From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Fri, 10 Mar 2023 21:34:58 +0900
Subject: PCI: dwc: Fix PORT_LINK_CONTROL update when CDM check enabled
Git-commit: cdce67099117ece371582f706c6eff7d3a65326d
Patch-mainline: 6.3-rc5
References: git-fixes

If CDM_CHECK is enabled (by the DT "snps,enable-cdm-check" property), 'val'
is overwritten by PCIE_PL_CHK_REG_CONTROL_STATUS initialization.  Commit
ec7b952f453c ("PCI: dwc: Always enable CDM check if "snps,enable-cdm-check"
exists") did not account for further usage of 'val', so we wrote improper
values to PCIE_PORT_LINK_CONTROL when the CDM check is enabled.

Move the PCIE_PORT_LINK_CONTROL update to be completely after the
PCIE_PL_CHK_REG_CONTROL_STATUS register initialization.

[bhelgaas: commit log adapted from Serge's version]
Fixes: ec7b952f453c ("PCI: dwc: Always enable CDM check if "snps,enable-cdm-check" exists")
Link: https://lore.kernel.org/r/20230310123510.675685-2-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/pci/controller/dwc/pcie-designware.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -734,11 +734,6 @@ void dw_pcie_setup(struct dw_pcie *pci)
 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
 	}
 
-	val = dw_pcie_readl_dbi(pci, PCIE_PORT_LINK_CONTROL);
-	val &= ~PORT_LINK_FAST_LINK_MODE;
-	val |= PORT_LINK_DLL_LINK_EN;
-	dw_pcie_writel_dbi(pci, PCIE_PORT_LINK_CONTROL, val);
-
 	if (of_property_read_bool(np, "snps,enable-cdm-check")) {
 		val = dw_pcie_readl_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS);
 		val |= PCIE_PL_CHK_REG_CHK_REG_CONTINUOUS |
@@ -746,6 +741,11 @@ void dw_pcie_setup(struct dw_pcie *pci)
 		dw_pcie_writel_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS, val);
 	}
 
+	val = dw_pcie_readl_dbi(pci, PCIE_PORT_LINK_CONTROL);
+	val &= ~PORT_LINK_FAST_LINK_MODE;
+	val |= PORT_LINK_DLL_LINK_EN;
+	dw_pcie_writel_dbi(pci, PCIE_PORT_LINK_CONTROL, val);
+
 	of_property_read_u32(np, "num-lanes", &pci->num_lanes);
 	if (!pci->num_lanes) {
 		dev_dbg(pci->dev, "Using h/w default number of lanes\n");