linux_dsm_epyc7002/drivers/pci/host/pci-host-generic.c
Jan Kiszka 01fcb7f777 PCI: Add support for unbinding the generic PCI host controller
Add support for unbinding the generic PCI host controller.  This is
particularly useful when working in virtual environments where the
controller may come and go, but possibly not only there.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2018-05-30 11:35:23 -05:00

101 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Simple, generic PCI host controller driver targetting firmware-initialised
* systems and virtual machines (e.g. the PCI emulation provided by kvmtool).
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/pci-ecam.h>
#include <linux/platform_device.h>
static struct pci_ecam_ops gen_pci_cfg_cam_bus_ops = {
.bus_shift = 16,
.pci_ops = {
.map_bus = pci_ecam_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
}
};
static bool pci_dw_valid_device(struct pci_bus *bus, unsigned int devfn)
{
struct pci_config_window *cfg = bus->sysdata;
/*
* The Synopsys DesignWare PCIe controller in ECAM mode will not filter
* type 0 config TLPs sent to devices 1 and up on its downstream port,
* resulting in devices appearing multiple times on bus 0 unless we
* filter out those accesses here.
*/
if (bus->number == cfg->busr.start && PCI_SLOT(devfn) > 0)
return false;
return true;
}
static void __iomem *pci_dw_ecam_map_bus(struct pci_bus *bus,
unsigned int devfn, int where)
{
if (!pci_dw_valid_device(bus, devfn))
return NULL;
return pci_ecam_map_bus(bus, devfn, where);
}
static struct pci_ecam_ops pci_dw_ecam_bus_ops = {
.bus_shift = 20,
.pci_ops = {
.map_bus = pci_dw_ecam_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
}
};
static const struct of_device_id gen_pci_of_match[] = {
{ .compatible = "pci-host-cam-generic",
.data = &gen_pci_cfg_cam_bus_ops },
{ .compatible = "pci-host-ecam-generic",
.data = &pci_generic_ecam_ops },
{ .compatible = "marvell,armada8k-pcie-ecam",
.data = &pci_dw_ecam_bus_ops },
{ .compatible = "socionext,synquacer-pcie-ecam",
.data = &pci_dw_ecam_bus_ops },
{ .compatible = "snps,dw-pcie-ecam",
.data = &pci_dw_ecam_bus_ops },
{ },
};
static int gen_pci_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
struct pci_ecam_ops *ops;
of_id = of_match_node(gen_pci_of_match, pdev->dev.of_node);
ops = (struct pci_ecam_ops *)of_id->data;
return pci_host_common_probe(pdev, ops);
}
static struct platform_driver gen_pci_driver = {
.driver = {
.name = "pci-host-generic",
.of_match_table = gen_pci_of_match,
.suppress_bind_attrs = true,
},
.probe = gen_pci_probe,
.remove = pci_host_common_remove,
};
builtin_platform_driver(gen_pci_driver);