About testing SPI, Please can you check am I right?

Robotics & Edge Computing Jetson & Embedded Systems Jetson AGX Xavier
1

OK. @ShaneCCC.

Thanks to guide me.

I did what you told me.
So, can you please check am I right?

And after that, what should I do for next step?

First, here is the list of what I did.

  1. Download L4T kernel source

  2. Modify SPI tree section on"tegra194-p2888-0001-p2822-0000-common.dtsi" file in </home/jhschai/L4T_Source/Linux_for_Tegra/source/public/hardware/nvidia/platform/t19x/galen/kernel-dts/common>
    I don’t fully understand about devicetree shown in below, but I’m sure I will use SPI1.
    ##############################################
    spi@3210000 {
    compatible = “nvidia,tegra186-spi”;
    reg = <0x0 0x3210000 0x0 0x10000>;
    interrupts = <0x0 0x24 0x4>;
    #address-cells = <0x1>;
    #size-cells = <0x0>;
    iommus = <0x2 0x20>;
    dma-coherent;
    dmas = <0x1e 0xf 0x1e 0xf>;
    dma-names = “rx”, “tx”;
    spi-max-frequency = <0x3dfd240>;
    nvidia,clk-parents = “pll_p”, “clk_m”;
    clocks = <0x4 0x87 0x4 0x66 0x4 0xe>;
    clock-names = “spi”, “pll_p”, “clk_m”;
    resets = <0x5 0x5b>;
    reset-names = “spi”;
    status = “okay”;
    linux,phandle = <0x162>;
    phandle = <0x162>;

     spi@0 {
 	compatible = "spidev";
 	reg = <0x0>;
 	spi-max-frequency = <0x1f78a40>;
 	nvidia,enable-hw-based-cs;
 	nvidia,rx-clk-tap-delay = <0x11>;
 };

 spi@1 {
 	compatible = “spidev”;
 	reg = <1>;
 	status = “okay”;
 }

};
##############################################

  1. Build kernel Source form L4T_Source with modified device-tree file.

  2. copy builded image file and dtb folder contents.

  3. Make new PINMUX.dtsi file from “Template.xlsm”.

  4. Make .cfg file with command.
    python pinmux-dts2cfg.py --pinmux addr_info.txt gpio_addr_info.txt por_val.txt --mandatory_pinmux_file mandatory_pinmux.txt tegra19x-jetson_agx_devkit-pinmux.dtsi tegra19x-jetson_agx_devkit-gpio-default.dtsi 1.0 > data.cfg

##############################################

Pinmux for gpio-input pins

pinmux.0x02212480 = 0x00000001; # CONFIG Z4

pinmux.0x0243d020 = 0x00000000; # GPIO spi1_miso_pz4

Pinmux for used pins

pinmux.0x0243d040 = 0x00000405; # spi1_sck_pz3: rsvd1, pull-down, tristate-disable, input-disable, lpdr-disable

pinmux.0x0243d020 = 0x00000055; # spi1_miso_pz4: rsvd1, pull-down, tristate-enable, input-enable, lpdr-disable

pinmux.0x0243d058 = 0x00000405; # spi1_mosi_pz5: rsvd1, pull-down, tristate-disable, input-disable, lpdr-disable

pinmux.0x0243d010 = 0x00000409; # spi1_cs0_pz6: rsvd1, pull-up, tristate-disable, input-disable, lpdr-disable

pinmux.0x0243d050 = 0x00000409; # spi1_cs1_pz7: rsvd1, pull-up, tristate-disable, input-disable, lpdr-disable
##############################################

  1. Copy contents of new .cfg file to “tegra19x-mb1-pinmux-p2888-0000-a04-p2822-0000-b01.cfg”

  2. Flash Kernel with modified PINMUX and modified device tree with command
    sudo ./flash.sh kernel-dtb jetson-xavier mmcblk0p1

  3. Re-install ubuntu at JETSON BOARD and connect [SPI1_MOSI(Header19)]&[SPI1_MISO(Header21)] to self test SPI.

This is right process to use SPI?

Second, What should I do for next step?

Please guide me little more!!

Thanks

3

The step need to flash without -k kernel-dtb to apply the cfg file.
The correct command is sudo ./flash -r jetson-xavier mmcblk0p1
And you can verify the REG setting by the devmem2 tools.

After the loopback test is OK you can connect your device and implement the driver for it.

4

@ShaneCCC.
I’ve already check REG value after flashing.

When I use devmem2 tools, REG values are setted with the value which I want.
for example,
$ sudo devmem2 0x0243d050
command return
Value at address 0x243D050( 0x7fad502050) : 0x409

I think my REGs are changed. Am I wrong?
Do I need to flash again with the command you told?

And can you tell me how to use loopback test?
what should I need to install.
sudo apt-get install spidev?

5

If the REG setting are apply as your configure file that should be fine.
Have a reference to below wiki.

https://elinux.org/Jetson/TX2_SPI#Testing_Communication

6

I’ve follow wiki.

After make spidev_test file, I copy that file to JETSON board.

And on terminal I try the command “spidev_test -D /dev/spidev0.0”.

After that I’ve got error message,
bash: spidev_test: connot find command
(it may not exactly same, because I translate it to Eng)

Can you please help me?

7

Run sudo ./spidev_test -D /dev/spidev0.0 at the spidev_test folder.

8

I’ve try it ant I got

spi mode: 0x0
bits per word: 8
max speed: 500000 hz (500KHz)
RX | 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |…

Not I shoud have check pinmux…
Can you check my pinmux value and device tree is right for test?
Each value are shown in my original post up there. (not in reply)

9

Original PINMUX.cfg value for kernel is
pinmux.0x0243d040 = 0x00000055; # spi1_sck_pz3: rsvd1, pull-down, tristate-enable, input-enable, lpdr-disable
pinmux.0x0243d020 = 0x00000055; # spi1_miso_pz4: rsvd1, pull-down, tristate-enable, input-enable, lpdr-disable
pinmux.0x0243d058 = 0x00000055; # spi1_mosi_pz5: rsvd1, pull-down, tristate-enable, input-enable, lpdr-disable
pinmux.0x0243d010 = 0x00000059; # spi1_cs0_pz6: rsvd1, pull-up, tristate-enable, input-enable, lpdr-disable
pinmux.0x0243d050 = 0x00000059; # spi1_cs1_pz7: rsvd1, pull-up, tristate-enable, input-enable, lpdr-disable

I’ve modify it to
pinmux.0x0243d040 = 0x00000405; # spi1_sck_pz3: rsvd1, pull-down, tristate-disable, input-disable, lpdr-disable
pinmux.0x0243d020 = 0x00000055; # spi1_miso_pz4: rsvd1, pull-down, tristate-enable, input-enable, lpdr-disable
pinmux.0x0243d058 = 0x00000405; # spi1_mosi_pz5: rsvd1, pull-down, tristate-disable, input-disable, lpdr-disable
pinmux.0x0243d010 = 0x00000409; # spi1_cs0_pz6: rsvd1, pull-up, tristate-disable, input-disable, lpdr-disable
pinmux.0x0243d050 = 0x00000409; # spi1_cs1_pz7: rsvd1, pull-up, tristate-disable, input-disable, lpdr-disable

And After flash I already check mem value using devmem2.

10

Have a reference to below setting.

11

Thanks.
And also find I’m wrong.

I have miss to change pin usage in xlsm files.

Thanks I will try it again