Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Alex Elder <elder@linaro.org>
To: davem@davemloft.net, kuba@kernel.org
Cc: bjorn.andersson@linaro.org, evgreen@chromium.org,
	cpratapa@codeaurora.org, subashab@codeaurora.org,
	elder@kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH net-next 5/6] net: ipa: move gsi_irq_init() code into setup
Date: Tue,  3 Aug 2021 09:01:02 -0500	[thread overview]
Message-ID: <20210803140103.1012697-6-elder@linaro.org> (raw)
In-Reply-To: <20210803140103.1012697-1-elder@linaro.org>

The GSI IRQ handler could be triggered as soon as it is registered
with request_irq().  The handler function, gsi_isr(), touches
hardware, meaning the IPA clock must be operational.  The IPA clock
is not operating when the handler is registered (in gsi_irq_init()),
so this is a problem.

Move the call to request_irq() for the GSI interrupt handler into
gsi_irq_setup(), which is called when the IPA clock is known to be
operational (and furthermore, the GSI firmware will have been
loaded).  Request the IRQ at the end of that function, after all
interrupt types have been disabled and masked.

Move the matching free_irq() call into gsi_irq_teardown(), and get
rid of the now empty gsi_irq_exit(),

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/net/ipa/gsi.c | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c
index be069d7c4feb9..c555ccd778bb8 100644
--- a/drivers/net/ipa/gsi.c
+++ b/drivers/net/ipa/gsi.c
@@ -1303,33 +1303,20 @@ static irqreturn_t gsi_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+/* Init function for GSI IRQ lookup; there is no gsi_irq_exit() */
 static int gsi_irq_init(struct gsi *gsi, struct platform_device *pdev)
 {
-	struct device *dev = &pdev->dev;
-	unsigned int irq;
 	int ret;
 
 	ret = platform_get_irq_byname(pdev, "gsi");
 	if (ret <= 0)
 		return ret ? : -EINVAL;
 
-	irq = ret;
-
-	ret = request_irq(irq, gsi_isr, 0, "gsi", gsi);
-	if (ret) {
-		dev_err(dev, "error %d requesting \"gsi\" IRQ\n", ret);
-		return ret;
-	}
-	gsi->irq = irq;
+	gsi->irq = ret;
 
 	return 0;
 }
 
-static void gsi_irq_exit(struct gsi *gsi)
-{
-	free_irq(gsi->irq, gsi);
-}
-
 /* Return the transaction associated with a transfer completion event */
 static struct gsi_trans *gsi_event_trans(struct gsi_channel *channel,
 					 struct gsi_event *event)
@@ -1810,6 +1797,8 @@ static void gsi_channel_teardown(struct gsi *gsi)
 /* Turn off all GSI interrupts initially */
 static int gsi_irq_setup(struct gsi *gsi)
 {
+	int ret;
+
 	/* Writing 1 indicates IRQ interrupts; 0 would be MSI */
 	iowrite32(1, gsi->virt + GSI_CNTXT_INTSET_OFFSET);
 
@@ -1835,11 +1824,16 @@ static int gsi_irq_setup(struct gsi *gsi)
 
 	iowrite32(0, gsi->virt + GSI_CNTXT_GSI_IRQ_EN_OFFSET);
 
-	return 0;
+	ret = request_irq(gsi->irq, gsi_isr, 0, "gsi", gsi);
+	if (ret)
+		dev_err(gsi->dev, "error %d requesting \"gsi\" IRQ\n", ret);
+
+	return ret;
 }
 
 static void gsi_irq_teardown(struct gsi *gsi)
 {
+	free_irq(gsi->irq, gsi);
 }
 
 /* Get # supported channel and event rings; there is no gsi_ring_teardown() */
@@ -2224,20 +2218,18 @@ int gsi_init(struct gsi *gsi, struct platform_device *pdev,
 
 	init_completion(&gsi->completion);
 
-	ret = gsi_irq_init(gsi, pdev);
+	ret = gsi_irq_init(gsi, pdev);	/* No matching exit required */
 	if (ret)
 		goto err_iounmap;
 
 	ret = gsi_channel_init(gsi, count, data);
 	if (ret)
-		goto err_irq_exit;
+		goto err_iounmap;
 
 	mutex_init(&gsi->mutex);
 
 	return 0;
 
-err_irq_exit:
-	gsi_irq_exit(gsi);
 err_iounmap:
 	iounmap(gsi->virt_raw);
 
@@ -2249,7 +2241,6 @@ void gsi_exit(struct gsi *gsi)
 {
 	mutex_destroy(&gsi->mutex);
 	gsi_channel_exit(gsi);
-	gsi_irq_exit(gsi);
 	iounmap(gsi->virt_raw);
 }
 
-- 
2.27.0


  parent reply	other threads:[~2021-08-03 14:01 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-03 14:00 [PATCH net-next 0/6] net: ipa: prepare GSI interrupts for runtime PM Alex Elder
2021-08-03 14:00 ` [PATCH net-next 1/6] net: ipa: use gsi->version for channel suspend/resume Alex Elder
2021-08-03 14:00 ` [PATCH net-next 2/6] net: ipa: move version check " Alex Elder
2021-08-03 14:01 ` [PATCH net-next 3/6] net: ipa: move some GSI setup functions Alex Elder
2021-08-03 14:01 ` [PATCH net-next 4/6] net: ipa: have gsi_irq_setup() return an error code Alex Elder
2021-08-03 14:01 ` Alex Elder [this message]
2021-08-03 14:01 ` [PATCH net-next 6/6] net: ipa: disable GSI interrupts while suspended Alex Elder
2021-08-04  9:40 ` [PATCH net-next 0/6] net: ipa: prepare GSI interrupts for runtime PM patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210803140103.1012697-6-elder@linaro.org \
    --to=elder@linaro.org \
    --cc=bjorn.andersson@linaro.org \
    --cc=cpratapa@codeaurora.org \
    --cc=davem@davemloft.net \
    --cc=elder@kernel.org \
    --cc=evgreen@chromium.org \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=subashab@codeaurora.org \
    --subject='Re: [PATCH net-next 5/6] net: ipa: move gsi_irq_init() code into setup' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).