Hi @majd.m
Sorry for the delayed answer. I tried this today too.
I got the following error and there is no rpmsg_char device.
[ 0.056564] MU is ready for cross core communication!
[ 0.056701] ------------[ cut here ]------------
[ 0.056734] WARNING: CPU: 0 PID: 1 at arch/arm/mm/ioremap.c:303 __arm_ioremap_pfn_caller+0xd8/0x1b4
[ 0.056756] Modules linked in:
[ 0.056779] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.117 #1
[ 0.056796] Hardware name: Freescale i.MX7 Dual (Device Tree)
[ 0.056834] [<8010e4c0>] (unwind_backtrace) from [<8010afdc>] (show_stack+0x10/0x14)
[ 0.056866] [<8010afdc>] (show_stack) from [<807efba4>] (dump_stack+0x88/0x9c)
[ 0.056898] [<807efba4>] (dump_stack) from [<80123a14>] (__warn+0xe8/0x100)
[ 0.056926] [<80123a14>] (__warn) from [<80123adc>] (warn_slowpath_null+0x20/0x28)
[ 0.056956] [<80123adc>] (warn_slowpath_null) from [<801144f4>] (__arm_ioremap_pfn_caller+0xd8/0x1b4)
[ 0.056986] [<801144f4>] (__arm_ioremap_pfn_caller) from [<8011461c>] (__arm_ioremap_caller+0x4c/0x54)
[ 0.057018] [<8011461c>] (__arm_ioremap_caller) from [<80643e20>] (imx_rpmsg_find_vqs+0xb4/0x214)
[ 0.057048] [<80643e20>] (imx_rpmsg_find_vqs) from [<80643224>] (rpmsg_probe+0xc8/0x4b4)
[ 0.057078] [<80643224>] (rpmsg_probe) from [<8049d394>] (virtio_dev_probe+0x1f0/0x2cc)
[ 0.057112] [<8049d394>] (virtio_dev_probe) from [<804d5950>] (driver_probe_device+0x210/0x2dc)
[ 0.057145] [<804d5950>] (driver_probe_device) from [<804d3f74>] (bus_for_each_drv+0x44/0x94)
[ 0.057177] [<804d3f74>] (bus_for_each_drv) from [<804d5660>] (__device_attach+0xb0/0x114)
[ 0.057207] [<804d5660>] (__device_attach) from [<804d4c4c>] (bus_probe_device+0x84/0x8c)
[ 0.057237] [<804d4c4c>] (bus_probe_device) from [<804d3098>] (device_add+0x3b0/0x5a0)
[ 0.057266] [<804d3098>] (device_add) from [<8049cef8>] (register_virtio_device+0xd8/0xf0)
[ 0.057295] [<8049cef8>] (register_virtio_device) from [<806444ec>] (imx_rpmsg_probe+0x310/0x528)
[ 0.057324] [<806444ec>] (imx_rpmsg_probe) from [<804d7164>] (platform_drv_probe+0x50/0xac)
[ 0.057355] [<804d7164>] (platform_drv_probe) from [<804d5950>] (driver_probe_device+0x210/0x2dc)
[ 0.057387] [<804d5950>] (driver_probe_device) from [<804d5ac0>] (__driver_attach+0xa4/0xa8)
[ 0.057417] [<804d5ac0>] (__driver_attach) from [<804d3ecc>] (bus_for_each_dev+0x4c/0x9c)
[ 0.057448] [<804d3ecc>] (bus_for_each_dev) from [<804d4ed4>] (bus_add_driver+0x188/0x20c)
[ 0.057478] [<804d4ed4>] (bus_add_driver) from [<804d6380>] (driver_register+0x78/0xf4)
[ 0.057511] [<804d6380>] (driver_register) from [<80c2b668>] (imx_rpmsg_init+0x10/0x34)
[ 0.057541] [<80c2b668>] (imx_rpmsg_init) from [<801019f0>] (do_one_initcall+0x44/0x168)
[ 0.057572] [<801019f0>] (do_one_initcall) from [<80c00d9c>] (kernel_init_freeable+0x148/0x1d4)
[ 0.057604] [<80c00d9c>] (kernel_init_freeable) from [<80801d40>] (kernel_init+0x8/0x10c)
[ 0.057636] [<80801d40>] (kernel_init) from [<80107728>] (ret_from_fork+0x14/0x2c)
[ 0.057666] ---[ end trace d21ae44de27e64ed ]---
[ 0.057703] virtio_rpmsg_bus: probe of virtio0 failed with error -12
[ 0.057890] imx rpmsg driver is registered.
[ 0.058756] MU is ready for cross core communication!
We have to analyse this further and we will come back to you.
Best regards,
Jaski