| /* |
| * drm_irq.c IRQ and vblank support |
| * |
| * \author Rickard E. (Rik) Faith <faith@valinux.com> |
| * \author Gareth Hughes <gareth@valinux.com> |
| */ |
| |
| /* |
| * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com |
| * |
| * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. |
| * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. |
| * All Rights Reserved. |
| * |
| * 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 <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); |
| |
| /** |
| * drm_irq_install - install IRQ handler |
| * @dev: DRM device |
| * @irq: IRQ number to install the handler for |
| * |
| * Initializes the IRQ related data. Installs the handler, calling the driver |
| * irq_preinstall() and irq_postinstall() functions before and after the |
| * installation. |
| * |
| * This is the simplified helper interface provided for drivers with no special |
| * needs. Drivers which need to install interrupt handlers for multiple |
| * interrupts must instead set &drm_device.irq_enabled to signal the DRM core |
| * that vblank interrupts are available. |
| * |
| * Returns: |
| * Zero on success or a negative error code on failure. |
| */ |
| int drm_irq_install(struct drm_device *dev, int irq) |
| { |
| int ret; |
| unsigned long sh_flags = 0; |
| |
| if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) |
| return -EINVAL; |
| |
| if (irq == 0) |
| return -EINVAL; |
| |
| /* Driver must have been initialized */ |
| if (!dev->dev_private) |
| return -EINVAL; |
| |
| if (dev->irq_enabled) |
| return -EBUSY; |
| dev->irq_enabled = true; |
| |
| DRM_DEBUG("irq=%d\n", irq); |
| |
| /* Before installing handler */ |
| if (dev->driver->irq_preinstall) |
| dev->driver->irq_preinstall(dev); |
| |
| /* Install handler */ |
| if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED)) |
| sh_flags = IRQF_SHARED; |
| |
| ret = request_irq(irq, dev->driver->irq_handler, |
| sh_flags, dev->driver->name, dev); |
| |
| if (ret < 0) { |
| dev->irq_enabled = false; |
| return ret; |
| } |
| |
| /* After installing handler */ |
| if (dev->driver->irq_postinstall) |
| ret = dev->driver->irq_postinstall(dev); |
| |
| if (ret < 0) { |
| dev->irq_enabled = false; |
| if (drm_core_check_feature(dev, DRIVER_LEGACY)) |
| vga_client_register(dev->pdev, NULL, NULL, NULL); |
| free_irq(irq, dev); |
| } else { |
| dev->irq = irq; |
| } |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(drm_irq_install); |
| |
| /** |
| * drm_irq_uninstall - uninstall the IRQ handler |
| * @dev: DRM device |
| * |
| * Calls the driver's irq_uninstall() function and unregisters the IRQ handler. |
| * This should only be called by drivers which used drm_irq_install() to set up |
| * their interrupt handler. Other drivers must only reset |
| * &drm_device.irq_enabled to false. |
| * |
| * Note that for kernel modesetting drivers it is a bug if this function fails. |
| * The sanity checks are only to catch buggy user modesetting drivers which call |
| * the same function through an ioctl. |
| * |
| * Returns: |
| * Zero on success or a negative error code on failure. |
| */ |
| int drm_irq_uninstall(struct drm_device *dev) |
| { |
| unsigned long irqflags; |
| bool irq_enabled; |
| int i; |
| |
| if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) |
| return -EINVAL; |
| |
| irq_enabled = dev->irq_enabled; |
| dev->irq_enabled = false; |
| |
| /* |
| * Wake up any waiters so they don't hang. This is just to paper over |
| * issues for UMS drivers which aren't in full control of their |
| * vblank/irq handling. KMS drivers must ensure that vblanks are all |
| * disabled when uninstalling the irq handler. |
| */ |
| if (dev->num_crtcs) { |
| spin_lock_irqsave(&dev->vbl_lock, irqflags); |
| for (i = 0; i < dev->num_crtcs; i++) { |
| struct drm_vblank_crtc *vblank = &dev->vblank[i]; |
| |
| if (!vblank->enabled) |
| continue; |
| |
| WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET)); |
| |
| vblank_disable_and_save(dev, i); |
| wake_up(&vblank->queue); |
| } |
| spin_unlock_irqrestore(&dev->vbl_lock, irqflags); |
| } |
| |
| if (!irq_enabled) |
| return -EINVAL; |
| |
| DRM_DEBUG("irq=%d\n", dev->irq); |
| |
| if (drm_core_check_feature(dev, DRIVER_LEGACY)) |
| vga_client_register(dev->pdev, NULL, NULL, NULL); |
| |
| if (dev->driver->irq_uninstall) |
| dev->driver->irq_uninstall(dev); |
| |
| free_irq(dev->irq, dev); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(drm_irq_uninstall); |
| |
| int drm_legacy_irq_control(struct drm_device *dev, void *data, |
| struct drm_file *file_priv) |
| { |
| struct drm_control *ctl = data; |
| int ret = 0, irq; |
| |
| /* if we haven't irq we fallback for compatibility reasons - |
| * this used to be a separate function in drm_dma.h |
| */ |
| |
| if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) |
| return 0; |
| if (!drm_core_check_feature(dev, DRIVER_LEGACY)) |
| return 0; |
| /* UMS was only ever supported on pci devices. */ |
| if (WARN_ON(!dev->pdev)) |
| return -EINVAL; |
| |
| switch (ctl->func) { |
| case DRM_INST_HANDLER: |
| irq = dev->pdev->irq; |
| |
| if (dev->if_version < DRM_IF_VERSION(1, 2) && |
| ctl->irq != irq) |
| return -EINVAL; |
| mutex_lock(&dev->struct_mutex); |
| ret = drm_irq_install(dev, irq); |
| mutex_unlock(&dev->struct_mutex); |
| |
| return ret; |
| case DRM_UNINST_HANDLER: |
| mutex_lock(&dev->struct_mutex); |
| ret = drm_irq_uninstall(dev); |
| mutex_unlock(&dev->struct_mutex); |
| |
| return ret; |
| default: |
| 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; |
| else if (drm_vblank_offdelay < 0) |
| vblank_disable_fn((unsigned long)vblank); |
| 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. |
| */ |
| void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe) |
| { |
| struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
| int ret; |
| u32 last; |
| |
| if (WARN_ON(pipe >= dev->num_crtcs)) |
| return; |
| |
| ret = drm_vblank_get(dev, pipe); |
| if (WARN(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)); |
| |
| WARN(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. |
| */ |
| 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; |
| struct timeval now; |
| unsigned long irqflags; |
| unsigned int seq; |
| |
| if (WARN_ON(pipe >= dev->num_crtcs)) |
| return; |
| |
| spin_lock_irqsave(&dev->event_lock, irqflags); |
| |
| spin_lock(&dev->vbl_lock); |
| DRM_DEBUG_VBL("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) |
| 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_DEBUG("Sending premature vblank event on disable: " |
| "wanted %u, current %u\n", |
| e->event.sequence, seq); |
| list_del(&e->base.link); |
| drm_vblank_put(dev, pipe); |
| send_vblank_event(dev, e, seq, &now); |
| } |
| spin_unlock_irqrestore(&dev->event_lock, irqflags); |
| |
| /* Will be reset by the modeset helpers when re-enabling the crtc by |
| * calling drm_calc_timestamping_constants(). */ |
| vblank->hwmode.crtc_clock = 0; |
| } |
| 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. |
| */ |
| void drm_crtc_vblank_reset(struct drm_crtc *crtc) |
| { |
| struct drm_device *dev = crtc->dev; |
| unsigned long irqflags; |
| unsigned int pipe = drm_crtc_index(crtc); |
| struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
| |
| spin_lock_irqsave(&dev->vbl_lock, irqflags); |
| /* |
| * 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_irqrestore(&dev->vbl_lock, irqflags); |
| |
| WARN_ON(!list_empty(&dev->vblank_event_list)); |
| } |
| EXPORT_SYMBOL(drm_crtc_vblank_reset); |
| |
| /** |
| * 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. 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]; |
| unsigned long irqflags; |
| |
| if (WARN_ON(pipe >= dev->num_crtcs)) |
| return; |
| |
| spin_lock_irqsave(&dev->vbl_lock, irqflags); |
| DRM_DEBUG_VBL("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) |
| WARN_ON(drm_vblank_enable(dev, pipe)); |
| spin_unlock_irqrestore(&dev->vbl_lock, irqflags); |
| } |
| EXPORT_SYMBOL(drm_crtc_vblank_on); |
| |
| 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 (!dev->num_crtcs) |
| return; |
| |
| if (WARN_ON(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]; |
| unsigned long irqflags; |
| |
| /* vblank is not initialized (IRQ not installed ?), or has been freed */ |
| if (!dev->num_crtcs) |
| return; |
| |
| if (WARN_ON(pipe >= dev->num_crtcs)) |
| return; |
| |
| if (vblank->inmodeset) { |
| spin_lock_irqsave(&dev->vbl_lock, irqflags); |
| drm_reset_vblank_timestamp(dev, pipe); |
| spin_unlock_irqrestore(&dev->vbl_lock, irqflags); |
| |
| if (vblank->inmodeset & 0x2) |
| drm_vblank_put(dev, pipe); |
| |
| vblank->inmodeset = 0; |
| } |
| } |
| |
| int drm_legacy_modeset_ctl(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 (!dev->num_crtcs) |
| 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 inline bool vblank_passed(u32 seq, u32 ref) |
| { |
| return (seq - ref) <= (1 << 23); |
| } |
| |
| static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, |
| union drm_wait_vblank *vblwait, |
| struct drm_file *file_priv) |
| { |
| struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; |
| struct drm_pending_vblank_event *e; |
| struct timeval now; |
| unsigned long flags; |
| unsigned int 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); |
| e->event.user_data = vblwait->request.signal; |
| |
| spin_lock_irqsave(&dev->event_lock, flags); |
| |
| /* |
| * 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_DEBUG("event on vblank count %u, current %u, crtc %u\n", |
| vblwait->request.sequence, seq, pipe); |
| |
| trace_drm_vblank_event_queued(file_priv, pipe, |
| vblwait->request.sequence); |
| |
| e->event.sequence = vblwait->request.sequence; |
| if (vblank_passed(seq, vblwait->request.sequence)) { |
| 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 = vblwait->request.sequence; |
| } |
| |
| spin_unlock_irqrestore(&dev->event_lock, flags); |
| |
| return 0; |
| |
| err_unlock: |
| spin_unlock_irqrestore(&dev->event_lock, flags); |
| 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)); |
| } |
| |
| /* |
| * Wait for VBLANK. |
| * |
| * \param inode device inode. |
| * \param file_priv DRM file private. |
| * \param cmd command. |
| * \param data user argument, pointing to a drm_wait_vblank structure. |
| * \return zero on success or a negative number on failure. |
| * |
| * This function enables the vblank interrupt on the pipe requested, then |
| * sleeps waiting for the requested sequence number to occur, and drops |
| * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that |
| * after a timeout with no further vblank waits scheduled). |
| */ |
| int drm_wait_vblank(struct drm_device *dev, void *data, |
| struct drm_file *file_priv) |
| { |
| struct drm_vblank_crtc *vblank; |
| union drm_wait_vblank *vblwait = data; |
| int ret; |
| unsigned int flags, seq, pipe, high_pipe; |
| |
| if (!dev->irq_enabled) |
| return -EINVAL; |
| |
| 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_ERROR("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 = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT; |
| else |
| pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; |
| 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)) { |
| struct timeval now; |
| |
| vblwait->reply.sequence = |
| drm_vblank_count_and_time(dev, pipe, &now); |
| vblwait->reply.tval_sec = now.tv_sec; |
| vblwait->reply.tval_usec = now.tv_usec; |
| return 0; |
| } |
| |
| ret = drm_vblank_get(dev, pipe); |
| if (ret) { |
| DRM_DEBUG("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: |
| vblwait->request.sequence += seq; |
| vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; |
| case _DRM_VBLANK_ABSOLUTE: |
| break; |
| default: |
| ret = -EINVAL; |
| goto done; |
| } |
| |
| if ((flags & _DRM_VBLANK_NEXTONMISS) && |
| vblank_passed(seq, vblwait->request.sequence)) |
| vblwait->request.sequence = seq + 1; |
| |
| 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, vblwait, file_priv); |
| } |
| |
| if (vblwait->request.sequence != seq) { |
| DRM_DEBUG("waiting on vblank count %u, crtc %u\n", |
| vblwait->request.sequence, pipe); |
| DRM_WAIT_ON(ret, vblank->queue, 3 * HZ, |
| vblank_passed(drm_vblank_count(dev, pipe), |
| vblwait->request.sequence) || |
| !READ_ONCE(vblank->enabled)); |
| } |
| |
| if (ret != -EINTR) { |
| struct timeval now; |
| |
| vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now); |
| vblwait->reply.tval_sec = now.tv_sec; |
| vblwait->reply.tval_usec = now.tv_usec; |
| |
| DRM_DEBUG("crtc %d returning %u to client\n", |
| pipe, vblwait->reply.sequence); |
| } else { |
| DRM_DEBUG("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_pending_vblank_event *e, *t; |
| struct timeval now; |
| unsigned int 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 (!vblank_passed(seq, e->event.sequence)) |
| continue; |
| |
| DRM_DEBUG("vblank event on %u, current %u\n", |
| e->event.sequence, seq); |
| |
| list_del(&e->base.link); |
| drm_vblank_put(dev, pipe); |
| send_vblank_event(dev, e, seq, &now); |
| } |
| |
| trace_drm_vblank_event(pipe, seq); |
| } |
| |
| /** |
| * 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 (WARN_ON_ONCE(!dev->num_crtcs)) |
| return false; |
| |
| if (WARN_ON(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); |
| |
| spin_unlock_irqrestore(&dev->event_lock, irqflags); |
| |
| if (disable_irq) |
| vblank_disable_fn((unsigned long)vblank); |
| |
| 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(). |
| * |
| * 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); |