From 2e35afaefe64946caaecfacaf7fb568e46185e88 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 8 Aug 2013 14:09:37 -0600 Subject: 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: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/hotplug/pciehp.h | 1 + drivers/pci/hotplug/pciehp_core.c | 12 ++++++++++++ drivers/pci/hotplug/pciehp_hpc.c | 31 +++++++++++++++++++++++++++++++ 3 files changed, 44 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 7fb326983ed6..541bbe6d5343 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -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) { diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 7d72c5e2eba9..f4a18f51a29c 100644 --- a/drivers/pci/hotplug/pciehp_core.c +++ b/drivers/pci/hotplug/pciehp_core.c @@ -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; diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index b2255736ac81..51f56ef4ab6f 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -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)) -- cgit v1.2.3