On 1/28/2026 8:17 PM, Bjorn Andersson wrote:

On Wed, Jan 28, 2026 at 05:10:43PM +0530, Krishna Chaitanya Chundru wrote:

quoted

Add pme_turn_off() support and use DWC common suspend resume methods
for device D3cold entry & exit. If the device is not kept in D3cold
use existing methods like keeping icc votes, opp votes etc.. intact.

In qcom_pcie_deinit_2_7_0(), explicitly disable PCIe clocks and resets
in the controller.

Remove suspended flag from qcom_pcie structure as it is no longer needed.

Signed-off-by: Krishna Chaitanya Chundru <redacted>
---
  drivers/pci/controller/dwc/pcie-qcom.c | 114 ++++++++++++++++++++-------------
  1 file changed, 68 insertions(+), 46 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c

[..]

quoted

@@ -2016,53 +2030,51 @@ static int qcom_pcie_suspend_noirq(struct device *dev)
  	if (!pcie)
  		return 0;
  
-	/*
-	 * Set minimum bandwidth required to keep data path functional during
-	 * suspend.
-	 */
-	if (pcie->icc_mem) {
-		ret = icc_set_bw(pcie->icc_mem, 0, kBps_to_icc(1));
-		if (ret) {
-			dev_err(dev,
-				"Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
-				ret);
-			return ret;
-		}
-	}
+	ret = dw_pcie_suspend_noirq(pcie->pci);
+	if (ret)
+		return ret;
  
-	/*
-	 * Turn OFF the resources only for controllers without active PCIe
-	 * devices. For controllers with active devices, the resources are kept
-	 * ON and the link is expected to be in L0/L1 (sub)states.
-	 *
-	 * Turning OFF the resources for controllers with active PCIe devices
-	 * will trigger access violation during the end of the suspend cycle,
-	 * as kernel tries to access the PCIe devices config space for masking
-	 * MSIs.
-	 *
-	 * Also, it is not desirable to put the link into L2/L3 state as that
-	 * implies VDD supply will be removed and the devices may go into
-	 * powerdown state. This will affect the lifetime of the storage devices
-	 * like NVMe.
-	 */
-	if (!dw_pcie_link_up(pcie->pci)) {
-		qcom_pcie_host_deinit(&pcie->pci->pp);
-		pcie->suspended = true;
-	}
+	if (pcie->pci->suspended) {

I think this is okay for now, but I'd prefer changing the return value
of dw_pcie_suspend_noirq() to indicate if it did stop the link or not
(two different success values) - rather than deriving that information
by peeking into the dw_pcie struct and conclude that
dw_pcie_suspend_noirq() did reach the end.

quoted

+		ret = icc_disable(pcie->icc_mem);
+		if (ret)
+			dev_err(dev, "Failed to disable PCIe-MEM interconnect path: %d\n", ret);
  
-	/*
-	 * Only disable CPU-PCIe interconnect path if the suspend is non-S2RAM.
-	 * Because on some platforms, DBI access can happen very late during the
-	 * S2RAM and a non-active CPU-PCIe interconnect path may lead to NoC
-	 * error.
-	 */
-	if (pm_suspend_target_state != PM_SUSPEND_MEM) {
  		ret = icc_disable(pcie->icc_cpu);
  		if (ret)
  			dev_err(dev, "Failed to disable CPU-PCIe interconnect path: %d\n", ret);
  
  		if (pcie->use_pm_opp)
  			dev_pm_opp_set_opp(pcie->pci->dev, NULL);
+	} else {
+		/*
+		 * Set minimum bandwidth required to keep data path functional during
+		 * suspend.
+		 */
+		if (pcie->icc_mem) {
+			ret = icc_set_bw(pcie->icc_mem, 0, kBps_to_icc(1));
+			if (ret) {
+				dev_err(dev,
+					"Failed to set bandwidth for PCIe-MEM interconnect path: %d\n",
+					ret);
+				return ret;
+			}
+		}
+
+		/*
+		 * Only disable CPU-PCIe interconnect path if the suspend is non-S2RAM.
+		 * Because on some platforms, DBI access can happen very late during the
+		 * S2RAM and a non-active CPU-PCIe interconnect path may lead to NoC
+		 * error.
+		 */
+		if (pm_suspend_target_state != PM_SUSPEND_MEM) {
+			ret = icc_disable(pcie->icc_cpu);
+			if (ret)
+				dev_err(dev, "Failed to disable CPU-PCIe interconnect path: %d\n",
+					ret);
+
+			if (pcie->use_pm_opp)
+				dev_pm_opp_set_opp(pcie->pci->dev, NULL);
+		}
  	}
  	return ret;
  }

@@ -2076,20 +2088,30 @@ static int qcom_pcie_resume_noirq(struct device *dev)
  	if (!pcie)
  		return 0;
  
-	if (pm_suspend_target_state != PM_SUSPEND_MEM) {
+	if (pcie->pci->suspended) {
  		ret = icc_enable(pcie->icc_cpu);
  		if (ret) {
  			dev_err(dev, "Failed to enable CPU-PCIe interconnect path: %d\n", ret);
  			return ret;
  		}
-	}
  
-	if (pcie->suspended) {
-		ret = qcom_pcie_host_init(&pcie->pci->pp);
+		ret = icc_enable(pcie->icc_mem);
+		if (ret) {
+			dev_err(dev, "Failed to enable PCIe-MEM interconnect path: %d\n", ret);

I think you should revert icc_enable(pcie->icc_cpu) here, to avoid
leaving the bus voted for with the PCIe controller resume aborted.

quoted

+			return ret;
+		}
+		ret = dw_pcie_resume_noirq(pcie->pci);
  		if (ret)

And Both icc_cpu and icc_mem here.

Ack, I will do this in V2.

- Krishna Chaitanya.

Regards,
Bjorn

quoted

  			return ret;
-
-		pcie->suspended = false;
+	} else {
+		if (pm_suspend_target_state != PM_SUSPEND_MEM) {
+			ret = icc_enable(pcie->icc_cpu);
+			if (ret) {
+				dev_err(dev, "Failed to enable CPU-PCIe interconnect path: %d\n",
+					ret);
+				return ret;
+			}
+		}
  	}
  
  	qcom_pcie_icc_opp_update(pcie);

-- 
2.34.1