/debug/remoteproc/remoteproc0/firmware
Put melis30.elfthe firmware under the hardware node firmware and start the E907 firmware
root@TinaLinux:~# echo start > /sys/kernel/debug/remoteproc/remoteproc0/state
[ 3926.510018] remoteproc0: powering up e907_rproc
[ 3926.515440] remoteproc0: failed to parser head (melis30.elf) ret=-2
[ 3926.522674] remoteproc0: failed to read boot_package item
[ 3926.528930] remoteproc0: request_firmware failed from boot_package: -14
[ 3926.537528] virtio_rpmsg_bus virtio0: rpmsg host is online
[ 3926.543964] remoteproc0: registered virtio0 (type 7)
[ 3926.550538] remoteproc0: remote processor e907_rproc is now up
root@TinaLinux:~# [ 3926.560537] virtio_rpmsg_bus virtio0: creating channel rpbuf-service addr 0x400
[ 3926.569199] virtio_rpmsg_bus virtio0: creating channel sunxi,rpmsg_heartbeat addr 0x401
[ 3926.578725] virtio_rpmsg_bus virtio0: creating channel sunxi,notify addr 0x402
[ 3926.587194] virtio_rpmsg_bus virtio0: creating channel sunxi,rpmsg_ctrl addr 0x403
After enabling it, you can see the following print information on another serial port interface
|commitid:
|halgitid:
|timever : Thu, 04 May 2023 04:22:23 -0400
scheduler startup
msh >Start Rpmsg Hearbeat Timer
rpmsg ctrldev: Start Running...
Press Enter to enter the terminal interface.
Enter psto see the small core process information
msh >ps
thread pri status sp stack size max used left tick error
-------------------------------- --- ------- ---------- ---------- ------ ---------- ---
tshell 21 ready 0x000003e8 0x00004000 19% 0x00000008 000
ctrldev 6 suspend 0x00000148 0x00001000 08% 0x0000000a 000
rpmsg_srm 8 suspend 0x000000f8 0x00000800 22% 0x0000000a 000
vring-ipi 15 suspend 0x00000118 0x00002000 03% 0x0000000a 000
rpbuf_init 8 suspend 0x000000e8 0x00001000 12% 0x0000000a 000
standby 1 suspend 0x00000128 0x00001000 07% 0x0000000a 000
tidle 31 ready 0x00000178 0x00002000 04% 0x0000001e 000
timer 8 suspend 0x000000d8 0x00000200 73% 0x0000000a 000
3. Binuclear communication
3.1 E907 small core to create a communication node
Establish two communication nodes on the E907 small-core serial port terminal to monitor data, inputeptdev_bind test 2
msh >eptdev_bind test 2
To view the listening node, enterrpmsg_list_listen
msh >rpmsg_list_listen
name listen alive
test 2 0
console 100 0
3.2 Large core creates communication nodes
Also create two communication monitoring nodes under Tina LInux, enter the following two commands
echo test > /sys/class/rpmsg/rpmsg_ctrl0/open
echo test > /sys/class/rpmsg/rpmsg_ctrl0/open
After entering, it looks like this:
root@TinaLinux:~# echo test > /sys/class/rpmsg/rpmsg_ctrl0/open
[ 5060.227158] virtio_rpmsg_bus virtio0: creating channel sunxi,rpmsg_client addr 0x404
s/rpmsg/rpmsg_ctrl0/openroot@TinaLinux:~# echo test > /sys/class/rpmsg/rpmsg_ctrl0/open
[ 5061.464758] virtio_rpmsg_bus virtio0: creating channel sunxi,rpmsg_client addr 0x405
Two monitoring nodes are also created in the big core TIna Linux, enter to ls /dev/rpmsg*view the node information
root@TinaLinux:~# ls /dev/rpmsg*
/dev/rpmsg0 /dev/rpmsg1 /dev/rpmsg_ctrl0
After the creation is complete, you can view the automatically output information in the E907 small core terminal.
msh >ctrldev: Rx 44 Bytes
client: Rx 8 Bytes
rpmsg0: binding
send 0x13131411 to rpmsg0
create rpmsg0 client success
ctrldev: Rx 44 Bytes
client: Rx 8 Bytes
rpmsg1: binding
send 0x13131411 to rpmsg1
create rpmsg1 client success
3.3 Transfer from large core to E907 small core
Type in Tina LInux
echo "hello 100ASK_V853-PRO" > /dev/rpmsg0
echo "hello Tina Linux" > /dev/rpmsg1
Transfer Linux Message 0the information to the E907 small core through the created listening node, for example:
root@TinaLinux:~# echo "hello 100ASK_V853-PRO" > /dev/rpmsg0
root@TinaLinux:~# echo "hello Tina Linux" > /dev/rpmsg1
After inputting, open the E907 serial port terminal to find the information transmitted by the big core.
rpmsg0: Rx 22 Bytes
Data:hello 100ASK_V853-PRO
rpmsg1: Rx 17 Bytes
Data:hello Tina Linux
3.4 Transfer from E907 small core to large core
eptdev_send You need to use the command usage on the small core side . The number eptdev_send <id> <data>here starts from 0. We set up two communication nodes, so the id numbers are 0 and 1 respectively.id
Enter the following command on the serial terminal of the small core:
eptdev_send 0 "hello E907"
eptdev_send 1 "hello E907"
For example:
msh >eptdev_send 0 "hello E907"
will send hello E907 to rpmsg0
msh >eptdev_send 1 "hello E907"
will send hello E907 to rpmsg1
After the input is completed, the small core will transfer the information to the two communication nodes rpmsg0 and rpmsg1 respectively. It can be input on the big core Tina Linux side
cat /dev/rpmsg0
cat /dev/rpmsg1
You can view the information transmitted from the E907 small core. For example:
root@TinaLinux:~# cat /dev/rpmsg0
hello E907
^C
root@TinaLinux:~# cat /dev/rpmsg1
hello E907
^C
Press Crtl+C to continue monitoring the node before ending the monitoring.
You can transmit information to this node multiple times on the small core side, and this node supports continuous acceptance of information transmitted by the small core, for example:
In the E907 small core, transmit information to the listening node multiple timesrpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
msh >eptdev_send 0 "hello E907 "
will send hello E907 to rpmsg0
At the end of the large core, it will always receive the information transmitted by the small core
root@TinaLinux:~# cat /dev/rpmsg0
hello E907 hello E907 hello E907 hello E907 hello E907 hello E907 hello E907
3.5 Closing communication
On the big-core Tina Linux side, just operate the node, enter the following command, echo <id>give the control of rpmsg to close the node
echo 0 > /sys/class/rpmsg/rpmsg_ctrl0/close
echo 1 > /sys/class/rpmsg/rpmsg_ctrl0/close
For example:
root@TinaLinux:~# echo 0 > /sys/class/rpmsg/rpmsg_ctrl0/close
[ 6783.156899] virtio_rpmsg_bus virtio0: destroying channel sunxi,rpmsg_client addr 0x404
root@TinaLinux:~# echo 1 > /sys/class/rpmsg/rpmsg_ctrl0/close
root@TinaLinux:~# [ 6784.224740] virtio_rpmsg_bus virtio0: destroying channel sunxi,rpmsg_client addr 0x405
At this time, the E907 small core terminal will also automatically close the communication node, and automatically output the following information
send 0x13131411 to rpmsg0
rpmsg0: unbinding
ctrldev: Rx 44 Bytes
send 0x13131411 to rpmsg1
rpmsg1: unbinding