| Message ID | 20230217093956.27126-2-Sergey.Semin@baikalelectronics.ru |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: dwc: Relatively simple fixes and cleanups | expand |
On Fri, Feb 17, 2023 at 12:39:46PM +0300, Serge Semin wrote: > 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@baikalelectronics.ru> The same fix was submitted by Yoshihiro a bit earlier: https://lore.kernel.org/linux-pci/20230216092012.3256440-1-yoshihiro.shimoda.uh@renesas.com/ I've preserved my version of the patch in the series to ease the merge procedure since the later patch in this patchset may cause conflicts. -Serge(y) > --- > 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 6d5d619ab2e9..3bb9ca14fb9c 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.c > +++ b/drivers/pci/controller/dwc/pcie-designware.c > @@ -824,6 +824,7 @@ 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) { > -- > 2.39.0 > >
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index 6d5d619ab2e9..3bb9ca14fb9c 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -824,6 +824,7 @@ 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) {
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@baikalelectronics.ru> --- drivers/pci/controller/dwc/pcie-designware.c | 1 + 1 file changed, 1 insertion(+)