diff options
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 331 |
1 files changed, 161 insertions, 170 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 22d207e..ed2394e 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -74,22 +74,22 @@ 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); -static void store_vblank(struct drm_device *dev, int crtc, +static void store_vblank(struct drm_device *dev, unsigned int pipe, u32 vblank_count_inc, - struct timeval *t_vblank) + struct timeval *t_vblank, u32 last) { - struct drm_vblank_crtc *vblank = &dev->vblank[crtc]; + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; u32 tslot; assert_spin_locked(&dev->vblank_time_lock); - if (t_vblank) { - /* All writers hold the spinlock, but readers are serialized by - * the latching of vblank->count below. - */ - tslot = vblank->count + vblank_count_inc; - vblanktimestamp(dev, crtc, tslot) = *t_vblank; - } + vblank->last = last; + + /* All writers hold the spinlock, but readers are serialized by + * the latching of vblank->count below. + */ + tslot = vblank->count + vblank_count_inc; + vblanktimestamp(dev, pipe, tslot) = *t_vblank; /* * vblank timestamp updates are protected on the write side with @@ -105,12 +105,60 @@ static void store_vblank(struct drm_device *dev, int crtc, } /** + * drm_reset_vblank_timestamp - reset the last timestamp to the last vblank + * @dev: DRM device + * @pipe: index of CRTC for which to reset the timestamp + * + * Reset the stored timestamp for the current vblank count to correspond + * to the last vblank occurred. + * + * Only to be called from drm_vblank_on(). + * + * Note: caller must hold dev->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 = dev->driver->get_vblank_counter(dev, pipe); + rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0); + } while (cur_vblank != dev->driver->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); +} + +/** * drm_update_vblank_count - update the master vblank counter * @dev: DRM device * @pipe: counter to update * * Call back into the driver to update the appropriate vblank counter - * (specified by @crtc). Deal with wraparound, if it occurred, and + * (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. * @@ -120,12 +168,15 @@ static void store_vblank(struct drm_device *dev, int crtc, * Note: caller must hold dev->vbl_lock since this reads & writes * device vblank fields. */ -static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe) +static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, + unsigned long flags) { 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 @@ -141,23 +192,43 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe) */ do { cur_vblank = dev->driver->get_vblank_counter(dev, pipe); - rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0); - } while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe)); + rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, flags); + } while (cur_vblank != dev->driver->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; - /* Deal with counter wrap */ - diff = cur_vblank - vblank->last; - if (cur_vblank < vblank->last) { - diff += dev->max_vblank_count + 1; + t_old = &vblanktimestamp(dev, pipe, vblank->count); + 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); - DRM_DEBUG("last_vblank[%u]=0x%x, cur_vblank=0x%x => diff=0x%x\n", - pipe, vblank->last, cur_vblank, diff); + if (diff == 0 && flags & DRM_CALLED_FROM_VBLIRQ) + DRM_DEBUG("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 = (flags & DRM_CALLED_FROM_VBLIRQ) != 0; } - DRM_DEBUG("updating vblank count on crtc %u, missed %d\n", - pipe, diff); + DRM_DEBUG("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) + if (diff == 0) { + WARN_ON_ONCE(cur_vblank != vblank->last); return; + } /* * Only reinitialize corresponding vblank timestamp if high-precision query @@ -167,7 +238,7 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe) if (!rc) t_vblank = (struct timeval) {0, 0}; - store_vblank(dev, pipe, diff, &t_vblank); + store_vblank(dev, pipe, diff, &t_vblank, cur_vblank); } /* @@ -180,11 +251,6 @@ static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) { struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; unsigned long irqflags; - u32 vblcount; - s64 diff_ns; - bool vblrc; - struct timeval tvblank; - int count = DRM_TIMESTAMP_MAXRETRIES; /* Prevent vblank irq processing while disabling vblank irqs, * so no updates of timestamps or count can happen after we've @@ -193,26 +259,6 @@ static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) spin_lock_irqsave(&dev->vblank_time_lock, irqflags); /* - * If the vblank interrupt was already disabled 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_vblank_on() and - * drm_vblank_off(). - * - * But only do this if precise vblank timestamps are available. - * Otherwise we might read a totally bogus timestamp since drivers - * lacking precise timestamp support rely upon sampling the system clock - * at vblank interrupt time. Which obviously won't work out well if the - * vblank interrupt is disabled. - */ - if (!vblank->enabled && - drm_get_last_vbltimestamp(dev, pipe, &tvblank, 0)) { - drm_update_vblank_count(dev, pipe); - spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); - return; - } - - /* * Only disable vblank interrupts if they're enabled. This avoids * calling the ->disable_vblank() operation in atomic context with the * hardware potentially runtime suspended. @@ -222,47 +268,13 @@ static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) vblank->enabled = false; } - /* No further vblank irq's will be processed after - * this point. Get current hardware vblank count and - * vblank timestamp, repeat until they are consistent. - * - * FIXME: There is still a race condition here and in - * drm_update_vblank_count() which can cause off-by-one - * reinitialization of software vblank counter. If gpu - * vblank counter doesn't increment exactly at the leading - * edge of a vblank interval, then we can lose 1 count if - * we happen to execute between start of vblank and the - * delayed gpu counter increment. - */ - do { - vblank->last = dev->driver->get_vblank_counter(dev, pipe); - vblrc = drm_get_last_vbltimestamp(dev, pipe, &tvblank, 0); - } while (vblank->last != dev->driver->get_vblank_counter(dev, pipe) && (--count) && vblrc); - - if (!count) - vblrc = 0; - - /* Compute time difference to stored timestamp of last vblank - * as updated by last invocation of drm_handle_vblank() in vblank irq. - */ - vblcount = vblank->count; - diff_ns = timeval_to_ns(&tvblank) - - timeval_to_ns(&vblanktimestamp(dev, pipe, vblcount)); - - /* If there is at least 1 msec difference between the last stored - * timestamp and tvblank, then we are currently executing our - * disable inside a new vblank interval, the tvblank timestamp - * corresponds to this new vblank interval and the irq handler - * for this vblank didn't run yet and won't run due to our disable. - * Therefore we need to do the job of drm_handle_vblank() and - * increment the vblank counter by one to account for this vblank. - * - * Skip this step if there isn't any high precision timestamp - * available. In that case we can't account for this and just - * hope for the best. + /* + * 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_vblank_on() and drm_vblank_off(). */ - if (vblrc && (abs64(diff_ns) > 1000000)) - store_vblank(dev, pipe, 1, &tvblank); + drm_update_vblank_count(dev, pipe, 0); spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); } @@ -603,7 +615,8 @@ int drm_control(struct drm_device *dev, void *data, 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; + struct drm_vblank_crtc *vblank = &crtc->dev->vblank[drm_crtc_index(crtc)]; + int linedur_ns = 0, framedur_ns = 0; int dotclock = mode->crtc_clock; /* Valid dotclock? */ @@ -612,10 +625,9 @@ void drm_calc_timestamping_constants(struct drm_crtc *crtc, /* * Convert scanline length in pixels and video - * dot clock to line duration, frame duration - * and pixel duration in nanoseconds: + * dot clock to line duration and frame 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); @@ -628,16 +640,14 @@ void drm_calc_timestamping_constants(struct drm_crtc *crtc, DRM_ERROR("crtc %u: 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; + vblank->linedur_ns = linedur_ns; + vblank->framedur_ns = framedur_ns; 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, pixeldur %d\n", - crtc->base.id, dotclock, framedur_ns, - linedur_ns, pixeldur_ns); + 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); @@ -651,7 +661,6 @@ EXPORT_SYMBOL(drm_calc_timestamping_constants); * @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 @@ -692,15 +701,14 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int *max_error, struct timeval *vblank_time, unsigned flags, - const struct drm_crtc *refcrtc, const struct drm_display_mode *mode) { struct timeval tv_etime; ktime_t stime, etime; - int vbl_status; + unsigned int vbl_status; + int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD; int vpos, hpos, i; - int framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns; - bool invbl; + int delta_ns, duration_ns; if (pipe >= dev->num_crtcs) { DRM_ERROR("Invalid crtc %u\n", pipe); @@ -713,15 +721,10 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, 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) { + if (mode->crtc_clock == 0) { DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe); return -EAGAIN; } @@ -738,12 +741,14 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, * 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, flags, &vpos, - &hpos, &stime, &etime); + vbl_status = dev->driver->get_scanout_position(dev, pipe, flags, + &vpos, &hpos, + &stime, &etime, + mode); /* Return as no-op if scanout query unsupported or failed. */ if (!(vbl_status & DRM_SCANOUTPOS_VALID)) { - DRM_DEBUG("crtc %u : scanoutpos query failed [%d].\n", + DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n", pipe, vbl_status); return -EIO; } @@ -770,13 +775,15 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, * within vblank area, counting down the number of lines until * start of scanout. */ - invbl = vbl_status & DRM_SCANOUTPOS_IN_VBLANK; + if (vbl_status & DRM_SCANOUTPOS_IN_VBLANK) + ret |= DRM_VBLANKTIME_IN_VBLANK; /* 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 = vpos * linedur_ns + hpos * pixeldur_ns; + delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos), + mode->crtc_clock); if (!drm_timestamp_monotonic) etime = ktime_mono_to_real(etime); @@ -792,17 +799,13 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, etime = ktime_sub_ns(etime, delta_ns); *vblank_time = ktime_to_timeval(etime); - DRM_DEBUG("crtc %u : v %d p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", - pipe, (int)vbl_status, hpos, vpos, + DRM_DEBUG("crtc %u : v 0x%x p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", + pipe, vbl_status, 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); - vbl_status = DRM_VBLANKTIME_SCANOUTPOS_METHOD; - if (invbl) - vbl_status |= DRM_VBLANKTIME_IN_VBLANK; - - return vbl_status; + return ret; } EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); @@ -914,11 +917,14 @@ EXPORT_SYMBOL(drm_crtc_vblank_count); * 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(). */ u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, struct timeval *vblanktime) { struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + int count = DRM_TIMESTAMP_MAXRETRIES; u32 cur_vblank; if (WARN_ON(pipe >= dev->num_crtcs)) @@ -934,12 +940,33 @@ u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, smp_rmb(); *vblanktime = vblanktimestamp(dev, pipe, cur_vblank); smp_rmb(); - } while (cur_vblank != vblank->count); + } while (cur_vblank != vblank->count && --count > 0); return cur_vblank; } EXPORT_SYMBOL(drm_vblank_count_and_time); +/** + * 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. + * + * This is the native KMS version of drm_vblank_count_and_time(). + */ +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) @@ -1033,7 +1060,7 @@ static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe) atomic_dec(&vblank->refcount); else { vblank->enabled = true; - drm_update_vblank_count(dev, pipe); + drm_update_vblank_count(dev, pipe, 0); } } @@ -1154,8 +1181,8 @@ EXPORT_SYMBOL(drm_crtc_vblank_put); * @dev: DRM device * @pipe: CRTC index * - * 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. + * 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) @@ -1276,7 +1303,7 @@ EXPORT_SYMBOL(drm_crtc_vblank_off); /** * drm_crtc_vblank_reset - reset vblank state to off on a CRTC - * @drm_crtc: CRTC in question + * @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 @@ -1284,12 +1311,12 @@ EXPORT_SYMBOL(drm_crtc_vblank_off); * 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 *drm_crtc) +void drm_crtc_vblank_reset(struct drm_crtc *crtc) { - struct drm_device *dev = drm_crtc->dev; + struct drm_device *dev = crtc->dev; unsigned long irqflags; - int crtc = drm_crtc_index(drm_crtc); - struct drm_vblank_crtc *vblank = &dev->vblank[crtc]; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; spin_lock_irqsave(&dev->vbl_lock, irqflags); /* @@ -1333,16 +1360,8 @@ void drm_vblank_on(struct drm_device *dev, unsigned int pipe) vblank->inmodeset = 0; } - /* - * sample the current counter to avoid random jumps - * when drm_vblank_enable() applies the diff - * - * -1 to make sure user will never see the same - * vblank counter value before and after a modeset - */ - vblank->last = - (dev->driver->get_vblank_counter(dev, pipe) - 1) & - dev->max_vblank_count; + 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. @@ -1725,9 +1744,6 @@ static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe) bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) { struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - u32 vblcount; - s64 diff_ns; - struct timeval tvblank; unsigned long irqflags; if (WARN_ON_ONCE(!dev->num_crtcs)) @@ -1751,32 +1767,7 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) return false; } - /* Fetch corresponding timestamp for this vblank interval from - * driver and store it in proper slot of timestamp ringbuffer. - */ - - /* Get current timestamp and count. */ - vblcount = vblank->count; - drm_get_last_vbltimestamp(dev, pipe, &tvblank, DRM_CALLED_FROM_VBLIRQ); - - /* Compute time difference to timestamp of last vblank */ - diff_ns = timeval_to_ns(&tvblank) - - timeval_to_ns(&vblanktimestamp(dev, pipe, vblcount)); - - /* Update vblank timestamp and count if at least - * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds - * difference between last stored timestamp and current - * timestamp. A smaller difference means basically - * identical timestamps. Happens if this vblank has - * been already processed and this is a redundant call, - * e.g., due to spurious vblank interrupts. We need to - * ignore those for accounting. - */ - if (abs64(diff_ns) > DRM_REDUNDANT_VBLIRQ_THRESH_NS) - store_vblank(dev, pipe, 1, &tvblank); - else - DRM_DEBUG("crtc %u: Redundant vblirq ignored. diff_ns = %d\n", - pipe, (int) diff_ns); + drm_update_vblank_count(dev, pipe, DRM_CALLED_FROM_VBLIRQ); spin_unlock(&dev->vblank_time_lock); |
