> -----Original Message----- > From: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Sent: Monday, October 14, 2019 8:44 PM > To: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx> > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > bhelgaas@xxxxxxxxxx; andrew.murray@xxxxxxx; > gustavo.pimentel@xxxxxxxxxxxx; jingoohan1@xxxxxxxxx; vidyas@xxxxxxxxxx; > Anvesh Salveru <anvesh.s@xxxxxxxxxxx> > Subject: Re: [PATCH v2] PCI: dwc: Add support to add GEN3 related equalization > quirks > > On Mon, Oct 14, 2019 at 12:48:29PM +0530, Pankaj Dubey wrote: > > From: Anvesh Salveru <anvesh.s@xxxxxxxxxxx> > > > > In some platforms, PCIe PHY may have issues which will prevent linkup > > to happen in GEN3 or higher speed. In case equalization fails, link > > will fallback to GEN1. > > > > DesignWare controller gives flexibility to disable GEN3 equalization > > completely or only phase 2 and 3 of equalization. > > > > This patch enables the DesignWare driver to disable the PCIe GEN3 > > equalization by enabling one of the following quirks: > > - DWC_EQUALIZATION_DISABLE: To disable GEN3 equalization all phases > > - DWC_EQ_PHASE_2_3_DISABLE: To disable GEN3 equalization phase 2 & 3 > > > > Platform drivers can set these quirks via "quirk" variable of "dw_pcie" > > struct. > > > > Signed-off-by: Anvesh Salveru <anvesh.s@xxxxxxxxxxx> > > Signed-off-by: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx> > > Acked-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx> > > Reviewed-by: Andrew Murray <andrew.murray@xxxxxxx> > > Reviewed-by: Vidya Sagar <vidyas@xxxxxxxxxx> > > --- > > Changes w.r.t v1: > > - Rebased on latest linus/master > > - Added Reviewed-by and Acked-by > > > > drivers/pci/controller/dwc/pcie-designware.c | 12 ++++++++++++ > > drivers/pci/controller/dwc/pcie-designware.h | 9 +++++++++ > > 2 files changed, 21 insertions(+) > > So this is v3 not v2, right ? > Yes, you are right. I missed this. This can be discarded, I will resend the patch with v3 tag. > Here is v2: > > https://protect2.fireeye.com/url?k=47b7cdf58f33e5e1.47b646ba- > 8ad463719e64eba8&u=https://patchwork.ozlabs.org/patch/1161958/ > > > diff --git a/drivers/pci/controller/dwc/pcie-designware.c > > b/drivers/pci/controller/dwc/pcie-designware.c > > index 820488d..e247d6d 100644 > > --- a/drivers/pci/controller/dwc/pcie-designware.c > > +++ b/drivers/pci/controller/dwc/pcie-designware.c > > @@ -556,4 +556,16 @@ void dw_pcie_setup(struct dw_pcie *pci) > > PCIE_PL_CHK_REG_CHK_REG_START; > > dw_pcie_writel_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS, > val); > > } > > + > > + if (pci->quirk & DWC_EQUALIZATION_DISABLE) { > > + val = dw_pcie_readl_dbi(pci, PCIE_PORT_GEN3_RELATED); > > + val |= PORT_LOGIC_GEN3_EQ_DISABLE; > > + dw_pcie_writel_dbi(pci, PCIE_PORT_GEN3_RELATED, val); > > + } > > + > > + if (pci->quirk & DWC_EQ_PHASE_2_3_DISABLE) { > > + val = dw_pcie_readl_dbi(pci, PCIE_PORT_GEN3_RELATED); > > + val |= PORT_LOGIC_GEN3_EQ_PHASE_2_3_DISABLE; > > + dw_pcie_writel_dbi(pci, PCIE_PORT_GEN3_RELATED, val); > > + } > > } > > diff --git a/drivers/pci/controller/dwc/pcie-designware.h > > b/drivers/pci/controller/dwc/pcie-designware.h > > index 5a18e94..7d3fe6f 100644 > > --- a/drivers/pci/controller/dwc/pcie-designware.h > > +++ b/drivers/pci/controller/dwc/pcie-designware.h > > @@ -29,6 +29,10 @@ > > #define LINK_WAIT_MAX_IATU_RETRIES 5 > > #define LINK_WAIT_IATU 9 > > > > +/* Parameters for GEN3 related quirks */ > > +#define DWC_EQUALIZATION_DISABLE BIT(1) > > +#define DWC_EQ_PHASE_2_3_DISABLE BIT(2) > > + > > /* Synopsys-specific PCIe configuration registers */ > > #define PCIE_PORT_LINK_CONTROL 0x710 > > #define PORT_LINK_MODE_MASK GENMASK(21, 16) > > @@ -60,6 +64,10 @@ > > #define PCIE_MSI_INTR0_MASK 0x82C > > #define PCIE_MSI_INTR0_STATUS 0x830 > > > > +#define PCIE_PORT_GEN3_RELATED 0x890 > > +#define PORT_LOGIC_GEN3_EQ_PHASE_2_3_DISABLE BIT(9) > > +#define PORT_LOGIC_GEN3_EQ_DISABLE BIT(16) > > + > > #define PCIE_ATU_VIEWPORT 0x900 > > #define PCIE_ATU_REGION_INBOUND BIT(31) > > #define PCIE_ATU_REGION_OUTBOUND 0 > > @@ -253,6 +261,7 @@ struct dw_pcie { > > struct dw_pcie_ep ep; > > const struct dw_pcie_ops *ops; > > unsigned int version; > > + unsigned int quirk; > > }; > > > > #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, > > pp) > > -- > > 2.7.4 > >
