[PATCH v3 08/13] EDAC/synopsys: Add individual named ECC IRQs support

[Serge Semin]

Currently the DW uMCTL2 DDRC EDAC driver supports a common unnamed IRQ
only. It isn't suitable for our platform which has 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 and our platform supported by the
driver we need to 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. So the only thing we need to
do is first try to request the individual IRQs, if failed then fallback to
the common IRQ. The IRQ names are used in accordance with the DW uMCTL2
DDRC DT-bindings.

Signed-off-by: Serge Semin <Sergey.Semin at baikalelectronics.ru>
---
 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 e5359ff2ed25..6a47e53deab5 100644
--- a/drivers/edac/synopsys_edac.c
+++ b/drivers/edac/synopsys_edac.c
@@ -1524,25 +1524,96 @@ 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;
-- 
2.37.3