| // 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> |
| * |
| * Authors: |
| * Dan Zink <dan.zink@compaq.com> |
| * Greg Kroah-Hartman <greg@kroah.com> |
| * Dely Sy <dely.l.sy@intel.com>" |
| */ |
| |
| #define pr_fmt(fmt) "pciehp: " fmt |
| #define dev_fmt pr_fmt |
| |
| #include <linux/moduleparam.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.h> |
| #include <linux/types.h> |
| #include <linux/pci.h> |
| #include "pciehp.h" |
| |
| #include "../pci.h" |
| |
| /* Global variables */ |
| bool pciehp_poll_mode; |
| int pciehp_poll_time; |
| |
| /* |
| * not really modular, but the easiest way to keep compat with existing |
| * bootargs behaviour is to continue using module_param here. |
| */ |
| module_param(pciehp_poll_mode, bool, 0644); |
| module_param(pciehp_poll_time, int, 0644); |
| MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not"); |
| MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds"); |
| |
| static int set_attention_status(struct hotplug_slot *slot, u8 value); |
| static int get_power_status(struct hotplug_slot *slot, u8 *value); |
| static int get_latch_status(struct hotplug_slot *slot, u8 *value); |
| static int get_adapter_status(struct hotplug_slot *slot, u8 *value); |
| |
| static int init_slot(struct controller *ctrl) |
| { |
| struct hotplug_slot_ops *ops; |
| char name[SLOT_NAME_SIZE]; |
| int retval; |
| |
| /* Setup hotplug slot ops */ |
| ops = kzalloc(sizeof(*ops), GFP_KERNEL); |
| if (!ops) |
| return -ENOMEM; |
| |
| ops->enable_slot = pciehp_sysfs_enable_slot; |
| ops->disable_slot = pciehp_sysfs_disable_slot; |
| ops->get_power_status = get_power_status; |
| ops->get_adapter_status = get_adapter_status; |
| ops->reset_slot = pciehp_reset_slot; |
| if (MRL_SENS(ctrl)) |
| ops->get_latch_status = get_latch_status; |
| if (ATTN_LED(ctrl)) { |
| ops->get_attention_status = pciehp_get_attention_status; |
| ops->set_attention_status = set_attention_status; |
| } else if (ctrl->pcie->port->hotplug_user_indicators) { |
| ops->get_attention_status = pciehp_get_raw_indicator_status; |
| ops->set_attention_status = pciehp_set_raw_indicator_status; |
| } |
| |
| /* register this slot with the hotplug pci core */ |
| ctrl->hotplug_slot.ops = ops; |
| snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl)); |
| |
| retval = pci_hp_initialize(&ctrl->hotplug_slot, |
| ctrl->pcie->port->subordinate, 0, name); |
| if (retval) { |
| ctrl_err(ctrl, "pci_hp_initialize failed: error %d\n", retval); |
| kfree(ops); |
| } |
| return retval; |
| } |
| |
| static void cleanup_slot(struct controller *ctrl) |
| { |
| struct hotplug_slot *hotplug_slot = &ctrl->hotplug_slot; |
| |
| pci_hp_destroy(hotplug_slot); |
| kfree(hotplug_slot->ops); |
| } |
| |
| /* |
| * set_attention_status - Turns the Attention Indicator on, off or blinking |
| */ |
| static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| struct pci_dev *pdev = ctrl->pcie->port; |
| |
| if (status) |
| status <<= PCI_EXP_SLTCTL_ATTN_IND_SHIFT; |
| else |
| status = PCI_EXP_SLTCTL_ATTN_IND_OFF; |
| |
| pci_config_pm_runtime_get(pdev); |
| pciehp_set_indicators(ctrl, INDICATOR_NOOP, status); |
| pci_config_pm_runtime_put(pdev); |
| return 0; |
| } |
| |
| static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| struct pci_dev *pdev = ctrl->pcie->port; |
| |
| pci_config_pm_runtime_get(pdev); |
| pciehp_get_power_status(ctrl, value); |
| pci_config_pm_runtime_put(pdev); |
| return 0; |
| } |
| |
| static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| struct pci_dev *pdev = ctrl->pcie->port; |
| |
| pci_config_pm_runtime_get(pdev); |
| pciehp_get_latch_status(ctrl, value); |
| pci_config_pm_runtime_put(pdev); |
| return 0; |
| } |
| |
| static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| struct pci_dev *pdev = ctrl->pcie->port; |
| int ret; |
| |
| pci_config_pm_runtime_get(pdev); |
| ret = pciehp_card_present_or_link_active(ctrl); |
| pci_config_pm_runtime_put(pdev); |
| if (ret < 0) |
| return ret; |
| |
| *value = ret; |
| return 0; |
| } |
| |
| /** |
| * pciehp_check_presence() - synthesize event if presence has changed |
| * @ctrl: controller to check |
| * |
| * On probe and resume, an explicit presence check is necessary to bring up an |
| * occupied slot or bring down an unoccupied slot. This can't be triggered by |
| * events in the Slot Status register, they may be stale and are therefore |
| * cleared. Secondly, sending an interrupt for "events that occur while |
| * interrupt generation is disabled [when] interrupt generation is subsequently |
| * enabled" is optional per PCIe r4.0, sec 6.7.3.4. |
| */ |
| static void pciehp_check_presence(struct controller *ctrl) |
| { |
| int occupied; |
| |
| down_read(&ctrl->reset_lock); |
| mutex_lock(&ctrl->state_lock); |
| |
| occupied = pciehp_card_present_or_link_active(ctrl); |
| if ((occupied > 0 && (ctrl->state == OFF_STATE || |
| ctrl->state == BLINKINGON_STATE)) || |
| (!occupied && (ctrl->state == ON_STATE || |
| ctrl->state == BLINKINGOFF_STATE))) |
| pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC); |
| |
| mutex_unlock(&ctrl->state_lock); |
| up_read(&ctrl->reset_lock); |
| } |
| |
| static int pciehp_probe(struct pcie_device *dev) |
| { |
| int rc; |
| struct controller *ctrl; |
| |
| /* If this is not a "hotplug" service, we have no business here. */ |
| if (dev->service != PCIE_PORT_SERVICE_HP) |
| return -ENODEV; |
| |
| if (!dev->port->subordinate) { |
| /* Can happen if we run out of bus numbers during probe */ |
| pci_err(dev->port, |
| "Hotplug bridge without secondary bus, ignoring\n"); |
| return -ENODEV; |
| } |
| |
| ctrl = pcie_init(dev); |
| if (!ctrl) { |
| pci_err(dev->port, "Controller initialization failed\n"); |
| return -ENODEV; |
| } |
| set_service_data(dev, ctrl); |
| |
| /* Setup the slot information structures */ |
| rc = init_slot(ctrl); |
| if (rc) { |
| if (rc == -EBUSY) |
| ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n"); |
| else |
| ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc); |
| goto err_out_release_ctlr; |
| } |
| |
| /* Enable events after we have setup the data structures */ |
| rc = pcie_init_notification(ctrl); |
| if (rc) { |
| ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc); |
| goto err_out_free_ctrl_slot; |
| } |
| |
| /* Publish to user space */ |
| rc = pci_hp_add(&ctrl->hotplug_slot); |
| if (rc) { |
| ctrl_err(ctrl, "Publication to user space failed (%d)\n", rc); |
| goto err_out_shutdown_notification; |
| } |
| |
| pciehp_check_presence(ctrl); |
| |
| return 0; |
| |
| err_out_shutdown_notification: |
| pcie_shutdown_notification(ctrl); |
| err_out_free_ctrl_slot: |
| cleanup_slot(ctrl); |
| err_out_release_ctlr: |
| pciehp_release_ctrl(ctrl); |
| return -ENODEV; |
| } |
| |
| static void pciehp_remove(struct pcie_device *dev) |
| { |
| struct controller *ctrl = get_service_data(dev); |
| |
| pci_hp_del(&ctrl->hotplug_slot); |
| pcie_shutdown_notification(ctrl); |
| cleanup_slot(ctrl); |
| pciehp_release_ctrl(ctrl); |
| } |
| |
| #ifdef CONFIG_PM |
| static bool pme_is_native(struct pcie_device *dev) |
| { |
| const struct pci_host_bridge *host; |
| |
| host = pci_find_host_bridge(dev->port->bus); |
| return pcie_ports_native || host->native_pme; |
| } |
| |
| static void pciehp_disable_interrupt(struct pcie_device *dev) |
| { |
| /* |
| * Disable hotplug interrupt so that it does not trigger |
| * immediately when the downstream link goes down. |
| */ |
| if (pme_is_native(dev)) |
| pcie_disable_interrupt(get_service_data(dev)); |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int pciehp_suspend(struct pcie_device *dev) |
| { |
| /* |
| * If the port is already runtime suspended we can keep it that |
| * way. |
| */ |
| if (dev_pm_skip_suspend(&dev->port->dev)) |
| return 0; |
| |
| pciehp_disable_interrupt(dev); |
| return 0; |
| } |
| |
| static int pciehp_resume_noirq(struct pcie_device *dev) |
| { |
| struct controller *ctrl = get_service_data(dev); |
| |
| /* pci_restore_state() just wrote to the Slot Control register */ |
| ctrl->cmd_started = jiffies; |
| ctrl->cmd_busy = true; |
| |
| /* clear spurious events from rediscovery of inserted card */ |
| if (ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE) |
| pcie_clear_hotplug_events(ctrl); |
| |
| return 0; |
| } |
| #endif |
| |
| static int pciehp_resume(struct pcie_device *dev) |
| { |
| struct controller *ctrl = get_service_data(dev); |
| |
| if (pme_is_native(dev)) |
| pcie_enable_interrupt(ctrl); |
| |
| pciehp_check_presence(ctrl); |
| |
| return 0; |
| } |
| |
| static int pciehp_runtime_suspend(struct pcie_device *dev) |
| { |
| pciehp_disable_interrupt(dev); |
| return 0; |
| } |
| |
| static int pciehp_runtime_resume(struct pcie_device *dev) |
| { |
| struct controller *ctrl = get_service_data(dev); |
| |
| /* pci_restore_state() just wrote to the Slot Control register */ |
| ctrl->cmd_started = jiffies; |
| ctrl->cmd_busy = true; |
| |
| /* clear spurious events from rediscovery of inserted card */ |
| if ((ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE) && |
| pme_is_native(dev)) |
| pcie_clear_hotplug_events(ctrl); |
| |
| return pciehp_resume(dev); |
| } |
| #endif /* PM */ |
| |
| static struct pcie_port_service_driver hpdriver_portdrv = { |
| .name = "pciehp", |
| .port_type = PCIE_ANY_PORT, |
| .service = PCIE_PORT_SERVICE_HP, |
| |
| .probe = pciehp_probe, |
| .remove = pciehp_remove, |
| |
| #ifdef CONFIG_PM |
| #ifdef CONFIG_PM_SLEEP |
| .suspend = pciehp_suspend, |
| .resume_noirq = pciehp_resume_noirq, |
| .resume = pciehp_resume, |
| #endif |
| .runtime_suspend = pciehp_runtime_suspend, |
| .runtime_resume = pciehp_runtime_resume, |
| #endif /* PM */ |
| }; |
| |
| int __init pcie_hp_init(void) |
| { |
| int retval = 0; |
| |
| retval = pcie_port_service_register(&hpdriver_portdrv); |
| pr_debug("pcie_port_service_register = %d\n", retval); |
| if (retval) |
| pr_debug("Failure to register service\n"); |
| |
| return retval; |
| } |