Hi @nmohan86,
Sorry for the delay, after debugging the driver, I was able to solve this issue. Turns out there is a property on the device tree that is required and I missed, even though is not well documented as required on the iMX RPMSG documentation from NXP. Here is the new overlay:
/dts-v1/;
/plugin/;
#include <dt-bindings/firmware/imx/rsrc.h>
/ {
compatible = "toradex,colibri-imx8x";
};
&{/} {
reserved-memory {
#address-cells = <2>;
#size-cells = <2>;
ranges;
vdev0vring0: vdev0vring0@90000000 {
reg = <0 0x90000000 0 0x8000>;
no-map;
};
vdev0vring1: vdev0vring1@90008000 {
reg = <0 0x90008000 0 0x8000>;
no-map;
};
vdev1vring0: vdev1vring0@90010000 {
reg = <0 0x90010000 0 0x8000>;
no-map;
};
vdev1vring1: vdev1vring1@90018000 {
reg = <0 0x90018000 0 0x8000>;
no-map;
};
rsc_table: rsc_table@900ff000 {
reg = <0 0x900ff000 0 0x1000>;
no-map;
};
vdevbuffer: vdevbuffer {
compatible = "shared-dma-pool";
reg = <0 0x90400000 0 0x100000>;
no-map;
};
};
rpmsg: rpmsg@0 {
compatible = "fsl,imx8qxp-rpmsg";
reg = <0 0x90000000 0 0x20000>;
mbox-names = "tx", "rx", "rxdb";
mboxes = <&lsio_mu5 0 1
&lsio_mu5 1 1
&lsio_mu5 3 1>;
memory-region = <&vdevbuffer>;
mub-partition = <3>;
vdev-nums = <2>;
};
};
Although I separated the vdev buffers, I don’t think that’s really necessary in this case. But anyways, the missing part was:
memory-region = <&vdevbuffer>;
where we need to tell the driver where is our shared DMA memory.
Now, when I boot the Colibri iMX8X with this overlay enabled, I can see the channel being created:
root@colibri-imx8x-06995602:~# dmesg | grep -i rpmsg
[ 0.314140] imx rpmsg driver is registered.
[ 2.107181] imx-rpmsg 90000000.rpmsg: assigned reserved memory node vdevbuffer
[ 2.120302] virtio_rpmsg_bus virtio0: rpmsg host is online
[ 2.122296] virtio_rpmsg_bus virtio0: creating channel rpmsg-i2c-channel addr 0x1
[ 2.140946] virtio_rpmsg_bus virtio1: rpmsg host is online
[ 2.141067] i2c-rpmsg virtio0.rpmsg-i2c-channel.-1.1: new channel: 0x400 -> 0x1!
[ 2.141130] virtio_rpmsg_bus virtio1: creating channel rpmsg-openamp-demo-channel addr 0x1e
Now I can modprobe the driver:
root@colibri-imx8x-06995602:~# modprobe imx_rpmsg_tty
[ 27.582079] imx_rpmsg_tty virtio1.rpmsg-openamp-demo-channel.-1.30: new channel: 0x400 -> 0x1e!
[ 27.591143] Install rpmsg tty driver!
And it works:
root@colibri-imx8x-06995602:~# echo -n Toradex > /dev/ttyRPMSG30
M4 debug UART:
RPMSG String Echo FreeRTOS RTOS API Demo...
Nameservice sent, ready for incoming messages...
Get Message From Master Side : "hello world!" [len : 12]
Get Message From Master Side : "Toradex" [len : 7]
Get New Line From Master Side
Get Message From Master Side : "Toradex" [len : 7]
Here are my enabled overlays:
root@colibri-imx8x-06995602:~# cat /boot/overlays.txt
fdt_overlays=colibri-imx8x_vga-640x480_overlay.dtbo colibri-imx8x_hmp_overlay.dtbo
And I booted the M4 from the boot partition as well, with u-boot:
Colibri iMX8X # load mmc 0:1 ${loadaddr} rpmsg_lite_str_echo_rtos.bin
67720 bytes read in 6 ms (10.8 MiB/s)
Colibri iMX8X # dcache flush
Colibri iMX8X # bootaux ${loadaddr}
Power on aux core 0
Copy image from 0x95c00000 to 0x34fe0000
Start M4
bootaux complete
Colibri iMX8X # setenv fdt_high 0xffffffffffffffff
Colibri iMX8X #
Colibri iMX8X # saveenv
Saving Environment to MMC... Writing to MMC(0)... OK
Colibri iMX8X # boot
I installed the Multimedia image from our feeds, version 6.3.0-build.7:
root@colibri-imx8x-06995602:~# tdx-info
Software summary
------------------------------------------------------------
Bootloader: U-Boot
Kernel version: 5.15.77-6.3.0+git.ddc6ca4d76ea #1 SMP PREEMPT Thu Jun 29 10:14:22 UTC 2023
Kernel command line: root=PARTUUID=3cccb3bf-02 ro rootwait console=tty1 console=ttyLP3,115200 consoleblank=0 earlycon video=imxdpufb5:off video=imxdpufb6:off video=imxdpufb7:off
Distro name: NAME="TDX Wayland with XWayland"
Distro version: VERSION_ID=6.3.0-build.7
Hostname: colibri-imx8x-06995602
------------------------------------------------------------
Hardware info
------------------------------------------------------------
HW model: Toradex Colibri iMX8QXP on Colibri Evaluation Board V3
Toradex version: 0038 V1.0D
Serial number: 06995602
Processor arch: aarch64
------------------------------------------------------------
Finally, because I’m using the Colibri Development Board, I changed the UART pins in the MCUXpresso M4 code so I could see the debug messages from Cortex-M on pin SODIMM_146:
diff --git a/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.c b/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.c
index 7339c00..391d914 100644
--- a/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.c
+++ b/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.c
@@ -70,12 +70,12 @@ void BOARD_InitPins(sc_ipc_t ipc) /*!< Function assigne
{
assert(false);
}
- err = sc_pad_set_all(ipc, BOARD_INITPINS_M40_UART0_RX_PIN_FUNCTION_ID, 1U, SC_PAD_CONFIG_NORMAL, SC_PAD_ISO_OFF, 0x0 ,SC_PAD_WAKEUP_OFF);/* IOMUXD_ADC_IN2 register modification value */
+ err = sc_pad_set_all(ipc, BOARD_INITPINS_M40_UART0_RX_PIN_FUNCTION_ID, 2U, SC_PAD_CONFIG_NORMAL, SC_PAD_ISO_OFF, 0x0 ,SC_PAD_WAKEUP_OFF);/* IOMUXD_ADC_IN2 register modification value */
if (SC_ERR_NONE != err)
{
assert(false);
}
- err = sc_pad_set_all(ipc, BOARD_INITPINS_M40_UART0_TX_PIN_FUNCTION_ID, 1U, SC_PAD_CONFIG_NORMAL, SC_PAD_ISO_OFF, 0x0 ,SC_PAD_WAKEUP_OFF);/* IOMUXD_ADC_IN3 register modification value */
+ err = sc_pad_set_all(ipc, BOARD_INITPINS_M40_UART0_TX_PIN_FUNCTION_ID, 2U, SC_PAD_CONFIG_NORMAL, SC_PAD_ISO_OFF, 0x0 ,SC_PAD_WAKEUP_OFF);/* IOMUXD_ADC_IN3 register modification value */
if (SC_ERR_NONE != err)
{
assert(false);
diff --git a/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.h b/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.h
index 900d8ef..b76b299 100644
--- a/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.h
+++ b/boards/mekmimx8qx/multicore_examples/rpmsg_lite_str_echo_rtos/pin_mux.h
@@ -14,10 +14,10 @@
**********************************************************************************************************************/
/* ADC_IN2 (coord V32), M40_UART0_RX */
-#define BOARD_INITPINS_M40_UART0_RX_PIN_FUNCTION_ID SC_P_ADC_IN2 /*!< Pin function id */
+#define BOARD_INITPINS_M40_UART0_RX_PIN_FUNCTION_ID SC_P_SCU_GPIO0_00 /*!< Pin function id */
/* ADC_IN3 (coord V30), M40_UART0_TX */
-#define BOARD_INITPINS_M40_UART0_TX_PIN_FUNCTION_ID SC_P_ADC_IN3 /*!< Pin function id */
+#define BOARD_INITPINS_M40_UART0_TX_PIN_FUNCTION_ID SC_P_SCU_GPIO0_01 /*!< Pin function id */
/* ADC_IN0 (coord U35), M4_I2C0_1V8_SCL */
#define BOARD_INITPINS_M4_I2C0_1V8_SCL_PIN_FUNCTION_ID SC_P_ADC_IN0 /*!< Pin function id */
I did this because we don’t have access to the default pins from MCUXpresso.
if you want to try it yourself, here is the compiled overlay: https://share.toradex.com/5bim7bz2bnqaudc (it will be available for 3 months).
Let me know if you have any questions!
Best Regards,
Hiago.