Commit ecdde939 authored by Mark Lord's avatar Mark Lord Committed by Greg Kroah-Hartman
Browse files

PCIe: fix double initialization bug 



Earlier patches to split out the hardware init for PCIe hotplug resulted in
some one-time initializations being redone on every resume cycle.  Eg.
irq/polling initialization.

This patch splits the hardware init into two parts, and separates the
one-time initializations from those so that they only ever get done once,
as intended.

Signed-off-by: default avatarMark Lord <mlord@pobox.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent cd2fe83a

drivers/pci/hotplug/pciehp.h

+1 −1
Original line number Diff line number Diff line
@@ -163,7 +163,7 @@ extern void pciehp_queue_pushbutton_work(struct work_struct *work); 
int pcie_init(struct controller *ctrl, struct pcie_device *dev);

int pciehp_enable_slot(struct slot *p_slot);

int pciehp_disable_slot(struct slot *p_slot);

int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev);

int pcie_init_hardware_part2(struct controller *ctrl, struct pcie_device *dev);



static inline struct slot *pciehp_find_slot(struct controller *ctrl, u8 device)

{

drivers/pci/hotplug/pciehp_core.c

+1 −1
Original line number Diff line number Diff line
@@ -521,7 +521,7 @@ static int pciehp_resume (struct pcie_device *dev) 
		u8 status;



		/* reinitialize the chipset's event detection logic */

		pcie_init_hardware(ctrl, dev);

		pcie_init_hardware_part2(ctrl, dev);



		t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);

drivers/pci/hotplug/pciehp_hpc.c

+67 −52
Original line number Diff line number Diff line
@@ -1067,28 +1067,25 @@ int pciehp_acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev) 
}

#endif



int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev)

static int pcie_init_hardware_part1(struct controller *ctrl,

				    struct pcie_device *dev)

{

	int rc;

	u16 temp_word;

	u16 intr_enable = 0;

	u32 slot_cap;

	u16 slot_status;

	struct pci_dev *pdev;



	pdev = dev->port;



	rc = pciehp_readl(ctrl, SLOTCAP, &slot_cap);

	if (rc) {

		err("%s: Cannot read SLOTCAP register\n", __FUNCTION__);

		goto abort_free_ctlr;

		return -1;

	}



	/* Mask Hot-plug Interrupt Enable */

	rc = pciehp_readw(ctrl, SLOTCTRL, &temp_word);

	if (rc) {

		err("%s: Cannot read SLOTCTRL register\n", __FUNCTION__);

		goto abort_free_ctlr;

		return -1;

	}



	dbg("%s: SLOTCTRL %x value read %x\n",
@@ -1099,62 +1096,46 @@ int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev) 
	rc = pciehp_writew(ctrl, SLOTCTRL, temp_word);

	if (rc) {

		err("%s: Cannot write to SLOTCTRL register\n", __FUNCTION__);

		goto abort_free_ctlr;

		return -1;

	}



	rc = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);

	if (rc) {

		err("%s: Cannot read SLOTSTATUS register\n", __FUNCTION__);

		goto abort_free_ctlr;

		return -1;

	}



	temp_word = 0x1F; /* Clear all events */

	rc = pciehp_writew(ctrl, SLOTSTATUS, temp_word);

	if (rc) {

		err("%s: Cannot write to SLOTSTATUS register\n", __FUNCTION__);

		goto abort_free_ctlr;

	}



	if (pciehp_poll_mode) {

		/* Install interrupt polling timer. Start with 10 sec delay */

		init_timer(&ctrl->poll_timer);

		start_int_poll_timer(ctrl, 10);

	} else {

		/* Installs the interrupt handler */

		rc = request_irq(ctrl->pci_dev->irq, pcie_isr, IRQF_SHARED,

				 MY_NAME, (void *)ctrl);

		dbg("%s: request_irq %d for hpc%d (returns %d)\n",

		    __FUNCTION__, ctrl->pci_dev->irq,

		    atomic_read(&pciehp_num_controllers), rc);

		if (rc) {

			err("Can't get irq %d for the hotplug controller\n",

			    ctrl->pci_dev->irq);

			goto abort_free_ctlr;

		return -1;

	}

	return 0;

}

	dbg("pciehp ctrl b:d:f:irq=0x%x:%x:%x:%x\n", pdev->bus->number,

		PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), dev->irq);



	/*

	 * If this is the first controller to be initialized,

	 * initialize the pciehp work queue

	 */

	if (atomic_add_return(1, &pciehp_num_controllers) == 1) {

		pciehp_wq = create_singlethread_workqueue("pciehpd");

		if (!pciehp_wq) {

			rc = -ENOMEM;

			goto abort_free_irq;

		}

	}

int pcie_init_hardware_part2(struct controller *ctrl, struct pcie_device *dev)

{

	int rc;

	u16 temp_word;

	u16 intr_enable = 0;

	u32 slot_cap;

	u16 slot_status;



	rc = pciehp_readw(ctrl, SLOTCTRL, &temp_word);

	if (rc) {

		err("%s: Cannot read SLOTCTRL register\n", __FUNCTION__);

		goto abort_free_irq;

		goto abort;

	}



	intr_enable = intr_enable | PRSN_DETECT_ENABLE;



	rc = pciehp_readl(ctrl, SLOTCAP, &slot_cap);

	if (rc) {

		err("%s: Cannot read SLOTCAP register\n", __FUNCTION__);

		goto abort;

	}



	if (ATTN_BUTTN(slot_cap))

		intr_enable = intr_enable | ATTN_BUTTN_ENABLE;
@@ -1179,7 +1160,7 @@ int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev) 
	rc = pciehp_writew(ctrl, SLOTCTRL, temp_word);

	if (rc) {

		err("%s: Cannot write to SLOTCTRL register\n", __FUNCTION__);

		goto abort_free_irq;

		goto abort;

	}

	rc = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);

	if (rc) {
@@ -1214,14 +1195,7 @@ abort_disable_intr: 
	}

	if (rc)

		err("%s : disabling interrupts failed\n", __FUNCTION__);



abort_free_irq:

	if (pciehp_poll_mode)

		del_timer_sync(&ctrl->poll_timer);

	else

		free_irq(ctrl->pci_dev->irq, ctrl);



abort_free_ctlr:

abort:

	return -1;

}
@@ -1318,11 +1292,52 @@ int pcie_init(struct controller *ctrl, struct pcie_device *dev) 
	ctrl->first_slot = slot_cap >> 19;

	ctrl->ctrlcap = slot_cap & 0x0000007f;



	rc = pcie_init_hardware(ctrl, dev);

	rc = pcie_init_hardware_part1(ctrl, dev);

	if (rc)

		goto abort;



	if (pciehp_poll_mode) {

		/* Install interrupt polling timer. Start with 10 sec delay */

		init_timer(&ctrl->poll_timer);

		start_int_poll_timer(ctrl, 10);

	} else {

		/* Installs the interrupt handler */

		rc = request_irq(ctrl->pci_dev->irq, pcie_isr, IRQF_SHARED,

				 MY_NAME, (void *)ctrl);

		dbg("%s: request_irq %d for hpc%d (returns %d)\n",

		    __FUNCTION__, ctrl->pci_dev->irq,

		    atomic_read(&pciehp_num_controllers), rc);

		if (rc) {

			err("Can't get irq %d for the hotplug controller\n",

			    ctrl->pci_dev->irq);

			goto abort;

		}

	}

	dbg("pciehp ctrl b:d:f:irq=0x%x:%x:%x:%x\n", pdev->bus->number,

		PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), dev->irq);



	/*

	 * If this is the first controller to be initialized,

	 * initialize the pciehp work queue

	 */

	if (atomic_add_return(1, &pciehp_num_controllers) == 1) {

		pciehp_wq = create_singlethread_workqueue("pciehpd");

		if (!pciehp_wq) {

			rc = -ENOMEM;

			goto abort_free_irq;

		}

	}



	rc = pcie_init_hardware_part2(ctrl, dev);

	if (rc == 0) {

		ctrl->hpc_ops = &pciehp_hpc_ops;

		return 0;

	}

abort_free_irq:

	if (pciehp_poll_mode)

		del_timer_sync(&ctrl->poll_timer);

	else

		free_irq(ctrl->pci_dev->irq, ctrl);

abort:

	return -1;

}

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