1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * PCI Express Hot Plug Controller Driver
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
10 * All rights reserved.
12 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
18 #include <linux/types.h>
19 #include <linux/pci.h>
20 #include <linux/pci_hotplug.h>
21 #include <linux/delay.h>
22 #include <linux/sched/signal.h> /* signal_pending() */
23 #include <linux/mutex.h>
24 #include <linux/rwsem.h>
25 #include <linux/workqueue.h>
27 #include "../pcie/portdrv.h"
29 #define MY_NAME "pciehp"
31 extern bool pciehp_poll_mode;
32 extern int pciehp_poll_time;
33 extern bool pciehp_debug;
35 #define dbg(format, arg...) \
38 printk(KERN_DEBUG "%s: " format, MY_NAME, ## arg); \
40 #define err(format, arg...) \
41 printk(KERN_ERR "%s: " format, MY_NAME, ## arg)
42 #define info(format, arg...) \
43 printk(KERN_INFO "%s: " format, MY_NAME, ## arg)
44 #define warn(format, arg...) \
45 printk(KERN_WARNING "%s: " format, MY_NAME, ## arg)
47 #define ctrl_dbg(ctrl, format, arg...) \
50 dev_printk(KERN_DEBUG, &ctrl->pcie->device, \
53 #define ctrl_err(ctrl, format, arg...) \
54 dev_err(&ctrl->pcie->device, format, ## arg)
55 #define ctrl_info(ctrl, format, arg...) \
56 dev_info(&ctrl->pcie->device, format, ## arg)
57 #define ctrl_warn(ctrl, format, arg...) \
58 dev_warn(&ctrl->pcie->device, format, ## arg)
60 #define SLOT_NAME_SIZE 10
63 * struct slot - PCIe hotplug slot
64 * @state: current state machine position
65 * @ctrl: pointer to the slot's controller structure
66 * @hotplug_slot: pointer to the structure registered with the PCI hotplug core
67 * @work: work item to turn the slot on or off after 5 seconds in response to
68 * an Attention Button press
69 * @lock: protects reads and writes of @state;
70 * protects scheduling, execution and cancellation of @work
74 struct controller *ctrl;
75 struct hotplug_slot *hotplug_slot;
76 struct delayed_work work;
81 * struct controller - PCIe hotplug controller
82 * @ctrl_lock: serializes writes to the Slot Control register
83 * @pcie: pointer to the controller's PCIe port service device
84 * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
85 * Link Status register and to the Presence Detect State bit in the Slot
86 * Status register during a slot reset which may cause them to flap
87 * @depth: Number of additional hotplug ports in the path to the root bus,
88 * used as lock subclass for @reset_lock
89 * @slot: pointer to the controller's slot structure
90 * @queue: wait queue to wake up on reception of a Command Completed event,
91 * used for synchronous writes to the Slot Control register
92 * @slot_cap: cached copy of the Slot Capabilities register
93 * @slot_ctrl: cached copy of the Slot Control register
94 * @poll_thread: thread to poll for slot events if no IRQ is available,
95 * enabled with pciehp_poll_mode module parameter
96 * @cmd_started: jiffies when the Slot Control register was last written;
97 * the next write is allowed 1 second later, absent a Command Completed
98 * interrupt (PCIe r4.0, sec 6.7.3.2)
99 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
100 * on reception of a Command Completed event
101 * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
102 * Capable bit in Link Capabilities register; if this bit is zero, the
103 * Data Link Layer Link Active bit in the Link Status register will never
104 * be set and the driver is thus confined to wait 1 second before assuming
105 * the link to a hotplugged device is up and accessing it
106 * @notification_enabled: whether the IRQ was requested successfully
107 * @power_fault_detected: whether a power fault was detected by the hardware
108 * that has not yet been cleared by the user
109 * @pending_events: used by the IRQ handler to save events retrieved from the
110 * Slot Status register for later consumption by the IRQ thread
111 * @ist_running: flag to keep user request waiting while IRQ thread is running
112 * @request_result: result of last user request submitted to the IRQ thread
113 * @requester: wait queue to wake up on completion of user request,
114 * used for synchronous slot enable/disable request via sysfs
117 struct mutex ctrl_lock;
118 struct pcie_device *pcie;
119 struct rw_semaphore reset_lock;
122 wait_queue_head_t queue;
125 struct task_struct *poll_thread;
126 unsigned long cmd_started; /* jiffies */
127 unsigned int cmd_busy:1;
128 unsigned int link_active_reporting:1;
129 unsigned int notification_enabled:1;
130 unsigned int power_fault_detected;
131 atomic_t pending_events;
132 unsigned int ist_running;
134 wait_queue_head_t requester;
140 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
141 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
142 * green led is blinking
143 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
144 * green led is blinking
145 * @POWERON_STATE: slot is currently powering on
146 * @POWEROFF_STATE: slot is currently powering off
147 * @ON_STATE: slot is powered on, subordinate devices have been enumerated
150 #define BLINKINGON_STATE 1
151 #define BLINKINGOFF_STATE 2
152 #define POWERON_STATE 3
153 #define POWEROFF_STATE 4
157 * DOC: Flags to request an action from the IRQ thread
159 * These are stored together with events read from the Slot Status register,
160 * hence must be greater than its 16-bit width.
162 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
163 * an Attention Button press after the 5 second delay
164 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
165 * hotplug port was inaccessible when the interrupt occurred, requiring
166 * that the IRQ handler is rerun by the IRQ thread after it has made the
167 * hotplug port accessible by runtime resuming its parents to D0
169 #define DISABLE_SLOT (1 << 16)
170 #define RERUN_ISR (1 << 17)
172 #define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
173 #define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
174 #define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
175 #define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
176 #define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
177 #define HP_SUPR_RM(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_HPS)
178 #define EMI(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_EIP)
179 #define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
180 #define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
182 int pciehp_sysfs_enable_slot(struct slot *slot);
183 int pciehp_sysfs_disable_slot(struct slot *slot);
184 void pciehp_request(struct controller *ctrl, int action);
185 void pciehp_handle_button_press(struct slot *slot);
186 void pciehp_handle_disable_request(struct slot *slot);
187 void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events);
188 int pciehp_configure_device(struct slot *p_slot);
189 void pciehp_unconfigure_device(struct slot *p_slot);
190 void pciehp_queue_pushbutton_work(struct work_struct *work);
191 struct controller *pcie_init(struct pcie_device *dev);
192 int pcie_init_notification(struct controller *ctrl);
193 void pcie_shutdown_notification(struct controller *ctrl);
194 void pcie_clear_hotplug_events(struct controller *ctrl);
195 int pciehp_power_on_slot(struct slot *slot);
196 void pciehp_power_off_slot(struct slot *slot);
197 void pciehp_get_power_status(struct slot *slot, u8 *status);
198 void pciehp_get_attention_status(struct slot *slot, u8 *status);
200 void pciehp_set_attention_status(struct slot *slot, u8 status);
201 void pciehp_get_latch_status(struct slot *slot, u8 *status);
202 void pciehp_get_adapter_status(struct slot *slot, u8 *status);
203 int pciehp_query_power_fault(struct slot *slot);
204 void pciehp_green_led_on(struct slot *slot);
205 void pciehp_green_led_off(struct slot *slot);
206 void pciehp_green_led_blink(struct slot *slot);
207 int pciehp_check_link_status(struct controller *ctrl);
208 bool pciehp_check_link_active(struct controller *ctrl);
209 void pciehp_release_ctrl(struct controller *ctrl);
210 int pciehp_reset_slot(struct slot *slot, int probe);
212 int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
213 int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
215 static inline const char *slot_name(struct slot *slot)
217 return hotplug_slot_name(slot->hotplug_slot);
220 #endif /* _PCIEHP_H */