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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/pci/hotplug/pciehp_core.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/hotplug/pciehp_core.c')
-rw-r--r-- | drivers/pci/hotplug/pciehp_core.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c new file mode 100644 index 000000000..e7fe4b42f --- /dev/null +++ b/drivers/pci/hotplug/pciehp_core.c @@ -0,0 +1,366 @@ +// 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_nested(&ctrl->reset_lock, ctrl->depth); + 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; +} |