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
28 extern bool pciehp_poll_mode;
29 extern 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 * @inband_presence_disabled: In-Band Presence Detect Disable supported by
51 * controller and disabled per spec recommendation (PCIe r5.0, appendix I
52 * implementation note)
53 * @slot_ctrl: cached copy of the Slot Control register
54 * @ctrl_lock: serializes writes to the Slot Control register
55 * @cmd_started: jiffies when the Slot Control register was last written;
56 * the next write is allowed 1 second later, absent a Command Completed
57 * interrupt (PCIe r4.0, sec 6.7.3.2)
58 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
59 * on reception of a Command Completed event
60 * @queue: wait queue to wake up on reception of a Command Completed event,
61 * used for synchronous writes to the Slot Control register
62 * @pending_events: used by the IRQ handler to save events retrieved from the
63 * Slot Status register for later consumption by the IRQ thread
64 * @notification_enabled: whether the IRQ was requested successfully
65 * @power_fault_detected: whether a power fault was detected by the hardware
66 * that has not yet been cleared by the user
67 * @poll_thread: thread to poll for slot events if no IRQ is available,
68 * enabled with pciehp_poll_mode module parameter
69 * @state: current state machine position
70 * @state_lock: protects reads and writes of @state;
71 * protects scheduling, execution and cancellation of @button_work
72 * @button_work: work item to turn the slot on or off after 5 seconds
73 * in response to an Attention Button press
74 * @hotplug_slot: structure registered with the PCI hotplug core
75 * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
76 * Link Status register and to the Presence Detect State bit in the Slot
77 * Status register during a slot reset which may cause them to flap
78 * @depth: Number of additional hotplug ports in the path to the root bus,
79 * used as lock subclass for @reset_lock
80 * @ist_running: flag to keep user request waiting while IRQ thread is running
81 * @request_result: result of last user request submitted to the IRQ thread
82 * @requester: wait queue to wake up on completion of user request,
83 * used for synchronous slot enable/disable request via sysfs
84 *
85 * PCIe hotplug has a 1:1 relationship between controller and slot, hence
86 * unlike other drivers, the two aren't represented by separate structures.
87 */
88 struct controller {
89 struct pcie_device *pcie;
90
91 u32 slot_cap; /* capabilities and quirks */
92 unsigned int inband_presence_disabled:1;
93
94 u16 slot_ctrl; /* control register access */
95 struct mutex ctrl_lock;
96 unsigned long cmd_started;
97 unsigned int cmd_busy:1;
98 wait_queue_head_t queue;
99
100 atomic_t pending_events; /* event handling */
101 unsigned int notification_enabled:1;
102 unsigned int power_fault_detected;
103 struct task_struct *poll_thread;
104
105 u8 state; /* state machine */
106 struct mutex state_lock;
107 struct delayed_work button_work;
108
109 struct hotplug_slot hotplug_slot; /* hotplug core interface */
110 struct rw_semaphore reset_lock;
111 unsigned int depth;
112 unsigned int ist_running;
113 int request_result;
114 wait_queue_head_t requester;
115 };
116
117 /**
118 * DOC: Slot state
119 *
120 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
121 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
122 * Power Indicator is blinking
123 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
124 * Power Indicator is blinking
125 * @POWERON_STATE: slot is currently powering on
126 * @POWEROFF_STATE: slot is currently powering off
127 * @ON_STATE: slot is powered on, subordinate devices have been enumerated
128 */
129 #define OFF_STATE 0
130 #define BLINKINGON_STATE 1
131 #define BLINKINGOFF_STATE 2
132 #define POWERON_STATE 3
133 #define POWEROFF_STATE 4
134 #define ON_STATE 5
135
136 /**
137 * DOC: Flags to request an action from the IRQ thread
138 *
139 * These are stored together with events read from the Slot Status register,
140 * hence must be greater than its 16-bit width.
141 *
142 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
143 * an Attention Button press after the 5 second delay
144 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
145 * hotplug port was inaccessible when the interrupt occurred, requiring
146 * that the IRQ handler is rerun by the IRQ thread after it has made the
147 * hotplug port accessible by runtime resuming its parents to D0
148 */
149 #define DISABLE_SLOT (1 << 16)
150 #define RERUN_ISR (1 << 17)
151
152 #define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
153 #define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
154 #define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
155 #define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
156 #define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
157 #define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
158 #define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
159
160 void pciehp_request(struct controller *ctrl, int action);
161 void pciehp_handle_button_press(struct controller *ctrl);
162 void pciehp_handle_disable_request(struct controller *ctrl);
163 void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
164 int pciehp_configure_device(struct controller *ctrl);
165 void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
166 void pciehp_queue_pushbutton_work(struct work_struct *work);
167 struct controller *pcie_init(struct pcie_device *dev);
168 int pcie_init_notification(struct controller *ctrl);
169 void pcie_shutdown_notification(struct controller *ctrl);
170 void pcie_clear_hotplug_events(struct controller *ctrl);
171 void pcie_enable_interrupt(struct controller *ctrl);
172 void pcie_disable_interrupt(struct controller *ctrl);
173 int pciehp_power_on_slot(struct controller *ctrl);
174 void pciehp_power_off_slot(struct controller *ctrl);
175 void pciehp_get_power_status(struct controller *ctrl, u8 *status);
176
177 #define INDICATOR_NOOP -1 /* Leave indicator unchanged */
178 void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);
179
180 void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
181 int pciehp_query_power_fault(struct controller *ctrl);
182 int pciehp_card_present(struct controller *ctrl);
183 int pciehp_card_present_or_link_active(struct controller *ctrl);
184 int pciehp_check_link_status(struct controller *ctrl);
185 int pciehp_check_link_active(struct controller *ctrl);
186 void pciehp_release_ctrl(struct controller *ctrl);
187
188 int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
189 int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
190 int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe);
191 int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
192 int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
193 int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
194
195 int pciehp_slot_reset(struct pcie_device *dev);
196
slot_name(struct controller * ctrl)197 static inline const char *slot_name(struct controller *ctrl)
198 {
199 return hotplug_slot_name(&ctrl->hotplug_slot);
200 }
201
to_ctrl(struct hotplug_slot * hotplug_slot)202 static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot)
203 {
204 return container_of(hotplug_slot, struct controller, hotplug_slot);
205 }
206
207 #endif /* _PCIEHP_H */
208