tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * PCI Express Hot Plug Controller Driver
4 *
5 * Copyright (C) 1995,2001 Compaq Computer Corporation
6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
7 * Copyright (C) 2001 IBM Corp.
8 * Copyright (C) 2003-2004 Intel Corporation
9 *
10 * All rights reserved.
11 *
12 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
13 *
14 */
15#ifndef _PCIEHP_H
16#define _PCIEHP_H
17
18#include <linux/types.h>
19#include <linux/pci.h>
20#include <linux/pci_hotplug.h>
21#include <linux/delay.h>
22#include <linux/mutex.h>
23#include <linux/rwsem.h>
24#include <linux/workqueue.h>
25
26#include "../pcie/portdrv.h"
27
28extern bool pciehp_poll_mode;
29extern int pciehp_poll_time;
30
31/*
32 * Set CONFIG_DYNAMIC_DEBUG=y and boot with 'dyndbg="file pciehp* +p"' to
33 * enable debug messages.
34 */
35#define ctrl_dbg(ctrl, format, arg...) \
36 pci_dbg(ctrl->pcie->port, format, ## arg)
37#define ctrl_err(ctrl, format, arg...) \
38 pci_err(ctrl->pcie->port, format, ## arg)
39#define ctrl_info(ctrl, format, arg...) \
40 pci_info(ctrl->pcie->port, format, ## arg)
41#define ctrl_warn(ctrl, format, arg...) \
42 pci_warn(ctrl->pcie->port, format, ## arg)
43
44#define SLOT_NAME_SIZE 10
45
46/**
47 * struct controller - PCIe hotplug controller
48 * @pcie: pointer to the controller's PCIe port service device
49 * @slot_cap: cached copy of the Slot Capabilities register
50 * @slot_ctrl: cached copy of the Slot Control register
51 * @ctrl_lock: serializes writes to the Slot Control register
52 * @cmd_started: jiffies when the Slot Control register was last written;
53 * the next write is allowed 1 second later, absent a Command Completed
54 * interrupt (PCIe r4.0, sec 6.7.3.2)
55 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
56 * on reception of a Command Completed event
57 * @queue: wait queue to wake up on reception of a Command Completed event,
58 * used for synchronous writes to the Slot Control register
59 * @pending_events: used by the IRQ handler to save events retrieved from the
60 * Slot Status register for later consumption by the IRQ thread
61 * @notification_enabled: whether the IRQ was requested successfully
62 * @power_fault_detected: whether a power fault was detected by the hardware
63 * that has not yet been cleared by the user
64 * @poll_thread: thread to poll for slot events if no IRQ is available,
65 * enabled with pciehp_poll_mode module parameter
66 * @state: current state machine position
67 * @state_lock: protects reads and writes of @state;
68 * protects scheduling, execution and cancellation of @button_work
69 * @button_work: work item to turn the slot on or off after 5 seconds
70 * in response to an Attention Button press
71 * @hotplug_slot: structure registered with the PCI hotplug core
72 * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
73 * Link Status register and to the Presence Detect State bit in the Slot
74 * Status register during a slot reset which may cause them to flap
75 * @ist_running: flag to keep user request waiting while IRQ thread is running
76 * @request_result: result of last user request submitted to the IRQ thread
77 * @requester: wait queue to wake up on completion of user request,
78 * used for synchronous slot enable/disable request via sysfs
79 *
80 * PCIe hotplug has a 1:1 relationship between controller and slot, hence
81 * unlike other drivers, the two aren't represented by separate structures.
82 */
83struct controller {
84 struct pcie_device *pcie;
85
86 u32 slot_cap; /* capabilities and quirks */
87
88 u16 slot_ctrl; /* control register access */
89 struct mutex ctrl_lock;
90 unsigned long cmd_started;
91 unsigned int cmd_busy:1;
92 wait_queue_head_t queue;
93
94 atomic_t pending_events; /* event handling */
95 unsigned int notification_enabled:1;
96 unsigned int power_fault_detected;
97 struct task_struct *poll_thread;
98
99 u8 state; /* state machine */
100 struct mutex state_lock;
101 struct delayed_work button_work;
102
103 struct hotplug_slot hotplug_slot; /* hotplug core interface */
104 struct rw_semaphore reset_lock;
105 unsigned int ist_running;
106 int request_result;
107 wait_queue_head_t requester;
108};
109
110/**
111 * DOC: Slot state
112 *
113 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
114 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
115 * Power Indicator is blinking
116 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
117 * Power Indicator is blinking
118 * @POWERON_STATE: slot is currently powering on
119 * @POWEROFF_STATE: slot is currently powering off
120 * @ON_STATE: slot is powered on, subordinate devices have been enumerated
121 */
122#define OFF_STATE 0
123#define BLINKINGON_STATE 1
124#define BLINKINGOFF_STATE 2
125#define POWERON_STATE 3
126#define POWEROFF_STATE 4
127#define ON_STATE 5
128
129/**
130 * DOC: Flags to request an action from the IRQ thread
131 *
132 * These are stored together with events read from the Slot Status register,
133 * hence must be greater than its 16-bit width.
134 *
135 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
136 * an Attention Button press after the 5 second delay
137 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
138 * hotplug port was inaccessible when the interrupt occurred, requiring
139 * that the IRQ handler is rerun by the IRQ thread after it has made the
140 * hotplug port accessible by runtime resuming its parents to D0
141 */
142#define DISABLE_SLOT (1 << 16)
143#define RERUN_ISR (1 << 17)
144
145#define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
146#define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
147#define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
148#define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
149#define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
150#define HP_SUPR_RM(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_HPS)
151#define EMI(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_EIP)
152#define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
153#define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
154
155void pciehp_request(struct controller *ctrl, int action);
156void pciehp_handle_button_press(struct controller *ctrl);
157void pciehp_handle_disable_request(struct controller *ctrl);
158void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
159int pciehp_configure_device(struct controller *ctrl);
160void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
161void pciehp_queue_pushbutton_work(struct work_struct *work);
162struct controller *pcie_init(struct pcie_device *dev);
163int pcie_init_notification(struct controller *ctrl);
164void pcie_shutdown_notification(struct controller *ctrl);
165void pcie_clear_hotplug_events(struct controller *ctrl);
166void pcie_enable_interrupt(struct controller *ctrl);
167void pcie_disable_interrupt(struct controller *ctrl);
168int pciehp_power_on_slot(struct controller *ctrl);
169void pciehp_power_off_slot(struct controller *ctrl);
170void pciehp_get_power_status(struct controller *ctrl, u8 *status);
171
172#define INDICATOR_NOOP -1 /* Leave indicator unchanged */
173void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);
174
175void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
176int pciehp_query_power_fault(struct controller *ctrl);
177int pciehp_card_present(struct controller *ctrl);
178int pciehp_card_present_or_link_active(struct controller *ctrl);
179int pciehp_check_link_status(struct controller *ctrl);
180int pciehp_check_link_active(struct controller *ctrl);
181void pciehp_release_ctrl(struct controller *ctrl);
182
183int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
184int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
185int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe);
186int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
187int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
188int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
189
190static inline const char *slot_name(struct controller *ctrl)
191{
192 return hotplug_slot_name(&ctrl->hotplug_slot);
193}
194
195static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot)
196{
197 return container_of(hotplug_slot, struct controller, hotplug_slot);
198}
199
200#endif /* _PCIEHP_H */