diff mbox series

PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0

Message ID 20200901124955.137-1-ansuelsmth@gmail.com
State Accepted
Commit d3d4d028afb785e52c55024d779089654f8302e7
Headers show
Series PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0 | expand

Commit Message

Christian Marangi Sept. 1, 2020, 12:49 p.m. UTC 
Qsdk U-Boot can incorrectly leave the PCIe interface in an undefined
state if bootm command is used instead of bootipq. This is caused by the
not deinit of PCIe when bootm is called. Reset the PCIe before init
anyway to fix this U-Boot bug.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
Cc: stable@vger.kernel.org # v4.19+
---
 drivers/pci/controller/dwc/pcie-qcom.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 3aac77a295ba..82336bbaf8dc 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -302,6 +302,9 @@  static void qcom_pcie_deinit_2_1_0(struct qcom_pcie *pcie)
 	reset_control_assert(res->por_reset);
 	reset_control_assert(res->ext_reset);
 	reset_control_assert(res->phy_reset);
+
+	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
 	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
 }
 
@@ -314,6 +317,16 @@  static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
 	u32 val;
 	int ret;
 
+	/* reset the PCIe interface as uboot can leave it undefined state */
+	reset_control_assert(res->pci_reset);
+	reset_control_assert(res->axi_reset);
+	reset_control_assert(res->ahb_reset);
+	reset_control_assert(res->por_reset);
+	reset_control_assert(res->ext_reset);
+	reset_control_assert(res->phy_reset);
+
+	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
 	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
 	if (ret < 0) {
 		dev_err(dev, "cannot enable regulators\n");