include/linux/arm_sdei.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2017 Arm Ltd.
   3 #ifndef __LINUX_ARM_SDEI_H
   4 #define __LINUX_ARM_SDEI_H
   5
   6 #include <uapi/linux/arm_sdei.h>
   7
   8 #include <acpi/ghes.h>
   9
  10 #ifdef CONFIG_ARM_SDE_INTERFACE
  11 #include <asm/sdei.h>
  12 #endif
  13
  14 /* Arch code should override this to set the entry point from firmware... */
  15 #ifndef sdei_arch_get_entry_point
  16 #define sdei_arch_get_entry_point(conduit)      (0)
  17 #endif
  18
  19 /*
  20  * When an event occurs sdei_event_handler() will call a user-provided callback
  21  * like this in NMI context on the CPU that received the event.
  22  */
  23 typedef int (sdei_event_callback)(u32 event, struct pt_regs *regs, void *arg);
  24
  25 /*
  26  * Register your callback to claim an event. The event must be described
  27  * by firmware.
  28  */
  29 int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg);
  30
  31 /*
  32  * Calls to sdei_event_unregister() may return EINPROGRESS. Keep calling
  33  * it until it succeeds.
  34  */
  35 int sdei_event_unregister(u32 event_num);
  36
  37 int sdei_event_enable(u32 event_num);
  38 int sdei_event_disable(u32 event_num);
  39
  40 /* GHES register/unregister helpers */
  41 int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb,
  42                        sdei_event_callback *critical_cb);
  43 int sdei_unregister_ghes(struct ghes *ghes);
  44
  45 #ifdef CONFIG_ARM_SDE_INTERFACE
  46 /* For use by arch code when CPU hotplug notifiers are not appropriate. */
  47 int sdei_mask_local_cpu(void);
  48 int sdei_unmask_local_cpu(void);
  49 void __init sdei_init(void);
  50 void sdei_handler_abort(void);
  51 #else
  52 static inline int sdei_mask_local_cpu(void) { return 0; }
  53 static inline int sdei_unmask_local_cpu(void) { return 0; }
  54 static inline void sdei_init(void) { }
  55 static inline void sdei_handler_abort(void) { }
  56 #endif /* CONFIG_ARM_SDE_INTERFACE */
  57
  58
  59 /*
  60  * This struct represents an event that has been registered. The driver
  61  * maintains a list of all events, and which ones are registered. (Private
  62  * events have one entry in the list, but are registered on each CPU).
  63  * A pointer to this struct is passed to firmware, and back to the event
  64  * handler. The event handler can then use this to invoke the registered
  65  * callback, without having to walk the list.
  66  *
  67  * For CPU private events, this structure is per-cpu.
  68  */
  69 struct sdei_registered_event {
  70         /* For use by arch code: */
  71         struct pt_regs          interrupted_regs;
  72
  73         sdei_event_callback     *callback;
  74         void                    *callback_arg;
  75         u32                      event_num;
  76         u8                       priority;
  77 };
  78
  79 /* The arch code entry point should then call this when an event arrives. */
  80 int notrace sdei_event_handler(struct pt_regs *regs,
  81                                struct sdei_registered_event *arg);
  82
  83 /* arch code may use this to retrieve the extra registers. */
  84 int sdei_api_event_context(u32 query, u64 *result);
  85
  86 #endif /* __LINUX_ARM_SDEI_H */