Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2e35afae authored by Alex Williamson's avatar Alex Williamson Committed by Bjorn Helgaas
Browse files

PCI: pciehp: Add reset_slot() method 



PCIe hotplug has a bus per slot, so we can just use a normal
secondary bus reset.  However, if a slot supports surprise removal,
a bus reset can be seen as a presence detection change triggering
a hot-remove followed by a hot-add.  Disable presence detection from
triggering an interrupt or being polled around the bus reset.

Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 5c32b35b

drivers/pci/hotplug/pciehp.h

+1 −0
Original line number Diff line number Diff line
@@ -155,6 +155,7 @@ void pciehp_green_led_off(struct slot *slot); 
void pciehp_green_led_blink(struct slot *slot);

int pciehp_check_link_status(struct controller *ctrl);

void pciehp_release_ctrl(struct controller *ctrl);

int pciehp_reset_slot(struct slot *slot, int probe);



static inline const char *slot_name(struct slot *slot)

{

drivers/pci/hotplug/pciehp_core.c

+12 −0
Original line number Diff line number Diff line
@@ -69,6 +69,7 @@ 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_latch_status	(struct hotplug_slot *slot, u8 *value);

static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);

static int reset_slot		(struct hotplug_slot *slot, int probe);



/**

 * release_slot - free up the memory used by a slot
@@ -111,6 +112,7 @@ static int init_slot(struct controller *ctrl) 
	ops->disable_slot = disable_slot;

	ops->get_power_status = get_power_status;

	ops->get_adapter_status = get_adapter_status;

	ops->reset_slot = reset_slot;

	if (MRL_SENS(ctrl))

		ops->get_latch_status = get_latch_status;

	if (ATTN_LED(ctrl)) {
@@ -223,6 +225,16 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) 
	return pciehp_get_adapter_status(slot, value);

}



static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)

{

	struct slot *slot = hotplug_slot->private;



	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",

		 __func__, slot_name(slot));



	return pciehp_reset_slot(slot, probe);

}



static int pciehp_probe(struct pcie_device *dev)

{

	int rc;

drivers/pci/hotplug/pciehp_hpc.c

+31 −0
Original line number Diff line number Diff line
@@ -749,6 +749,37 @@ static void pcie_disable_notification(struct controller *ctrl) 
		ctrl_warn(ctrl, "Cannot disable software notification\n");

}



/*

 * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary

 * bus reset of the bridge, but if the slot supports surprise removal we need

 * to disable presence detection around the bus reset and clear any spurious

 * events after.

 */

int pciehp_reset_slot(struct slot *slot, int probe)

{

	struct controller *ctrl = slot->ctrl;



	if (probe)

		return 0;



	if (HP_SUPR_RM(ctrl)) {

		pcie_write_cmd(ctrl, 0, PCI_EXP_SLTCTL_PDCE);

		if (pciehp_poll_mode)

			del_timer_sync(&ctrl->poll_timer);

	}



	pci_reset_bridge_secondary_bus(ctrl->pcie->port);



	if (HP_SUPR_RM(ctrl)) {

		pciehp_writew(ctrl, PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDC);

		pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PDCE, PCI_EXP_SLTCTL_PDCE);

		if (pciehp_poll_mode)

			int_poll_timeout(ctrl->poll_timer.data);

	}



	return 0;

}



int pcie_init_notification(struct controller *ctrl)

{

	if (pciehp_request_irq(ctrl))