From: Ansuel Smith ansuelsmth@gmail.com
commit d3d4d028afb785e52c55024d779089654f8302e7 upstream.
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.
Link: https://lore.kernel.org/r/20200901124955.137-1-ansuelsmth@gmail.com Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver") Signed-off-by: Ansuel Smith ansuelsmth@gmail.com Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Reviewed-by: Bjorn Andersson bjorn.andersson@linaro.org Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/pci/controller/dwc/pcie-qcom.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
--- 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(struc 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 q 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");