linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Harry Song <jundongsong1@gmail.com>
To: helgaas@kernel.org
Cc: bhelgaas@google.com, gustavo.pimentel@synopsys.com,
	jingoohan1@gmail.com, jundongsong1@gmail.com, kw@linux.com,
	linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
	lpieralisi@kernel.org, robh@kernel.org
Subject: [PATCH V2] PCI: dwc: Warn about invalid 'max-link-speed' from DT
Date: Sun, 13 Nov 2022 16:10:06 +0800	[thread overview]
Message-ID: <20221113081006.3624-1-jundongsong1@gmail.com> (raw)

of_pci_get_max_link_speed() may return a negative value,
causing the controller to not set the speed correctly.
Add a warning in case the driver engineer misses it.

Signed-off-by: Harry Song <jundongsong1@gmail.com>
---

 V2: Change the description of the subject line;
     Remove unnecessary "unlikely";

 Thanks for your comment, V1 is this one:
 https://lore.kernel.org/lkml/20221110213239.GA672651@bhelgaas/

 drivers/pci/controller/dwc/pcie-designware-ep.c   | 5 ++++-
 drivers/pci/controller/dwc/pcie-designware-host.c | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 83ddb1902..19892e939 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -739,8 +739,11 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 		return -ENOMEM;
 	ep->outbound_addr = addr;
 
-	if (pci->link_gen < 1)
+	if (pci->link_gen < 1) {
 		pci->link_gen = of_pci_get_max_link_speed(np);
+		if (pci->link_gen < 0)
+			dev_warn(dev, "Invalid to get max-link-speed from DT\n");
+	}
 
 	epc = devm_pci_epc_create(dev, &epc_ops);
 	if (IS_ERR(epc)) {
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 39f3b37d4..42633ec8c 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -429,8 +429,11 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
 		pp->io_base = pci_pio_to_address(win->res->start);
 	}
 
-	if (pci->link_gen < 1)
+	if (pci->link_gen < 1) {
 		pci->link_gen = of_pci_get_max_link_speed(np);
+		if (pci->link_gen < 0)
+			dev_warn(dev, "Invalid to get max-link-speed from DT\n");
+	}
 
 	/* Set default bus ops */
 	bridge->ops = &dw_pcie_ops;
-- 
2.25.1


                 reply	other threads:[~2022-11-13  8:11 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=20221113081006.3624-1-jundongsong1@gmail.com \
    --to=jundongsong1@gmail.com \
    --cc=bhelgaas@google.com \
    --cc=gustavo.pimentel@synopsys.com \
    --cc=helgaas@kernel.org \
    --cc=jingoohan1@gmail.com \
    --cc=kw@linux.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lpieralisi@kernel.org \
    --cc=robh@kernel.org \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).