On Fri, Mar 13, 2026 at 10:08:15AM +0800, Sherry Sun wrote:

quoted

The current DT binding for pci-imx6 specifies the 'reset-gpios'
property in the host bridge node. However, the PERST# signal logically
belongs to individual Root Ports rather than the host bridge itself.
This becomes important when supporting PCIe KeyE connector and PCI
power control framework for pci-imx6 driver, which requires properties
to be specified in Root Port nodes.

With the common Root Port parsing now handled in dw_pcie_host_init(),
update the reset GPIO handling to use the parsed port list from
bridge->ports. To maintain DT backwards compatibility, fallback to the
legacy method of parsing the host bridge node if the reset property is
not present in the Root Port node (indicated by an empty ports list).

Signed-off-by: Sherry Sun <redacted>
---
 drivers/pci/controller/dwc/pci-imx6.c | 74
+++++++++++++++++++++------
 1 file changed, 59 insertions(+), 15 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c

b/drivers/pci/controller/dwc/pci-imx6.c
index 83beca5a1fc2..cb18e1579788 100644

--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c

@@ -34,6 +34,7 @@
 #include <linux/pm_runtime.h>

 #include "../../pci.h"
+#include "../pci-host-common.h"
 #include "pcie-designware.h"

 #define IMX8MQ_GPR_PCIE_REF_USE_PAD		BIT(9)

@@ -150,7 +151,6 @@ struct imx_lut_data {

 struct imx_pcie {
 	struct dw_pcie		*pci;
-	struct gpio_desc	*reset_gpiod;
 	struct clk_bulk_data	*clks;
 	int			num_clks;
 	bool			supports_clkreq;

@@ -1222,6 +1222,44 @@ static void imx_pcie_disable_device(struct

pci_host_bridge *bridge,

quoted

 	imx_pcie_remove_lut(imx_pcie, pci_dev_id(pdev));  }

+static int imx_pcie_parse_legacy_binding(struct imx_pcie *pcie) {
+	struct device *dev = pcie->pci->dev;
+	struct pci_host_bridge *bridge = pcie->pci->pp.bridge;
+	struct pci_host_port *port;
+	struct gpio_desc *reset;
+
+	if (!bridge) {
+		dev_err(dev, "Bridge not allocated yet\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * For DT backward compatibility: if no Root Port nodes were parsed
+	 * (indicated by empty ports list), parse reset-gpios from the host
+	 * bridge node.
+	 */
+	if (!list_empty(&bridge->ports))

You should move this check and the comment to imx_pcie_host_init() and call
imx_pcie_parse_legacy_binding() conditionally to make it clear that this is a
fallback.

Ok, thanks for the suggestion, will do this in V9.

Best Regards
Sherry

- Mani

--
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