On 11/30/2024 9:02 PM, Dmitry Baryshkov wrote: > On Sat, Nov 30, 2024 at 04:12:49PM +0100, Konrad Dybcio wrote: >> On 30.11.2024 4:09 PM, Dmitry Baryshkov wrote: >>> On Sat, Nov 30, 2024 at 01:49:56PM +0100, Konrad Dybcio wrote: >>>> On 25.11.2024 6:45 PM, Raviteja Laggyshetty wrote: >>>>> EPSS on SA8775P has two instances which requires creation of two device >>>>> nodes with different compatible and device data because of unique >>>>> icc node id and name limitation in interconnect framework. >>>>> Add multidevice support to osm-l3 code to get unique node id from IDA >>>>> and node name is made unique by appending node address. >>>>> >>>>> Signed-off-by: Raviteja Laggyshetty <quic_rlaggysh@xxxxxxxxxxx> >>>>> --- >>>> >>>> [...] >>>> >>>>> + ret = of_property_read_reg(pdev->dev.of_node, 0, &addr, NULL); >>>>> + if (ret) >>>>> + return ret; >>>>> + >>>>> qp->base = devm_platform_ioremap_resource(pdev, 0); >>>>> if (IS_ERR(qp->base)) >>>>> return PTR_ERR(qp->base); >>>>> @@ -242,8 +262,13 @@ static int qcom_osm_l3_probe(struct platform_device *pdev) >>>>> >>>>> icc_provider_init(provider); >>>>> >>>>> + /* Allocate unique id for qnodes */ >>>>> + for (i = 0; i < num_nodes; i++) >>>>> + qnodes[i]->id = ida_alloc_min(&osm_l3_id, OSM_L3_NODE_ID_START, GFP_KERNEL); >>>> >>>> As I've said in my previous emails, this is a framework-level problem. >>>> >>>> Up until now we've simply silently ignored the possibility of an >>>> interconnect provider having more than one instance, as conveniently >>>> most previous SoCs had a bunch of distinct bus masters. >>>> >>>> Currently, debugfs-client.c relies on the node names being unique. >>>> Keeping them as such is also useful for having a sane sysfs/debugfs >>>> interface. But it's not always feasible, and a hierarchical approach >>>> (like in pmdomain) may be a better fit. >>>> >>>> Then, node->id is used for creating links, and we unfortunately cannot >>>> assume that both src and dst are within the same provider. >>>> I'm not a fan of these IDs being hardcoded, but there are some drivers >>>> that rely on that, which itself is also a bit unfortunate.. >>>> >>>> >>>> If Mike (who introduced debugfs-client and is probably the main user) >>>> doesn't object to a small ABI break (which is "fine" with a debugfs >>>> driver that requires editing the source code to be compiled), we could >>>> add a property within icc_provider like `bool dynamic_ids` and have an >>>> ICC-global IDA that would take care of any conflicts. >>> >>> Frankly speaking, I think this just delays the inevitable. We have been >>> there with GPIOs and with some other suppliers. In my opinion the ICC >>> subsystem needs to be refactored in order to support linking based on >>> the supplier (fwnode?) + offset_id, but that's a huuuge rework. >> >> I thought about this too, but ended up not including it in the email.. >> >> I think this will be more difficult with ICC, as tons of circular >> dependencies are inevitable by design and we'd essentially have to >> either provide placeholder nodes (like it's the case today) or probe >> only parts of a device, recursively, to make sure all links can be >> created > > Or just allow probing, but then fail path creation. It will be a > redesign, but I think it is inevitable in the end. > There are no two instances of l3 or NoC on any SoC except qcs9100 and qcs8300. I dont expect any new SoC as well. As second instance is needed only on qcs9100 and qcs8300, I am keeping the patch (patchset v6) as is and limit the dynamic id addition to l3 provider only. >> >> Konrad >> >>>> Provider drivers whose consumers don't already rely on programmatical >>>> use of hardcoded IDs *and* don't have cross-provider links could then >>>> enable that flag and have the node IDs and names set like you did in >>>> this patch. This also sounds very useful for icc-clk. >>> >
