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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/pci/hotplug/pciehp_ctrl.c
Initial import
Diffstat (limited to 'drivers/pci/hotplug/pciehp_ctrl.c')
-rw-r--r--drivers/pci/hotplug/pciehp_ctrl.c692
1 files changed, 692 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
new file mode 100644
index 000000000..f052e951b
--- /dev/null
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -0,0 +1,692 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include "../pci.h"
+#include "pciehp.h"
+
+static void interrupt_event_handler(struct work_struct *work);
+
+static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
+{
+ struct event_info *info;
+
+ info = kmalloc(sizeof(*info), GFP_ATOMIC);
+ if (!info)
+ return -ENOMEM;
+
+ info->event_type = event_type;
+ info->p_slot = p_slot;
+ INIT_WORK(&info->work, interrupt_event_handler);
+
+ queue_work(p_slot->wq, &info->work);
+
+ return 0;
+}
+
+u8 pciehp_handle_attention_button(struct slot *p_slot)
+{
+ u32 event_type;
+ struct controller *ctrl = p_slot->ctrl;
+
+ /* Attention Button Change */
+ ctrl_dbg(ctrl, "Attention button interrupt received\n");
+
+ /*
+ * Button pressed - See if need to TAKE ACTION!!!
+ */
+ ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
+ event_type = INT_BUTTON_PRESS;
+
+ queue_interrupt_event(p_slot, event_type);
+
+ return 0;
+}
+
+u8 pciehp_handle_switch_change(struct slot *p_slot)
+{
+ u8 getstatus;
+ u32 event_type;
+ struct controller *ctrl = p_slot->ctrl;
+
+ /* Switch Change */
+ ctrl_dbg(ctrl, "Switch interrupt received\n");
+
+ pciehp_get_latch_status(p_slot, &getstatus);
+ if (getstatus) {
+ /*
+ * Switch opened
+ */
+ ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
+ event_type = INT_SWITCH_OPEN;
+ } else {
+ /*
+ * Switch closed
+ */
+ ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
+ event_type = INT_SWITCH_CLOSE;
+ }
+
+ queue_interrupt_event(p_slot, event_type);
+
+ return 1;
+}
+
+u8 pciehp_handle_presence_change(struct slot *p_slot)
+{
+ u32 event_type;
+ u8 presence_save;
+ struct controller *ctrl = p_slot->ctrl;
+
+ /* Presence Change */
+ ctrl_dbg(ctrl, "Presence/Notify input change\n");
+
+ /* Switch is open, assume a presence change
+ * Save the presence state
+ */
+ pciehp_get_adapter_status(p_slot, &presence_save);
+ if (presence_save) {
+ /*
+ * Card Present
+ */
+ ctrl_info(ctrl, "Card present on Slot(%s)\n", slot_name(p_slot));
+ event_type = INT_PRESENCE_ON;
+ } else {
+ /*
+ * Not Present
+ */
+ ctrl_info(ctrl, "Card not present on Slot(%s)\n",
+ slot_name(p_slot));
+ event_type = INT_PRESENCE_OFF;
+ }
+
+ queue_interrupt_event(p_slot, event_type);
+
+ return 1;
+}
+
+u8 pciehp_handle_power_fault(struct slot *p_slot)
+{
+ u32 event_type;
+ struct controller *ctrl = p_slot->ctrl;
+
+ /* power fault */
+ ctrl_dbg(ctrl, "Power fault interrupt received\n");
+ ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
+ event_type = INT_POWER_FAULT;
+ ctrl_info(ctrl, "Power fault bit %x set\n", 0);
+ queue_interrupt_event(p_slot, event_type);
+
+ return 1;
+}
+
+void pciehp_handle_linkstate_change(struct slot *p_slot)
+{
+ u32 event_type;
+ struct controller *ctrl = p_slot->ctrl;
+
+ /* Link Status Change */
+ ctrl_dbg(ctrl, "Data Link Layer State change\n");
+
+ if (pciehp_check_link_active(ctrl)) {
+ ctrl_info(ctrl, "slot(%s): Link Up event\n",
+ slot_name(p_slot));
+ event_type = INT_LINK_UP;
+ } else {
+ ctrl_info(ctrl, "slot(%s): Link Down event\n",
+ slot_name(p_slot));
+ event_type = INT_LINK_DOWN;
+ }
+
+ queue_interrupt_event(p_slot, event_type);
+}
+
+/* The following routines constitute the bulk of the
+ hotplug controller logic
+ */
+
+static void set_slot_off(struct controller *ctrl, struct slot *pslot)
+{
+ /* turn off slot, turn on Amber LED, turn off Green LED if supported*/
+ if (POWER_CTRL(ctrl)) {
+ pciehp_power_off_slot(pslot);
+
+ /*
+ * After turning power off, we must wait for at least 1 second
+ * before taking any action that relies on power having been
+ * removed from the slot/adapter.
+ */
+ msleep(1000);
+ }
+
+ pciehp_green_led_off(pslot);
+ pciehp_set_attention_status(pslot, 1);
+}
+
+/**
+ * board_added - Called after a board has been added to the system.
+ * @p_slot: &slot where board is added
+ *
+ * Turns power on for the board.
+ * Configures board.
+ */
+static int board_added(struct slot *p_slot)
+{
+ int retval = 0;
+ struct controller *ctrl = p_slot->ctrl;
+ struct pci_bus *parent = ctrl->pcie->port->subordinate;
+
+ if (POWER_CTRL(ctrl)) {
+ /* Power on slot */
+ retval = pciehp_power_on_slot(p_slot);
+ if (retval)
+ return retval;
+ }
+
+ pciehp_green_led_blink(p_slot);
+
+ /* Check link training status */
+ retval = pciehp_check_link_status(ctrl);
+ if (retval) {
+ ctrl_err(ctrl, "Failed to check link status\n");
+ goto err_exit;
+ }
+
+ /* Check for a power fault */
+ if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
+ ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
+ retval = -EIO;
+ goto err_exit;
+ }
+
+ retval = pciehp_configure_device(p_slot);
+ if (retval) {
+ ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
+ pci_domain_nr(parent), parent->number);
+ if (retval != -EEXIST)
+ goto err_exit;
+ }
+
+ pciehp_green_led_on(p_slot);
+ return 0;
+
+err_exit:
+ set_slot_off(ctrl, p_slot);
+ return retval;
+}
+
+/**
+ * remove_board - Turns off slot and LEDs
+ * @p_slot: slot where board is being removed
+ */
+static int remove_board(struct slot *p_slot)
+{
+ int retval;
+ struct controller *ctrl = p_slot->ctrl;
+
+ retval = pciehp_unconfigure_device(p_slot);
+ if (retval)
+ return retval;
+
+ if (POWER_CTRL(ctrl)) {
+ pciehp_power_off_slot(p_slot);
+
+ /*
+ * After turning power off, we must wait for at least 1 second
+ * before taking any action that relies on power having been
+ * removed from the slot/adapter.
+ */
+ msleep(1000);
+ }
+
+ /* turn off Green LED */
+ pciehp_green_led_off(p_slot);
+ return 0;
+}
+
+struct power_work_info {
+ struct slot *p_slot;
+ struct work_struct work;
+ unsigned int req;
+#define DISABLE_REQ 0
+#define ENABLE_REQ 1
+};
+
+/**
+ * pciehp_power_thread - handle pushbutton events
+ * @work: &struct work_struct describing work to be done
+ *
+ * Scheduled procedure to handle blocking stuff for the pushbuttons.
+ * Handles all pending events and exits.
+ */
+static void pciehp_power_thread(struct work_struct *work)
+{
+ struct power_work_info *info =
+ container_of(work, struct power_work_info, work);
+ struct slot *p_slot = info->p_slot;
+ int ret;
+
+ switch (info->req) {
+ case DISABLE_REQ:
+ ctrl_dbg(p_slot->ctrl,
+ "Disabling domain:bus:device=%04x:%02x:00\n",
+ pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
+ p_slot->ctrl->pcie->port->subordinate->number);
+ mutex_lock(&p_slot->hotplug_lock);
+ pciehp_disable_slot(p_slot);
+ mutex_unlock(&p_slot->hotplug_lock);
+ mutex_lock(&p_slot->lock);
+ p_slot->state = STATIC_STATE;
+ mutex_unlock(&p_slot->lock);
+ break;
+ case ENABLE_REQ:
+ ctrl_dbg(p_slot->ctrl,
+ "Enabling domain:bus:device=%04x:%02x:00\n",
+ pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
+ p_slot->ctrl->pcie->port->subordinate->number);
+ mutex_lock(&p_slot->hotplug_lock);
+ ret = pciehp_enable_slot(p_slot);
+ mutex_unlock(&p_slot->hotplug_lock);
+ if (ret)
+ pciehp_green_led_off(p_slot);
+ mutex_lock(&p_slot->lock);
+ p_slot->state = STATIC_STATE;
+ mutex_unlock(&p_slot->lock);
+ break;
+ default:
+ break;
+ }
+
+ kfree(info);
+}
+
+void pciehp_queue_pushbutton_work(struct work_struct *work)
+{
+ struct slot *p_slot = container_of(work, struct slot, work.work);
+ struct power_work_info *info;
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
+ __func__);
+ return;
+ }
+ info->p_slot = p_slot;
+ INIT_WORK(&info->work, pciehp_power_thread);
+
+ mutex_lock(&p_slot->lock);
+ switch (p_slot->state) {
+ case BLINKINGOFF_STATE:
+ p_slot->state = POWEROFF_STATE;
+ info->req = DISABLE_REQ;
+ break;
+ case BLINKINGON_STATE:
+ p_slot->state = POWERON_STATE;
+ info->req = ENABLE_REQ;
+ break;
+ default:
+ kfree(info);
+ goto out;
+ }
+ queue_work(p_slot->wq, &info->work);
+ out:
+ mutex_unlock(&p_slot->lock);
+}
+
+/*
+ * Note: This function must be called with slot->lock held
+ */
+static void handle_button_press_event(struct slot *p_slot)
+{
+ struct controller *ctrl = p_slot->ctrl;
+ u8 getstatus;
+
+ switch (p_slot->state) {
+ case STATIC_STATE:
+ pciehp_get_power_status(p_slot, &getstatus);
+ if (getstatus) {
+ p_slot->state = BLINKINGOFF_STATE;
+ ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
+ slot_name(p_slot));
+ } else {
+ p_slot->state = BLINKINGON_STATE;
+ ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
+ slot_name(p_slot));
+ }
+ /* blink green LED and turn off amber */
+ pciehp_green_led_blink(p_slot);
+ pciehp_set_attention_status(p_slot, 0);
+ queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
+ break;
+ case BLINKINGOFF_STATE:
+ case BLINKINGON_STATE:
+ /*
+ * Cancel if we are still blinking; this means that we
+ * press the attention again before the 5 sec. limit
+ * expires to cancel hot-add or hot-remove
+ */
+ ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
+ cancel_delayed_work(&p_slot->work);
+ if (p_slot->state == BLINKINGOFF_STATE)
+ pciehp_green_led_on(p_slot);
+ else
+ pciehp_green_led_off(p_slot);
+ pciehp_set_attention_status(p_slot, 0);
+ ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
+ slot_name(p_slot));
+ p_slot->state = STATIC_STATE;
+ break;
+ case POWEROFF_STATE:
+ case POWERON_STATE:
+ /*
+ * Ignore if the slot is on power-on or power-off state;
+ * this means that the previous attention button action
+ * to hot-add or hot-remove is undergoing
+ */
+ ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
+ break;
+ default:
+ ctrl_warn(ctrl, "Not a valid state\n");
+ break;
+ }
+}
+
+/*
+ * Note: This function must be called with slot->lock held
+ */
+static void handle_surprise_event(struct slot *p_slot)
+{
+ u8 getstatus;
+ struct power_work_info *info;
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
+ __func__);
+ return;
+ }
+ info->p_slot = p_slot;
+ INIT_WORK(&info->work, pciehp_power_thread);
+
+ pciehp_get_adapter_status(p_slot, &getstatus);
+ if (!getstatus) {
+ p_slot->state = POWEROFF_STATE;
+ info->req = DISABLE_REQ;
+ } else {
+ p_slot->state = POWERON_STATE;
+ info->req = ENABLE_REQ;
+ }
+
+ queue_work(p_slot->wq, &info->work);
+}
+
+/*
+ * Note: This function must be called with slot->lock held
+ */
+static void handle_link_event(struct slot *p_slot, u32 event)
+{
+ struct controller *ctrl = p_slot->ctrl;
+ struct power_work_info *info;
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
+ __func__);
+ return;
+ }
+ info->p_slot = p_slot;
+ info->req = event == INT_LINK_UP ? ENABLE_REQ : DISABLE_REQ;
+ INIT_WORK(&info->work, pciehp_power_thread);
+
+ switch (p_slot->state) {
+ case BLINKINGON_STATE:
+ case BLINKINGOFF_STATE:
+ cancel_delayed_work(&p_slot->work);
+ /* Fall through */
+ case STATIC_STATE:
+ p_slot->state = event == INT_LINK_UP ?
+ POWERON_STATE : POWEROFF_STATE;
+ queue_work(p_slot->wq, &info->work);
+ break;
+ case POWERON_STATE:
+ if (event == INT_LINK_UP) {
+ ctrl_info(ctrl,
+ "Link Up event ignored on slot(%s): already powering on\n",
+ slot_name(p_slot));
+ kfree(info);
+ } else {
+ ctrl_info(ctrl,
+ "Link Down event queued on slot(%s): currently getting powered on\n",
+ slot_name(p_slot));
+ p_slot->state = POWEROFF_STATE;
+ queue_work(p_slot->wq, &info->work);
+ }
+ break;
+ case POWEROFF_STATE:
+ if (event == INT_LINK_UP) {
+ ctrl_info(ctrl,
+ "Link Up event queued on slot(%s): currently getting powered off\n",
+ slot_name(p_slot));
+ p_slot->state = POWERON_STATE;
+ queue_work(p_slot->wq, &info->work);
+ } else {
+ ctrl_info(ctrl,
+ "Link Down event ignored on slot(%s): already powering off\n",
+ slot_name(p_slot));
+ kfree(info);
+ }
+ break;
+ default:
+ ctrl_err(ctrl, "Not a valid state on slot(%s)\n",
+ slot_name(p_slot));
+ kfree(info);
+ break;
+ }
+}
+
+static void interrupt_event_handler(struct work_struct *work)
+{
+ struct event_info *info = container_of(work, struct event_info, work);
+ struct slot *p_slot = info->p_slot;
+ struct controller *ctrl = p_slot->ctrl;
+
+ mutex_lock(&p_slot->lock);
+ switch (info->event_type) {
+ case INT_BUTTON_PRESS:
+ handle_button_press_event(p_slot);
+ break;
+ case INT_POWER_FAULT:
+ if (!POWER_CTRL(ctrl))
+ break;
+ pciehp_set_attention_status(p_slot, 1);
+ pciehp_green_led_off(p_slot);
+ break;
+ case INT_PRESENCE_ON:
+ ctrl_dbg(ctrl, "Surprise Insertion\n");
+ handle_surprise_event(p_slot);
+ break;
+ case INT_PRESENCE_OFF:
+ /*
+ * Regardless of surprise capability, we need to
+ * definitely remove a card that has been pulled out!
+ */
+ ctrl_dbg(ctrl, "Surprise Removal\n");
+ handle_surprise_event(p_slot);
+ break;
+ case INT_LINK_UP:
+ case INT_LINK_DOWN:
+ handle_link_event(p_slot, info->event_type);
+ break;
+ default:
+ break;
+ }
+ mutex_unlock(&p_slot->lock);
+
+ kfree(info);
+}
+
+/*
+ * Note: This function must be called with slot->hotplug_lock held
+ */
+int pciehp_enable_slot(struct slot *p_slot)
+{
+ u8 getstatus = 0;
+ int rc;
+ struct controller *ctrl = p_slot->ctrl;
+
+ pciehp_get_adapter_status(p_slot, &getstatus);
+ if (!getstatus) {
+ ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
+ return -ENODEV;
+ }
+ if (MRL_SENS(p_slot->ctrl)) {
+ pciehp_get_latch_status(p_slot, &getstatus);
+ if (getstatus) {
+ ctrl_info(ctrl, "Latch open on slot(%s)\n",
+ slot_name(p_slot));
+ return -ENODEV;
+ }
+ }
+
+ if (POWER_CTRL(p_slot->ctrl)) {
+ pciehp_get_power_status(p_slot, &getstatus);
+ if (getstatus) {
+ ctrl_info(ctrl, "Already enabled on slot(%s)\n",
+ slot_name(p_slot));
+ return -EINVAL;
+ }
+ }
+
+ pciehp_get_latch_status(p_slot, &getstatus);
+
+ rc = board_added(p_slot);
+ if (rc)
+ pciehp_get_latch_status(p_slot, &getstatus);
+
+ return rc;
+}
+
+/*
+ * Note: This function must be called with slot->hotplug_lock held
+ */
+int pciehp_disable_slot(struct slot *p_slot)
+{
+ u8 getstatus = 0;
+ struct controller *ctrl = p_slot->ctrl;
+
+ if (!p_slot->ctrl)
+ return 1;
+
+ if (POWER_CTRL(p_slot->ctrl)) {
+ pciehp_get_power_status(p_slot, &getstatus);
+ if (!getstatus) {
+ ctrl_info(ctrl, "Already disabled on slot(%s)\n",
+ slot_name(p_slot));
+ return -EINVAL;
+ }
+ }
+
+ return remove_board(p_slot);
+}
+
+int pciehp_sysfs_enable_slot(struct slot *p_slot)
+{
+ int retval = -ENODEV;
+ struct controller *ctrl = p_slot->ctrl;
+
+ mutex_lock(&p_slot->lock);
+ switch (p_slot->state) {
+ case BLINKINGON_STATE:
+ cancel_delayed_work(&p_slot->work);
+ case STATIC_STATE:
+ p_slot->state = POWERON_STATE;
+ mutex_unlock(&p_slot->lock);
+ mutex_lock(&p_slot->hotplug_lock);
+ retval = pciehp_enable_slot(p_slot);
+ mutex_unlock(&p_slot->hotplug_lock);
+ mutex_lock(&p_slot->lock);
+ p_slot->state = STATIC_STATE;
+ break;
+ case POWERON_STATE:
+ ctrl_info(ctrl, "Slot %s is already in powering on state\n",
+ slot_name(p_slot));
+ break;
+ case BLINKINGOFF_STATE:
+ case POWEROFF_STATE:
+ ctrl_info(ctrl, "Already enabled on slot %s\n",
+ slot_name(p_slot));
+ break;
+ default:
+ ctrl_err(ctrl, "Not a valid state on slot %s\n",
+ slot_name(p_slot));
+ break;
+ }
+ mutex_unlock(&p_slot->lock);
+
+ return retval;
+}
+
+int pciehp_sysfs_disable_slot(struct slot *p_slot)
+{
+ int retval = -ENODEV;
+ struct controller *ctrl = p_slot->ctrl;
+
+ mutex_lock(&p_slot->lock);
+ switch (p_slot->state) {
+ case BLINKINGOFF_STATE:
+ cancel_delayed_work(&p_slot->work);
+ case STATIC_STATE:
+ p_slot->state = POWEROFF_STATE;
+ mutex_unlock(&p_slot->lock);
+ retval = pciehp_disable_slot(p_slot);
+ mutex_lock(&p_slot->lock);
+ p_slot->state = STATIC_STATE;
+ break;
+ case POWEROFF_STATE:
+ ctrl_info(ctrl, "Slot %s is already in powering off state\n",
+ slot_name(p_slot));
+ break;
+ case BLINKINGON_STATE:
+ case POWERON_STATE:
+ ctrl_info(ctrl, "Already disabled on slot %s\n",
+ slot_name(p_slot));
+ break;
+ default:
+ ctrl_err(ctrl, "Not a valid state on slot %s\n",
+ slot_name(p_slot));
+ break;
+ }
+ mutex_unlock(&p_slot->lock);
+
+ return retval;
+}