Orange Pi5 kernel

/*
 * drm_irq.c IRQ and vblank support
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */
 
#include <linux/export.h>
#include <linux/kthread.h>
#include <linux/moduleparam.h>
 
#include <drm/drm_crtc.h>
#include <drm/drm_drv.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_vblank.h>
 
#include "drm_internal.h"
#include "drm_trace.h"
 
/**
 * DOC: vblank handling
 *
 * From the computer's perspective, every time the monitor displays
 * a new frame the scanout engine has "scanned out" the display image
 * from top to bottom, one row of pixels at a time. The current row
 * of pixels is referred to as the current scanline.
 *
 * In addition to the display's visible area, there's usually a couple of
 * extra scanlines which aren't actually displayed on the screen.
 * These extra scanlines don't contain image data and are occasionally used
 * for features like audio and infoframes. The region made up of these
 * scanlines is referred to as the vertical blanking region, or vblank for
 * short.
 *
 * For historical reference, the vertical blanking period was designed to
 * give the electron gun (on CRTs) enough time to move back to the top of
 * the screen to start scanning out the next frame. Similar for horizontal
 * blanking periods. They were designed to give the electron gun enough
 * time to move back to the other side of the screen to start scanning the
 * next scanline.
 *
 * ::
 *
 *
 *    physical →   ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽
 *    top of      |                                        |
 *    display     |                                        |
 *                |               New frame                |
 *                |                                        |
 *                |↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓|
 *                |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| ← Scanline,
 *                |↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓|   updates the
 *                |                                        |   frame as it
 *                |                                        |   travels down
 *                |                                        |   ("sacn out")
 *                |               Old frame                |
 *                |                                        |
 *                |                                        |
 *                |                                        |
 *                |                                        |   physical
 *                |                                        |   bottom of
 *    vertical    |⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽| ← display
 *    blanking    ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆
 *    region   →  ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆
 *                ┆xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx┆
 *    start of →   ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽
 *    new frame
 *
 * "Physical top of display" is the reference point for the high-precision/
 * corrected timestamp.
 *
 * On a lot of display hardware, programming needs to take effect during the
 * vertical blanking period so that settings like gamma, the image buffer
 * buffer to be scanned out, etc. can safely be changed without showing
 * any visual artifacts on the screen. In some unforgiving hardware, some of
 * this programming has to both start and end in the same vblank. To help
 * with the timing of the hardware programming, an interrupt is usually
 * available to notify the driver when it can start the updating of registers.
 * The interrupt is in this context named the vblank interrupt.
 *
 * The vblank interrupt may be fired at different points depending on the
 * hardware. Some hardware implementations will fire the interrupt when the
 * new frame start, other implementations will fire the interrupt at different
 * points in time.
 *
 * Vertical blanking plays a major role in graphics rendering. To achieve
 * tear-free display, users must synchronize page flips and/or rendering to
 * vertical blanking. The DRM API offers ioctls to perform page flips
 * synchronized to vertical blanking and wait for vertical blanking.
 *
 * The DRM core handles most of the vertical blanking management logic, which
 * involves filtering out spurious interrupts, keeping race-free blanking
 * counters, coping with counter wrap-around and resets and keeping use counts.
 * It relies on the driver to generate vertical blanking interrupts and
 * optionally provide a hardware vertical blanking counter.
 *
 * Drivers must initialize the vertical blanking handling core with a call to
 * drm_vblank_init(). Minimally, a driver needs to implement
 * &drm_crtc_funcs.enable_vblank and &drm_crtc_funcs.disable_vblank plus call
 * drm_crtc_handle_vblank() in its vblank interrupt handler for working vblank
 * support.
 *
 * Vertical blanking interrupts can be enabled by the DRM core or by drivers
 * themselves (for instance to handle page flipping operations).  The DRM core
 * maintains a vertical blanking use count to ensure that the interrupts are not
 * disabled while a user still needs them. To increment the use count, drivers
 * call drm_crtc_vblank_get() and release the vblank reference again with
 * drm_crtc_vblank_put(). In between these two calls vblank interrupts are
 * guaranteed to be enabled.
 *
 * On many hardware disabling the vblank interrupt cannot be done in a race-free
 * manner, see &drm_driver.vblank_disable_immediate and
 * &drm_driver.max_vblank_count. In that case the vblank core only disables the
 * vblanks after a timer has expired, which can be configured through the
 * ``vblankoffdelay`` module parameter.
 *
 * Drivers for hardware without support for vertical-blanking interrupts
 * must not call drm_vblank_init(). For such drivers, atomic helpers will
 * automatically generate fake vblank events as part of the display update.
 * This functionality also can be controlled by the driver by enabling and
 * disabling struct drm_crtc_state.no_vblank.
 */
 
/* Retry timestamp calculation up to 3 times to satisfy
 * drm_timestamp_precision before giving up.
 */
#define DRM_TIMESTAMP_MAXRETRIES 3
 
/* Threshold in nanoseconds for detection of redundant
 * vblank irq in drm_handle_vblank(). 1 msec should be ok.
 */
#define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
 
static bool
drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
<------><------><------>  ktime_t *tvblank, bool in_vblank_irq);
 
static unsigned int drm_timestamp_precision = 20;  /* Default to 20 usecs. */
 
static int drm_vblank_offdelay = 5000;    /* Default to 5000 msecs. */
 
module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600);
module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600);
MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)");
MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]");
 
static void store_vblank(struct drm_device *dev, unsigned int pipe,
<------><------><------> u32 vblank_count_inc,
<------><------><------> ktime_t t_vblank, u32 last)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>assert_spin_locked(&dev->vblank_time_lock);
 
<------>vblank->last = last;
 
<------>write_seqlock(&vblank->seqlock);
<------>vblank->time = t_vblank;
<------>atomic64_add(vblank_count_inc, &vblank->count);
<------>write_sequnlock(&vblank->seqlock);
}
 
static u32 drm_max_vblank_count(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>return vblank->max_vblank_count ?: dev->max_vblank_count;
}
 
/*
 * "No hw counter" fallback implementation of .get_vblank_counter() hook,
 * if there is no useable hardware frame counter available.
 */
static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe)
{
<------>drm_WARN_ON_ONCE(dev, drm_max_vblank_count(dev, pipe) != 0);
<------>return 0;
}
 
static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe)
{
<------>if (drm_core_check_feature(dev, DRIVER_MODESET)) {
<------><------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
 
<------><------>if (drm_WARN_ON(dev, !crtc))
<------><------><------>return 0;
 
<------><------>if (crtc->funcs->get_vblank_counter)
<------><------><------>return crtc->funcs->get_vblank_counter(crtc);
<------>} else if (dev->driver->get_vblank_counter) {
<------><------>return dev->driver->get_vblank_counter(dev, pipe);
<------>}
 
<------>return drm_vblank_no_hw_counter(dev, pipe);
}
 
/*
 * Reset the stored timestamp for the current vblank count to correspond
 * to the last vblank occurred.
 *
 * Only to be called from drm_crtc_vblank_on().
 *
 * Note: caller must hold &drm_device.vbl_lock since this reads & writes
 * device vblank fields.
 */
static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe)
{
<------>u32 cur_vblank;
<------>bool rc;
<------>ktime_t t_vblank;
<------>int count = DRM_TIMESTAMP_MAXRETRIES;
 
<------>spin_lock(&dev->vblank_time_lock);
 
<------>/*
<------> * sample the current counter to avoid random jumps
<------> * when drm_vblank_enable() applies the diff
<------> */
<------>do {
<------><------>cur_vblank = __get_vblank_counter(dev, pipe);
<------><------>rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
<------>} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
 
<------>/*
<------> * Only reinitialize corresponding vblank timestamp if high-precision query
<------> * available and didn't fail. Otherwise reinitialize delayed at next vblank
<------> * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid.
<------> */
<------>if (!rc)
<------><------>t_vblank = 0;
 
<------>/*
<------> * +1 to make sure user will never see the same
<------> * vblank counter value before and after a modeset
<------> */
<------>store_vblank(dev, pipe, 1, t_vblank, cur_vblank);
 
<------>spin_unlock(&dev->vblank_time_lock);
}
 
/*
 * Call back into the driver to update the appropriate vblank counter
 * (specified by @pipe).  Deal with wraparound, if it occurred, and
 * update the last read value so we can deal with wraparound on the next
 * call if necessary.
 *
 * Only necessary when going from off->on, to account for frames we
 * didn't get an interrupt for.
 *
 * Note: caller must hold &drm_device.vbl_lock since this reads & writes
 * device vblank fields.
 */
static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
<------><------><------><------>    bool in_vblank_irq)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>u32 cur_vblank, diff;
<------>bool rc;
<------>ktime_t t_vblank;
<------>int count = DRM_TIMESTAMP_MAXRETRIES;
<------>int framedur_ns = vblank->framedur_ns;
<------>u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
 
<------>/*
<------> * Interrupts were disabled prior to this call, so deal with counter
<------> * wrap if needed.
<------> * NOTE!  It's possible we lost a full dev->max_vblank_count + 1 events
<------> * here if the register is small or we had vblank interrupts off for
<------> * a long time.
<------> *
<------> * We repeat the hardware vblank counter & timestamp query until
<------> * we get consistent results. This to prevent races between gpu
<------> * updating its hardware counter while we are retrieving the
<------> * corresponding vblank timestamp.
<------> */
<------>do {
<------><------>cur_vblank = __get_vblank_counter(dev, pipe);
<------><------>rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq);
<------>} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
 
<------>if (max_vblank_count) {
<------><------>/* trust the hw counter when it's around */
<------><------>diff = (cur_vblank - vblank->last) & max_vblank_count;
<------>} else if (rc && framedur_ns) {
<------><------>u64 diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
 
<------><------>/*
<------><------> * Figure out how many vblanks we've missed based
<------><------> * on the difference in the timestamps and the
<------><------> * frame/field duration.
<------><------> */
 
<------><------>drm_dbg_vbl(dev, "crtc %u: Calculating number of vblanks."
<------><------><------>    " diff_ns = %lld, framedur_ns = %d)\n",
<------><------><------>    pipe, (long long)diff_ns, framedur_ns);
 
<------><------>diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
 
<------><------>if (diff == 0 && in_vblank_irq)
<------><------><------>drm_dbg_vbl(dev, "crtc %u: Redundant vblirq ignored\n",
<------><------><------><------>    pipe);
<------>} else {
<------><------>/* some kind of default for drivers w/o accurate vbl timestamping */
<------><------>diff = in_vblank_irq ? 1 : 0;
<------>}
 
<------>/*
<------> * Within a drm_vblank_pre_modeset - drm_vblank_post_modeset
<------> * interval? If so then vblank irqs keep running and it will likely
<------> * happen that the hardware vblank counter is not trustworthy as it
<------> * might reset at some point in that interval and vblank timestamps
<------> * are not trustworthy either in that interval. Iow. this can result
<------> * in a bogus diff >> 1 which must be avoided as it would cause
<------> * random large forward jumps of the software vblank counter.
<------> */
<------>if (diff > 1 && (vblank->inmodeset & 0x2)) {
<------><------>drm_dbg_vbl(dev,
<------><------><------>    "clamping vblank bump to 1 on crtc %u: diffr=%u"
<------><------><------>    " due to pre-modeset.\n", pipe, diff);
<------><------>diff = 1;
<------>}
 
<------>drm_dbg_vbl(dev, "updating vblank count on crtc %u:"
<------><------>    " current=%llu, diff=%u, hw=%u hw_last=%u\n",
<------><------>    pipe, (unsigned long long)atomic64_read(&vblank->count),
<------><------>    diff, cur_vblank, vblank->last);
 
<------>if (diff == 0) {
<------><------>drm_WARN_ON_ONCE(dev, cur_vblank != vblank->last);
<------><------>return;
<------>}
 
<------>/*
<------> * Only reinitialize corresponding vblank timestamp if high-precision query
<------> * available and didn't fail, or we were called from the vblank interrupt.
<------> * Otherwise reinitialize delayed at next vblank interrupt and assign 0
<------> * for now, to mark the vblanktimestamp as invalid.
<------> */
<------>if (!rc && !in_vblank_irq)
<------><------>t_vblank = 0;
 
<------>store_vblank(dev, pipe, diff, t_vblank, cur_vblank);
}
 
u64 drm_vblank_count(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>u64 count;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return 0;
 
<------>count = atomic64_read(&vblank->count);
 
<------>/*
<------> * This read barrier corresponds to the implicit write barrier of the
<------> * write seqlock in store_vblank(). Note that this is the only place
<------> * where we need an explicit barrier, since all other access goes
<------> * through drm_vblank_count_and_time(), which already has the required
<------> * read barrier curtesy of the read seqlock.
<------> */
<------>smp_rmb();
 
<------>return count;
}
 
/**
 * drm_crtc_accurate_vblank_count - retrieve the master vblank counter
 * @crtc: which counter to retrieve
 *
 * This function is similar to drm_crtc_vblank_count() but this function
 * interpolates to handle a race with vblank interrupts using the high precision
 * timestamping support.
 *
 * This is mostly useful for hardware that can obtain the scanout position, but
 * doesn't have a hardware frame counter.
 */
u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>u64 vblank;
<------>unsigned long flags;
 
<------>drm_WARN_ONCE(dev, drm_debug_enabled(DRM_UT_VBL) &&
<------><------>      !crtc->funcs->get_vblank_timestamp,
<------><------>      "This function requires support for accurate vblank timestamps.");
 
<------>spin_lock_irqsave(&dev->vblank_time_lock, flags);
 
<------>drm_update_vblank_count(dev, pipe, false);
<------>vblank = drm_vblank_count(dev, pipe);
 
<------>spin_unlock_irqrestore(&dev->vblank_time_lock, flags);
 
<------>return vblank;
}
EXPORT_SYMBOL(drm_crtc_accurate_vblank_count);
 
static void __disable_vblank(struct drm_device *dev, unsigned int pipe)
{
<------>if (drm_core_check_feature(dev, DRIVER_MODESET)) {
<------><------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
 
<------><------>if (drm_WARN_ON(dev, !crtc))
<------><------><------>return;
 
<------><------>if (crtc->funcs->disable_vblank)
<------><------><------>crtc->funcs->disable_vblank(crtc);
<------>} else {
<------><------>dev->driver->disable_vblank(dev, pipe);
<------>}
}
 
/*
 * Disable vblank irq's on crtc, make sure that last vblank count
 * of hardware and corresponding consistent software vblank counter
 * are preserved, even if there are any spurious vblank irq's after
 * disable.
 */
void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>unsigned long irqflags;
 
<------>assert_spin_locked(&dev->vbl_lock);
 
<------>/* Prevent vblank irq processing while disabling vblank irqs,
<------> * so no updates of timestamps or count can happen after we've
<------> * disabled. Needed to prevent races in case of delayed irq's.
<------> */
<------>spin_lock_irqsave(&dev->vblank_time_lock, irqflags);
 
<------>/*
<------> * Update vblank count and disable vblank interrupts only if the
<------> * interrupts were enabled. This avoids calling the ->disable_vblank()
<------> * operation in atomic context with the hardware potentially runtime
<------> * suspended.
<------> */
<------>if (!vblank->enabled)
<------><------>goto out;
 
<------>/*
<------> * Update the count and timestamp to maintain the
<------> * appearance that the counter has been ticking all along until
<------> * this time. This makes the count account for the entire time
<------> * between drm_crtc_vblank_on() and drm_crtc_vblank_off().
<------> */
<------>drm_update_vblank_count(dev, pipe, false);
<------>__disable_vblank(dev, pipe);
<------>vblank->enabled = false;
 
out:
<------>spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags);
}
 
static void vblank_disable_fn(struct timer_list *t)
{
<------>struct drm_vblank_crtc *vblank = from_timer(vblank, t, disable_timer);
<------>struct drm_device *dev = vblank->dev;
<------>unsigned int pipe = vblank->pipe;
<------>unsigned long irqflags;
 
<------>spin_lock_irqsave(&dev->vbl_lock, irqflags);
<------>if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) {
<------><------>drm_dbg_core(dev, "disabling vblank on crtc %u\n", pipe);
<------><------>drm_vblank_disable_and_save(dev, pipe);
<------>}
<------>spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
}
 
static void drm_vblank_init_release(struct drm_device *dev, void *ptr)
{
<------>struct drm_vblank_crtc *vblank = ptr;
 
<------>drm_WARN_ON(dev, READ_ONCE(vblank->enabled) &&
<------><------>    drm_core_check_feature(dev, DRIVER_MODESET));
 
<------>drm_vblank_destroy_worker(vblank);
<------>del_timer_sync(&vblank->disable_timer);
}
 
/**
 * drm_vblank_init - initialize vblank support
 * @dev: DRM device
 * @num_crtcs: number of CRTCs supported by @dev
 *
 * This function initializes vblank support for @num_crtcs display pipelines.
 * Cleanup is handled automatically through a cleanup function added with
 * drmm_add_action_or_reset().
 *
 * Returns:
 * Zero on success or a negative error code on failure.
 */
int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs)
{
<------>int ret;
<------>unsigned int i;
 
<------>spin_lock_init(&dev->vbl_lock);
<------>spin_lock_init(&dev->vblank_time_lock);
 
<------>dev->vblank = drmm_kcalloc(dev, num_crtcs, sizeof(*dev->vblank), GFP_KERNEL);
<------>if (!dev->vblank)
<------><------>return -ENOMEM;
 
<------>dev->num_crtcs = num_crtcs;
 
<------>for (i = 0; i < num_crtcs; i++) {
<------><------>struct drm_vblank_crtc *vblank = &dev->vblank[i];
 
<------><------>vblank->dev = dev;
<------><------>vblank->pipe = i;
<------><------>init_waitqueue_head(&vblank->queue);
<------><------>timer_setup(&vblank->disable_timer, vblank_disable_fn, 0);
<------><------>seqlock_init(&vblank->seqlock);
 
<------><------>ret = drmm_add_action_or_reset(dev, drm_vblank_init_release,
<------><------><------><------><------>       vblank);
<------><------>if (ret)
<------><------><------>return ret;
 
<------><------>ret = drm_vblank_worker_init(vblank);
<------><------>if (ret)
<------><------><------>return ret;
<------>}
 
<------>return 0;
}
EXPORT_SYMBOL(drm_vblank_init);
 
/**
 * drm_dev_has_vblank - test if vblanking has been initialized for
 *                      a device
 * @dev: the device
 *
 * Drivers may call this function to test if vblank support is
 * initialized for a device. For most hardware this means that vblanking
 * can also be enabled.
 *
 * Atomic helpers use this function to initialize
 * &drm_crtc_state.no_vblank. See also drm_atomic_helper_check_modeset().
 *
 * Returns:
 * True if vblanking has been initialized for the given device, false
 * otherwise.
 */
bool drm_dev_has_vblank(const struct drm_device *dev)
{
<------>return dev->num_crtcs != 0;
}
EXPORT_SYMBOL(drm_dev_has_vblank);
 
/**
 * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC
 * @crtc: which CRTC's vblank waitqueue to retrieve
 *
 * This function returns a pointer to the vblank waitqueue for the CRTC.
 * Drivers can use this to implement vblank waits using wait_event() and related
 * functions.
 */
wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc)
{
<------>return &crtc->dev->vblank[drm_crtc_index(crtc)].queue;
}
EXPORT_SYMBOL(drm_crtc_vblank_waitqueue);
 
 
/**
 * drm_calc_timestamping_constants - calculate vblank timestamp constants
 * @crtc: drm_crtc whose timestamp constants should be updated.
 * @mode: display mode containing the scanout timings
 *
 * Calculate and store various constants which are later needed by vblank and
 * swap-completion timestamping, e.g, by
 * drm_crtc_vblank_helper_get_vblank_timestamp(). They are derived from
 * CRTC's true scanout timing, so they take things like panel scaling or
 * other adjustments into account.
 */
void drm_calc_timestamping_constants(struct drm_crtc *crtc,
<------><------><------><------>     const struct drm_display_mode *mode)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>int linedur_ns = 0, framedur_ns = 0;
<------>int dotclock = mode->crtc_clock;
 
<------>if (!drm_dev_has_vblank(dev))
<------><------>return;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>/* Valid dotclock? */
<------>if (dotclock > 0) {
<------><------>int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
 
<------><------>/*
<------><------> * Convert scanline length in pixels and video
<------><------> * dot clock to line duration and frame duration
<------><------> * in nanoseconds:
<------><------> */
<------><------>linedur_ns  = div_u64((u64) mode->crtc_htotal * 1000000, dotclock);
<------><------>framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
 
<------><------>/*
<------><------> * Fields of interlaced scanout modes are only half a frame duration.
<------><------> */
<------><------>if (mode->flags & DRM_MODE_FLAG_INTERLACE)
<------><------><------>framedur_ns /= 2;
<------>} else {
<------><------>drm_err(dev, "crtc %u: Can't calculate constants, dotclock = 0!\n",
<------><------><------>crtc->base.id);
<------>}
 
<------>vblank->linedur_ns  = linedur_ns;
<------>vblank->framedur_ns = framedur_ns;
<------>vblank->hwmode = *mode;
 
<------>drm_dbg_core(dev,
<------><------>     "crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
<------><------>     crtc->base.id, mode->crtc_htotal,
<------><------>     mode->crtc_vtotal, mode->crtc_vdisplay);
<------>drm_dbg_core(dev, "crtc %u: clock %d kHz framedur %d linedur %d\n",
<------><------>     crtc->base.id, dotclock, framedur_ns, linedur_ns);
}
EXPORT_SYMBOL(drm_calc_timestamping_constants);
 
/**
 * drm_crtc_vblank_helper_get_vblank_timestamp_internal - precise vblank
 *                                                        timestamp helper
 * @crtc: CRTC whose vblank timestamp to retrieve
 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
 *             On return contains true maximum error of timestamp
 * @vblank_time: Pointer to time which should receive the timestamp
 * @in_vblank_irq:
 *     True when called from drm_crtc_handle_vblank().  Some drivers
 *     need to apply some workarounds for gpu-specific vblank irq quirks
 *     if flag is set.
 * @get_scanout_position:
 *     Callback function to retrieve the scanout position. See
 *     @struct drm_crtc_helper_funcs.get_scanout_position.
 *
 * Implements calculation of exact vblank timestamps from given drm_display_mode
 * timings and current video scanout position of a CRTC.
 *
 * The current implementation only handles standard video modes. For double scan
 * and interlaced modes the driver is supposed to adjust the hardware mode
 * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to
 * match the scanout position reported.
 *
 * Note that atomic drivers must call drm_calc_timestamping_constants() before
 * enabling a CRTC. The atomic helpers already take care of that in
 * drm_atomic_helper_calc_timestamping_constants().
 *
 * Returns:
 *
 * Returns true on success, and false on failure, i.e. when no accurate
 * timestamp could be acquired.
 */
bool
drm_crtc_vblank_helper_get_vblank_timestamp_internal(
<------>struct drm_crtc *crtc, int *max_error, ktime_t *vblank_time,
<------>bool in_vblank_irq,
<------>drm_vblank_get_scanout_position_func get_scanout_position)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = crtc->index;
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>struct timespec64 ts_etime, ts_vblank_time;
<------>ktime_t stime, etime;
<------>bool vbl_status;
<------>const struct drm_display_mode *mode;
<------>int vpos, hpos, i;
<------>int delta_ns, duration_ns;
 
<------>if (pipe >= dev->num_crtcs) {
<------><------>drm_err(dev, "Invalid crtc %u\n", pipe);
<------><------>return false;
<------>}
 
<------>/* Scanout position query not supported? Should not happen. */
<------>if (!get_scanout_position) {
<------><------>drm_err(dev, "Called from CRTC w/o get_scanout_position()!?\n");
<------><------>return false;
<------>}
 
<------>if (drm_drv_uses_atomic_modeset(dev))
<------><------>mode = &vblank->hwmode;
<------>else
<------><------>mode = &crtc->hwmode;
 
<------>/* If mode timing undefined, just return as no-op:
<------> * Happens during initial modesetting of a crtc.
<------> */
<------>if (mode->crtc_clock == 0) {
<------><------>drm_dbg_core(dev, "crtc %u: Noop due to uninitialized mode.\n",
<------><------><------>     pipe);
<------><------>drm_WARN_ON_ONCE(dev, drm_drv_uses_atomic_modeset(dev));
<------><------>return false;
<------>}
 
<------>/* Get current scanout position with system timestamp.
<------> * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times
<------> * if single query takes longer than max_error nanoseconds.
<------> *
<------> * This guarantees a tight bound on maximum error if
<------> * code gets preempted or delayed for some reason.
<------> */
<------>for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) {
<------><------>/*
<------><------> * Get vertical and horizontal scanout position vpos, hpos,
<------><------> * and bounding timestamps stime, etime, pre/post query.
<------><------> */
<------><------>vbl_status = get_scanout_position(crtc, in_vblank_irq,
<------><------><------><------><------><------>  &vpos, &hpos,
<------><------><------><------><------><------>  &stime, &etime,
<------><------><------><------><------><------>  mode);
 
<------><------>/* Return as no-op if scanout query unsupported or failed. */
<------><------>if (!vbl_status) {
<------><------><------>drm_dbg_core(dev,
<------><------><------><------>     "crtc %u : scanoutpos query failed.\n",
<------><------><------><------>     pipe);
<------><------><------>return false;
<------><------>}
 
<------><------>/* Compute uncertainty in timestamp of scanout position query. */
<------><------>duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime);
 
<------><------>/* Accept result with <  max_error nsecs timing uncertainty. */
<------><------>if (duration_ns <= *max_error)
<------><------><------>break;
<------>}
 
<------>/* Noisy system timing? */
<------>if (i == DRM_TIMESTAMP_MAXRETRIES) {
<------><------>drm_dbg_core(dev,
<------><------><------>     "crtc %u: Noisy timestamp %d us > %d us [%d reps].\n",
<------><------><------>     pipe, duration_ns / 1000, *max_error / 1000, i);
<------>}
 
<------>/* Return upper bound of timestamp precision error. */
<------>*max_error = duration_ns;
 
<------>/* Convert scanout position into elapsed time at raw_time query
<------> * since start of scanout at first display scanline. delta_ns
<------> * can be negative if start of scanout hasn't happened yet.
<------> */
<------>delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos),
<------><------><------>   mode->crtc_clock);
 
<------>/* Subtract time delta from raw timestamp to get final
<------> * vblank_time timestamp for end of vblank.
<------> */
<------>*vblank_time = ktime_sub_ns(etime, delta_ns);
 
<------>if (!drm_debug_enabled(DRM_UT_VBL))
<------><------>return true;
 
<------>ts_etime = ktime_to_timespec64(etime);
<------>ts_vblank_time = ktime_to_timespec64(*vblank_time);
 
<------>drm_dbg_vbl(dev,
<------><------>    "crtc %u : v p(%d,%d)@ %lld.%06ld -> %lld.%06ld [e %d us, %d rep]\n",
<------><------>    pipe, hpos, vpos,
<------><------>    (u64)ts_etime.tv_sec, ts_etime.tv_nsec / 1000,
<------><------>    (u64)ts_vblank_time.tv_sec, ts_vblank_time.tv_nsec / 1000,
<------><------>    duration_ns / 1000, i);
 
<------>return true;
}
EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp_internal);
 
/**
 * drm_crtc_vblank_helper_get_vblank_timestamp - precise vblank timestamp
 *                                               helper
 * @crtc: CRTC whose vblank timestamp to retrieve
 * @max_error: Desired maximum allowable error in timestamps (nanosecs)
 *             On return contains true maximum error of timestamp
 * @vblank_time: Pointer to time which should receive the timestamp
 * @in_vblank_irq:
 *     True when called from drm_crtc_handle_vblank().  Some drivers
 *     need to apply some workarounds for gpu-specific vblank irq quirks
 *     if flag is set.
 *
 * Implements calculation of exact vblank timestamps from given drm_display_mode
 * timings and current video scanout position of a CRTC. This can be directly
 * used as the &drm_crtc_funcs.get_vblank_timestamp implementation of a kms
 * driver if &drm_crtc_helper_funcs.get_scanout_position is implemented.
 *
 * The current implementation only handles standard video modes. For double scan
 * and interlaced modes the driver is supposed to adjust the hardware mode
 * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to
 * match the scanout position reported.
 *
 * Note that atomic drivers must call drm_calc_timestamping_constants() before
 * enabling a CRTC. The atomic helpers already take care of that in
 * drm_atomic_helper_calc_timestamping_constants().
 *
 * Returns:
 *
 * Returns true on success, and false on failure, i.e. when no accurate
 * timestamp could be acquired.
 */
bool drm_crtc_vblank_helper_get_vblank_timestamp(struct drm_crtc *crtc,
<------><------><------><------><------><------> int *max_error,
<------><------><------><------><------><------> ktime_t *vblank_time,
<------><------><------><------><------><------> bool in_vblank_irq)
{
<------>return drm_crtc_vblank_helper_get_vblank_timestamp_internal(
<------><------>crtc, max_error, vblank_time, in_vblank_irq,
<------><------>crtc->helper_private->get_scanout_position);
}
EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp);
 
/**
 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent
 *                             vblank interval
 * @dev: DRM device
 * @pipe: index of CRTC whose vblank timestamp to retrieve
 * @tvblank: Pointer to target time which should receive the timestamp
 * @in_vblank_irq:
 *     True when called from drm_crtc_handle_vblank().  Some drivers
 *     need to apply some workarounds for gpu-specific vblank irq quirks
 *     if flag is set.
 *
 * Fetches the system timestamp corresponding to the time of the most recent
 * vblank interval on specified CRTC. May call into kms-driver to
 * compute the timestamp with a high-precision GPU specific method.
 *
 * Returns zero if timestamp originates from uncorrected do_gettimeofday()
 * call, i.e., it isn't very precisely locked to the true vblank.
 *
 * Returns:
 * True if timestamp is considered to be very precise, false otherwise.
 */
static bool
drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
<------><------><------>  ktime_t *tvblank, bool in_vblank_irq)
{
<------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
<------>bool ret = false;
 
<------>/* Define requested maximum error on timestamps (nanoseconds). */
<------>int max_error = (int) drm_timestamp_precision * 1000;
 
<------>/* Query driver if possible and precision timestamping enabled. */
<------>if (crtc && crtc->funcs->get_vblank_timestamp && max_error > 0) {
<------><------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
 
<------><------>ret = crtc->funcs->get_vblank_timestamp(crtc, &max_error,
<------><------><------><------><------><------><------>tvblank, in_vblank_irq);
<------>}
 
<------>/* GPU high precision timestamp query unsupported or failed.
<------> * Return current monotonic/gettimeofday timestamp as best estimate.
<------> */
<------>if (!ret)
<------><------>*tvblank = ktime_get();
 
<------>return ret;
}
 
/**
 * drm_crtc_vblank_count - retrieve "cooked" vblank counter value
 * @crtc: which counter to retrieve
 *
 * Fetches the "cooked" vblank count value that represents the number of
 * vblank events since the system was booted, including lost events due to
 * modesetting activity. Note that this timer isn't correct against a racing
 * vblank interrupt (since it only reports the software vblank counter), see
 * drm_crtc_accurate_vblank_count() for such use-cases.
 *
 * Note that for a given vblank counter value drm_crtc_handle_vblank()
 * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time()
 * provide a barrier: Any writes done before calling
 * drm_crtc_handle_vblank() will be visible to callers of the later
 * functions, iff the vblank count is the same or a later one.
 *
 * See also &drm_vblank_crtc.count.
 *
 * Returns:
 * The software vblank counter.
 */
u64 drm_crtc_vblank_count(struct drm_crtc *crtc)
{
<------>return drm_vblank_count(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_count);
 
/**
 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the
 *     system timestamp corresponding to that vblank counter value.
 * @dev: DRM device
 * @pipe: index of CRTC whose counter to retrieve
 * @vblanktime: Pointer to ktime_t to receive the vblank timestamp.
 *
 * Fetches the "cooked" vblank count value that represents the number of
 * vblank events since the system was booted, including lost events due to
 * modesetting activity. Returns corresponding system timestamp of the time
 * of the vblank interval that corresponds to the current vblank counter value.
 *
 * This is the legacy version of drm_crtc_vblank_count_and_time().
 */
static u64 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
<------><------><------><------>     ktime_t *vblanktime)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>u64 vblank_count;
<------>unsigned int seq;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) {
<------><------>*vblanktime = 0;
<------><------>return 0;
<------>}
 
<------>do {
<------><------>seq = read_seqbegin(&vblank->seqlock);
<------><------>vblank_count = atomic64_read(&vblank->count);
<------><------>*vblanktime = vblank->time;
<------>} while (read_seqretry(&vblank->seqlock, seq));
 
<------>return vblank_count;
}
 
/**
 * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value
 *     and the system timestamp corresponding to that vblank counter value
 * @crtc: which counter to retrieve
 * @vblanktime: Pointer to time to receive the vblank timestamp.
 *
 * Fetches the "cooked" vblank count value that represents the number of
 * vblank events since the system was booted, including lost events due to
 * modesetting activity. Returns corresponding system timestamp of the time
 * of the vblank interval that corresponds to the current vblank counter value.
 *
 * Note that for a given vblank counter value drm_crtc_handle_vblank()
 * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time()
 * provide a barrier: Any writes done before calling
 * drm_crtc_handle_vblank() will be visible to callers of the later
 * functions, iff the vblank count is the same or a later one.
 *
 * See also &drm_vblank_crtc.count.
 */
u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
<------><------><------><------>   ktime_t *vblanktime)
{
<------>return drm_vblank_count_and_time(crtc->dev, drm_crtc_index(crtc),
<------><------><------><------><------> vblanktime);
}
EXPORT_SYMBOL(drm_crtc_vblank_count_and_time);
 
static void send_vblank_event(struct drm_device *dev,
<------><------>struct drm_pending_vblank_event *e,
<------><------>u64 seq, ktime_t now)
{
<------>struct timespec64 tv;
 
<------>switch (e->event.base.type) {
<------>case DRM_EVENT_VBLANK:
<------>case DRM_EVENT_FLIP_COMPLETE:
<------><------>tv = ktime_to_timespec64(now);
<------><------>e->event.vbl.sequence = seq;
<------><------>/*
<------><------> * e->event is a user space structure, with hardcoded unsigned
<------><------> * 32-bit seconds/microseconds. This is safe as we always use
<------><------> * monotonic timestamps since linux-4.15
<------><------> */
<------><------>e->event.vbl.tv_sec = tv.tv_sec;
<------><------>e->event.vbl.tv_usec = tv.tv_nsec / 1000;
<------><------>break;
<------>case DRM_EVENT_CRTC_SEQUENCE:
<------><------>if (seq)
<------><------><------>e->event.seq.sequence = seq;
<------><------>e->event.seq.time_ns = ktime_to_ns(now);
<------><------>break;
<------>}
<------>trace_drm_vblank_event_delivered(e->base.file_priv, e->pipe, seq);
<------>/*
<------> * Use the same timestamp for any associated fence signal to avoid
<------> * mismatch in timestamps for vsync & fence events triggered by the
<------> * same HW event. Frameworks like SurfaceFlinger in Android expects the
<------> * retire-fence timestamp to match exactly with HW vsync as it uses it
<------> * for its software vsync modeling.
<------> */
<------>drm_send_event_timestamp_locked(dev, &e->base, now);
}
 
/**
 * drm_crtc_arm_vblank_event - arm vblank event after pageflip
 * @crtc: the source CRTC of the vblank event
 * @e: the event to send
 *
 * A lot of drivers need to generate vblank events for the very next vblank
 * interrupt. For example when the page flip interrupt happens when the page
 * flip gets armed, but not when it actually executes within the next vblank
 * period. This helper function implements exactly the required vblank arming
 * behaviour.
 *
 * NOTE: Drivers using this to send out the &drm_crtc_state.event as part of an
 * atomic commit must ensure that the next vblank happens at exactly the same
 * time as the atomic commit is committed to the hardware. This function itself
 * does **not** protect against the next vblank interrupt racing with either this
 * function call or the atomic commit operation. A possible sequence could be:
 *
 * 1. Driver commits new hardware state into vblank-synchronized registers.
 * 2. A vblank happens, committing the hardware state. Also the corresponding
 *    vblank interrupt is fired off and fully processed by the interrupt
 *    handler.
 * 3. The atomic commit operation proceeds to call drm_crtc_arm_vblank_event().
 * 4. The event is only send out for the next vblank, which is wrong.
 *
 * An equivalent race can happen when the driver calls
 * drm_crtc_arm_vblank_event() before writing out the new hardware state.
 *
 * The only way to make this work safely is to prevent the vblank from firing
 * (and the hardware from committing anything else) until the entire atomic
 * commit sequence has run to completion. If the hardware does not have such a
 * feature (e.g. using a "go" bit), then it is unsafe to use this functions.
 * Instead drivers need to manually send out the event from their interrupt
 * handler by calling drm_crtc_send_vblank_event() and make sure that there's no
 * possible race with the hardware committing the atomic update.
 *
 * Caller must hold a vblank reference for the event @e acquired by a
 * drm_crtc_vblank_get(), which will be dropped when the next vblank arrives.
 */
void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
<------><------><------>       struct drm_pending_vblank_event *e)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
 
<------>assert_spin_locked(&dev->event_lock);
 
<------>e->pipe = pipe;
<------>e->sequence = drm_crtc_accurate_vblank_count(crtc) + 1;
<------>list_add_tail(&e->base.link, &dev->vblank_event_list);
}
EXPORT_SYMBOL(drm_crtc_arm_vblank_event);
 
/**
 * drm_crtc_send_vblank_event - helper to send vblank event after pageflip
 * @crtc: the source CRTC of the vblank event
 * @e: the event to send
 *
 * Updates sequence # and timestamp on event for the most recently processed
 * vblank, and sends it to userspace.  Caller must hold event lock.
 *
 * See drm_crtc_arm_vblank_event() for a helper which can be used in certain
 * situation, especially to send out events for atomic commit operations.
 */
void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
<------><------><------><------>struct drm_pending_vblank_event *e)
{
<------>struct drm_device *dev = crtc->dev;
<------>u64 seq;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>ktime_t now;
 
<------>if (drm_dev_has_vblank(dev)) {
<------><------>seq = drm_vblank_count_and_time(dev, pipe, &now);
<------>} else {
<------><------>seq = 0;
 
<------><------>now = ktime_get();
<------>}
<------>e->pipe = pipe;
<------>send_vblank_event(dev, e, seq, now);
}
EXPORT_SYMBOL(drm_crtc_send_vblank_event);
 
static int __enable_vblank(struct drm_device *dev, unsigned int pipe)
{
<------>if (drm_core_check_feature(dev, DRIVER_MODESET)) {
<------><------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
 
<------><------>if (drm_WARN_ON(dev, !crtc))
<------><------><------>return 0;
 
<------><------>if (crtc->funcs->enable_vblank)
<------><------><------>return crtc->funcs->enable_vblank(crtc);
<------>} else if (dev->driver->enable_vblank) {
<------><------>return dev->driver->enable_vblank(dev, pipe);
<------>}
 
<------>return -EINVAL;
}
 
static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>int ret = 0;
 
<------>assert_spin_locked(&dev->vbl_lock);
 
<------>spin_lock(&dev->vblank_time_lock);
 
<------>if (!vblank->enabled) {
<------><------>/*
<------><------> * Enable vblank irqs under vblank_time_lock protection.
<------><------> * All vblank count & timestamp updates are held off
<------><------> * until we are done reinitializing master counter and
<------><------> * timestamps. Filtercode in drm_handle_vblank() will
<------><------> * prevent double-accounting of same vblank interval.
<------><------> */
<------><------>ret = __enable_vblank(dev, pipe);
<------><------>drm_dbg_core(dev, "enabling vblank on crtc %u, ret: %d\n",
<------><------><------>     pipe, ret);
<------><------>if (ret) {
<------><------><------>atomic_dec(&vblank->refcount);
<------><------>} else {
<------><------><------>drm_update_vblank_count(dev, pipe, 0);
<------><------><------>/* drm_update_vblank_count() includes a wmb so we just
<------><------><------> * need to ensure that the compiler emits the write
<------><------><------> * to mark the vblank as enabled after the call
<------><------><------> * to drm_update_vblank_count().
<------><------><------> */
<------><------><------>WRITE_ONCE(vblank->enabled, true);
<------><------>}
<------>}
 
<------>spin_unlock(&dev->vblank_time_lock);
 
<------>return ret;
}
 
int drm_vblank_get(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>unsigned long irqflags;
<------>int ret = 0;
 
<------>if (!drm_dev_has_vblank(dev))
<------><------>return -EINVAL;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return -EINVAL;
 
<------>spin_lock_irqsave(&dev->vbl_lock, irqflags);
<------>/* Going from 0->1 means we have to enable interrupts again */
<------>if (atomic_add_return(1, &vblank->refcount) == 1) {
<------><------>ret = drm_vblank_enable(dev, pipe);
<------>} else {
<------><------>if (!vblank->enabled) {
<------><------><------>atomic_dec(&vblank->refcount);
<------><------><------>ret = -EINVAL;
<------><------>}
<------>}
<------>spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 
<------>return ret;
}
 
/**
 * drm_crtc_vblank_get - get a reference count on vblank events
 * @crtc: which CRTC to own
 *
 * Acquire a reference count on vblank events to avoid having them disabled
 * while in use.
 *
 * Returns:
 * Zero on success or a negative error code on failure.
 */
int drm_crtc_vblank_get(struct drm_crtc *crtc)
{
<------>return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_get);
 
void drm_vblank_put(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>if (drm_WARN_ON(dev, atomic_read(&vblank->refcount) == 0))
<------><------>return;
 
<------>/* Last user schedules interrupt disable */
<------>if (atomic_dec_and_test(&vblank->refcount)) {
<------><------>if (drm_vblank_offdelay == 0)
<------><------><------>return;
<------><------>else if (drm_vblank_offdelay < 0)
<------><------><------>vblank_disable_fn(&vblank->disable_timer);
<------><------>else if (!dev->vblank_disable_immediate)
<------><------><------>mod_timer(&vblank->disable_timer,
<------><------><------><------>  jiffies + ((drm_vblank_offdelay * HZ)/1000));
<------>}
}
 
/**
 * drm_crtc_vblank_put - give up ownership of vblank events
 * @crtc: which counter to give up
 *
 * Release ownership of a given vblank counter, turning off interrupts
 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
 */
void drm_crtc_vblank_put(struct drm_crtc *crtc)
{
<------>drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_put);
 
/**
 * drm_wait_one_vblank - wait for one vblank
 * @dev: DRM device
 * @pipe: CRTC index
 *
 * This waits for one vblank to pass on @pipe, using the irq driver interfaces.
 * It is a failure to call this when the vblank irq for @pipe is disabled, e.g.
 * due to lack of driver support or because the crtc is off.
 *
 * This is the legacy version of drm_crtc_wait_one_vblank().
 */
void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>int ret;
<------>u64 last;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>ret = drm_vblank_get(dev, pipe);
<------>if (drm_WARN(dev, ret, "vblank not available on crtc %i, ret=%i\n",
<------><------>     pipe, ret))
<------><------>return;
 
<------>last = drm_vblank_count(dev, pipe);
 
<------>ret = wait_event_timeout(vblank->queue,
<------><------><------><------> last != drm_vblank_count(dev, pipe),
<------><------><------><------> msecs_to_jiffies(100));
 
<------>drm_WARN(dev, ret == 0, "vblank wait timed out on crtc %i\n", pipe);
 
<------>drm_vblank_put(dev, pipe);
}
EXPORT_SYMBOL(drm_wait_one_vblank);
 
/**
 * drm_crtc_wait_one_vblank - wait for one vblank
 * @crtc: DRM crtc
 *
 * This waits for one vblank to pass on @crtc, using the irq driver interfaces.
 * It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
 * due to lack of driver support or because the crtc is off.
 */
void drm_crtc_wait_one_vblank(struct drm_crtc *crtc)
{
<------>drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_wait_one_vblank);
 
/**
 * drm_crtc_vblank_off - disable vblank events on a CRTC
 * @crtc: CRTC in question
 *
 * Drivers can use this function to shut down the vblank interrupt handling when
 * disabling a crtc. This function ensures that the latest vblank frame count is
 * stored so that drm_vblank_on can restore it again.
 *
 * Drivers must use this function when the hardware vblank counter can get
 * reset, e.g. when suspending or disabling the @crtc in general.
 */
void drm_crtc_vblank_off(struct drm_crtc *crtc)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>struct drm_pending_vblank_event *e, *t;
<------>ktime_t now;
<------>u64 seq;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>/*
<------> * Grab event_lock early to prevent vblank work from being scheduled
<------> * while we're in the middle of shutting down vblank interrupts
<------> */
<------>spin_lock_irq(&dev->event_lock);
 
<------>spin_lock(&dev->vbl_lock);
<------>drm_dbg_vbl(dev, "crtc %d, vblank enabled %d, inmodeset %d\n",
<------><------>    pipe, vblank->enabled, vblank->inmodeset);
 
<------>/* Avoid redundant vblank disables without previous
<------> * drm_crtc_vblank_on(). */
<------>if (drm_core_check_feature(dev, DRIVER_ATOMIC) || !vblank->inmodeset)
<------><------>drm_vblank_disable_and_save(dev, pipe);
 
<------>wake_up(&vblank->queue);
 
<------>/*
<------> * Prevent subsequent drm_vblank_get() from re-enabling
<------> * the vblank interrupt by bumping the refcount.
<------> */
<------>if (!vblank->inmodeset) {
<------><------>atomic_inc(&vblank->refcount);
<------><------>vblank->inmodeset = 1;
<------>}
<------>spin_unlock(&dev->vbl_lock);
 
<------>/* Send any queued vblank events, lest the natives grow disquiet */
<------>seq = drm_vblank_count_and_time(dev, pipe, &now);
 
<------>list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
<------><------>if (e->pipe != pipe)
<------><------><------>continue;
<------><------>drm_dbg_core(dev, "Sending premature vblank event on disable: "
<------><------><------>     "wanted %llu, current %llu\n",
<------><------><------>     e->sequence, seq);
<------><------>list_del(&e->base.link);
<------><------>drm_vblank_put(dev, pipe);
<------><------>send_vblank_event(dev, e, seq, now);
<------>}
 
<------>/* Cancel any leftover pending vblank work */
<------>drm_vblank_cancel_pending_works(vblank);
 
<------>spin_unlock_irq(&dev->event_lock);
 
<------>/* Will be reset by the modeset helpers when re-enabling the crtc by
<------> * calling drm_calc_timestamping_constants(). */
<------>vblank->hwmode.crtc_clock = 0;
 
<------>/* Wait for any vblank work that's still executing to finish */
<------>drm_vblank_flush_worker(vblank);
}
EXPORT_SYMBOL(drm_crtc_vblank_off);
 
/**
 * drm_crtc_vblank_reset - reset vblank state to off on a CRTC
 * @crtc: CRTC in question
 *
 * Drivers can use this function to reset the vblank state to off at load time.
 * Drivers should use this together with the drm_crtc_vblank_off() and
 * drm_crtc_vblank_on() functions. The difference compared to
 * drm_crtc_vblank_off() is that this function doesn't save the vblank counter
 * and hence doesn't need to call any driver hooks.
 *
 * This is useful for recovering driver state e.g. on driver load, or on resume.
 */
void drm_crtc_vblank_reset(struct drm_crtc *crtc)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>spin_lock_irq(&dev->vbl_lock);
<------>/*
<------> * Prevent subsequent drm_vblank_get() from enabling the vblank
<------> * interrupt by bumping the refcount.
<------> */
<------>if (!vblank->inmodeset) {
<------><------>atomic_inc(&vblank->refcount);
<------><------>vblank->inmodeset = 1;
<------>}
<------>spin_unlock_irq(&dev->vbl_lock);
 
<------>drm_WARN_ON(dev, !list_empty(&dev->vblank_event_list));
<------>drm_WARN_ON(dev, !list_empty(&vblank->pending_work));
}
EXPORT_SYMBOL(drm_crtc_vblank_reset);
 
/**
 * drm_crtc_set_max_vblank_count - configure the hw max vblank counter value
 * @crtc: CRTC in question
 * @max_vblank_count: max hardware vblank counter value
 *
 * Update the maximum hardware vblank counter value for @crtc
 * at runtime. Useful for hardware where the operation of the
 * hardware vblank counter depends on the currently active
 * display configuration.
 *
 * For example, if the hardware vblank counter does not work
 * when a specific connector is active the maximum can be set
 * to zero. And when that specific connector isn't active the
 * maximum can again be set to the appropriate non-zero value.
 *
 * If used, must be called before drm_vblank_on().
 */
void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc,
<------><------><------><------>   u32 max_vblank_count)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>drm_WARN_ON(dev, dev->max_vblank_count);
<------>drm_WARN_ON(dev, !READ_ONCE(vblank->inmodeset));
 
<------>vblank->max_vblank_count = max_vblank_count;
}
EXPORT_SYMBOL(drm_crtc_set_max_vblank_count);
 
/**
 * drm_crtc_vblank_on - enable vblank events on a CRTC
 * @crtc: CRTC in question
 *
 * This functions restores the vblank interrupt state captured with
 * drm_crtc_vblank_off() again and is generally called when enabling @crtc. Note
 * that calls to drm_crtc_vblank_on() and drm_crtc_vblank_off() can be
 * unbalanced and so can also be unconditionally called in driver load code to
 * reflect the current hardware state of the crtc.
 */
void drm_crtc_vblank_on(struct drm_crtc *crtc)
{
<------>struct drm_device *dev = crtc->dev;
<------>unsigned int pipe = drm_crtc_index(crtc);
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>spin_lock_irq(&dev->vbl_lock);
<------>drm_dbg_vbl(dev, "crtc %d, vblank enabled %d, inmodeset %d\n",
<------><------>    pipe, vblank->enabled, vblank->inmodeset);
 
<------>/* Drop our private "prevent drm_vblank_get" refcount */
<------>if (vblank->inmodeset) {
<------><------>atomic_dec(&vblank->refcount);
<------><------>vblank->inmodeset = 0;
<------>}
 
<------>drm_reset_vblank_timestamp(dev, pipe);
 
<------>/*
<------> * re-enable interrupts if there are users left, or the
<------> * user wishes vblank interrupts to be enabled all the time.
<------> */
<------>if (atomic_read(&vblank->refcount) != 0 || drm_vblank_offdelay == 0)
<------><------>drm_WARN_ON(dev, drm_vblank_enable(dev, pipe));
<------>spin_unlock_irq(&dev->vbl_lock);
}
EXPORT_SYMBOL(drm_crtc_vblank_on);
 
/**
 * drm_vblank_restore - estimate missed vblanks and update vblank count.
 * @dev: DRM device
 * @pipe: CRTC index
 *
 * Power manamement features can cause frame counter resets between vblank
 * disable and enable. Drivers can use this function in their
 * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
 * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
 * vblank counter.
 *
 * This function is the legacy version of drm_crtc_vblank_restore().
 */
void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
{
<------>ktime_t t_vblank;
<------>struct drm_vblank_crtc *vblank;
<------>int framedur_ns;
<------>u64 diff_ns;
<------>u32 cur_vblank, diff = 1;
<------>int count = DRM_TIMESTAMP_MAXRETRIES;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>assert_spin_locked(&dev->vbl_lock);
<------>assert_spin_locked(&dev->vblank_time_lock);
 
<------>vblank = &dev->vblank[pipe];
<------>drm_WARN_ONCE(dev,
<------><------>      drm_debug_enabled(DRM_UT_VBL) && !vblank->framedur_ns,
<------><------>      "Cannot compute missed vblanks without frame duration\n");
<------>framedur_ns = vblank->framedur_ns;
 
<------>do {
<------><------>cur_vblank = __get_vblank_counter(dev, pipe);
<------><------>drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
<------>} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
 
<------>diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
<------>if (framedur_ns)
<------><------>diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
 
 
<------>drm_dbg_vbl(dev,
<------><------>    "missed %d vblanks in %lld ns, frame duration=%d ns, hw_diff=%d\n",
<------><------>    diff, diff_ns, framedur_ns, cur_vblank - vblank->last);
<------>store_vblank(dev, pipe, diff, t_vblank, cur_vblank);
}
EXPORT_SYMBOL(drm_vblank_restore);
 
/**
 * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count.
 * @crtc: CRTC in question
 *
 * Power manamement features can cause frame counter resets between vblank
 * disable and enable. Drivers can use this function in their
 * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
 * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
 * vblank counter.
 */
void drm_crtc_vblank_restore(struct drm_crtc *crtc)
{
<------>drm_vblank_restore(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_restore);
 
static void drm_legacy_vblank_pre_modeset(struct drm_device *dev,
<------><------><------><------><------>  unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>/* vblank is not initialized (IRQ not installed ?), or has been freed */
<------>if (!drm_dev_has_vblank(dev))
<------><------>return;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>/*
<------> * To avoid all the problems that might happen if interrupts
<------> * were enabled/disabled around or between these calls, we just
<------> * have the kernel take a reference on the CRTC (just once though
<------> * to avoid corrupting the count if multiple, mismatch calls occur),
<------> * so that interrupts remain enabled in the interim.
<------> */
<------>if (!vblank->inmodeset) {
<------><------>vblank->inmodeset = 0x1;
<------><------>if (drm_vblank_get(dev, pipe) == 0)
<------><------><------>vblank->inmodeset |= 0x2;
<------>}
}
 
static void drm_legacy_vblank_post_modeset(struct drm_device *dev,
<------><------><------><------><------>   unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
 
<------>/* vblank is not initialized (IRQ not installed ?), or has been freed */
<------>if (!drm_dev_has_vblank(dev))
<------><------>return;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return;
 
<------>if (vblank->inmodeset) {
<------><------>spin_lock_irq(&dev->vbl_lock);
<------><------>drm_reset_vblank_timestamp(dev, pipe);
<------><------>spin_unlock_irq(&dev->vbl_lock);
 
<------><------>if (vblank->inmodeset & 0x2)
<------><------><------>drm_vblank_put(dev, pipe);
 
<------><------>vblank->inmodeset = 0;
<------>}
}
 
int drm_legacy_modeset_ctl_ioctl(struct drm_device *dev, void *data,
<------><------><------><------> struct drm_file *file_priv)
{
<------>struct drm_modeset_ctl *modeset = data;
<------>unsigned int pipe;
 
<------>/* If drm_vblank_init() hasn't been called yet, just no-op */
<------>if (!drm_dev_has_vblank(dev))
<------><------>return 0;
 
<------>/* KMS drivers handle this internally */
<------>if (!drm_core_check_feature(dev, DRIVER_LEGACY))
<------><------>return 0;
 
<------>pipe = modeset->crtc;
<------>if (pipe >= dev->num_crtcs)
<------><------>return -EINVAL;
 
<------>switch (modeset->cmd) {
<------>case _DRM_PRE_MODESET:
<------><------>drm_legacy_vblank_pre_modeset(dev, pipe);
<------><------>break;
<------>case _DRM_POST_MODESET:
<------><------>drm_legacy_vblank_post_modeset(dev, pipe);
<------><------>break;
<------>default:
<------><------>return -EINVAL;
<------>}
 
<------>return 0;
}
 
static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
<------><------><------><------>  u64 req_seq,
<------><------><------><------>  union drm_wait_vblank *vblwait,
<------><------><------><------>  struct drm_file *file_priv)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>struct drm_pending_vblank_event *e;
<------>ktime_t now;
<------>u64 seq;
<------>int ret;
 
<------>e = kzalloc(sizeof(*e), GFP_KERNEL);
<------>if (e == NULL) {
<------><------>ret = -ENOMEM;
<------><------>goto err_put;
<------>}
 
<------>e->pipe = pipe;
<------>e->event.base.type = DRM_EVENT_VBLANK;
<------>e->event.base.length = sizeof(e->event.vbl);
<------>e->event.vbl.user_data = vblwait->request.signal;
<------>e->event.vbl.crtc_id = 0;
<------>if (drm_core_check_feature(dev, DRIVER_MODESET)) {
<------><------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
 
<------><------>if (crtc)
<------><------><------>e->event.vbl.crtc_id = crtc->base.id;
<------>}
 
<------>spin_lock_irq(&dev->event_lock);
 
<------>/*
<------> * drm_crtc_vblank_off() might have been called after we called
<------> * drm_vblank_get(). drm_crtc_vblank_off() holds event_lock around the
<------> * vblank disable, so no need for further locking.  The reference from
<------> * drm_vblank_get() protects against vblank disable from another source.
<------> */
<------>if (!READ_ONCE(vblank->enabled)) {
<------><------>ret = -EINVAL;
<------><------>goto err_unlock;
<------>}
 
<------>ret = drm_event_reserve_init_locked(dev, file_priv, &e->base,
<------><------><------><------><------>    &e->event.base);
 
<------>if (ret)
<------><------>goto err_unlock;
 
<------>seq = drm_vblank_count_and_time(dev, pipe, &now);
 
<------>drm_dbg_core(dev, "event on vblank count %llu, current %llu, crtc %u\n",
<------><------>     req_seq, seq, pipe);
 
<------>trace_drm_vblank_event_queued(file_priv, pipe, req_seq);
 
<------>e->sequence = req_seq;
<------>if (drm_vblank_passed(seq, req_seq)) {
<------><------>drm_vblank_put(dev, pipe);
<------><------>send_vblank_event(dev, e, seq, now);
<------><------>vblwait->reply.sequence = seq;
<------>} else {
<------><------>/* drm_handle_vblank_events will call drm_vblank_put */
<------><------>list_add_tail(&e->base.link, &dev->vblank_event_list);
<------><------>vblwait->reply.sequence = req_seq;
<------>}
 
<------>spin_unlock_irq(&dev->event_lock);
 
<------>return 0;
 
err_unlock:
<------>spin_unlock_irq(&dev->event_lock);
<------>kfree(e);
err_put:
<------>drm_vblank_put(dev, pipe);
<------>return ret;
}
 
static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait)
{
<------>if (vblwait->request.sequence)
<------><------>return false;
 
<------>return _DRM_VBLANK_RELATIVE ==
<------><------>(vblwait->request.type & (_DRM_VBLANK_TYPES_MASK |
<------><------><------><------><------>  _DRM_VBLANK_EVENT |
<------><------><------><------><------>  _DRM_VBLANK_NEXTONMISS));
}
 
/*
 * Widen a 32-bit param to 64-bits.
 *
 * \param narrow 32-bit value (missing upper 32 bits)
 * \param near 64-bit value that should be 'close' to near
 *
 * This function returns a 64-bit value using the lower 32-bits from
 * 'narrow' and constructing the upper 32-bits so that the result is
 * as close as possible to 'near'.
 */
 
static u64 widen_32_to_64(u32 narrow, u64 near)
{
<------>return near + (s32) (narrow - near);
}
 
static void drm_wait_vblank_reply(struct drm_device *dev, unsigned int pipe,
<------><------><------><------>  struct drm_wait_vblank_reply *reply)
{
<------>ktime_t now;
<------>struct timespec64 ts;
 
<------>/*
<------> * drm_wait_vblank_reply is a UAPI structure that uses 'long'
<------> * to store the seconds. This is safe as we always use monotonic
<------> * timestamps since linux-4.15.
<------> */
<------>reply->sequence = drm_vblank_count_and_time(dev, pipe, &now);
<------>ts = ktime_to_timespec64(now);
<------>reply->tval_sec = (u32)ts.tv_sec;
<------>reply->tval_usec = ts.tv_nsec / 1000;
}
 
int drm_wait_vblank_ioctl(struct drm_device *dev, void *data,
<------><------><------>  struct drm_file *file_priv)
{
<------>struct drm_crtc *crtc;
<------>struct drm_vblank_crtc *vblank;
<------>union drm_wait_vblank *vblwait = data;
<------>int ret;
<------>u64 req_seq, seq;
<------>unsigned int pipe_index;
<------>unsigned int flags, pipe, high_pipe;
 
<------>if (!dev->irq_enabled)
<------><------>return -EOPNOTSUPP;
 
<------>if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
<------><------>return -EINVAL;
 
<------>if (vblwait->request.type &
<------>    ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
<------>      _DRM_VBLANK_HIGH_CRTC_MASK)) {
<------><------>drm_dbg_core(dev,
<------><------><------>     "Unsupported type value 0x%x, supported mask 0x%x\n",
<------><------><------>     vblwait->request.type,
<------><------><------>     (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK |
<------><------><------>      _DRM_VBLANK_HIGH_CRTC_MASK));
<------><------>return -EINVAL;
<------>}
 
<------>flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
<------>high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK);
<------>if (high_pipe)
<------><------>pipe_index = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT;
<------>else
<------><------>pipe_index = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
 
<------>/* Convert lease-relative crtc index into global crtc index */
<------>if (drm_core_check_feature(dev, DRIVER_MODESET)) {
<------><------>pipe = 0;
<------><------>drm_for_each_crtc(crtc, dev) {
<------><------><------>if (drm_lease_held(file_priv, crtc->base.id)) {
<------><------><------><------>if (pipe_index == 0)
<------><------><------><------><------>break;
<------><------><------><------>pipe_index--;
<------><------><------>}
<------><------><------>pipe++;
<------><------>}
<------>} else {
<------><------>pipe = pipe_index;
<------>}
 
<------>if (pipe >= dev->num_crtcs)
<------><------>return -EINVAL;
 
<------>vblank = &dev->vblank[pipe];
 
<------>/* If the counter is currently enabled and accurate, short-circuit
<------> * queries to return the cached timestamp of the last vblank.
<------> */
<------>if (dev->vblank_disable_immediate &&
<------>    drm_wait_vblank_is_query(vblwait) &&
<------>    READ_ONCE(vblank->enabled)) {
<------><------>drm_wait_vblank_reply(dev, pipe, &vblwait->reply);
<------><------>return 0;
<------>}
 
<------>ret = drm_vblank_get(dev, pipe);
<------>if (ret) {
<------><------>drm_dbg_core(dev,
<------><------><------>     "crtc %d failed to acquire vblank counter, %d\n",
<------><------><------>     pipe, ret);
<------><------>return ret;
<------>}
<------>seq = drm_vblank_count(dev, pipe);
 
<------>switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
<------>case _DRM_VBLANK_RELATIVE:
<------><------>req_seq = seq + vblwait->request.sequence;
<------><------>vblwait->request.sequence = req_seq;
<------><------>vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
<------><------>break;
<------>case _DRM_VBLANK_ABSOLUTE:
<------><------>req_seq = widen_32_to_64(vblwait->request.sequence, seq);
<------><------>break;
<------>default:
<------><------>ret = -EINVAL;
<------><------>goto done;
<------>}
 
<------>if ((flags & _DRM_VBLANK_NEXTONMISS) &&
<------>    drm_vblank_passed(seq, req_seq)) {
<------><------>req_seq = seq + 1;
<------><------>vblwait->request.type &= ~_DRM_VBLANK_NEXTONMISS;
<------><------>vblwait->request.sequence = req_seq;
<------>}
 
<------>if (flags & _DRM_VBLANK_EVENT) {
<------><------>/* must hold on to the vblank ref until the event fires
<------><------> * drm_vblank_put will be called asynchronously
<------><------> */
<------><------>return drm_queue_vblank_event(dev, pipe, req_seq, vblwait, file_priv);
<------>}
 
<------>if (req_seq != seq) {
<------><------>int wait;
 
<------><------>drm_dbg_core(dev, "waiting on vblank count %llu, crtc %u\n",
<------><------><------>     req_seq, pipe);
<------><------>wait = wait_event_interruptible_timeout(vblank->queue,
<------><------><------>drm_vblank_passed(drm_vblank_count(dev, pipe), req_seq) ||
<------><------><------><------>      !READ_ONCE(vblank->enabled),
<------><------><------>msecs_to_jiffies(3000));
 
<------><------>switch (wait) {
<------><------>case 0:
<------><------><------>/* timeout */
<------><------><------>ret = -EBUSY;
<------><------><------>break;
<------><------>case -ERESTARTSYS:
<------><------><------>/* interrupted by signal */
<------><------><------>ret = -EINTR;
<------><------><------>break;
<------><------>default:
<------><------><------>ret = 0;
<------><------><------>break;
<------><------>}
<------>}
 
<------>if (ret != -EINTR) {
<------><------>drm_wait_vblank_reply(dev, pipe, &vblwait->reply);
 
<------><------>drm_dbg_core(dev, "crtc %d returning %u to client\n",
<------><------><------>     pipe, vblwait->reply.sequence);
<------>} else {
<------><------>drm_dbg_core(dev, "crtc %d vblank wait interrupted by signal\n",
<------><------><------>     pipe);
<------>}
 
done:
<------>drm_vblank_put(dev, pipe);
<------>return ret;
}
 
static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
<------>bool high_prec = false;
<------>struct drm_pending_vblank_event *e, *t;
<------>ktime_t now;
<------>u64 seq;
 
<------>assert_spin_locked(&dev->event_lock);
 
<------>seq = drm_vblank_count_and_time(dev, pipe, &now);
 
<------>list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
<------><------>if (e->pipe != pipe)
<------><------><------>continue;
<------><------>if (!drm_vblank_passed(seq, e->sequence))
<------><------><------>continue;
 
<------><------>drm_dbg_core(dev, "vblank event on %llu, current %llu\n",
<------><------><------>     e->sequence, seq);
 
<------><------>list_del(&e->base.link);
<------><------>drm_vblank_put(dev, pipe);
<------><------>send_vblank_event(dev, e, seq, now);
<------>}
 
<------>if (crtc && crtc->funcs->get_vblank_timestamp)
<------><------>high_prec = true;
 
<------>trace_drm_vblank_event(pipe, seq, now, high_prec);
}
 
/**
 * drm_handle_vblank - handle a vblank event
 * @dev: DRM device
 * @pipe: index of CRTC where this event occurred
 *
 * Drivers should call this routine in their vblank interrupt handlers to
 * update the vblank counter and send any signals that may be pending.
 *
 * This is the legacy version of drm_crtc_handle_vblank().
 */
bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
{
<------>struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
<------>unsigned long irqflags;
<------>bool disable_irq;
 
<------>if (drm_WARN_ON_ONCE(dev, !drm_dev_has_vblank(dev)))
<------><------>return false;
 
<------>if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
<------><------>return false;
 
<------>spin_lock_irqsave(&dev->event_lock, irqflags);
 
<------>/* Need timestamp lock to prevent concurrent execution with
<------> * vblank enable/disable, as this would cause inconsistent
<------> * or corrupted timestamps and vblank counts.
<------> */
<------>spin_lock(&dev->vblank_time_lock);
 
<------>/* Vblank irq handling disabled. Nothing to do. */
<------>if (!vblank->enabled) {
<------><------>spin_unlock(&dev->vblank_time_lock);
<------><------>spin_unlock_irqrestore(&dev->event_lock, irqflags);
<------><------>return false;
<------>}
 
<------>drm_update_vblank_count(dev, pipe, true);
 
<------>spin_unlock(&dev->vblank_time_lock);
 
<------>wake_up(&vblank->queue);
 
<------>/* With instant-off, we defer disabling the interrupt until after
<------> * we finish processing the following vblank after all events have
<------> * been signaled. The disable has to be last (after
<------> * drm_handle_vblank_events) so that the timestamp is always accurate.
<------> */
<------>disable_irq = (dev->vblank_disable_immediate &&
<------><------>       drm_vblank_offdelay > 0 &&
<------><------>       !atomic_read(&vblank->refcount));
 
<------>drm_handle_vblank_events(dev, pipe);
<------>drm_handle_vblank_works(vblank);
 
<------>spin_unlock_irqrestore(&dev->event_lock, irqflags);
 
<------>if (disable_irq)
<------><------>vblank_disable_fn(&vblank->disable_timer);
 
<------>return true;
}
EXPORT_SYMBOL(drm_handle_vblank);
 
/**
 * drm_crtc_handle_vblank - handle a vblank event
 * @crtc: where this event occurred
 *
 * Drivers should call this routine in their vblank interrupt handlers to
 * update the vblank counter and send any signals that may be pending.
 *
 * This is the native KMS version of drm_handle_vblank().
 *
 * Note that for a given vblank counter value drm_crtc_handle_vblank()
 * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time()
 * provide a barrier: Any writes done before calling
 * drm_crtc_handle_vblank() will be visible to callers of the later
 * functions, iff the vblank count is the same or a later one.
 *
 * See also &drm_vblank_crtc.count.
 *
 * Returns:
 * True if the event was successfully handled, false on failure.
 */
bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
{
<------>return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_handle_vblank);
 
/*
 * Get crtc VBLANK count.
 *
 * \param dev DRM device
 * \param data user arguement, pointing to a drm_crtc_get_sequence structure.
 * \param file_priv drm file private for the user's open file descriptor
 */
 
int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data,
<------><------><------><------>struct drm_file *file_priv)
{
<------>struct drm_crtc *crtc;
<------>struct drm_vblank_crtc *vblank;
<------>int pipe;
<------>struct drm_crtc_get_sequence *get_seq = data;
<------>ktime_t now;
<------>bool vblank_enabled;
<------>int ret;
 
<------>if (!drm_core_check_feature(dev, DRIVER_MODESET))
<------><------>return -EOPNOTSUPP;
 
<------>if (!dev->irq_enabled)
<------><------>return -EOPNOTSUPP;
 
<------>crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id);
<------>if (!crtc)
<------><------>return -ENOENT;
 
<------>pipe = drm_crtc_index(crtc);
 
<------>vblank = &dev->vblank[pipe];
<------>vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled);
 
<------>if (!vblank_enabled) {
<------><------>ret = drm_crtc_vblank_get(crtc);
<------><------>if (ret) {
<------><------><------>drm_dbg_core(dev,
<------><------><------><------>     "crtc %d failed to acquire vblank counter, %d\n",
<------><------><------><------>     pipe, ret);
<------><------><------>return ret;
<------><------>}
<------>}
<------>drm_modeset_lock(&crtc->mutex, NULL);
<------>if (crtc->state)
<------><------>get_seq->active = crtc->state->enable;
<------>else
<------><------>get_seq->active = crtc->enabled;
<------>drm_modeset_unlock(&crtc->mutex);
<------>get_seq->sequence = drm_vblank_count_and_time(dev, pipe, &now);
<------>get_seq->sequence_ns = ktime_to_ns(now);
<------>if (!vblank_enabled)
<------><------>drm_crtc_vblank_put(crtc);
<------>return 0;
}
 
/*
 * Queue a event for VBLANK sequence
 *
 * \param dev DRM device
 * \param data user arguement, pointing to a drm_crtc_queue_sequence structure.
 * \param file_priv drm file private for the user's open file descriptor
 */
 
int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data,
<------><------><------><------>  struct drm_file *file_priv)
{
<------>struct drm_crtc *crtc;
<------>struct drm_vblank_crtc *vblank;
<------>int pipe;
<------>struct drm_crtc_queue_sequence *queue_seq = data;
<------>ktime_t now;
<------>struct drm_pending_vblank_event *e;
<------>u32 flags;
<------>u64 seq;
<------>u64 req_seq;
<------>int ret;
 
<------>if (!drm_core_check_feature(dev, DRIVER_MODESET))
<------><------>return -EOPNOTSUPP;
 
<------>if (!dev->irq_enabled)
<------><------>return -EOPNOTSUPP;
 
<------>crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id);
<------>if (!crtc)
<------><------>return -ENOENT;
 
<------>flags = queue_seq->flags;
<------>/* Check valid flag bits */
<------>if (flags & ~(DRM_CRTC_SEQUENCE_RELATIVE|
<------><------>      DRM_CRTC_SEQUENCE_NEXT_ON_MISS))
<------><------>return -EINVAL;
 
<------>pipe = drm_crtc_index(crtc);
 
<------>vblank = &dev->vblank[pipe];
 
<------>e = kzalloc(sizeof(*e), GFP_KERNEL);
<------>if (e == NULL)
<------><------>return -ENOMEM;
 
<------>ret = drm_crtc_vblank_get(crtc);
<------>if (ret) {
<------><------>drm_dbg_core(dev,
<------><------><------>     "crtc %d failed to acquire vblank counter, %d\n",
<------><------><------>     pipe, ret);
<------><------>goto err_free;
<------>}
 
<------>seq = drm_vblank_count_and_time(dev, pipe, &now);
<------>req_seq = queue_seq->sequence;
 
<------>if (flags & DRM_CRTC_SEQUENCE_RELATIVE)
<------><------>req_seq += seq;
 
<------>if ((flags & DRM_CRTC_SEQUENCE_NEXT_ON_MISS) && drm_vblank_passed(seq, req_seq))
<------><------>req_seq = seq + 1;
 
<------>e->pipe = pipe;
<------>e->event.base.type = DRM_EVENT_CRTC_SEQUENCE;
<------>e->event.base.length = sizeof(e->event.seq);
<------>e->event.seq.user_data = queue_seq->user_data;
 
<------>spin_lock_irq(&dev->event_lock);
 
<------>/*
<------> * drm_crtc_vblank_off() might have been called after we called
<------> * drm_crtc_vblank_get(). drm_crtc_vblank_off() holds event_lock around the
<------> * vblank disable, so no need for further locking.  The reference from
<------> * drm_crtc_vblank_get() protects against vblank disable from another source.
<------> */
<------>if (!READ_ONCE(vblank->enabled)) {
<------><------>ret = -EINVAL;
<------><------>goto err_unlock;
<------>}
 
<------>ret = drm_event_reserve_init_locked(dev, file_priv, &e->base,
<------><------><------><------><------>    &e->event.base);
 
<------>if (ret)
<------><------>goto err_unlock;
 
<------>e->sequence = req_seq;
 
<------>if (drm_vblank_passed(seq, req_seq)) {
<------><------>drm_crtc_vblank_put(crtc);
<------><------>send_vblank_event(dev, e, seq, now);
<------><------>queue_seq->sequence = seq;
<------>} else {
<------><------>/* drm_handle_vblank_events will call drm_vblank_put */
<------><------>list_add_tail(&e->base.link, &dev->vblank_event_list);
<------><------>queue_seq->sequence = req_seq;
<------>}
 
<------>spin_unlock_irq(&dev->event_lock);
<------>return 0;
 
err_unlock:
<------>spin_unlock_irq(&dev->event_lock);
<------>drm_crtc_vblank_put(crtc);
err_free:
<------>kfree(e);
<------>return ret;
}