Commit 0af7e4df authored by Mario Kleiner's avatar Mario Kleiner Committed by Chris Wilson

drm/i915: Add support for precise vblank timestamping (v2)

v2: Change IS_IRONLAKE to IS_GEN5 to adapt to 2.6.37

This patch adds new functions for use by the drm core:

.get_vblank_timestamp() provides a precise timestamp
for the end of the most recent (or current) vblank
interval of a given crtc, as needed for the DRI2
implementation of the OML_sync_control extension.
It is a thin wrapper around the drm function
drm_calc_vbltimestamp_from_scanoutpos() which does
almost all the work.

.get_scanout_position() provides the current horizontal
and vertical video scanout position and "in vblank"
status of a given crtc, as needed by the drm for use by
drm_calc_vbltimestamp_from_scanoutpos().

The patch modifies the pageflip completion routine
to use these precise vblank timestamps as the timestamps
for pageflip completion events.

This code has been only tested on a HP-Mini Netbook with
Atom processor and Intel 945GME gpu. The codepath for
(IS_G4X(dev) || IS_GEN5(dev) || IS_GEN6(dev)) gpu's
has not been tested so far due to lack of hardware.
Signed-off-by: default avatarMario Kleiner <mario.kleiner@tuebingen.mpg.de>
Acked-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
parent d8c58fab
......@@ -652,6 +652,8 @@ static struct drm_driver driver = {
.device_is_agp = i915_driver_device_is_agp,
.enable_vblank = i915_enable_vblank,
.disable_vblank = i915_disable_vblank,
.get_vblank_timestamp = i915_get_vblank_timestamp,
.get_scanout_position = i915_get_crtc_scanoutpos,
.irq_preinstall = i915_driver_irq_preinstall,
.irq_postinstall = i915_driver_irq_postinstall,
.irq_uninstall = i915_driver_irq_uninstall,
......
......@@ -1019,6 +1019,13 @@ void
i915_disable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask);
void intel_enable_asle (struct drm_device *dev);
int i915_get_vblank_timestamp(struct drm_device *dev, int crtc,
int *max_error,
struct timeval *vblank_time,
unsigned flags);
int i915_get_crtc_scanoutpos(struct drm_device *dev, int pipe,
int *vpos, int *hpos);
#ifdef CONFIG_DEBUG_FS
extern void i915_destroy_error_state(struct drm_device *dev);
......
......@@ -248,6 +248,92 @@ u32 gm45_get_vblank_counter(struct drm_device *dev, int pipe)
return I915_READ(reg);
}
int i915_get_crtc_scanoutpos(struct drm_device *dev, int pipe,
int *vpos, int *hpos)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
u32 vbl = 0, position = 0;
int vbl_start, vbl_end, htotal, vtotal;
bool in_vbl = true;
int ret = 0;
if (!i915_pipe_enabled(dev, pipe)) {
DRM_DEBUG_DRIVER("trying to get scanoutpos for disabled "
"pipe %d\n", pipe);
return 0;
}
/* Get vtotal. */
vtotal = 1 + ((I915_READ(VTOTAL(pipe)) >> 16) & 0x1fff);
if (INTEL_INFO(dev)->gen >= 4) {
/* No obvious pixelcount register. Only query vertical
* scanout position from Display scan line register.
*/
position = I915_READ(PIPEDSL(pipe));
/* Decode into vertical scanout position. Don't have
* horizontal scanout position.
*/
*vpos = position & 0x1fff;
*hpos = 0;
} else {
/* Have access to pixelcount since start of frame.
* We can split this into vertical and horizontal
* scanout position.
*/
position = (I915_READ(PIPEFRAMEPIXEL(pipe)) & PIPE_PIXEL_MASK) >> PIPE_PIXEL_SHIFT;
htotal = 1 + ((I915_READ(HTOTAL(pipe)) >> 16) & 0x1fff);
*vpos = position / htotal;
*hpos = position - (*vpos * htotal);
}
/* Query vblank area. */
vbl = I915_READ(VBLANK(pipe));
/* Test position against vblank region. */
vbl_start = vbl & 0x1fff;
vbl_end = (vbl >> 16) & 0x1fff;
if ((*vpos < vbl_start) || (*vpos > vbl_end))
in_vbl = false;
/* Inside "upper part" of vblank area? Apply corrective offset: */
if (in_vbl && (*vpos >= vbl_start))
*vpos = *vpos - vtotal;
/* Readouts valid? */
if (vbl > 0)
ret |= DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE;
/* In vblank? */
if (in_vbl)
ret |= DRM_SCANOUTPOS_INVBL;
return ret;
}
int i915_get_vblank_timestamp(struct drm_device *dev, int crtc,
int *max_error,
struct timeval *vblank_time,
unsigned flags)
{
struct drm_crtc *drmcrtc;
if (crtc < 0 || crtc >= dev->num_crtcs) {
DRM_ERROR("Invalid crtc %d\n", crtc);
return -EINVAL;
}
/* Get drm_crtc to timestamp: */
drmcrtc = intel_get_crtc_for_pipe(dev, crtc);
/* Helper routine in DRM core does all the work: */
return drm_calc_vbltimestamp_from_scanoutpos(dev, crtc, max_error,
vblank_time, flags, drmcrtc);
}
/*
* Handle hotplug events outside the interrupt handler proper.
*/
......
......@@ -2253,6 +2253,7 @@
#define PIPESRC(pipe) _PIPE(pipe, PIPEASRC, PIPEBSRC)
#define PIPECONF(pipe) _PIPE(pipe, PIPEACONF, PIPEBCONF)
#define PIPEDSL(pipe) _PIPE(pipe, PIPEADSL, PIPEBDSL)
#define PIPEFRAMEPIXEL(pipe) _PIPE(pipe, PIPEAFRAMEPIXEL, PIPEBFRAMEPIXEL)
#define DSPARB 0x70030
#define DSPARB_CSTART_MASK (0x7f << 7)
......
......@@ -5252,7 +5252,8 @@ static void intel_unpin_work_fn(struct work_struct *__work)
}
static void do_intel_finish_page_flip(struct drm_device *dev,
struct drm_crtc *crtc)
struct drm_crtc *crtc,
int called_before_vblirq)
{
drm_i915_private_t *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
......@@ -5274,19 +5275,33 @@ static void do_intel_finish_page_flip(struct drm_device *dev,
}
intel_crtc->unpin_work = NULL;
drm_vblank_put(dev, intel_crtc->pipe);
if (work->event) {
e = work->event;
do_gettimeofday(&now);
e->event.sequence = drm_vblank_count(dev, intel_crtc->pipe);
e->event.sequence = drm_vblank_count_and_time(dev, intel_crtc->pipe, &now);
/* Called before vblank count and timestamps have
* been updated for the vblank interval of flip
* completion? Need to increment vblank count and
* add one videorefresh duration to returned timestamp
* to account for this.
*/
if (called_before_vblirq) {
e->event.sequence++;
now = ns_to_timeval(timeval_to_ns(&now) +
crtc->framedur_ns);
}
e->event.tv_sec = now.tv_sec;
e->event.tv_usec = now.tv_usec;
list_add_tail(&e->base.link,
&e->base.file_priv->event_list);
wake_up_interruptible(&e->base.file_priv->event_wait);
}
drm_vblank_put(dev, intel_crtc->pipe);
spin_unlock_irqrestore(&dev->event_lock, flags);
obj = work->old_fb_obj;
......@@ -5306,7 +5321,8 @@ void intel_finish_page_flip(struct drm_device *dev, int pipe)
drm_i915_private_t *dev_priv = dev->dev_private;
struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
do_intel_finish_page_flip(dev, crtc);
/* Called after drm_handle_vblank has run for finish vblank. */
do_intel_finish_page_flip(dev, crtc, 0);
}
void intel_finish_page_flip_plane(struct drm_device *dev, int plane)
......@@ -5314,7 +5330,8 @@ void intel_finish_page_flip_plane(struct drm_device *dev, int plane)
drm_i915_private_t *dev_priv = dev->dev_private;
struct drm_crtc *crtc = dev_priv->plane_to_crtc_mapping[plane];
do_intel_finish_page_flip(dev, crtc);
/* Called before drm_handle_vblank has run for finish vblank. */
do_intel_finish_page_flip(dev, crtc, 1);
}
void intel_prepare_page_flip(struct drm_device *dev, int plane)
......
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