Commit fc9a7704 authored by Kishon Vijay Abraham I's avatar Kishon Vijay Abraham I Committed by Lorenzo Pieralisi
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PCI: designware-ep: Configure Resizable BAR cap to advertise the smallest size 



Configure the Resizable BAR capability to advertise the smallest size
(1MB) for a couple of reasons:

- Host side resource allocation of BAR fails for larger sizes
- Endpoint function driver does not allocate memory for all supported
  sizes in the Resizable BAR capability.

If and when there is a usecase required to add more flexibility using
the Resizable BAR capability, this can be revisited.

Signed-off-by: default avatarKishon Vijay Abraham I <kishon@ti.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent 23284ad6

drivers/pci/controller/dwc/pcie-designware-ep.c

+34 −0
Original line number Diff line number Diff line
@@ -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;

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