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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/pci/hotplug/pciehp_core.c
parentInitial commit. (diff)
downloadlinux-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.c366
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;
+}