linux/drivers/pci/hotplug/pciehp_hpc.c
Yijing Wang c2be6f93b3 PCI: pciehp: Use per-slot workqueues to avoid deadlock
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.

The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port.  When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method.  That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  pciehp_queue_pushbutton_work
    queue_work(pciehp_wq)                   # queue pciehp_power_thread
    ...

  pciehp_power_thread
    pciehp_disable_slot
      remove_board
	pciehp_unconfigure_device
	  pci_stop_and_remove_bus_device
	    ...
	      pciehp_remove                 # pciehp driver .remove method
		pciehp_release_ctrl
		  pcie_cleanup_slot
		    flush_workqueue(pciehp_wq)

This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.

[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
2013-01-12 13:56:33 -07:00

924 lines
23 KiB
C

/*
* PCI Express PCI Hot Plug 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/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/signal.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/slab.h>
#include "../pci.h"
#include "pciehp.h"
static inline int pciehp_readw(struct controller *ctrl, int reg, u16 *value)
{
struct pci_dev *dev = ctrl->pcie->port;
return pcie_capability_read_word(dev, reg, value);
}
static inline int pciehp_readl(struct controller *ctrl, int reg, u32 *value)
{
struct pci_dev *dev = ctrl->pcie->port;
return pcie_capability_read_dword(dev, reg, value);
}
static inline int pciehp_writew(struct controller *ctrl, int reg, u16 value)
{
struct pci_dev *dev = ctrl->pcie->port;
return pcie_capability_write_word(dev, reg, value);
}
static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value)
{
struct pci_dev *dev = ctrl->pcie->port;
return pcie_capability_write_dword(dev, reg, value);
}
/* Power Control Command */
#define POWER_ON 0
#define POWER_OFF PCI_EXP_SLTCTL_PCC
static irqreturn_t pcie_isr(int irq, void *dev_id);
static void start_int_poll_timer(struct controller *ctrl, int sec);
/* This is the interrupt polling timeout function. */
static void int_poll_timeout(unsigned long data)
{
struct controller *ctrl = (struct controller *)data;
/* Poll for interrupt events. regs == NULL => polling */
pcie_isr(0, ctrl);
init_timer(&ctrl->poll_timer);
if (!pciehp_poll_time)
pciehp_poll_time = 2; /* default polling interval is 2 sec */
start_int_poll_timer(ctrl, pciehp_poll_time);
}
/* This function starts the interrupt polling timer. */
static void start_int_poll_timer(struct controller *ctrl, int sec)
{
/* Clamp to sane value */
if ((sec <= 0) || (sec > 60))
sec = 2;
ctrl->poll_timer.function = &int_poll_timeout;
ctrl->poll_timer.data = (unsigned long)ctrl;
ctrl->poll_timer.expires = jiffies + sec * HZ;
add_timer(&ctrl->poll_timer);
}
static inline int pciehp_request_irq(struct controller *ctrl)
{
int retval, irq = ctrl->pcie->irq;
/* Install interrupt polling timer. Start with 10 sec delay */
if (pciehp_poll_mode) {
init_timer(&ctrl->poll_timer);
start_int_poll_timer(ctrl, 10);
return 0;
}
/* Installs the interrupt handler */
retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl);
if (retval)
ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n",
irq);
return retval;
}
static inline void pciehp_free_irq(struct controller *ctrl)
{
if (pciehp_poll_mode)
del_timer_sync(&ctrl->poll_timer);
else
free_irq(ctrl->pcie->irq, ctrl);
}
static int pcie_poll_cmd(struct controller *ctrl)
{
u16 slot_status;
int err, timeout = 1000;
err = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (!err && (slot_status & PCI_EXP_SLTSTA_CC)) {
pciehp_writew(ctrl, PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_CC);
return 1;
}
while (timeout > 0) {
msleep(10);
timeout -= 10;
err = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (!err && (slot_status & PCI_EXP_SLTSTA_CC)) {
pciehp_writew(ctrl, PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_CC);
return 1;
}
}
return 0; /* timeout */
}
static void pcie_wait_cmd(struct controller *ctrl, int poll)
{
unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
unsigned long timeout = msecs_to_jiffies(msecs);
int rc;
if (poll)
rc = pcie_poll_cmd(ctrl);
else
rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout);
if (!rc)
ctrl_dbg(ctrl, "Command not completed in 1000 msec\n");
}
/**
* pcie_write_cmd - Issue controller command
* @ctrl: controller to which the command is issued
* @cmd: command value written to slot control register
* @mask: bitmask of slot control register to be modified
*/
static int pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
{
int retval = 0;
u16 slot_status;
u16 slot_ctrl;
mutex_lock(&ctrl->ctrl_lock);
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS register\n",
__func__);
goto out;
}
if (slot_status & PCI_EXP_SLTSTA_CC) {
if (!ctrl->no_cmd_complete) {
/*
* After 1 sec and CMD_COMPLETED still not set, just
* proceed forward to issue the next command according
* to spec. Just print out the error message.
*/
ctrl_dbg(ctrl, "CMD_COMPLETED not clear after 1 sec\n");
} else if (!NO_CMD_CMPL(ctrl)) {
/*
* This controller semms to notify of command completed
* event even though it supports none of power
* controller, attention led, power led and EMI.
*/
ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Need to "
"wait for command completed event.\n");
ctrl->no_cmd_complete = 0;
} else {
ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Maybe "
"the controller is broken.\n");
}
}
retval = pciehp_readw(ctrl, PCI_EXP_SLTCTL, &slot_ctrl);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTCTRL register\n", __func__);
goto out;
}
slot_ctrl &= ~mask;
slot_ctrl |= (cmd & mask);
ctrl->cmd_busy = 1;
smp_mb();
retval = pciehp_writew(ctrl, PCI_EXP_SLTCTL, slot_ctrl);
if (retval)
ctrl_err(ctrl, "Cannot write to SLOTCTRL register\n");
/*
* Wait for command completion.
*/
if (!retval && !ctrl->no_cmd_complete) {
int poll = 0;
/*
* if hotplug interrupt is not enabled or command
* completed interrupt is not enabled, we need to poll
* command completed event.
*/
if (!(slot_ctrl & PCI_EXP_SLTCTL_HPIE) ||
!(slot_ctrl & PCI_EXP_SLTCTL_CCIE))
poll = 1;
pcie_wait_cmd(ctrl, poll);
}
out:
mutex_unlock(&ctrl->ctrl_lock);
return retval;
}
static bool check_link_active(struct controller *ctrl)
{
bool ret = false;
u16 lnk_status;
if (pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status))
return ret;
ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
if (ret)
ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
return ret;
}
static void __pcie_wait_link_active(struct controller *ctrl, bool active)
{
int timeout = 1000;
if (check_link_active(ctrl) == active)
return;
while (timeout > 0) {
msleep(10);
timeout -= 10;
if (check_link_active(ctrl) == active)
return;
}
ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
active ? "set" : "cleared");
}
static void pcie_wait_link_active(struct controller *ctrl)
{
__pcie_wait_link_active(ctrl, true);
}
static void pcie_wait_link_not_active(struct controller *ctrl)
{
__pcie_wait_link_active(ctrl, false);
}
static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
{
u32 l;
int count = 0;
int delay = 1000, step = 20;
bool found = false;
do {
found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
count++;
if (found)
break;
msleep(step);
delay -= step;
} while (delay > 0);
if (count > 1 && pciehp_debug)
printk(KERN_DEBUG "pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn), count, step, l);
return found;
}
int pciehp_check_link_status(struct controller *ctrl)
{
u16 lnk_status;
int retval = 0;
bool found = false;
/*
* Data Link Layer Link Active Reporting must be capable for
* hot-plug capable downstream port. But old controller might
* not implement it. In this case, we wait for 1000 ms.
*/
if (ctrl->link_active_reporting)
pcie_wait_link_active(ctrl);
else
msleep(1000);
/* wait 100ms before read pci conf, and try in 1s */
msleep(100);
found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
PCI_DEVFN(0, 0));
retval = pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status);
if (retval) {
ctrl_err(ctrl, "Cannot read LNKSTATUS register\n");
return retval;
}
ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
!(lnk_status & PCI_EXP_LNKSTA_NLW)) {
ctrl_err(ctrl, "Link Training Error occurs \n");
retval = -1;
return retval;
}
pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
if (!found && !retval)
retval = -1;
return retval;
}
static int __pciehp_link_set(struct controller *ctrl, bool enable)
{
u16 lnk_ctrl;
int retval = 0;
retval = pciehp_readw(ctrl, PCI_EXP_LNKCTL, &lnk_ctrl);
if (retval) {
ctrl_err(ctrl, "Cannot read LNKCTRL register\n");
return retval;
}
if (enable)
lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
else
lnk_ctrl |= PCI_EXP_LNKCTL_LD;
retval = pciehp_writew(ctrl, PCI_EXP_LNKCTL, lnk_ctrl);
if (retval) {
ctrl_err(ctrl, "Cannot write LNKCTRL register\n");
return retval;
}
ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
return retval;
}
static int pciehp_link_enable(struct controller *ctrl)
{
return __pciehp_link_set(ctrl, true);
}
static int pciehp_link_disable(struct controller *ctrl)
{
return __pciehp_link_set(ctrl, false);
}
int pciehp_get_attention_status(struct slot *slot, u8 *status)
{
struct controller *ctrl = slot->ctrl;
u16 slot_ctrl;
u8 atten_led_state;
int retval = 0;
retval = pciehp_readw(ctrl, PCI_EXP_SLTCTL, &slot_ctrl);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTCTRL register\n", __func__);
return retval;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
atten_led_state = (slot_ctrl & PCI_EXP_SLTCTL_AIC) >> 6;
switch (atten_led_state) {
case 0:
*status = 0xFF; /* Reserved */
break;
case 1:
*status = 1; /* On */
break;
case 2:
*status = 2; /* Blink */
break;
case 3:
*status = 0; /* Off */
break;
default:
*status = 0xFF;
break;
}
return 0;
}
int pciehp_get_power_status(struct slot *slot, u8 *status)
{
struct controller *ctrl = slot->ctrl;
u16 slot_ctrl;
u8 pwr_state;
int retval = 0;
retval = pciehp_readw(ctrl, PCI_EXP_SLTCTL, &slot_ctrl);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTCTRL register\n", __func__);
return retval;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
pwr_state = (slot_ctrl & PCI_EXP_SLTCTL_PCC) >> 10;
switch (pwr_state) {
case 0:
*status = 1;
break;
case 1:
*status = 0;
break;
default:
*status = 0xFF;
break;
}
return retval;
}
int pciehp_get_latch_status(struct slot *slot, u8 *status)
{
struct controller *ctrl = slot->ctrl;
u16 slot_status;
int retval;
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS register\n",
__func__);
return retval;
}
*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
return 0;
}
int pciehp_get_adapter_status(struct slot *slot, u8 *status)
{
struct controller *ctrl = slot->ctrl;
u16 slot_status;
int retval;
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS register\n",
__func__);
return retval;
}
*status = !!(slot_status & PCI_EXP_SLTSTA_PDS);
return 0;
}
int pciehp_query_power_fault(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_status;
int retval;
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "Cannot check for power fault\n");
return retval;
}
return !!(slot_status & PCI_EXP_SLTSTA_PFD);
}
int pciehp_set_attention_status(struct slot *slot, u8 value)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
cmd_mask = PCI_EXP_SLTCTL_AIC;
switch (value) {
case 0 : /* turn off */
slot_cmd = 0x00C0;
break;
case 1: /* turn on */
slot_cmd = 0x0040;
break;
case 2: /* turn blink */
slot_cmd = 0x0080;
break;
default:
return -EINVAL;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
return pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
}
void pciehp_green_led_on(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
slot_cmd = 0x0100;
cmd_mask = PCI_EXP_SLTCTL_PIC;
pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
}
void pciehp_green_led_off(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
slot_cmd = 0x0300;
cmd_mask = PCI_EXP_SLTCTL_PIC;
pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
}
void pciehp_green_led_blink(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
slot_cmd = 0x0200;
cmd_mask = PCI_EXP_SLTCTL_PIC;
pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
}
int pciehp_power_on_slot(struct slot * slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
u16 slot_status;
int retval = 0;
/* Clear sticky power-fault bit from previous power failures */
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS register\n",
__func__);
return retval;
}
slot_status &= PCI_EXP_SLTSTA_PFD;
if (slot_status) {
retval = pciehp_writew(ctrl, PCI_EXP_SLTSTA, slot_status);
if (retval) {
ctrl_err(ctrl,
"%s: Cannot write to SLOTSTATUS register\n",
__func__);
return retval;
}
}
ctrl->power_fault_detected = 0;
slot_cmd = POWER_ON;
cmd_mask = PCI_EXP_SLTCTL_PCC;
retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
if (retval) {
ctrl_err(ctrl, "Write %x command failed!\n", slot_cmd);
return retval;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
retval = pciehp_link_enable(ctrl);
if (retval)
ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
return retval;
}
int pciehp_power_off_slot(struct slot * slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
int retval;
/* Disable the link at first */
pciehp_link_disable(ctrl);
/* wait the link is down */
if (ctrl->link_active_reporting)
pcie_wait_link_not_active(ctrl);
else
msleep(1000);
slot_cmd = POWER_OFF;
cmd_mask = PCI_EXP_SLTCTL_PCC;
retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
if (retval) {
ctrl_err(ctrl, "Write command failed!\n");
return retval;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
return 0;
}
static irqreturn_t pcie_isr(int irq, void *dev_id)
{
struct controller *ctrl = (struct controller *)dev_id;
struct slot *slot = ctrl->slot;
u16 detected, intr_loc;
/*
* In order to guarantee that all interrupt events are
* serviced, we need to re-inspect Slot Status register after
* clearing what is presumed to be the last pending interrupt.
*/
intr_loc = 0;
do {
if (pciehp_readw(ctrl, PCI_EXP_SLTSTA, &detected)) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS\n",
__func__);
return IRQ_NONE;
}
detected &= (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
PCI_EXP_SLTSTA_CC);
detected &= ~intr_loc;
intr_loc |= detected;
if (!intr_loc)
return IRQ_NONE;
if (detected && pciehp_writew(ctrl, PCI_EXP_SLTSTA, intr_loc)) {
ctrl_err(ctrl, "%s: Cannot write to SLOTSTATUS\n",
__func__);
return IRQ_NONE;
}
} while (detected);
ctrl_dbg(ctrl, "%s: intr_loc %x\n", __func__, intr_loc);
/* Check Command Complete Interrupt Pending */
if (intr_loc & PCI_EXP_SLTSTA_CC) {
ctrl->cmd_busy = 0;
smp_mb();
wake_up(&ctrl->queue);
}
if (!(intr_loc & ~PCI_EXP_SLTSTA_CC))
return IRQ_HANDLED;
/* Check MRL Sensor Changed */
if (intr_loc & PCI_EXP_SLTSTA_MRLSC)
pciehp_handle_switch_change(slot);
/* Check Attention Button Pressed */
if (intr_loc & PCI_EXP_SLTSTA_ABP)
pciehp_handle_attention_button(slot);
/* Check Presence Detect Changed */
if (intr_loc & PCI_EXP_SLTSTA_PDC)
pciehp_handle_presence_change(slot);
/* Check Power Fault Detected */
if ((intr_loc & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
ctrl->power_fault_detected = 1;
pciehp_handle_power_fault(slot);
}
return IRQ_HANDLED;
}
int pcie_enable_notification(struct controller *ctrl)
{
u16 cmd, mask;
/*
* TBD: Power fault detected software notification support.
*
* Power fault detected software notification is not enabled
* now, because it caused power fault detected interrupt storm
* on some machines. On those machines, power fault detected
* bit in the slot status register was set again immediately
* when it is cleared in the interrupt service routine, and
* next power fault detected interrupt was notified again.
*/
cmd = PCI_EXP_SLTCTL_PDCE;
if (ATTN_BUTTN(ctrl))
cmd |= PCI_EXP_SLTCTL_ABPE;
if (MRL_SENS(ctrl))
cmd |= PCI_EXP_SLTCTL_MRLSCE;
if (!pciehp_poll_mode)
cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE);
if (pcie_write_cmd(ctrl, cmd, mask)) {
ctrl_err(ctrl, "Cannot enable software notification\n");
return -1;
}
return 0;
}
static void pcie_disable_notification(struct controller *ctrl)
{
u16 mask;
mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
PCI_EXP_SLTCTL_DLLSCE);
if (pcie_write_cmd(ctrl, 0, mask))
ctrl_warn(ctrl, "Cannot disable software notification\n");
}
int pcie_init_notification(struct controller *ctrl)
{
if (pciehp_request_irq(ctrl))
return -1;
if (pcie_enable_notification(ctrl)) {
pciehp_free_irq(ctrl);
return -1;
}
ctrl->notification_enabled = 1;
return 0;
}
static void pcie_shutdown_notification(struct controller *ctrl)
{
if (ctrl->notification_enabled) {
pcie_disable_notification(ctrl);
pciehp_free_irq(ctrl);
ctrl->notification_enabled = 0;
}
}
static int pcie_init_slot(struct controller *ctrl)
{
struct slot *slot;
char name[32];
slot = kzalloc(sizeof(*slot), GFP_KERNEL);
if (!slot)
return -ENOMEM;
snprintf(name, sizeof(name), "pciehp-%u", PSN(ctrl));
slot->wq = alloc_workqueue(name, 0, 0);
if (!slot->wq)
goto abort;
slot->ctrl = ctrl;
mutex_init(&slot->lock);
INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
ctrl->slot = slot;
return 0;
abort:
kfree(slot);
return -ENOMEM;
}
static void pcie_cleanup_slot(struct controller *ctrl)
{
struct slot *slot = ctrl->slot;
cancel_delayed_work(&slot->work);
destroy_workqueue(slot->wq);
kfree(slot);
}
static inline void dbg_ctrl(struct controller *ctrl)
{
int i;
u16 reg16;
struct pci_dev *pdev = ctrl->pcie->port;
if (!pciehp_debug)
return;
ctrl_info(ctrl, "Hotplug Controller:\n");
ctrl_info(ctrl, " Seg/Bus/Dev/Func/IRQ : %s IRQ %d\n",
pci_name(pdev), pdev->irq);
ctrl_info(ctrl, " Vendor ID : 0x%04x\n", pdev->vendor);
ctrl_info(ctrl, " Device ID : 0x%04x\n", pdev->device);
ctrl_info(ctrl, " Subsystem ID : 0x%04x\n",
pdev->subsystem_device);
ctrl_info(ctrl, " Subsystem Vendor ID : 0x%04x\n",
pdev->subsystem_vendor);
ctrl_info(ctrl, " PCIe Cap offset : 0x%02x\n",
pci_pcie_cap(pdev));
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
if (!pci_resource_len(pdev, i))
continue;
ctrl_info(ctrl, " PCI resource [%d] : %pR\n",
i, &pdev->resource[i]);
}
ctrl_info(ctrl, "Slot Capabilities : 0x%08x\n", ctrl->slot_cap);
ctrl_info(ctrl, " Physical Slot Number : %d\n", PSN(ctrl));
ctrl_info(ctrl, " Attention Button : %3s\n",
ATTN_BUTTN(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " Power Controller : %3s\n",
POWER_CTRL(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " MRL Sensor : %3s\n",
MRL_SENS(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " Attention Indicator : %3s\n",
ATTN_LED(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " Power Indicator : %3s\n",
PWR_LED(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " Hot-Plug Surprise : %3s\n",
HP_SUPR_RM(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " EMI Present : %3s\n",
EMI(ctrl) ? "yes" : "no");
ctrl_info(ctrl, " Command Completed : %3s\n",
NO_CMD_CMPL(ctrl) ? "no" : "yes");
pciehp_readw(ctrl, PCI_EXP_SLTSTA, &reg16);
ctrl_info(ctrl, "Slot Status : 0x%04x\n", reg16);
pciehp_readw(ctrl, PCI_EXP_SLTCTL, &reg16);
ctrl_info(ctrl, "Slot Control : 0x%04x\n", reg16);
}
struct controller *pcie_init(struct pcie_device *dev)
{
struct controller *ctrl;
u32 slot_cap, link_cap;
struct pci_dev *pdev = dev->port;
ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
if (!ctrl) {
dev_err(&dev->device, "%s: Out of memory\n", __func__);
goto abort;
}
ctrl->pcie = dev;
if (pciehp_readl(ctrl, PCI_EXP_SLTCAP, &slot_cap)) {
ctrl_err(ctrl, "Cannot read SLOTCAP register\n");
goto abort_ctrl;
}
ctrl->slot_cap = slot_cap;
mutex_init(&ctrl->ctrl_lock);
init_waitqueue_head(&ctrl->queue);
dbg_ctrl(ctrl);
/*
* Controller doesn't notify of command completion if the "No
* Command Completed Support" bit is set in Slot Capability
* register or the controller supports none of power
* controller, attention led, power led and EMI.
*/
if (NO_CMD_CMPL(ctrl) ||
!(POWER_CTRL(ctrl) | ATTN_LED(ctrl) | PWR_LED(ctrl) | EMI(ctrl)))
ctrl->no_cmd_complete = 1;
/* Check if Data Link Layer Link Active Reporting is implemented */
if (pciehp_readl(ctrl, PCI_EXP_LNKCAP, &link_cap)) {
ctrl_err(ctrl, "%s: Cannot read LNKCAP register\n", __func__);
goto abort_ctrl;
}
if (link_cap & PCI_EXP_LNKCAP_DLLLARC) {
ctrl_dbg(ctrl, "Link Active Reporting supported\n");
ctrl->link_active_reporting = 1;
}
/* Clear all remaining event bits in Slot Status register */
if (pciehp_writew(ctrl, PCI_EXP_SLTSTA, 0x1f))
goto abort_ctrl;
/* Disable sotfware notification */
pcie_disable_notification(ctrl);
ctrl_info(ctrl, "HPC vendor_id %x device_id %x ss_vid %x ss_did %x\n",
pdev->vendor, pdev->device, pdev->subsystem_vendor,
pdev->subsystem_device);
if (pcie_init_slot(ctrl))
goto abort_ctrl;
return ctrl;
abort_ctrl:
kfree(ctrl);
abort:
return NULL;
}
void pciehp_release_ctrl(struct controller *ctrl)
{
pcie_shutdown_notification(ctrl);
pcie_cleanup_slot(ctrl);
kfree(ctrl);
}