On Mon, Mar 25, 2019 at 02:04:58PM +0530, Kishon Vijay Abraham I wrote:
> Configure RESBAR capability to advertise the smallest size (1MB) for
> couple of reasons. A) Host side resource allocation of BAR fails for
> larger sizes. B) Endpoint function driver does not allocate memory
> for all supported sizes in RESBAR capability.
> If and when there is a usecase required to add more flexibility using
> RESBAR, this can be revisited.
The #define used in the code below is "REBAR"; maybe spell it out
once and then use REBAR instead of RESBAR?
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> .../pci/controller/dwc/pcie-designware-ep.c | 34 +++++++++++++++++++
> 1 file changed, 34 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 74477ad7467f..0c208b9bda43 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -504,10 +504,32 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
> pci_epc_mem_exit(epc);
> }
>
> +static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
> +{
> + u32 header;
> + int pos = PCI_CFG_SPACE_SIZE;
> +
> + while (pos) {
> + header = dw_pcie_readl_dbi(pci, pos);
> + if (PCI_EXT_CAP_ID(header) == cap)
> + return pos;
> +
> + pos = PCI_EXT_CAP_NEXT(header);
> + if (!pos)
> + break;
> + }
> +
> + return 0;
> +}
> +
> int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> {
> + int i;
> int ret;
> + u32 reg;
> void *addr;
> + unsigned int nbars;
> + unsigned int offset;
> struct pci_epc *epc;
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> struct device *dev = pci->dev;
> @@ -591,6 +613,18 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
>
> ep->msix_cap = dw_pcie_ep_find_capability(pci, PCI_CAP_ID_MSIX);
>
> + offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR);
> + if (offset) {
> + reg = dw_pcie_readl_dbi(pci, offset + PCI_REBAR_CTRL);
> + nbars = (reg & PCI_REBAR_CTRL_NBAR_MASK) >>
> + PCI_REBAR_CTRL_NBAR_SHIFT;
> +
> + dw_pcie_dbi_ro_wr_en(pci);
> + for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL)
> + dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0);
> + dw_pcie_dbi_ro_wr_dis(pci);
> + }
> +
> dw_pcie_setup(pci);
>
> return 0;
> --
> 2.17.1
>
