[PATCH v3 4/5] PCI: tegra: Use readl_poll_timeout() for link status polling

[Anand Moon <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>
Signed-off-by: Anand Moon <linux.amoon@gmail.com>
---
v3: None
v2: None
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 32dc11d95cc9..459a2bb1a065 100644
--- a/drivers/pci/controller/pci-tegra.c
+++ b/drivers/pci/controller/pci-tegra.c
@@ -2156,37 +2156,28 @@ 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