/* * drm_irq.c IRQ and vblank support * * \author Rickard E. (Rik) Faith * \author Gareth Hughes */ /* * 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 #include //#include "drm_trace.h" //#include /* For task queue support */ #include //#include #include /* Access macro for slots in vblank timestamp ringbuffer. */ #define vblanktimestamp(dev, crtc, count) \ ((dev)->vblank[crtc].time[(count) % DRM_VBLANKTIME_RBSIZE]) /* 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 /* * Clear vblank timestamp buffer for a crtc. */ #if 0 /** * 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, int num_crtcs) { int i, ret = -ENOMEM; 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++) { dev->vblank[i].dev = dev; dev->vblank[i].crtc = i; init_waitqueue_head(&dev->vblank[i].queue); setup_timer(&dev->vblank[i].disable_timer, vblank_disable_fn, (unsigned long)&dev->vblank[i]); } 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"); dev->vblank_disable_allowed = false; return 0; err: drm_vblank_cleanup(dev); return ret; } EXPORT_SYMBOL(drm_vblank_init); #endif irqreturn_t device_irq_handler(struct drm_device *dev) { // printf("video irq\n"); // printf("device %p driver %p handler %p\n", dev, dev->driver, dev->driver->irq_handler) ; return dev->driver->irq_handler(0, dev); } /** * 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); ret = !AttachIntHandler(irq, device_irq_handler, (u32)dev); /* After installing handler */ if (dev->driver->irq_postinstall) ret = dev->driver->irq_postinstall(dev); if (ret < 0) { dev->irq_enabled = false; DRM_ERROR(__FUNCTION__); } else { dev->irq = irq; } u16_t cmd = PciRead16(dev->pdev->busnr, dev->pdev->devfn, 4); cmd&= ~(1<<10); PciWrite16(dev->pdev->busnr, dev->pdev->devfn, 4, cmd); return ret; } EXPORT_SYMBOL(drm_irq_install); u64 div64_u64(u64 dividend, u64 divisor) { u32 high, d; high = divisor >> 32; if (high) { unsigned int shift = fls(high); d = divisor >> shift; dividend >>= shift; } else d = divisor; return div_u64(dividend, d); } /** * 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) { int linedur_ns = 0, pixeldur_ns = 0, framedur_ns = 0; int dotclock = mode->crtc_clock; /* 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, frame duration * and pixel duration in nanoseconds: */ pixeldur_ns = 1000000 / dotclock; 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 %d: Can't calculate constants, dotclock = 0!\n", crtc->base.id); crtc->pixeldur_ns = pixeldur_ns; crtc->linedur_ns = linedur_ns; crtc->framedur_ns = framedur_ns; DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n", crtc->base.id, mode->crtc_htotal, mode->crtc_vtotal, mode->crtc_vdisplay); DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n", crtc->base.id, dotclock, framedur_ns, linedur_ns, pixeldur_ns); } EXPORT_SYMBOL(drm_calc_timestamping_constants); /** * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper * @dev: DRM device * @crtc: Which CRTC's 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 * @flags: Flags to pass to driver: * 0 = Default, * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler * @refcrtc: CRTC which defines scanout timing * @mode: mode which defines the scanout timings * * 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. * * Returns: * Negative value on error, failure or if not supported in current * video mode: * * -EINVAL - Invalid CRTC. * -EAGAIN - Temporary unavailable, e.g., called before initial modeset. * -ENOTSUPP - Function not supported in current display mode. * -EIO - Failed, e.g., due to failed scanout position query. * * Returns or'ed positive status flags on success: * * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping. * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval. * */ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, int *max_error, struct timeval *vblank_time, unsigned flags, const struct drm_crtc *refcrtc, const struct drm_display_mode *mode) { struct timeval tv_etime; int vbl_status; int vpos, hpos, i; int framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns; bool invbl; if (crtc < 0 || crtc >= dev->num_crtcs) { DRM_ERROR("Invalid crtc %d\n", crtc); return -EINVAL; } /* 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 -EIO; } /* Durations of frames, lines, pixels in nanoseconds. */ framedur_ns = refcrtc->framedur_ns; linedur_ns = refcrtc->linedur_ns; pixeldur_ns = refcrtc->pixeldur_ns; /* If mode timing undefined, just return as no-op: * Happens during initial modesetting of a crtc. */ if (framedur_ns == 0) { DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc); return -EAGAIN; } return -EIO; } EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); /** * drm_vblank_off - disable vblank events on a CRTC * @dev: DRM device * @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. * * This is the legacy version of drm_crtc_vblank_off(). */ void drm_vblank_off(struct drm_device *dev, int crtc) { struct drm_pending_vblank_event *e, *t; struct timeval now; unsigned long irqflags; unsigned int seq; } EXPORT_SYMBOL(drm_vblank_off); /** * 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. * * This is the native kms version of drm_vblank_off(). */ void drm_crtc_vblank_off(struct drm_crtc *crtc) { drm_vblank_off(crtc->dev, drm_crtc_index(crtc)); } EXPORT_SYMBOL(drm_crtc_vblank_off); /** * drm_vblank_on - enable vblank events on a CRTC * @dev: DRM device * @crtc: CRTC in question * * This functions restores the vblank interrupt state captured with * drm_vblank_off() again. Note that calls to drm_vblank_on() and * drm_vblank_off() can be unbalanced and so can also be unconditionaly called * in driver load code to reflect the current hardware state of the crtc. * * This is the legacy version of drm_crtc_vblank_on(). */ void drm_vblank_on(struct drm_device *dev, int crtc) { unsigned long irqflags; } EXPORT_SYMBOL(drm_vblank_on); /** * drm_crtc_vblank_on - enable vblank events on a CRTC * @crtc: CRTC in question * * This functions restores the vblank interrupt state captured with * drm_vblank_off() again. Note that calls to drm_vblank_on() and * drm_vblank_off() can be unbalanced and so can also be unconditionaly called * in driver load code to reflect the current hardware state of the crtc. * * This is the native kms version of drm_vblank_on(). */ void drm_crtc_vblank_on(struct drm_crtc *crtc) { drm_vblank_on(crtc->dev, drm_crtc_index(crtc)); } EXPORT_SYMBOL(drm_crtc_vblank_on); /** * drm_vblank_pre_modeset - account for vblanks across mode sets * @dev: DRM device * @crtc: CRTC in question * * Account for vblank events across mode setting events, which will likely * reset the hardware frame counter. * * This is done by grabbing a temporary vblank reference to ensure that the * vblank interrupt keeps running across the modeset sequence. With this the * software-side vblank frame counting will ensure that there are no jumps or * discontinuities. * * Unfortunately this approach is racy and also doesn't work when the vblank * interrupt stops running, e.g. across system suspend resume. It is therefore * highly recommended that drivers use the newer drm_vblank_off() and * drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when * using "cooked" software vblank frame counters and not relying on any hardware * counters. * * Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc * again. */ void drm_vblank_pre_modeset(struct drm_device *dev, int crtc) { #if 0 /* vblank is not initialized (IRQ not installed ?) */ if (!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 (!dev->vblank[crtc].inmodeset) { dev->vblank[crtc].inmodeset = 0x1; if (drm_vblank_get(dev, crtc) == 0) dev->vblank[crtc].inmodeset |= 0x2; } #endif } EXPORT_SYMBOL(drm_vblank_pre_modeset); /** * drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes * @dev: DRM device * @crtc: CRTC in question * * This function again drops the temporary vblank reference acquired in * drm_vblank_pre_modeset. */ void drm_vblank_post_modeset(struct drm_device *dev, int crtc) { #if 0 unsigned long irqflags; /* vblank is not initialized (IRQ not installed ?), or has been freed */ if (!dev->num_crtcs) return; if (dev->vblank[crtc].inmodeset) { spin_lock_irqsave(&dev->vbl_lock, irqflags); dev->vblank_disable_allowed = true; spin_unlock_irqrestore(&dev->vbl_lock, irqflags); if (dev->vblank[crtc].inmodeset & 0x2) drm_vblank_put(dev, crtc); dev->vblank[crtc].inmodeset = 0; } #endif } EXPORT_SYMBOL(drm_vblank_post_modeset);