nRF5340 BLE DFU from NET core

[valeriy_simakov]

Hello! 
Introduction. Responsibilities of the cores in my device:
1. app core. 
1.1. data processing from a stereo microphone
1.2. data sending to net core.
2. net core. 
2.1. ble communication, services supporting. 
2.2. data receiving from app core.

Everything works fine :)
But now I want to add BLE DFU )

As I understood from examples, I should use app core for smp server, so I should use ble communication support on app core, which changes my whole architecture.

Could please anyone help me with that situation? :)

[Sigurd Hellesvik]

Hi,

What you want to do is not the standard way to do stuff, so it is not supported or tested.

However, it can be done.

First, tell me: Do you want to update both cores?

How large is your network core application?

Regards,
Sigurd Hellesvik

[valeriy_simakov]

For both cores:

[192/196] Linking CXX executable zephyr\cpuapp.elf
Memory region    Used Size      Region Size   %age Used
FLASH:               85552 B         1 MB              8.16%
RAM:                  399824 B        448 KB          87.15%
IDT_LIST:           0 GB               2 KB              0.00%

[210/210] Linking C executable zephyr\cpunet.elf
Memory region    Used Size       Region Size  %age Used
FLASH:               254588 B        256 KB          97.12%
RAM:                  56096 B           64 KB           85.60%
SRAM1:              0 GB                64 KB           0.00%
IDT_LIST:            0 GB               2 KB              0.00%

[valeriy_simakov]

Hi Sigurd Hellesvik 
Well, I'm stuck on the "wrapper of smp service" on the app core side. I couldn't find an example of DFU Target usage in my sdk. 
Now I'm trying to use the "common way". I'm worried about BLE speed, because now I use BLE stack on the app core. But as I understand physically, net core will send the final data, am I right?

[valeriy_simakov]

I mean, does the app core use the ble api via rpmsg in net core ? Аnd all the ble stack is contained in the network core.

[valeriy_simakov]

Bad news. I can't get the same speed of data transfer. 

Fullscreen 154_ota_ver2_speed_test_9sec_no_copy_first_fast.txt Download

00> [00:01:19.984,344] <inf> app: do_pdm_transfer: PCM output rate: 16000, channels: 2
00> [00:01:19.984,375] <inf> app: sender_clear: Cleanup sender, before:
00> [00:01:19.984,375] <inf> app: sender_clear: Cashed slab num free 60
00> [00:01:19.984,405] <inf> app: sender_clear: Sender slab num free 10
00> [00:01:19.984,436] <inf> app: sender_clear: Cleanup sender, after:
00> [00:01:19.984,436] <inf> app: sender_clear: Cashed slab num free 60
00> [00:01:19.984,466] <inf> app: sender_clear: Sender slab num free 10
00> [00:01:19.984,497] <inf> app: do_pdm_transfer: Expected amount of data, bytes: 576000
00> [00:01:20.085,662] <inf> cpu_net: slab_notify: New packet, number: 1, payload size: 487, packet size: 495
00> --- 13 messages dropped ---
00> [00:01:20.085,784] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 974
00> [00:01:20.085,876] <inf> cpu_net: slab_notify: New packet, number: 2, payload size: 487, packet size: 495
00> [00:01:20.085,998] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 1461
00> [00:01:20.086,090] <inf> cpu_net: slab_notify: New packet, number: 3, payload size: 487, packet size: 495
00> [00:01:20.086,212] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 1948
00> [00:01:20.086,303] <inf> cpu_net: slab_notify: New packet, number: 4, payload size: 487, packet size: 495
00> [00:01:20.086,425] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 2435
00> [00:01:20.086,517] <inf> cpu_net: slab_notify: New packet, number: 5, payload size: 487, packet size: 495
00> [00:01:20.086,639] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 2922
00> [00:01:20.086,730] <inf> cpu_net: slab_notify: New packet, number: 6, payload size: 487, packet size: 495
00> [00:01:20.086,853] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 3409
00> [00:01:20.086,944] <inf> cpu_net: slab_notify: New packet, number: 7, payload size: 487, packet size: 495
00> [00:01:20.087,066] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 3896
00> [00:01:20.087,158] <inf> cpu_net: slab_notify: New packet, number: 8, payload size: 487, packet size: 495
00> [00:01:20.087,310] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 4383
00> [00:01:20.087,402] <inf> cpu_net: slab_notify: New packet, number: 9, payload size: 487, packet size: 495
00> [00:01:20.087,524] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 4870
00> [00:01:20.087,646] <inf> cpu_net: slab_notify: New packet, number: 10, payload size: 487, packet size: 495
00> [00:01:20.087,768] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 5357
00> [00:01:20.087,860] <inf> cpu_net: slab_notify: New packet, number: 11, payload size: 487, packet size: 495
00> [00:01:20.087,982] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 5844
00> [00:01:20.088,104] <inf> cpu_net: slab_notify: New packet, number: 12, payload size: 487, packet size: 495
00> [00:01:20.088,226] <inf> cpu_net: slab_notify: Payload size to send: 69, sent: 6331
00> [00:01:20.088,256] <inf> cpu_net: slab_notify: New packet, number: 13, payload size: 69, packet size: 77
00> [00:01:20.188,415] <inf> cpu_net: slab_notify: New slab: 0x2007e100
00> [00:01:20.188,446] <inf> cpu_net: slab_notify: New slab index: 1
00> [00:01:20.188,476] <inf> cpu_net: slab_notify: Current MTU: 498
00> [00:01:20.188,476] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 0
00> [00:01:20.188,568] <inf> cpu_net: slab_notify: New packet, number: 14, payload size: 487, packet size: 495
00> [00:01:20.188,690] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 487
00> [00:01:20.188,812] <inf> cpu_net: slab_notify: New packet, number: 15, payload size: 487, packet size: 495
00> [00:01:20.188,903] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 974
00> [00:01:20.189,025] <inf> cpu_net: slab_notify: New packet, number: 16, payload size: 487, packet size: 495
00> [00:01:20.189,147] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 1461
00> [00:01:20.189,239] <inf> cpu_net: slab_notify: New packet, number: 17, payload size: 487, packet size: 495
00> [00:01:20.189,361] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 1948
00> [00:01:20.189,453] <inf> cpu_net: slab_notify: New packet, number: 18, payload size: 487, packet size: 495
00> [00:01:20.189,575] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 2435
00> [00:01:20.189,666] <inf> cpu_net: slab_notify: New packet, number: 19, payload size: 487, packet size: 495
00> [00:01:20.189,788] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 2922
00> [00:01:20.189,880] <inf> cpu_net: slab_notify: New packet, number: 20, payload size: 487, packet size: 495
00> [00:01:20.673,980] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 3409
00> [00:01:20.674,102] <inf> cpu_net: slab_notify: New packet, number: 21, payload size: 487, packet size: 495
00> [00:01:21.274,810] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 3896
00> [00:01:21.274,902] <inf> cpu_net: slab_notify: New packet, number: 22, payload size: 487, packet size: 495
00> [00:01:21.873,962] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 4383
00> [00:01:21.874,084] <inf> cpu_net: slab_notify: New packet, number: 23, payload size: 487, packet size: 495
00> [00:01:22.474,822] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 4870
00> [00:01:22.474,914] <inf> cpu_net: slab_notify: New packet, number: 24, payload size: 487, packet size: 495
00> [00:01:23.133,972] <inf> cpu_net: slab_notify: Payload size to send: 495, sent: 5357
00> [00:01:23.134,063] <inf> cpu_net: slab_notify: New packet, number: 25, payload size: 487, packet size: 495
00> [00:01:23.674,591] <inf> settings_service: WriteRecEnableFlag: New value of record enable flag 0
00> [00:01:23.674,621] <inf> cpu_net: signal_settings_notify: Send settings to App
00> [00:01:23.674,621] <inf> cpu_net: signal_settings_notify: Record duration, sec: 9
00> [00:01:23.674,652] <inf> cpu_net: signal_settings_notify: Record enable flag, value: 0

1 slab = 6400B.
The first slab is sent quickly, then the speed starts to drop.

I use bt_gatt_notify() api. 

How can I improve my performance?

[Sigurd Hellesvik]

There is a little while since last time I looked at this ticket. One thing is unclear to me now when I look over it again, so could you referesh my memory:

Do you use RPC for this?

[valeriy_simakov]

In my initial architecture, I use:

1. mbox_channel

2. shared memory
3. my binary for net core with BLE processing and main logic on app core. 

But I'm stuck with OTA implementation. 

Now I use "common way" architecture and write code in app core. 
And use BLE API in app core, like bt_gatt_notify e.t.c. 

[Sigurd Hellesvik]

With the "common way", you should be able to get quite good transfer speeds.

Here is from the solution sample for Simultaneous updates for both cores of the nRF5340:

As you can see, I get 14kB/s transfer rates.

Do these speeds match what you need?