1 files changed, 368 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..4042d87d5
--- /dev/null
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -0,0 +1,368 @@
+// 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 */
+
+	.slot_reset	= pciehp_slot_reset,
+};
+
+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;
+}