1 files changed, 644 insertions, 0 deletions

diff --git a/drivers/pci/hotplug/cpci_hotplug_core.c b/drivers/pci/hotplug/cpci_hotplug_core.c
new file mode 100644
index 000000000..d0559d2fa
--- /dev/null
+++ b/drivers/pci/hotplug/cpci_hotplug_core.c
@@ -0,0 +1,644 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * CompactPCI Hot Plug Driver
+ *
+ * Copyright (C) 2002,2005 SOMA Networks, Inc.
+ * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
+ * Copyright (C) 2001 IBM Corp.
+ *
+ * All rights reserved.
+ *
+ * Send feedback to <scottm@somanetworks.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/pci_hotplug.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/atomic.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include "cpci_hotplug.h"
+
+#define DRIVER_AUTHOR	"Scott Murray <scottm@somanetworks.com>"
+#define DRIVER_DESC	"CompactPCI Hot Plug Core"
+
+#define MY_NAME	"cpci_hotplug"
+
+#define dbg(format, arg...)					\
+	do {							\
+		if (cpci_debug)					\
+			printk(KERN_DEBUG "%s: " format "\n",	\
+				MY_NAME, ## arg);		\
+	} while (0)
+#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
+#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
+#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
+
+/* local variables */
+static DECLARE_RWSEM(list_rwsem);
+static LIST_HEAD(slot_list);
+static int slots;
+static atomic_t extracting;
+int cpci_debug;
+static struct cpci_hp_controller *controller;
+static struct task_struct *cpci_thread;
+static int thread_finished;
+
+static int enable_slot(struct hotplug_slot *slot);
+static int disable_slot(struct hotplug_slot *slot);
+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_attention_status(struct hotplug_slot *slot, u8 *value);
+static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
+static int get_latch_status(struct hotplug_slot *slot, u8 *value);
+
+static const struct hotplug_slot_ops cpci_hotplug_slot_ops = {
+	.enable_slot = enable_slot,
+	.disable_slot = disable_slot,
+	.set_attention_status = set_attention_status,
+	.get_power_status = get_power_status,
+	.get_attention_status = get_attention_status,
+	.get_adapter_status = get_adapter_status,
+	.get_latch_status = get_latch_status,
+};
+
+static int
+enable_slot(struct hotplug_slot *hotplug_slot)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+	int retval = 0;
+
+	dbg("%s - physical_slot = %s", __func__, slot_name(slot));
+
+	if (controller->ops->set_power)
+		retval = controller->ops->set_power(slot, 1);
+	return retval;
+}
+
+static int
+disable_slot(struct hotplug_slot *hotplug_slot)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+	int retval = 0;
+
+	dbg("%s - physical_slot = %s", __func__, slot_name(slot));
+
+	down_write(&list_rwsem);
+
+	/* Unconfigure device */
+	dbg("%s - unconfiguring slot %s", __func__, slot_name(slot));
+	retval = cpci_unconfigure_slot(slot);
+	if (retval) {
+		err("%s - could not unconfigure slot %s",
+		    __func__, slot_name(slot));
+		goto disable_error;
+	}
+	dbg("%s - finished unconfiguring slot %s", __func__, slot_name(slot));
+
+	/* Clear EXT (by setting it) */
+	if (cpci_clear_ext(slot)) {
+		err("%s - could not clear EXT for slot %s",
+		    __func__, slot_name(slot));
+		retval = -ENODEV;
+		goto disable_error;
+	}
+	cpci_led_on(slot);
+
+	if (controller->ops->set_power) {
+		retval = controller->ops->set_power(slot, 0);
+		if (retval)
+			goto disable_error;
+	}
+
+	slot->adapter_status = 0;
+
+	if (slot->extracting) {
+		slot->extracting = 0;
+		atomic_dec(&extracting);
+	}
+disable_error:
+	up_write(&list_rwsem);
+	return retval;
+}
+
+static u8
+cpci_get_power_status(struct slot *slot)
+{
+	u8 power = 1;
+
+	if (controller->ops->get_power)
+		power = controller->ops->get_power(slot);
+	return power;
+}
+
+static int
+get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+
+	*value = cpci_get_power_status(slot);
+	return 0;
+}
+
+static int
+get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+
+	*value = cpci_get_attention_status(slot);
+	return 0;
+}
+
+static int
+set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
+{
+	return cpci_set_attention_status(to_slot(hotplug_slot), status);
+}
+
+static int
+get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+
+	*value = slot->adapter_status;
+	return 0;
+}
+
+static int
+get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = to_slot(hotplug_slot);
+
+	*value = slot->latch_status;
+	return 0;
+}
+
+static void release_slot(struct slot *slot)
+{
+	pci_dev_put(slot->dev);
+	kfree(slot);
+}
+
+#define SLOT_NAME_SIZE	6
+
+int
+cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
+{
+	struct slot *slot;
+	char name[SLOT_NAME_SIZE];
+	int status;
+	int i;
+
+	if (!(controller && bus))
+		return -ENODEV;
+
+	/*
+	 * Create a structure for each slot, and register that slot
+	 * with the pci_hotplug subsystem.
+	 */
+	for (i = first; i <= last; ++i) {
+		slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
+		if (!slot) {
+			status = -ENOMEM;
+			goto error;
+		}
+
+		slot->bus = bus;
+		slot->number = i;
+		slot->devfn = PCI_DEVFN(i, 0);
+
+		snprintf(name, SLOT_NAME_SIZE, "%02x:%02x", bus->number, i);
+
+		slot->hotplug_slot.ops = &cpci_hotplug_slot_ops;
+
+		dbg("registering slot %s", name);
+		status = pci_hp_register(&slot->hotplug_slot, bus, i, name);
+		if (status) {
+			err("pci_hp_register failed with error %d", status);
+			goto error_slot;
+		}
+		dbg("slot registered with name: %s", slot_name(slot));
+
+		/* Add slot to our internal list */
+		down_write(&list_rwsem);
+		list_add(&slot->slot_list, &slot_list);
+		slots++;
+		up_write(&list_rwsem);
+	}
+	return 0;
+error_slot:
+	kfree(slot);
+error:
+	return status;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
+
+int
+cpci_hp_unregister_bus(struct pci_bus *bus)
+{
+	struct slot *slot;
+	struct slot *tmp;
+	int status = 0;
+
+	down_write(&list_rwsem);
+	if (!slots) {
+		up_write(&list_rwsem);
+		return -1;
+	}
+	list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
+		if (slot->bus == bus) {
+			list_del(&slot->slot_list);
+			slots--;
+
+			dbg("deregistering slot %s", slot_name(slot));
+			pci_hp_deregister(&slot->hotplug_slot);
+			release_slot(slot);
+		}
+	}
+	up_write(&list_rwsem);
+	return status;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
+
+/* This is the interrupt mode interrupt handler */
+static irqreturn_t
+cpci_hp_intr(int irq, void *data)
+{
+	dbg("entered cpci_hp_intr");
+
+	/* Check to see if it was our interrupt */
+	if ((controller->irq_flags & IRQF_SHARED) &&
+	    !controller->ops->check_irq(controller->dev_id)) {
+		dbg("exited cpci_hp_intr, not our interrupt");
+		return IRQ_NONE;
+	}
+
+	/* Disable ENUM interrupt */
+	controller->ops->disable_irq();
+
+	/* Trigger processing by the event thread */
+	wake_up_process(cpci_thread);
+	return IRQ_HANDLED;
+}
+
+/*
+ * According to PICMG 2.1 R2.0, section 6.3.2, upon
+ * initialization, the system driver shall clear the
+ * INS bits of the cold-inserted devices.
+ */
+static int
+init_slots(int clear_ins)
+{
+	struct slot *slot;
+	struct pci_dev *dev;
+
+	dbg("%s - enter", __func__);
+	down_read(&list_rwsem);
+	if (!slots) {
+		up_read(&list_rwsem);
+		return -1;
+	}
+	list_for_each_entry(slot, &slot_list, slot_list) {
+		dbg("%s - looking at slot %s", __func__, slot_name(slot));
+		if (clear_ins && cpci_check_and_clear_ins(slot))
+			dbg("%s - cleared INS for slot %s",
+			    __func__, slot_name(slot));
+		dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
+		if (dev) {
+			slot->adapter_status = 1;
+			slot->latch_status = 1;
+			slot->dev = dev;
+		}
+	}
+	up_read(&list_rwsem);
+	dbg("%s - exit", __func__);
+	return 0;
+}
+
+static int
+check_slots(void)
+{
+	struct slot *slot;
+	int extracted;
+	int inserted;
+	u16 hs_csr;
+
+	down_read(&list_rwsem);
+	if (!slots) {
+		up_read(&list_rwsem);
+		err("no slots registered, shutting down");
+		return -1;
+	}
+	extracted = inserted = 0;
+	list_for_each_entry(slot, &slot_list, slot_list) {
+		dbg("%s - looking at slot %s", __func__, slot_name(slot));
+		if (cpci_check_and_clear_ins(slot)) {
+			/*
+			 * Some broken hardware (e.g. PLX 9054AB) asserts
+			 * ENUM# twice...
+			 */
+			if (slot->dev) {
+				warn("slot %s already inserted",
+				     slot_name(slot));
+				inserted++;
+				continue;
+			}
+
+			/* Process insertion */
+			dbg("%s - slot %s inserted", __func__, slot_name(slot));
+
+			/* GSM, debug */
+			hs_csr = cpci_get_hs_csr(slot);
+			dbg("%s - slot %s HS_CSR (1) = %04x",
+			    __func__, slot_name(slot), hs_csr);
+
+			/* Configure device */
+			dbg("%s - configuring slot %s",
+			    __func__, slot_name(slot));
+			if (cpci_configure_slot(slot)) {
+				err("%s - could not configure slot %s",
+				    __func__, slot_name(slot));
+				continue;
+			}
+			dbg("%s - finished configuring slot %s",
+			    __func__, slot_name(slot));
+
+			/* GSM, debug */
+			hs_csr = cpci_get_hs_csr(slot);
+			dbg("%s - slot %s HS_CSR (2) = %04x",
+			    __func__, slot_name(slot), hs_csr);
+
+			slot->latch_status = 1;
+			slot->adapter_status = 1;
+
+			cpci_led_off(slot);
+
+			/* GSM, debug */
+			hs_csr = cpci_get_hs_csr(slot);
+			dbg("%s - slot %s HS_CSR (3) = %04x",
+			    __func__, slot_name(slot), hs_csr);
+
+			inserted++;
+		} else if (cpci_check_ext(slot)) {
+			/* Process extraction request */
+			dbg("%s - slot %s extracted",
+			    __func__, slot_name(slot));
+
+			/* GSM, debug */
+			hs_csr = cpci_get_hs_csr(slot);
+			dbg("%s - slot %s HS_CSR = %04x",
+			    __func__, slot_name(slot), hs_csr);
+
+			if (!slot->extracting) {
+				slot->latch_status = 0;
+				slot->extracting = 1;
+				atomic_inc(&extracting);
+			}
+			extracted++;
+		} else if (slot->extracting) {
+			hs_csr = cpci_get_hs_csr(slot);
+			if (hs_csr == 0xffff) {
+				/*
+				 * Hmmm, we're likely hosed at this point, should we
+				 * bother trying to tell the driver or not?
+				 */
+				err("card in slot %s was improperly removed",
+				    slot_name(slot));
+				slot->adapter_status = 0;
+				slot->extracting = 0;
+				atomic_dec(&extracting);
+			}
+		}
+	}
+	up_read(&list_rwsem);
+	dbg("inserted=%d, extracted=%d, extracting=%d",
+	    inserted, extracted, atomic_read(&extracting));
+	if (inserted || extracted)
+		return extracted;
+	else if (!atomic_read(&extracting)) {
+		err("cannot find ENUM# source, shutting down");
+		return -1;
+	}
+	return 0;
+}
+
+/* This is the interrupt mode worker thread body */
+static int
+event_thread(void *data)
+{
+	int rc;
+
+	dbg("%s - event thread started", __func__);
+	while (1) {
+		dbg("event thread sleeping");
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule();
+		if (kthread_should_stop())
+			break;
+		do {
+			rc = check_slots();
+			if (rc > 0) {
+				/* Give userspace a chance to handle extraction */
+				msleep(500);
+			} else if (rc < 0) {
+				dbg("%s - error checking slots", __func__);
+				thread_finished = 1;
+				goto out;
+			}
+		} while (atomic_read(&extracting) && !kthread_should_stop());
+		if (kthread_should_stop())
+			break;
+
+		/* Re-enable ENUM# interrupt */
+		dbg("%s - re-enabling irq", __func__);
+		controller->ops->enable_irq();
+	}
+ out:
+	return 0;
+}
+
+/* This is the polling mode worker thread body */
+static int
+poll_thread(void *data)
+{
+	int rc;
+
+	while (1) {
+		if (kthread_should_stop() || signal_pending(current))
+			break;
+		if (controller->ops->query_enum()) {
+			do {
+				rc = check_slots();
+				if (rc > 0) {
+					/* Give userspace a chance to handle extraction */
+					msleep(500);
+				} else if (rc < 0) {
+					dbg("%s - error checking slots", __func__);
+					thread_finished = 1;
+					goto out;
+				}
+			} while (atomic_read(&extracting) && !kthread_should_stop());
+		}
+		msleep(100);
+	}
+ out:
+	return 0;
+}
+
+static int
+cpci_start_thread(void)
+{
+	if (controller->irq)
+		cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd");
+	else
+		cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld");
+	if (IS_ERR(cpci_thread)) {
+		err("Can't start up our thread");
+		return PTR_ERR(cpci_thread);
+	}
+	thread_finished = 0;
+	return 0;
+}
+
+static void
+cpci_stop_thread(void)
+{
+	kthread_stop(cpci_thread);
+	thread_finished = 1;
+}
+
+int
+cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
+{
+	int status = 0;
+
+	if (controller)
+		return -1;
+	if (!(new_controller && new_controller->ops))
+		return -EINVAL;
+	if (new_controller->irq) {
+		if (!(new_controller->ops->enable_irq &&
+		     new_controller->ops->disable_irq))
+			status = -EINVAL;
+		if (request_irq(new_controller->irq,
+			       cpci_hp_intr,
+			       new_controller->irq_flags,
+			       MY_NAME,
+			       new_controller->dev_id)) {
+			err("Can't get irq %d for the hotplug cPCI controller",
+			    new_controller->irq);
+			status = -ENODEV;
+		}
+		dbg("%s - acquired controller irq %d",
+		    __func__, new_controller->irq);
+	}
+	if (!status)
+		controller = new_controller;
+	return status;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
+
+static void
+cleanup_slots(void)
+{
+	struct slot *slot;
+	struct slot *tmp;
+
+	/*
+	 * Unregister all of our slots with the pci_hotplug subsystem,
+	 * and free up all memory that we had allocated.
+	 */
+	down_write(&list_rwsem);
+	if (!slots)
+		goto cleanup_null;
+	list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
+		list_del(&slot->slot_list);
+		pci_hp_deregister(&slot->hotplug_slot);
+		release_slot(slot);
+	}
+cleanup_null:
+	up_write(&list_rwsem);
+}
+
+int
+cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
+{
+	int status = 0;
+
+	if (controller) {
+		if (!thread_finished)
+			cpci_stop_thread();
+		if (controller->irq)
+			free_irq(controller->irq, controller->dev_id);
+		controller = NULL;
+		cleanup_slots();
+	} else
+		status = -ENODEV;
+	return status;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
+
+int
+cpci_hp_start(void)
+{
+	static int first = 1;
+	int status;
+
+	dbg("%s - enter", __func__);
+	if (!controller)
+		return -ENODEV;
+
+	down_read(&list_rwsem);
+	if (list_empty(&slot_list)) {
+		up_read(&list_rwsem);
+		return -ENODEV;
+	}
+	up_read(&list_rwsem);
+
+	status = init_slots(first);
+	if (first)
+		first = 0;
+	if (status)
+		return status;
+
+	status = cpci_start_thread();
+	if (status)
+		return status;
+	dbg("%s - thread started", __func__);
+
+	if (controller->irq) {
+		/* Start enum interrupt processing */
+		dbg("%s - enabling irq", __func__);
+		controller->ops->enable_irq();
+	}
+	dbg("%s - exit", __func__);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_start);
+
+int
+cpci_hp_stop(void)
+{
+	if (!controller)
+		return -ENODEV;
+	if (controller->irq) {
+		/* Stop enum interrupt processing */
+		dbg("%s - disabling irq", __func__);
+		controller->ops->disable_irq();
+	}
+	cpci_stop_thread();
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpci_hp_stop);
+
+int __init
+cpci_hotplug_init(int debug)
+{
+	cpci_debug = debug;
+	return 0;
+}