diff options
Diffstat (limited to 'drivers/pci/hotplug/pciehp.h')
| -rw-r--r-- | drivers/pci/hotplug/pciehp.h | 117 |
1 files changed, 91 insertions, 26 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 5f892065585e..811cf83f956d 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -21,6 +21,7 @@ #include <linux/delay.h> #include <linux/sched/signal.h> /* signal_pending() */ #include <linux/mutex.h> +#include <linux/rwsem.h> #include <linux/workqueue.h> #include "../pcie/portdrv.h" @@ -57,49 +58,111 @@ do { \ dev_warn(&ctrl->pcie->device, format, ## arg) #define SLOT_NAME_SIZE 10 + +/** + * struct slot - PCIe hotplug slot + * @state: current state machine position + * @ctrl: pointer to the slot's controller structure + * @hotplug_slot: pointer to the structure registered with the PCI hotplug core + * @work: work item to turn the slot on or off after 5 seconds in response to + * an Attention Button press + * @lock: protects reads and writes of @state; + * protects scheduling, execution and cancellation of @work + */ struct slot { u8 state; struct controller *ctrl; struct hotplug_slot *hotplug_slot; - struct delayed_work work; /* work for button event */ + struct delayed_work work; struct mutex lock; - struct mutex hotplug_lock; - struct workqueue_struct *wq; -}; - -struct event_info { - u32 event_type; - struct slot *p_slot; - struct work_struct work; }; +/** + * struct controller - PCIe hotplug controller + * @ctrl_lock: serializes writes to the Slot Control register + * @pcie: pointer to the controller's PCIe port service device + * @reset_lock: prevents access to the Data Link Layer Link Active bit in the + * Link Status register and to the Presence Detect State bit in the Slot + * Status register during a slot reset which may cause them to flap + * @slot: pointer to the controller's slot structure + * @queue: wait queue to wake up on reception of a Command Completed event, + * used for synchronous writes to the Slot Control register + * @slot_cap: cached copy of the Slot Capabilities register + * @slot_ctrl: cached copy of the Slot Control register + * @poll_thread: thread to poll for slot events if no IRQ is available, + * enabled with pciehp_poll_mode module parameter + * @cmd_started: jiffies when the Slot Control register was last written; + * the next write is allowed 1 second later, absent a Command Completed + * interrupt (PCIe r4.0, sec 6.7.3.2) + * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler + * on reception of a Command Completed event + * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting + * Capable bit in Link Capabilities register; if this bit is zero, the + * Data Link Layer Link Active bit in the Link Status register will never + * be set and the driver is thus confined to wait 1 second before assuming + * the link to a hotplugged device is up and accessing it + * @notification_enabled: whether the IRQ was requested successfully + * @power_fault_detected: whether a power fault was detected by the hardware + * that has not yet been cleared by the user + * @pending_events: used by the IRQ handler to save events retrieved from the + * Slot Status register for later consumption by the IRQ thread + * @request_result: result of last user request submitted to the IRQ thread + * @requester: wait queue to wake up on completion of user request, + * used for synchronous slot enable/disable request via sysfs + */ struct controller { - struct mutex ctrl_lock; /* controller lock */ - struct pcie_device *pcie; /* PCI Express port service */ + struct mutex ctrl_lock; + struct pcie_device *pcie; + struct rw_semaphore reset_lock; struct slot *slot; - wait_queue_head_t queue; /* sleep & wake process */ + wait_queue_head_t queue; u32 slot_cap; u16 slot_ctrl; - struct timer_list poll_timer; + struct task_struct *poll_thread; unsigned long cmd_started; /* jiffies */ unsigned int cmd_busy:1; unsigned int link_active_reporting:1; unsigned int notification_enabled:1; unsigned int power_fault_detected; + atomic_t pending_events; + int request_result; + wait_queue_head_t requester; }; -#define INT_PRESENCE_ON 1 -#define INT_PRESENCE_OFF 2 -#define INT_POWER_FAULT 3 -#define INT_BUTTON_PRESS 4 -#define INT_LINK_UP 5 -#define INT_LINK_DOWN 6 - -#define STATIC_STATE 0 +/** + * DOC: Slot state + * + * @OFF_STATE: slot is powered off, no subordinate devices are enumerated + * @BLINKINGON_STATE: slot will be powered on after the 5 second delay, + * green led is blinking + * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay, + * green led is blinking + * @POWERON_STATE: slot is currently powering on + * @POWEROFF_STATE: slot is currently powering off + * @ON_STATE: slot is powered on, subordinate devices have been enumerated + */ +#define OFF_STATE 0 #define BLINKINGON_STATE 1 #define BLINKINGOFF_STATE 2 #define POWERON_STATE 3 #define POWEROFF_STATE 4 +#define ON_STATE 5 + +/** + * DOC: Flags to request an action from the IRQ thread + * + * These are stored together with events read from the Slot Status register, + * hence must be greater than its 16-bit width. + * + * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or + * an Attention Button press after the 5 second delay + * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the + * hotplug port was inaccessible when the interrupt occurred, requiring + * that the IRQ handler is rerun by the IRQ thread after it has made the + * hotplug port accessible by runtime resuming its parents to D0 + */ +#define DISABLE_SLOT (1 << 16) +#define RERUN_ISR (1 << 17) #define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP) #define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP) @@ -113,15 +176,17 @@ struct controller { int pciehp_sysfs_enable_slot(struct slot *slot); int pciehp_sysfs_disable_slot(struct slot *slot); -void pciehp_queue_interrupt_event(struct slot *slot, u32 event_type); +void pciehp_request(struct controller *ctrl, int action); +void pciehp_handle_button_press(struct slot *slot); +void pciehp_handle_disable_request(struct slot *slot); +void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events); int pciehp_configure_device(struct slot *p_slot); -int pciehp_unconfigure_device(struct slot *p_slot); +void pciehp_unconfigure_device(struct slot *p_slot); void pciehp_queue_pushbutton_work(struct work_struct *work); struct controller *pcie_init(struct pcie_device *dev); int pcie_init_notification(struct controller *ctrl); -int pciehp_enable_slot(struct slot *p_slot); -int pciehp_disable_slot(struct slot *p_slot); -void pcie_reenable_notification(struct controller *ctrl); +void pcie_shutdown_notification(struct controller *ctrl); +void pcie_clear_hotplug_events(struct controller *ctrl); int pciehp_power_on_slot(struct slot *slot); void pciehp_power_off_slot(struct slot *slot); void pciehp_get_power_status(struct slot *slot, u8 *status); |