On 29/07/25 6:02 pm, Krzysztof Kozlowski wrote: > On 29/07/2025 11:46, MD Danish Anwar wrote: >>>> >>>> One idea I had was to create a new binding for this node, and use >>>> compatible string to access the node in driver. But the device is >>>> virtual and not physical so I thought that might not be the way to go so >>>> I went with the current approach. >>> >>> virtual devices do not go to DTS anyway. How do you imagine this works? >>> You add it to DTS but you do not add bindings and you expect checks to >>> succeed? >>> >>> Provide details how you checked your DTS compliance. >>> >>> >> >> This is my device tree patch [1]. I ran these two commands before and >> after applying the patch and checked the diff. >> >> make dt_binding_check >> make dtbs_check >> >> I didn't see any new error / warning getting introduced due to the patch >> >> After applying the patch I also ran, >> >> make CHECK_DTBS=y ti/k3-am642-evm.dtb >> >> I still don't see any warnings / error. >> >> >> If you look at the DT patch, you'll see I am adding a new node in the > > I see. This is so odd syntax... You have the phandle there, so you do > not need to do any node name checking. I did not really expect you will > be checking node name for reserved memory!!! > I don't have access to the phandle in my function. The reserved memory is reserved by ti_k3_r5_remoteproc driver. That driver has the phandle. I am writing a new driver rpmsg_eth, this driver only has the rpdev structure. This driver doesn't have any dt node or phandle and because of this I am doing `peer = of_find_node_by_name(NULL, "virtual-eth-shm");` to get the access to this node here. I couldn't find any way to access the dt node of reserved memory from this (rpmsg_eth) driver. Please let me know if there is any way I can access that. > Obviously this will be fine with dt bindings, because such ABI should > never be constructed. > > >> `reserved-memory`. I am not creating a completely new undocumented node. >> Instead I am creating a new node under reserved-memory as the shared >> memory used by rpmsg-eth driver needs to be reserved first. This memory >> is reserved by the ti_k3_r5_remoteproc driver by k3_reserved_mem_init(). >> >> It's just that I am naming this node as "virtual-eth-shm@a0400000" and >> then using the same name in driver to get the base_address and size >> mentioned in this node. > > And how your driver will work with: > > s/virtual-eth-shm@a0400000/whatever@a0400000/ > It won't. The driver imposes a restriction with the node name. The node name should always be "virtual-eth-shm" For other vendors who want to use this driver, they need to reserve memory for their shared block and name the node `virtual-eth-shm@XXXXXXXX` > ? It will not. > > Best regards, > Krzysztof -- Thanks and Regards, Danish
