On 31.01.2024 21:51, Sergey Shtylyov wrote:

   I said the subject needs to be changed to "net: ravb: Move getting/requesting IRQs in
the probe() method", not "net: ravb: Move IRQs getting/requesting in the probe() method".
That's not very proper English, AFAIK! =)

It seems I messed this up.

On 1/31/24 11:41 AM, Claudiu wrote:

quoted

From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

The runtime PM implementation will disable clocks at the end of
ravb_probe(). As some IP variants switch to reset mode as a result of
setting module standby through clock disable APIs, to implement runtime PM
the resource parsing and requesting are moved in the probe function and IP
settings are moved in the open function. This is done because at the end of
the probe some IP variants will switch anyway to reset mode and the
registers content is lost. Also keeping only register settings operations
in the ravb_open()/ravb_close() functions will make them faster.

Commit moves IRQ requests to ravb_probe() to have all the IRQs ready when
the interface is open. As now IRQs getting/requesting are in a single place

   Again, "getting/requesting IRQs is done"...

quoted

there is no need to keep intermediary data (like ravb_rx_irqs[] and
ravb_tx_irqs[] arrays or IRQs in struct ravb_private).

In order to avoid accessing the IP registers while the IP is runtime
suspended (e.g. in the timeframe b/w the probe requests shared IRQs and
IP clocks are enabled) in the interrupt handlers were introduced

   But can't we just request our IRQs after we call pm_runtime_resume_and_get()?
We proaobly can... but then again, we call pm_runtime_put_sync() in the remove()
method before the IRQs are freed...  So, it still seems OK that we're adding
pm_runtime_active() calls to the IRQ handlers in this very patch, not when we'll
start calling the RPM APIs in the ndo_{open|close}() methods, correct? :-)

Yes, it should be safe.

quoted

pm_runtime_active() checks. The device runtime PM usage counter has been
incremented to avoid disabling the device's clocks while the check is in
progress (if any).

This is a preparatory change to add runtime PM support for all IP variants.

Reviewed-by: Sergey Shtylyov <redacted>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

[...]

quoted

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index e70c930840ce..f9297224e527 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c

[...]

quoted

@@ -1092,11 +1082,23 @@ static irqreturn_t ravb_emac_interrupt(int irq, void *dev_id)
 {
 	struct net_device *ndev = dev_id;
 	struct ravb_private *priv = netdev_priv(ndev);
+	struct device *dev = &priv->pdev->dev;
+	irqreturn_t result = IRQ_HANDLED;
+
+	pm_runtime_get_noresume(dev);
+

   Not sure we need en empty line here...

That's a personal taste... more like to emphasize that this is PM runtime
"protected"... Same for the rest of occurrences you signaled below.

quoted

+	if (unlikely(!pm_runtime_active(dev))) {
+		result = IRQ_NONE;
+		goto out_rpm_put;
+	}
 
 	spin_lock(&priv->lock);
 	ravb_emac_interrupt_unlocked(ndev);
 	spin_unlock(&priv->lock);
-	return IRQ_HANDLED;
+
+out_rpm_put:
+	pm_runtime_put_noidle(dev);
+	return result;
 }
 
 /* Error interrupt handler */

@@ -1176,9 +1178,15 @@ static irqreturn_t ravb_interrupt(int irq, void *dev_id)
 	struct net_device *ndev = dev_id;
 	struct ravb_private *priv = netdev_priv(ndev);
 	const struct ravb_hw_info *info = priv->info;
+	struct device *dev = &priv->pdev->dev;
 	irqreturn_t result = IRQ_NONE;
 	u32 iss;
 
+	pm_runtime_get_noresume(dev);
+

   And here...

quoted

+	if (unlikely(!pm_runtime_active(dev)))
+		goto out_rpm_put;
+
 	spin_lock(&priv->lock);
 	/* Get interrupt status */
 	iss = ravb_read(ndev, ISS);

[...]

quoted

@@ -1230,9 +1241,15 @@ static irqreturn_t ravb_multi_interrupt(int irq, void *dev_id)
 {
 	struct net_device *ndev = dev_id;
 	struct ravb_private *priv = netdev_priv(ndev);
+	struct device *dev = &priv->pdev->dev;
 	irqreturn_t result = IRQ_NONE;
 	u32 iss;
 
+	pm_runtime_get_noresume(dev);
+

   Here too...

quoted

+	if (unlikely(!pm_runtime_active(dev)))
+		goto out_rpm_put;
+
 	spin_lock(&priv->lock);
 	/* Get interrupt status */
 	iss = ravb_read(ndev, ISS);

[...]

quoted

@@ -1261,8 +1281,14 @@ static irqreturn_t ravb_dma_interrupt(int irq, void *dev_id, int q)
 {
 	struct net_device *ndev = dev_id;
 	struct ravb_private *priv = netdev_priv(ndev);
+	struct device *dev = &priv->pdev->dev;
 	irqreturn_t result = IRQ_NONE;
 
+	pm_runtime_get_noresume(dev);
+

   Here as well...

quoted

+	if (unlikely(!pm_runtime_active(dev)))
+		goto out_rpm_put;
+
 	spin_lock(&priv->lock);
 
 	/* Network control/Best effort queue RX/TX */

[...]

quoted

@@ -2616,6 +2548,90 @@ static void ravb_parse_delay_mode(struct device_node *np, struct net_device *nde
 	}
 }
 
+static int ravb_setup_irq(struct ravb_private *priv, const char *irq_name,
+			  const char *ch, int *irq, irq_handler_t handler)
+{
+	struct platform_device *pdev = priv->pdev;
+	struct net_device *ndev = priv->ndev;
+	struct device *dev = &pdev->dev;
+	const char *dev_name;
+	unsigned long flags;
+	int error;
+
+	if (irq_name) {
+		dev_name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", ndev->name, ch);
+		if (!dev_name)
+			return -ENOMEM;
+
+		*irq = platform_get_irq_byname(pdev, irq_name);
+		flags = 0;
+	} else {
+		dev_name = ndev->name;
+		*irq = platform_get_irq(pdev, 0);
+		flags = IRQF_SHARED;

   Perhaps it's worth passing flags as a parameter here instead?

I don't see it like this. We need this flag for a single call of
ravb_setup_irq(), we can determine for which call we need to set this flag
so I think it is redundant to have an extra argument for it.

quoted

+	}
+	if (*irq < 0)
+		return *irq;
+
+	error = devm_request_irq(dev, *irq, handler, flags, dev_name, ndev);
+	if (error)
+		netdev_err(ndev, "cannot request IRQ %s\n", dev_name);
+
+	return error;
+}

[...]

MBR, Sergey