I don't know what kind of RPMSG patch you need, this link is for wake up A core and M core, if you need any other patch pls share more detailed information, but this patch is for 4.14, for 5.10 bsp, you need change it according to the document, if you need other kind of usage, pls let me know it
if you just need normal rpmsg testing, don't need any patch for it pls refer to the chapter 2.8 Remote Processor Messaging of enclosed file which gives you detailed test steps
pls refer to the document I sent to you, in linux side, you can find rpmsg test under unit test folder, the detailed command, pls refer to the document I sent to you before
