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/sched/signal.h> /* signal_pending() */ 23 #include <linux/mutex.h> 24 #include <linux/rwsem.h> 25 #include <linux/workqueue.h> 26 27 #include "../pcie/portdrv.h" 28 29 #define MY_NAME "pciehp" 30 31 extern bool pciehp_poll_mode; 32 extern int pciehp_poll_time; 33 extern bool pciehp_debug; 34 35 #define dbg(format, arg...) \ 36 do { \ 37 if (pciehp_debug) \ 38 printk(KERN_DEBUG "%s: " format, MY_NAME, ## arg); \ 39 } while (0) 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) 46 47 #define ctrl_dbg(ctrl, format, arg...) \ 48 do { \ 49 if (pciehp_debug) \ 50 dev_printk(KERN_DEBUG, &ctrl->pcie->device, \ 51 format, ## arg); \ 52 } while (0) 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) 59 60 #define SLOT_NAME_SIZE 10 61 62 /** 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 71 */ 72 struct slot { 73 u8 state; 74 struct controller *ctrl; 75 struct hotplug_slot *hotplug_slot; 76 struct delayed_work work; 77 struct mutex lock; 78 }; 79 80 /** 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 * @slot: pointer to the controller's slot structure 88 * @queue: wait queue to wake up on reception of a Command Completed event, 89 * used for synchronous writes to the Slot Control register 90 * @slot_cap: cached copy of the Slot Capabilities register 91 * @slot_ctrl: cached copy of the Slot Control register 92 * @poll_thread: thread to poll for slot events if no IRQ is available, 93 * enabled with pciehp_poll_mode module parameter 94 * @cmd_started: jiffies when the Slot Control register was last written; 95 * the next write is allowed 1 second later, absent a Command Completed 96 * interrupt (PCIe r4.0, sec 6.7.3.2) 97 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler 98 * on reception of a Command Completed event 99 * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting 100 * Capable bit in Link Capabilities register; if this bit is zero, the 101 * Data Link Layer Link Active bit in the Link Status register will never 102 * be set and the driver is thus confined to wait 1 second before assuming 103 * the link to a hotplugged device is up and accessing it 104 * @notification_enabled: whether the IRQ was requested successfully 105 * @power_fault_detected: whether a power fault was detected by the hardware 106 * that has not yet been cleared by the user 107 * @pending_events: used by the IRQ handler to save events retrieved from the 108 * Slot Status register for later consumption by the IRQ thread 109 * @request_result: result of last user request submitted to the IRQ thread 110 * @requester: wait queue to wake up on completion of user request, 111 * used for synchronous slot enable/disable request via sysfs 112 */ 113 struct controller { 114 struct mutex ctrl_lock; 115 struct pcie_device *pcie; 116 struct rw_semaphore reset_lock; 117 struct slot *slot; 118 wait_queue_head_t queue; 119 u32 slot_cap; 120 u16 slot_ctrl; 121 struct task_struct *poll_thread; 122 unsigned long cmd_started; /* jiffies */ 123 unsigned int cmd_busy:1; 124 unsigned int link_active_reporting:1; 125 unsigned int notification_enabled:1; 126 unsigned int power_fault_detected; 127 atomic_t pending_events; 128 int request_result; 129 wait_queue_head_t requester; 130 }; 131 132 /** 133 * DOC: Slot state 134 * 135 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated 136 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay, 137 * green led is blinking 138 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay, 139 * green led is blinking 140 * @POWERON_STATE: slot is currently powering on 141 * @POWEROFF_STATE: slot is currently powering off 142 * @ON_STATE: slot is powered on, subordinate devices have been enumerated 143 */ 144 #define OFF_STATE 0 145 #define BLINKINGON_STATE 1 146 #define BLINKINGOFF_STATE 2 147 #define POWERON_STATE 3 148 #define POWEROFF_STATE 4 149 #define ON_STATE 5 150 151 /** 152 * DOC: Flags to request an action from the IRQ thread 153 * 154 * These are stored together with events read from the Slot Status register, 155 * hence must be greater than its 16-bit width. 156 * 157 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or 158 * an Attention Button press after the 5 second delay 159 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the 160 * hotplug port was inaccessible when the interrupt occurred, requiring 161 * that the IRQ handler is rerun by the IRQ thread after it has made the 162 * hotplug port accessible by runtime resuming its parents to D0 163 */ 164 #define DISABLE_SLOT (1 << 16) 165 #define RERUN_ISR (1 << 17) 166 167 #define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP) 168 #define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP) 169 #define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP) 170 #define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP) 171 #define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP) 172 #define HP_SUPR_RM(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_HPS) 173 #define EMI(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_EIP) 174 #define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS) 175 #define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19) 176 177 int pciehp_sysfs_enable_slot(struct slot *slot); 178 int pciehp_sysfs_disable_slot(struct slot *slot); 179 void pciehp_request(struct controller *ctrl, int action); 180 void pciehp_handle_button_press(struct slot *slot); 181 void pciehp_handle_disable_request(struct slot *slot); 182 void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events); 183 int pciehp_configure_device(struct slot *p_slot); 184 void pciehp_unconfigure_device(struct slot *p_slot); 185 void pciehp_queue_pushbutton_work(struct work_struct *work); 186 struct controller *pcie_init(struct pcie_device *dev); 187 int pcie_init_notification(struct controller *ctrl); 188 void pcie_shutdown_notification(struct controller *ctrl); 189 void pcie_clear_hotplug_events(struct controller *ctrl); 190 int pciehp_power_on_slot(struct slot *slot); 191 void pciehp_power_off_slot(struct slot *slot); 192 void pciehp_get_power_status(struct slot *slot, u8 *status); 193 void pciehp_get_attention_status(struct slot *slot, u8 *status); 194 195 void pciehp_set_attention_status(struct slot *slot, u8 status); 196 void pciehp_get_latch_status(struct slot *slot, u8 *status); 197 void pciehp_get_adapter_status(struct slot *slot, u8 *status); 198 int pciehp_query_power_fault(struct slot *slot); 199 void pciehp_green_led_on(struct slot *slot); 200 void pciehp_green_led_off(struct slot *slot); 201 void pciehp_green_led_blink(struct slot *slot); 202 int pciehp_check_link_status(struct controller *ctrl); 203 bool pciehp_check_link_active(struct controller *ctrl); 204 void pciehp_release_ctrl(struct controller *ctrl); 205 int pciehp_reset_slot(struct slot *slot, int probe); 206 207 int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status); 208 int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status); 209 210 static inline const char *slot_name(struct slot *slot) 211 { 212 return hotplug_slot_name(slot->hotplug_slot); 213 } 214 215 #endif /* _PCIEHP_H */ 216