How does one run the sai_low_power_audio.bin example via U-boot?

mwilliams — Fri, 21 Oct 2022 13:48:42 GMT

I am looking for help to run the sai_low_power_audio.bin example. So far I have loaded the example in the TCM and set the DTB as follows:

u-boot=> fatload mmc 1:1 0x48000000 sai_low_power_audio.bin
42744 bytes read in 5 ms (8.2 MiB/s)
u-boot=> cp.b 0x48000000 0x7e0000 0x20000
u-boot=> bootaux 0x7e0000
## Starting auxiliary core stack = 0x20020000, pc = 0x1FFE031D...
u-boot=> setenv fdtfile 'fsl-imx8mm-evk-m4.dtb'

I see the output on the M4 console that shows the example has started:

Now I need to start linux, how is that done properly?

My fist attempt results in the following:

u-boot=> boot
starting USB...
Bus usb@32e40000: Port not available.
USB is stopped. Please issue 'usb start' first.
switch to partitions #0, OK
mmc1 is current device
Scanning mmc 1:1...
libfdt fdt_check_header(): FDT_ERR_BADMAGIC
Scanning disk mmc@30b50000.blk...
Scanning disk mmc@30b60000.blk...
Found 6 disks
Unable to open OP-TEE session (err=-5)
mm_communicate failed!
Error: Cannot initialize UEFI sub-system, r = 3
switch to partitions #0, OK
mmc2(part 0) is current device
Scanning mmc 2:1...
libfdt fdt_check_header(): FDT_ERR_BADMAGIC
Error: Cannot initialize UEFI sub-system, r = 3
Running BSP bootcmd ...
switch to partitions #0, OK
mmc1 is current device
Failed to load 'boot.scr'
30931456 bytes read in 1761 ms (16.8 MiB/s)
Booting from mmc ...
Failed to load 'fsl-imx8mm-evk-m4.dtb'
WARN: Cannot load the DT

Thanks in advance.

Re: How does one run the sai_low_power_audio.bin example via U-boot?

mwilliams — Fri, 21 Oct 2022 13:56:45 GMT

I had the wrong dtb file, the correct file is imx8mm-evk-rpmsg.dtb.

Now when booting linux I see:

#################### LOW POWER AUDIO TASK ####################

Build Time: Oct 21 2022--08:13:27
********************************
Wait the Linux kernel boot up to create the link between M core and A core.

********************************
The rpmsg channel between M core and A core created!
********************************

Task A is working now.

No audio playback, M core enters STOP mode!

topic How does one run the sai_low_power_audio.bin example via U-boot? in i.MX Processors

How does one run the sai_low_power_audio.bin example via U-boot?

Re: How does one run the sai_low_power_audio.bin example via U-boot?