[PATCH v4 08/13] EDAC/synopsys: Add individual named ECC IRQs support

[Serge Semin <fancer.lancer@gmail.com>]

Currently the DW uMCTL2 DDRC EDAC driver supports a common unnamed IRQ
only. It isn't suitable for the platforms which have the individual IRQ
lines for each DDRC event (ECC UE, ECC CE, DFI parity error, Scrubber
done, etc). Moreover the DW uMCTL2 DDRC IP-core doesn't have an option to
be configured with a common interrupts output line. So in order to have
the generic DW uMCTL2 DDR controller supported by the driver add the
individual (per DDRC event) IRQs request support.

There is not much to do really since the common IRQs handler has already
been split up into the sub-handlers: first try to request the individual
IRQs; if failed fallback to using the common IRQ. The IRQ names are used
in accordance with the DW uMCTL2 DDRC DT-bindings.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
---
 drivers/edac/synopsys_edac.c | 91 ++++++++++++++++++++++++++++++++----
 1 file changed, 81 insertions(+), 10 deletions(-)

diff --git a/drivers/edac/synopsys_edac.c b/drivers/edac/synopsys_edac.c
index 9dde43636199..19b7bce06e13 100644
--- a/drivers/edac/synopsys_edac.c
+++ b/drivers/edac/synopsys_edac.c
@@ -1533,25 +1533,96 @@ static void snps_mc_free(struct mem_ctl_info *mci)
 	edac_mc_free(mci);
 }
 
-static int snps_setup_irq(struct mem_ctl_info *mci)
+/**
+ * snps_request_ind_irq - Request individual DDRC IRQs.
+ * @mci:	EDAC memory controller instance.
+ *
+ * Return: 0 if the IRQs were successfully requested, 1 if the individual IRQs
+ * are unavailable, otherwise negative errno.
+ */
+static int snps_request_ind_irq(struct mem_ctl_info *mci)
 {
 	struct snps_edac_priv *priv = mci->pvt_info;
-	int ret, irq;
+	struct device *dev = &priv->pdev->dev;
+	int rc, irq;
 
-	irq = platform_get_irq(priv->pdev, 0);
-	if (irq < 0) {
-		edac_printk(KERN_ERR, EDAC_MC,
-			    "No IRQ %d in DT\n", irq);
+	irq = platform_get_irq_byname_optional(priv->pdev, "ecc_ce");
+	if (irq == -ENXIO)
+		return 1;
+	if (irq < 0)
+		return irq;
+
+	rc = devm_request_irq(dev, irq, snps_ce_irq_handler, 0, "ecc_ce", mci);
+	if (rc) {
+		edac_printk(KERN_ERR, EDAC_MC, "Failed to request ECC CE IRQ\n");
+		return rc;
+	}
+
+	irq = platform_get_irq_byname(priv->pdev, "ecc_ue");
+	if (irq < 0)
 		return irq;
+
+	rc = devm_request_irq(dev, irq, snps_ue_irq_handler, 0, "ecc_ue", mci);
+	if (rc) {
+		edac_printk(KERN_ERR, EDAC_MC, "Failed to request ECC UE IRQ\n");
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * snps_request_com_irq - Request common DDRC IRQ.
+ * @mci:	EDAC memory controller instance.
+ *
+ * It first attempts to get the named IRQ. If failed the method fallbacks
+ * to first available one.
+ *
+ * Return: 0 if the IRQ was successfully requested otherwise negative errno.
+ */
+static int snps_request_com_irq(struct mem_ctl_info *mci)
+{
+	struct snps_edac_priv *priv = mci->pvt_info;
+	struct device *dev = &priv->pdev->dev;
+	int rc, irq;
+
+	irq = platform_get_irq_byname_optional(priv->pdev, "ecc");
+	if (irq < 0) {
+		irq = platform_get_irq(priv->pdev, 0);
+		if (irq < 0)
+			return irq;
 	}
 
-	ret = devm_request_irq(&priv->pdev->dev, irq, snps_com_irq_handler,
-			       0, dev_name(&priv->pdev->dev), mci);
-	if (ret < 0) {
+	rc = devm_request_irq(dev, irq, snps_com_irq_handler, 0, "ecc", mci);
+	if (rc) {
 		edac_printk(KERN_ERR, EDAC_MC, "Failed to request IRQ\n");
-		return ret;
+		return rc;
 	}
 
+	return 0;
+}
+
+/**
+ * snps_setup_irq - Request and enable DDRC IRQs.
+ * @mci:	EDAC memory controller instance.
+ *
+ * It first tries to get and request individual IRQs. If failed the method
+ * fallbacks to the common IRQ line case. The IRQs will be enabled only if
+ * some of these requests have been successful.
+ *
+ * Return: 0 if IRQs were successfully setup otherwise negative errno.
+ */
+static int snps_setup_irq(struct mem_ctl_info *mci)
+{
+	struct snps_edac_priv *priv = mci->pvt_info;
+	int rc;
+
+	rc = snps_request_ind_irq(mci);
+	if (rc > 0)
+		rc = snps_request_com_irq(mci);
+	if (rc)
+		return rc;
+
 	snps_enable_irq(priv);
 
 	return 0;
-- 
2.41.0