diff options
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 1623 |
1 files changed, 22 insertions, 1601 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index c7debaad67f8..28d736c3fcb4 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -3,6 +3,25 @@ * * \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. */ /* @@ -32,429 +51,15 @@ * OTHER DEALINGS IN THE SOFTWARE. */ +#include <drm/drm_irq.h> #include <drm/drmP.h> -#include "drm_trace.h" -#include "drm_internal.h" #include <linux/interrupt.h> /* For task queue support */ -#include <linux/slab.h> #include <linux/vgaarb.h> #include <linux/export.h> -/* 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, - struct timeval *tvblank, bool in_vblank_irq); - -static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */ - -/* - * Default to use monotonic timestamps for wait-for-vblank and page-flip - * complete events. - */ -unsigned int drm_timestamp_monotonic = 1; - -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_param_named(timestamp_monotonic, drm_timestamp_monotonic, 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]"); -MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps"); - -static void store_vblank(struct drm_device *dev, unsigned int pipe, - u32 vblank_count_inc, - struct timeval *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; - vblank->count += vblank_count_inc; - write_sequnlock(&vblank->seqlock); -} - -/* - * "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) -{ - WARN_ON_ONCE(dev->max_vblank_count != 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 (crtc->funcs->get_vblank_counter) - return crtc->funcs->get_vblank_counter(crtc); - } - - 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; - struct timeval 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 = (struct timeval) {0, 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; - struct timeval t_vblank; - int count = DRM_TIMESTAMP_MAXRETRIES; - int framedur_ns = vblank->framedur_ns; - - /* - * 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 (dev->max_vblank_count != 0) { - /* trust the hw counter when it's around */ - diff = (cur_vblank - vblank->last) & dev->max_vblank_count; - } else if (rc && framedur_ns) { - const struct timeval *t_old; - u64 diff_ns; - - t_old = &vblank->time; - diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old); - - /* - * Figure out how many vblanks we've missed based - * on the difference in the timestamps and the - * frame/field duration. - */ - diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); - - if (diff == 0 && in_vblank_irq) - DRM_DEBUG_VBL("crtc %u: Redundant vblirq ignored." - " diff_ns = %lld, framedur_ns = %d)\n", - pipe, (long long) diff_ns, framedur_ns); - } 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_DEBUG_VBL("clamping vblank bump to 1 on crtc %u: diffr=%u" - " due to pre-modeset.\n", pipe, diff); - diff = 1; - } - - DRM_DEBUG_VBL("updating vblank count on crtc %u:" - " current=%u, diff=%u, hw=%u hw_last=%u\n", - pipe, vblank->count, diff, cur_vblank, vblank->last); - - if (diff == 0) { - WARN_ON_ONCE(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 = (struct timeval) {0, 0}; - - store_vblank(dev, pipe, diff, &t_vblank, cur_vblank); -} - -static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return 0; - - return vblank->count; -} - -/** - * drm_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 irq's. - * - * This is mostly useful for hardware that can obtain the scanout - * position, but doesn't have a frame counter. - */ -u32 drm_accurate_vblank_count(struct drm_crtc *crtc) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - u32 vblank; - unsigned long flags; - - WARN(!dev->driver->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_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 (crtc->funcs->disable_vblank) { - crtc->funcs->disable_vblank(crtc); - return; - } - } - - 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. - */ -static void 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); - - /* - * Only disable vblank interrupts if they're enabled. This avoids - * calling the ->disable_vblank() operation in atomic context with the - * hardware potentially runtime suspended. - */ - if (vblank->enabled) { - __disable_vblank(dev, pipe); - vblank->enabled = false; - } - - /* - * Always 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); - - spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); -} - -static void vblank_disable_fn(unsigned long arg) -{ - struct drm_vblank_crtc *vblank = (void *)arg; - 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_DEBUG("disabling vblank on crtc %u\n", pipe); - vblank_disable_and_save(dev, pipe); - } - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); -} - -/** - * drm_vblank_cleanup - cleanup vblank support - * @dev: DRM device - * - * This function cleans up any resources allocated in drm_vblank_init. - */ -void drm_vblank_cleanup(struct drm_device *dev) -{ - unsigned int pipe; - - /* Bail if the driver didn't call drm_vblank_init() */ - if (dev->num_crtcs == 0) - return; - - for (pipe = 0; pipe < dev->num_crtcs; pipe++) { - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - WARN_ON(READ_ONCE(vblank->enabled) && - drm_core_check_feature(dev, DRIVER_MODESET)); - - del_timer_sync(&vblank->disable_timer); - } - - kfree(dev->vblank); - - dev->num_crtcs = 0; -} -EXPORT_SYMBOL(drm_vblank_cleanup); - -/** - * 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. - * - * 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 = -ENOMEM; - unsigned int i; - - spin_lock_init(&dev->vbl_lock); - spin_lock_init(&dev->vblank_time_lock); - - dev->num_crtcs = num_crtcs; - - dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL); - if (!dev->vblank) - goto err; - - 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); - setup_timer(&vblank->disable_timer, vblank_disable_fn, - (unsigned long)vblank); - seqlock_init(&vblank->seqlock); - } - - DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); - - /* Driver specific high-precision vblank timestamping supported? */ - if (dev->driver->get_vblank_timestamp) - DRM_INFO("Driver supports precise vblank timestamp query.\n"); - else - DRM_INFO("No driver support for vblank timestamp query.\n"); - - /* Must have precise timestamping for reliable vblank instant disable */ - if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { - dev->vblank_disable_immediate = false; - DRM_INFO("Setting vblank_disable_immediate to false because " - "get_vblank_timestamp == NULL\n"); - } - - return 0; - -err: - dev->num_crtcs = 0; - return ret; -} -EXPORT_SYMBOL(drm_vblank_init); +#include "drm_internal.h" /** * drm_irq_install - install IRQ handler @@ -571,7 +176,7 @@ int drm_irq_uninstall(struct drm_device *dev) WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET)); - vblank_disable_and_save(dev, i); + drm_vblank_disable_and_save(dev, i); wake_up(&vblank->queue); } spin_unlock_irqrestore(&dev->vbl_lock, irqflags); @@ -634,1187 +239,3 @@ int drm_legacy_irq_control(struct drm_device *dev, void *data, return -EINVAL; } } - -/** - * 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_calc_vbltimestamp_from_scanoutpos(). 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 (!dev->num_crtcs) - return; - - if (WARN_ON(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_ERROR("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_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n", - crtc->base.id, mode->crtc_htotal, - mode->crtc_vtotal, mode->crtc_vdisplay); - DRM_DEBUG("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_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper - * @dev: DRM device - * @pipe: index of 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 struct timeval 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 called from - * within get_vblank_timestamp() implementation of a kms driver to implement the - * actual timestamping. - * - * Should return timestamps conforming to the OML_sync_control OpenML - * extension specification. The timestamp corresponds to the end of - * the vblank interval, aka start of scanout of topmost-leftmost display - * pixel in the following video frame. - * - * Requires support for optional dev->driver->get_scanout_position() - * in kms driver, plus a bit of setup code to provide a drm_display_mode - * that corresponds to the true scanout timing. - * - * The current implementation only handles standard video modes. It - * returns as no operation if a doublescan or interlaced video mode is - * active. Higher level code is expected to handle this. - * - * This function can be used to implement the &drm_driver.get_vblank_timestamp - * directly, if the driver implements the &drm_driver.get_scanout_position hook. - * - * 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_update_legacy_modeset_state(). - * - * Returns: - * - * Returns true on success, and false on failure, i.e. when no accurate - * timestamp could be acquired. - */ -bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, - unsigned int pipe, - int *max_error, - struct timeval *vblank_time, - bool in_vblank_irq) -{ - struct timeval tv_etime; - ktime_t stime, etime; - bool vbl_status; - struct drm_crtc *crtc; - const struct drm_display_mode *mode; - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - int vpos, hpos, i; - int delta_ns, duration_ns; - - if (!drm_core_check_feature(dev, DRIVER_MODESET)) - return false; - - crtc = drm_crtc_from_index(dev, pipe); - - if (pipe >= dev->num_crtcs || !crtc) { - DRM_ERROR("Invalid crtc %u\n", pipe); - return false; - } - - /* Scanout position query not supported? Should not happen. */ - if (!dev->driver->get_scanout_position) { - DRM_ERROR("Called from driver 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_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe); - WARN_ON_ONCE(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 = dev->driver->get_scanout_position(dev, pipe, - in_vblank_irq, - &vpos, &hpos, - &stime, &etime, - mode); - - /* Return as no-op if scanout query unsupported or failed. */ - if (!vbl_status) { - DRM_DEBUG("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_DEBUG("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); - - if (!drm_timestamp_monotonic) - etime = ktime_mono_to_real(etime); - - /* save this only for debugging purposes */ - tv_etime = ktime_to_timeval(etime); - /* Subtract time delta from raw timestamp to get final - * vblank_time timestamp for end of vblank. - */ - etime = ktime_sub_ns(etime, delta_ns); - *vblank_time = ktime_to_timeval(etime); - - DRM_DEBUG_VBL("crtc %u : v p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", - pipe, hpos, vpos, - (long)tv_etime.tv_sec, (long)tv_etime.tv_usec, - (long)vblank_time->tv_sec, (long)vblank_time->tv_usec, - duration_ns/1000, i); - - return true; -} -EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); - -static struct timeval get_drm_timestamp(void) -{ - ktime_t now; - - now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real(); - return ktime_to_timeval(now); -} - -/** - * 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 struct timeval 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, - struct timeval *tvblank, bool in_vblank_irq) -{ - 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 (dev->driver->get_vblank_timestamp && (max_error > 0)) - ret = dev->driver->get_vblank_timestamp(dev, pipe, &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 = get_drm_timestamp(); - - 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. - * - * Returns: - * The software vblank counter. - */ -u32 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 struct timeval 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 u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, - struct timeval *vblanktime) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - u32 vblank_count; - unsigned int seq; - - if (WARN_ON(pipe >= dev->num_crtcs)) { - *vblanktime = (struct timeval) { 0 }; - return 0; - } - - do { - seq = read_seqbegin(&vblank->seqlock); - vblank_count = 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 struct timeval 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. - */ -u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, - struct timeval *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, - unsigned long seq, struct timeval *now) -{ - e->event.sequence = seq; - e->event.tv_sec = now->tv_sec; - e->event.tv_usec = now->tv_usec; - - trace_drm_vblank_event_delivered(e->base.file_priv, e->pipe, - e->event.sequence); - - drm_send_event_locked(dev, &e->base); -} - -/** - * 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 again 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 event lock. Caller must also hold a vblank reference for - * the event @e, 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->event.sequence = drm_vblank_count(dev, pipe); - e->event.crtc_id = crtc->base.id; - 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; - unsigned int seq, pipe = drm_crtc_index(crtc); - struct timeval now; - - if (dev->num_crtcs > 0) { - seq = drm_vblank_count_and_time(dev, pipe, &now); - } else { - seq = 0; - - now = get_drm_timestamp(); - } - e->pipe = pipe; - e->event.crtc_id = crtc->base.id; - 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 (crtc->funcs->enable_vblank) - return crtc->funcs->enable_vblank(crtc); - } - - return dev->driver->enable_vblank(dev, pipe); -} - -/** - * drm_vblank_enable - enable the vblank interrupt on a CRTC - * @dev: DRM device - * @pipe: CRTC index - * - * Returns: - * Zero on success or a negative error code on failure. - */ -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_DEBUG("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; -} - -/** - * drm_vblank_get - get a reference count on vblank events - * @dev: DRM device - * @pipe: index of CRTC to own - * - * Acquire a reference count on vblank events to avoid having them disabled - * while in use. - * - * This is the legacy version of drm_crtc_vblank_get(). - * - * Returns: - * Zero on success or a negative error code on failure. - */ -static 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 (!dev->num_crtcs) - return -EINVAL; - - if (WARN_ON(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); - -/** - * drm_vblank_put - release ownership of vblank events - * @dev: DRM device - * @pipe: index of CRTC to release - * - * Release ownership of a given vblank counter, turning off interrupts - * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. - * - * This is the legacy version of drm_crtc_vblank_put(). - */ -static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - if (WARN_ON(atomic_read(&vblank->refcount) == 0)) - return; - - /* Last user schedules interrupt disable */ - if (atomic_dec_and_test(&vblank->refcount)) { - if (drm_vblank_offdelay == 0) - return; |