From: Anand Moon <linux.amoon@gmail.com>
To: "Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Krzysztof Wilczyński" <kwilczynski@kernel.org>,
"Manivannan Sadhasivam" <mani@kernel.org>,
"Rob Herring" <robh@kernel.org>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Krzysztof Kozlowski" <krzk+dt@kernel.org>,
"Conor Dooley" <conor+dt@kernel.org>,
"Thierry Reding" <thierry.reding@gmail.com>,
"Jonathan Hunter" <jonathanh@nvidia.com>,
linux-pci@vger.kernel.org (open list:PCI NATIVE HOST BRIDGE AND
ENDPOINT DRIVERS),
devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND
FLATTENED DEVICE TREE BINDINGS),
linux-tegra@vger.kernel.org (open list:TEGRA ARCHITECTURE
SUPPORT), linux-kernel@vger.kernel.org (open list)
Cc: Anand Moon <linux.amoon@gmail.com>,
Mikko Perttunen <mperttunen@nvidia.com>
Subject: [PATCH v1 3/5] PCI: tegra: Use readl_poll_timeout() for link status polling
Date: Fri, 26 Sep 2025 12:57:44 +0530 [thread overview]
Message-ID: <20250926072905.126737-4-linux.amoon@gmail.com> (raw)
In-Reply-To: <20250926072905.126737-1-linux.amoon@gmail.com>
Replace the manual `do-while` polling loops with the readl_poll_timeout()
helper when checking the link DL_UP and DL_LINK_ACTIVE status bits
during link bring-up. This simplifies the code by removing the open-coded
timeout logic in favor of the standard, more robust iopoll framework.
The change improves readability and reduces code duplication.
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Anand Moon <linux.amoon@gmail.com>
---
v1: dropped the include <linux/iopoll.h> header file.
---
drivers/pci/controller/pci-tegra.c | 37 +++++++++++-------------------
1 file changed, 14 insertions(+), 23 deletions(-)
diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
index 07a61d902eae..b0056818a203 100644
--- a/drivers/pci/controller/pci-tegra.c
+++ b/drivers/pci/controller/pci-tegra.c
@@ -2169,37 +2169,28 @@ static bool tegra_pcie_port_check_link(struct tegra_pcie_port *port)
value |= RP_PRIV_MISC_PRSNT_MAP_EP_PRSNT;
writel(value, port->base + RP_PRIV_MISC);
- do {
- unsigned int timeout = TEGRA_PCIE_LINKUP_TIMEOUT;
+ while (retries--) {
+ int err;
- do {
- value = readl(port->base + RP_VEND_XP);
-
- if (value & RP_VEND_XP_DL_UP)
- break;
-
- usleep_range(1000, 2000);
- } while (--timeout);
-
- if (!timeout) {
+ err = readl_poll_timeout(port->base + RP_VEND_XP, value,
+ value & RP_VEND_XP_DL_UP,
+ 1000,
+ TEGRA_PCIE_LINKUP_TIMEOUT * 1000);
+ if (err) {
dev_dbg(dev, "link %u down, retrying\n", port->index);
goto retry;
}
- timeout = TEGRA_PCIE_LINKUP_TIMEOUT;
-
- do {
- value = readl(port->base + RP_LINK_CONTROL_STATUS);
-
- if (value & RP_LINK_CONTROL_STATUS_DL_LINK_ACTIVE)
- return true;
-
- usleep_range(1000, 2000);
- } while (--timeout);
+ err = readl_poll_timeout(port->base + RP_LINK_CONTROL_STATUS,
+ value,
+ value & RP_LINK_CONTROL_STATUS_DL_LINK_ACTIVE,
+ 1000, TEGRA_PCIE_LINKUP_TIMEOUT * 1000);
+ if (!err)
+ return true;
retry:
tegra_pcie_port_reset(port);
- } while (--retries);
+ }
return false;
}
--
2.50.1
next prev parent reply other threads:[~2025-09-26 7:30 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-26 7:27 [PATCH v1 0/5] PCI: tegra: A couple of cleanups Anand Moon
2025-09-26 7:27 ` [PATCH v1 1/5] dt-bindings: PCI: Convert the existing nvidia,tegra-pcie.txt bindings documentation into a YAML schema Anand Moon
2025-09-26 13:56 ` Rob Herring
2025-09-29 7:39 ` Anand Moon
2025-09-29 13:48 ` Rob Herring
2025-09-29 15:25 ` Anand Moon
2025-09-30 14:37 ` Rob Herring
2025-09-30 16:32 ` Anand Moon
2025-10-01 15:33 ` Rob Herring
2025-10-01 18:57 ` Anand Moon
2025-09-26 7:27 ` [PATCH v1 2/5] PCI: tegra: Simplify clock handling by using clk_bulk*() functions Anand Moon
2025-09-26 18:12 ` Frank Li
2025-09-27 5:50 ` Anand Moon
2025-09-29 14:01 ` Manivannan Sadhasivam
2025-09-29 16:12 ` Anand Moon
2025-09-26 7:27 ` Anand Moon [this message]
2025-10-19 7:50 ` [PATCH v1 3/5] PCI: tegra: Use readl_poll_timeout() for link status polling Manivannan Sadhasivam
2025-10-20 12:17 ` Anand Moon
2025-10-21 1:43 ` Manivannan Sadhasivam
2025-10-24 6:17 ` Anand Moon
2025-09-26 7:27 ` [PATCH v1 4/5] PCI: tegra: Use BIT() and GENMASK() macros for register definitions Anand Moon
2025-09-26 7:27 ` [PATCH v1 5/5] PCI: tegra: Document map_lock and mask_lock usage Anand Moon
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=20250926072905.126737-4-linux.amoon@gmail.com \
--to=linux.amoon@gmail.com \
--cc=bhelgaas@google.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=jonathanh@nvidia.com \
--cc=krzk+dt@kernel.org \
--cc=kwilczynski@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=lpieralisi@kernel.org \
--cc=mani@kernel.org \
--cc=mperttunen@nvidia.com \
--cc=robh@kernel.org \
--cc=thierry.reding@gmail.com \
/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).