1 /* 2 * Copyright 2016 Intel Corp. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 21 * OTHER DEALINGS IN THE SOFTWARE. 22 */ 23 24 #ifndef _DRM_VBLANK_H_ 25 #define _DRM_VBLANK_H_ 26 27 #include <linux/seqlock.h> 28 #include <linux/idr.h> 29 #include <linux/poll.h> 30 31 #include <drm/drm_file.h> 32 #include <drm/drm_modes.h> 33 #include <uapi/drm/drm.h> 34 35 struct drm_device; 36 struct drm_crtc; 37 38 /** 39 * struct drm_pending_vblank_event - pending vblank event tracking 40 */ 41 struct drm_pending_vblank_event { 42 /** 43 * @base: Base structure for tracking pending DRM events. 44 */ 45 struct drm_pending_event base; 46 /** 47 * @pipe: drm_crtc_index() of the &drm_crtc this event is for. 48 */ 49 unsigned int pipe; 50 /** 51 * @event: Actual event which will be sent to userspace. 52 */ 53 struct drm_event_vblank event; 54 }; 55 56 /** 57 * struct drm_vblank_crtc - vblank tracking for a CRTC 58 * 59 * This structure tracks the vblank state for one CRTC. 60 * 61 * Note that for historical reasons - the vblank handling code is still shared 62 * with legacy/non-kms drivers - this is a free-standing structure not directly 63 * connected to &struct drm_crtc. But all public interface functions are taking 64 * a &struct drm_crtc to hide this implementation detail. 65 */ 66 struct drm_vblank_crtc { 67 /** 68 * @dev: Pointer to the &drm_device. 69 */ 70 struct drm_device *dev; 71 /** 72 * @queue: Wait queue for vblank waiters. 73 */ 74 wait_queue_head_t queue; /**< VBLANK wait queue */ 75 /** 76 * @disable_timer: Disable timer for the delayed vblank disabling 77 * hysteresis logic. Vblank disabling is controlled through the 78 * drm_vblank_offdelay module option and the setting of the 79 * &drm_device.max_vblank_count value. 80 */ 81 struct timer_list disable_timer; 82 83 /** 84 * @seqlock: Protect vblank count and time. 85 */ 86 seqlock_t seqlock; /* protects vblank count and time */ 87 88 /** 89 * @count: Current software vblank counter. 90 */ 91 u32 count; 92 /** 93 * @time: Vblank timestamp corresponding to @count. 94 */ 95 struct timeval time; 96 97 /** 98 * @refcount: Number of users/waiters of the vblank interrupt. Only when 99 * this refcount reaches 0 can the hardware interrupt be disabled using 100 * @disable_timer. 101 */ 102 atomic_t refcount; /* number of users of vblank interruptsper crtc */ 103 /** 104 * @last: Protected by &drm_device.vbl_lock, used for wraparound handling. 105 */ 106 u32 last; 107 /** 108 * @inmodeset: Tracks whether the vblank is disabled due to a modeset. 109 * For legacy driver bit 2 additionally tracks whether an additional 110 * temporary vblank reference has been acquired to paper over the 111 * hardware counter resetting/jumping. KMS drivers should instead just 112 * call drm_crtc_vblank_off() and drm_crtc_vblank_on(), which explicitly 113 * save and restore the vblank count. 114 */ 115 unsigned int inmodeset; /* Display driver is setting mode */ 116 /** 117 * @pipe: drm_crtc_index() of the &drm_crtc corresponding to this 118 * structure. 119 */ 120 unsigned int pipe; 121 /** 122 * @framedur_ns: Frame/Field duration in ns, used by 123 * drm_calc_vbltimestamp_from_scanoutpos() and computed by 124 * drm_calc_timestamping_constants(). 125 */ 126 int framedur_ns; 127 /** 128 * @linedur_ns: Line duration in ns, used by 129 * drm_calc_vbltimestamp_from_scanoutpos() and computed by 130 * drm_calc_timestamping_constants(). 131 */ 132 int linedur_ns; 133 134 /** 135 * @hwmode: 136 * 137 * Cache of the current hardware display mode. Only valid when @enabled 138 * is set. This is used by helpers like 139 * drm_calc_vbltimestamp_from_scanoutpos(). We can't just access the 140 * hardware mode by e.g. looking at &drm_crtc_state.adjusted_mode, 141 * because that one is really hard to get from interrupt context. 142 */ 143 struct drm_display_mode hwmode; 144 145 /** 146 * @enabled: Tracks the enabling state of the corresponding &drm_crtc to 147 * avoid double-disabling and hence corrupting saved state. Needed by 148 * drivers not using atomic KMS, since those might go through their CRTC 149 * disabling functions multiple times. 150 */ 151 bool enabled; 152 }; 153 154 int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs); 155 u32 drm_crtc_vblank_count(struct drm_crtc *crtc); 156 u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, 157 struct timeval *vblanktime); 158 void drm_crtc_send_vblank_event(struct drm_crtc *crtc, 159 struct drm_pending_vblank_event *e); 160 void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, 161 struct drm_pending_vblank_event *e); 162 bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe); 163 bool drm_crtc_handle_vblank(struct drm_crtc *crtc); 164 int drm_crtc_vblank_get(struct drm_crtc *crtc); 165 void drm_crtc_vblank_put(struct drm_crtc *crtc); 166 void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe); 167 void drm_crtc_wait_one_vblank(struct drm_crtc *crtc); 168 void drm_crtc_vblank_off(struct drm_crtc *crtc); 169 void drm_crtc_vblank_reset(struct drm_crtc *crtc); 170 void drm_crtc_vblank_on(struct drm_crtc *crtc); 171 void drm_vblank_cleanup(struct drm_device *dev); 172 u32 drm_accurate_vblank_count(struct drm_crtc *crtc); 173 174 bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, 175 unsigned int pipe, int *max_error, 176 struct timeval *vblank_time, 177 bool in_vblank_irq); 178 void drm_calc_timestamping_constants(struct drm_crtc *crtc, 179 const struct drm_display_mode *mode); 180 wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc); 181 #endif 182