[PATCH RESEND v2 01/11] PCI: dwc: Fix port link CSR improper init if CDM check enabled

From: Serge Semin
Date: Mon Mar 13 2023 - 16:08:59 EST


If CDM_CHECK capability is set then the local variable 'val' will be
overwritten in the dw_pcie_setup() method in the PL_CHK register
initialization procedure. Thus further variable usage in the framework of
the PCIE_PORT_LINK_CONTROL register initialization must imply the variable
re-initialization. Alas it hasn't been taken into account in the
commit ec7b952f453c ("PCI: dwc: Always enable CDM check if
"snps,enable-cdm-check" exists"). Due to that the PCIE_PORT_LINK_CONTROL
register will be written with improper value in case if the CDM-check is
enabled. Let's fix this by re-initializing the 'val' variable with the
PCIE_PORT_LINK_CONTROL CSR content before link-mode initialization.

Fixes: ec7b952f453c ("PCI: dwc: Always enable CDM check if "snps,enable-cdm-check" exists")
Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 53a16b8b6ac2..04fedd257ef1 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -1019,6 +1019,7 @@ void dw_pcie_setup(struct dw_pcie *pci)
}

/* Set the number of lanes */
+ val = dw_pcie_readl_dbi(pci, PCIE_PORT_LINK_CONTROL);
val &= ~PORT_LINK_FAST_LINK_MODE;
val &= ~PORT_LINK_MODE_MASK;
switch (pci->num_lanes) {
--
2.39.2