| /* |
| * 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| * For historical reference, the vertical blanking period was designed to |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 |
| * | | ("scan 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); |
| } |
| #ifdef CONFIG_DRM_LEGACY |
| else if (dev->driver->get_vblank_counter) { |
| return dev->driver->get_vblank_counter(dev, pipe); |
| } |
| #endif |
| |
| 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); |
| } |
| #ifdef CONFIG_DRM_LEGACY |
| else { |
| dev->driver->disable_vblank(dev, pipe); |
| } |
| #endif |
| } |
| |
| /* |
| * 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); |
| } |
| #ifdef CONFIG_DRM_LEGACY |
| else if (dev->driver->enable_vblank) { |
| return dev->driver->enable_vblank(dev, pipe); |
| } |
| #endif |
| |
| 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; |
| } |
| |