diff options
Diffstat (limited to 'drivers/pci/hotplug/pciehp.h')
| -rw-r--r-- | drivers/pci/hotplug/pciehp.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h new file mode 100644 index 000000000..e0a614ace --- /dev/null +++ b/drivers/pci/hotplug/pciehp.h @@ -0,0 +1,207 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * PCI Express Hot Plug Controller 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. + * + * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com> + * + */ +#ifndef _PCIEHP_H +#define _PCIEHP_H + +#include <linux/types.h> +#include <linux/pci.h> +#include <linux/pci_hotplug.h> +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/rwsem.h> +#include <linux/workqueue.h> + +#include "../pcie/portdrv.h" + +extern bool pciehp_poll_mode; +extern int pciehp_poll_time; + +/* + * Set CONFIG_DYNAMIC_DEBUG=y and boot with 'dyndbg="file pciehp* +p"' to + * enable debug messages. + */ +#define ctrl_dbg(ctrl, format, arg...) \ + pci_dbg(ctrl->pcie->port, format, ## arg) +#define ctrl_err(ctrl, format, arg...) \ + pci_err(ctrl->pcie->port, format, ## arg) +#define ctrl_info(ctrl, format, arg...) \ + pci_info(ctrl->pcie->port, format, ## arg) +#define ctrl_warn(ctrl, format, arg...) \ + pci_warn(ctrl->pcie->port, format, ## arg) + +#define SLOT_NAME_SIZE 10 + +/** + * struct controller - PCIe hotplug controller + * @pcie: pointer to the controller's PCIe port service device + * @slot_cap: cached copy of the Slot Capabilities register + * @inband_presence_disabled: In-Band Presence Detect Disable supported by + * controller and disabled per spec recommendation (PCIe r5.0, appendix I + * implementation note) + * @slot_ctrl: cached copy of the Slot Control register + * @ctrl_lock: serializes writes to the Slot Control register + * @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 + * @queue: wait queue to wake up on reception of a Command Completed event, + * used for synchronous writes to the Slot Control register + * @pending_events: used by the IRQ handler to save events retrieved from the + * Slot Status register for later consumption by the IRQ thread + * @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 + * @poll_thread: thread to poll for slot events if no IRQ is available, + * enabled with pciehp_poll_mode module parameter + * @state: current state machine position + * @state_lock: protects reads and writes of @state; + * protects scheduling, execution and cancellation of @button_work + * @button_work: work item to turn the slot on or off after 5 seconds + * in response to an Attention Button press + * @hotplug_slot: structure registered with the PCI hotplug core + * @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 + * @depth: Number of additional hotplug ports in the path to the root bus, + * used as lock subclass for @reset_lock + * @ist_running: flag to keep user request waiting while IRQ thread is running + * @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 + * + * PCIe hotplug has a 1:1 relationship between controller and slot, hence + * unlike other drivers, the two aren't represented by separate structures. + */ +struct controller { + struct pcie_device *pcie; + + u32 slot_cap; /* capabilities and quirks */ + unsigned int inband_presence_disabled:1; + + u16 slot_ctrl; /* control register access */ + struct mutex ctrl_lock; + unsigned long cmd_started; + unsigned int cmd_busy:1; + wait_queue_head_t queue; + + atomic_t pending_events; /* event handling */ + unsigned int notification_enabled:1; + unsigned int power_fault_detected; + struct task_struct *poll_thread; + + u8 state; /* state machine */ + struct mutex state_lock; + struct delayed_work button_work; + + struct hotplug_slot hotplug_slot; /* hotplug core interface */ + struct rw_semaphore reset_lock; + unsigned int depth; + unsigned int ist_running; + int request_result; + wait_queue_head_t requester; +}; + +/** + * 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, + * Power Indicator is blinking + * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay, + * Power Indicator 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) +#define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP) +#define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP) +#define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP) +#define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS) +#define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19) + +void pciehp_request(struct controller *ctrl, int action); +void pciehp_handle_button_press(struct controller *ctrl); +void pciehp_handle_disable_request(struct controller *ctrl); +void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events); +int pciehp_configure_device(struct controller *ctrl); +void pciehp_unconfigure_device(struct controller *ctrl, bool presence); +void pciehp_queue_pushbutton_work(struct work_struct *work); +struct controller *pcie_init(struct pcie_device *dev); +int pcie_init_notification(struct controller *ctrl); +void pcie_shutdown_notification(struct controller *ctrl); +void pcie_clear_hotplug_events(struct controller *ctrl); +void pcie_enable_interrupt(struct controller *ctrl); +void pcie_disable_interrupt(struct controller *ctrl); +int pciehp_power_on_slot(struct controller *ctrl); +void pciehp_power_off_slot(struct controller *ctrl); +void pciehp_get_power_status(struct controller *ctrl, u8 *status); + +#define INDICATOR_NOOP -1 /* Leave indicator unchanged */ +void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn); + +void pciehp_get_latch_status(struct controller *ctrl, u8 *status); +int pciehp_query_power_fault(struct controller *ctrl); +int pciehp_card_present(struct controller *ctrl); +int pciehp_card_present_or_link_active(struct controller *ctrl); +int pciehp_check_link_status(struct controller *ctrl); +int pciehp_check_link_active(struct controller *ctrl); +void pciehp_release_ctrl(struct controller *ctrl); + +int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot); +int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot); +int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe); +int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status); +int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status); +int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status); + +int pciehp_slot_reset(struct pcie_device *dev); + +static inline const char *slot_name(struct controller *ctrl) +{ + return hotplug_slot_name(&ctrl->hotplug_slot); +} + +static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot) +{ + return container_of(hotplug_slot, struct controller, hotplug_slot); +} + +#endif /* _PCIEHP_H */ |