Commit e39bf297 authored Dec 15, 2021 by Shawn Guo Committed by Georgi Djakov Dec 15, 2021

interconnect: icc-rpm: Support child NoC device probe

As shown in downstream DT[1], the System NoC of QCM2290 is modelled
using 4 fab/noc devices: sys_noc + qup_virt + mmnrt_virt + mmrt_virt.
Among those 3 virtual devices, qup is owned by RPM and has no regmap
resource, while mmnrt and mmrt are owned by AP and share the same
regmap as sys_noc.  So it's logical to represent these virtual devices
as child nodes of sys_noc in DT, so that such configuration can be
supported with a couple of changes on qnoc_probe():

- If there are child nodes, populate them.
- If the device descriptor has .regmap_cfg but there is no IOMEM
  resource for the device, use parent's regmap.

[1] https://android.googlesource.com/kernel/msm-extra/devicetree/+/refs/tags/android-11.0.0_r0.56/qcom/scuba-bus.dtsi



Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20211215002324.1727-4-shawn.guo@linaro.org


Signed-off-by: Georgi Djakov <djakov@kernel.org>

parent 08c59040

drivers/interconnect/qcom/icc-rpm.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -349,8 +349,13 @@ int qnoc_probe(struct platform_device *pdev)
		void __iomem *mmio;

		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
		if (!res)
		if (!res) {
		/* Try parent's regmap */
		qp->regmap = dev_get_regmap(dev->parent, NULL);
		if (qp->regmap)
		goto regmap_done;
		return -ENODEV;
		}

		mmio = devm_ioremap_resource(dev, res);

		@@ -366,6 +371,7 @@ int qnoc_probe(struct platform_device *pdev)
		}
		}

		regmap_done:
		ret = devm_clk_bulk_get(dev, qp->num_clks, qp->bus_clks);
		if (ret)
		return ret;
		@@ -417,6 +423,10 @@ int qnoc_probe(struct platform_device *pdev)

		platform_set_drvdata(pdev, qp);

		/* Populate child NoC devices if any */
		if (of_get_child_count(dev->of_node) > 0)
		return of_platform_populate(dev->of_node, NULL, NULL, dev);

		return 0;
		err:
		icc_nodes_remove(provider);