| Message ID | 20190612095339.20118-4-vidyas@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add Tegra194 PCIe support | expand |
On 6/12/19, 6:54 PM, Vidya Sagar wrote: > > Remove multiple write enable and disable sequences of dbi registers as > Tegra194 implements writes to BAR-0 register (offset: 0x10) controlled by > DBI write-lock enable bit thereby not allowing any further writes to BAR-0 > register in config space to take place. Hence enabling write permission at > the start of function and disabling the same only towards the end. > > Signed-off-by: Vidya Sagar <vidyas@nvidia.com> > Reviewed-by: Thierry Reding <treding@nvidia.com> Acked-by: Jingoo Han <jingoohan1@gmail.com> Sorry for being late. I read the previous threads. I don't think that this patch has any harmful effects. This patch looks good to me. Thank you. Best regards, Jingoo Han > --- > Changes since [v9]: > * None > > Changes since [v8]: > * None > > Changes since [v7]: > * None > > Changes since [v6]: > * None > > Changes since [v5]: > * Moved write enable to the beginning of the API and write disable to the end > > Changes since [v4]: > * None > > Changes since [v3]: > * None > > Changes since [v2]: > * None > > Changes since [v1]: > * None > > drivers/pci/controller/dwc/pcie-designware-host.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index f93252d0da5b..d3156446ff27 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -628,6 +628,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp) > u32 val, ctrl, num_ctrls; > struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > > + /* > + * Enable DBI read-only registers for writing/updating configuration. > + * Write permission gets disabled towards the end of this function. > + */ > + dw_pcie_dbi_ro_wr_en(pci); > + > dw_pcie_setup(pci); > > if (!pp->ops->msi_host_init) { > @@ -650,12 +656,10 @@ void dw_pcie_setup_rc(struct pcie_port *pp) > dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_1, 0x00000000); > > /* Setup interrupt pins */ > - dw_pcie_dbi_ro_wr_en(pci); > val = dw_pcie_readl_dbi(pci, PCI_INTERRUPT_LINE); > val &= 0xffff00ff; > val |= 0x00000100; > dw_pcie_writel_dbi(pci, PCI_INTERRUPT_LINE, val); > - dw_pcie_dbi_ro_wr_dis(pci); > > /* Setup bus numbers */ > val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS); > @@ -687,15 +691,13 @@ void dw_pcie_setup_rc(struct pcie_port *pp) > > dw_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0); > > - /* Enable write permission for the DBI read-only register */ > - dw_pcie_dbi_ro_wr_en(pci); > /* Program correct class for RC */ > dw_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI); > - /* Better disable write permission right after the update */ > - dw_pcie_dbi_ro_wr_dis(pci); > > dw_pcie_rd_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, &val); > val |= PORT_LOGIC_SPEED_CHANGE; > dw_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val); > + > + dw_pcie_dbi_ro_wr_dis(pci); > } > EXPORT_SYMBOL_GPL(dw_pcie_setup_rc); > -- > 2.17.1
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index f93252d0da5b..d3156446ff27 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -628,6 +628,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp) u32 val, ctrl, num_ctrls; struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + /* + * Enable DBI read-only registers for writing/updating configuration. + * Write permission gets disabled towards the end of this function. + */ + dw_pcie_dbi_ro_wr_en(pci); + dw_pcie_setup(pci); if (!pp->ops->msi_host_init) { @@ -650,12 +656,10 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_1, 0x00000000); /* Setup interrupt pins */ - dw_pcie_dbi_ro_wr_en(pci); val = dw_pcie_readl_dbi(pci, PCI_INTERRUPT_LINE); val &= 0xffff00ff; val |= 0x00000100; dw_pcie_writel_dbi(pci, PCI_INTERRUPT_LINE, val); - dw_pcie_dbi_ro_wr_dis(pci); /* Setup bus numbers */ val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS); @@ -687,15 +691,13 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dw_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0); - /* Enable write permission for the DBI read-only register */ - dw_pcie_dbi_ro_wr_en(pci); /* Program correct class for RC */ dw_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI); - /* Better disable write permission right after the update */ - dw_pcie_dbi_ro_wr_dis(pci); dw_pcie_rd_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, &val); val |= PORT_LOGIC_SPEED_CHANGE; dw_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val); + + dw_pcie_dbi_ro_wr_dis(pci); } EXPORT_SYMBOL_GPL(dw_pcie_setup_rc);