Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0+
/*
 * PCI Express Hot Plug Controller Driver
 *
 * Copyright (C) 1995,2001 Compaq Computer Corporation
 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001 IBM Corp.
 * Copyright (C) 2003-2004 Intel Corporation
 *
 * All rights reserved.
 *
 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
 *
 */
 
#define dev_fmt(fmt) "pciehp: " fmt
 
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "../pci.h"
#include "pciehp.h"
 
/**
 * pciehp_configure_device() - enumerate PCI devices below a hotplug bridge
 * @ctrl: PCIe hotplug controller
 *
 * Enumerate PCI devices below a hotplug bridge and add them to the system.
 * Return 0 on success, %-EEXIST if the devices are already enumerated or
 * %-ENODEV if enumeration failed.
 */
int pciehp_configure_device(struct controller *ctrl)
{
<------>struct pci_dev *dev;
<------>struct pci_dev *bridge = ctrl->pcie->port;
<------>struct pci_bus *parent = bridge->subordinate;
<------>int num, ret = 0;
 
<------>pci_lock_rescan_remove();
 
<------>dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
<------>if (dev) {
<------><------>/*
<------><------> * The device is already there. Either configured by the
<------><------> * boot firmware or a previous hotplug event.
<------><------> */
<------><------>ctrl_dbg(ctrl, "Device %s already exists at %04x:%02x:00, skipping hot-add\n",
<------><------><------> pci_name(dev), pci_domain_nr(parent), parent->number);
<------><------>pci_dev_put(dev);
<------><------>ret = -EEXIST;
<------><------>goto out;
<------>}
 
<------>num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
<------>if (num == 0) {
<------><------>ctrl_err(ctrl, "No new device found\n");
<------><------>ret = -ENODEV;
<------><------>goto out;
<------>}
 
<------>for_each_pci_bridge(dev, parent)
<------><------>pci_hp_add_bridge(dev);
 
<------>pci_assign_unassigned_bridge_resources(bridge);
<------>pcie_bus_configure_settings(parent);
<------>pci_bus_add_devices(parent);
 
 out:
<------>pci_unlock_rescan_remove();
<------>return ret;
}
 
/**
 * pciehp_unconfigure_device() - remove PCI devices below a hotplug bridge
 * @ctrl: PCIe hotplug controller
 * @presence: whether the card is still present in the slot;
 *	true for safe removal via sysfs or an Attention Button press,
 *	false for surprise removal
 *
 * Unbind PCI devices below a hotplug bridge from their drivers and remove
 * them from the system.  Safely removed devices are quiesced.  Surprise
 * removed devices are marked as such to prevent further accesses.
 */
void pciehp_unconfigure_device(struct controller *ctrl, bool presence)
{
<------>struct pci_dev *dev, *temp;
<------>struct pci_bus *parent = ctrl->pcie->port->subordinate;
<------>u16 command;
 
<------>ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
<------><------> __func__, pci_domain_nr(parent), parent->number);
 
<------>if (!presence)
<------><------>pci_walk_bus(parent, pci_dev_set_disconnected, NULL);
 
<------>pci_lock_rescan_remove();
 
<------>/*
<------> * Stopping an SR-IOV PF device removes all the associated VFs,
<------> * which will update the bus->devices list and confuse the
<------> * iterator.  Therefore, iterate in reverse so we remove the VFs
<------> * first, then the PF.  We do the same in pci_stop_bus_device().
<------> */
<------>list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
<------><------><------><------><------> bus_list) {
<------><------>pci_dev_get(dev);
<------><------>pci_stop_and_remove_bus_device(dev);
<------><------>/*
<------><------> * Ensure that no new Requests will be generated from
<------><------> * the device.
<------><------> */
<------><------>if (presence) {
<------><------><------>pci_read_config_word(dev, PCI_COMMAND, &command);
<------><------><------>command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
<------><------><------>command |= PCI_COMMAND_INTX_DISABLE;
<------><------><------>pci_write_config_word(dev, PCI_COMMAND, command);
<------><------>}
<------><------>pci_dev_put(dev);
<------>}
 
<------>pci_unlock_rescan_remove();
}