interconnect: qcom: rpm: make QoS INVALID default

Currently NOC_QOS_MODE_FIXED is defined as 0x0 which makes it the
default option (partial struct initialization). The default option
however should be NOC_QOS_MODE_INVALID.

That results in bogus QoS configurations being sent for port 0 (which
is used for the DRAM endpoint on BIMC, for example) coming from all nodes
with .qos.ap_owned = true and uninitialized .qos.qos_mode. It's also an
issue for newer SoCs where all nodes are treated as if they were ap_owned,
but not all of them have QoS configuration.

The NOC_QOS_MODEs are defined as preprocessor constants and are not used
anywhere outside qcom_icc_set_noc_qos(), which is easily worked around.
Separate the desc->type values from the values sent to msmbus in the
aforementioned function. Make the former an enum for better mainainability.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230228-topic-qos-v7-1-815606092fff@linaro.orgSigned-off-by: Georgi Djakov <djakov@kernel.org>

drivers/interconnect/qcom/icc-rpm.c

@@ -47,6 +47,9 @@
 #define NOC_QOS_MODEn_ADDR(n)		(0xc + (n * 0x1000))
 #define NOC_QOS_MODEn_MASK		0x3
 
+#define NOC_QOS_MODE_FIXED_VAL		0x0
+#define NOC_QOS_MODE_BYPASS_VAL		0x2
+
 static int qcom_icc_set_qnoc_qos(struct icc_node *src, u64 max_bw)
 {
 	struct icc_provider *provider = src->provider;
@@ -152,7 +155,7 @@ static int qcom_icc_set_noc_qos(struct icc_node *src, u64 max_bw)
 	struct qcom_icc_provider *qp;
 	struct qcom_icc_node *qn;
 	struct icc_provider *provider;
-	u32 mode = NOC_QOS_MODE_BYPASS;
+	u32 mode = NOC_QOS_MODE_BYPASS_VAL;
 	int rc = 0;
 
 	qn = src->data;
@@ -166,18 +169,17 @@ static int qcom_icc_set_noc_qos(struct icc_node *src, u64 max_bw)
 		return 0;
 	}
 
-	if (qn->qos.qos_mode != NOC_QOS_MODE_INVALID)
-		mode = qn->qos.qos_mode;
-
-	if (mode == NOC_QOS_MODE_FIXED) {
-		dev_dbg(src->provider->dev, "NoC QoS: %s: Set Fixed mode\n",
-			qn->name);
+	if (qn->qos.qos_mode == NOC_QOS_MODE_FIXED) {
+		dev_dbg(src->provider->dev, "NoC QoS: %s: Set Fixed mode\n", qn->name);
+		mode = NOC_QOS_MODE_FIXED_VAL;
 		rc = qcom_icc_noc_set_qos_priority(qp, &qn->qos);
 		if (rc)
 			return rc;
-	} else if (mode == NOC_QOS_MODE_BYPASS) {
-		dev_dbg(src->provider->dev, "NoC QoS: %s: Set Bypass mode\n",
-			qn->name);
+	} else if (qn->qos.qos_mode == NOC_QOS_MODE_BYPASS) {
+		dev_dbg(src->provider->dev, "NoC QoS: %s: Set Bypass mode\n", qn->name);
+		mode = NOC_QOS_MODE_BYPASS_VAL;
+	} else {
+		/* How did we get here? */
 	}
 
 	return regmap_update_bits(qp->regmap,
@@ -243,7 +245,7 @@ static int __qcom_icc_set(struct icc_node *n, struct qcom_icc_node *qn,
 		ret = qcom_icc_rpm_set(qn->mas_rpm_id, qn->slv_rpm_id, sum_bw);
 		if (ret)
 			return ret;
-	} else if (qn->qos.qos_mode != -1) {
+	} else if (qn->qos.qos_mode != NOC_QOS_MODE_INVALID) {
 		/* set bandwidth directly from the AP */
 		ret = qcom_icc_qos_set(n, sum_bw);
 		if (ret)

drivers/interconnect/qcom/icc-rpm.h

@@ -96,10 +96,12 @@ struct qcom_icc_desc {
 	unsigned int qos_offset;
 };
 
-/* Valid for both NoC and BIMC */
-#define NOC_QOS_MODE_INVALID		-1
-#define NOC_QOS_MODE_FIXED		0x0
-#define NOC_QOS_MODE_BYPASS		0x2
+/* Valid for all bus types */
+enum qos_mode {
+	NOC_QOS_MODE_INVALID = 0,
+	NOC_QOS_MODE_FIXED,
+	NOC_QOS_MODE_BYPASS,
+};
 
 int qnoc_probe(struct platform_device *pdev);
 int qnoc_remove(struct platform_device *pdev);