interconnect: qcom: Fix DT backwards compatibility for QoS

Add qos_clks_required flag to skip QoS configuration if clocks property
is not populated in devicetree for providers which require clocks to be
enabled for accessing registers. This is to keep the QoS configuration
backwards compatible with devices that have older DTB.

Reported-by: Bjorn Andersson <[email protected]>
Closes: https://lore.kernel.org/all/ciji6nlxn752ina4tmh6kwvek52nxpnguomqek6plwvwgvoqef@yrtexkpmn5br/
Signed-off-by: Odelu Kukatla <[email protected]>
Tested-by: Bjorn Andersson <[email protected]>
Fixes: fbd908b ("interconnect: qcom: sc7280: enable QoS configuration")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Georgi Djakov <[email protected]>

Author: Odelu Kukatla

drivers/interconnect/qcom/icc-rpmh.c

@@ -311,7 +311,7 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
 		}
 
 		qp->num_clks = devm_clk_bulk_get_all(qp->dev, &qp->clks);
-		if (qp->num_clks < 0) {
+		if (qp->num_clks < 0 || (!qp->num_clks && desc->qos_clks_required)) {
 			dev_info(dev, "Skipping QoS, failed to get clk: %d\n", qp->num_clks);
 			goto skip_qos_config;
 		}

drivers/interconnect/qcom/icc-rpmh.h

@@ -153,6 +153,7 @@ struct qcom_icc_desc {
 	size_t num_nodes;
 	struct qcom_icc_bcm * const *bcms;
 	size_t num_bcms;
+	bool qos_clks_required;
 };
 
 int qcom_icc_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,

drivers/interconnect/qcom/sc7280.c

@@ -1691,6 +1691,7 @@ static const struct qcom_icc_desc sc7280_aggre1_noc = {
 	.num_nodes = ARRAY_SIZE(aggre1_noc_nodes),
 	.bcms = aggre1_noc_bcms,
 	.num_bcms = ARRAY_SIZE(aggre1_noc_bcms),
+	.qos_clks_required = true,
 };
 
 static struct qcom_icc_bcm * const aggre2_noc_bcms[] = {
@@ -1722,6 +1723,7 @@ static const struct qcom_icc_desc sc7280_aggre2_noc = {
 	.num_nodes = ARRAY_SIZE(aggre2_noc_nodes),
 	.bcms = aggre2_noc_bcms,
 	.num_bcms = ARRAY_SIZE(aggre2_noc_bcms),
+	.qos_clks_required = true,
 };
 
 static struct qcom_icc_bcm * const clk_virt_bcms[] = {