[PATCH 03/11] drm: Stop using linedur_ns and pixeldur_ns for vblank timestamps
ville.syrjala at linux.intel.com
ville.syrjala at linux.intel.com
Mon Sep 14 12:43:44 PDT 2015
From: Ville Syrjälä <ville.syrjala at linux.intel.com>
linedur_ns, and especially pixeldur_ns are becoming rather inaccurate
to be used for the vblank timestamp correction. With 4k at 60 the pixel
duration is already below 2ns, so the amount of error due to the
truncation to nanoseconds is introducing quite a bit of error.
We can avoid such problems if we instead calculate the timestamp
delta_ns directly from the dislay timings, avoiding the use of
these intermediate truncated values.
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
drivers/gpu/drm/drm_irq.c | 19 ++++++++-----------
drivers/gpu/drm/i915/i915_irq.c | 4 ++--
drivers/gpu/drm/nouveau/nouveau_display.c | 3 ++-
drivers/gpu/drm/nouveau/nouveau_display.h | 3 ++-
drivers/gpu/drm/radeon/radeon_display.c | 14 ++++++++------
drivers/gpu/drm/radeon/radeon_drv.c | 5 +++--
drivers/gpu/drm/radeon/radeon_mode.h | 5 +++--
drivers/gpu/drm/radeon/radeon_pm.c | 4 +++-
include/drm/drmP.h | 6 ++++--
9 files changed, 35 insertions(+), 28 deletions(-)
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 6b2fefd..9fab333 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -694,12 +694,11 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
unsigned flags,
const struct drm_display_mode *mode)
{
- struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
struct timeval tv_etime;
ktime_t stime, etime;
int vbl_status;
int vpos, hpos, i;
- int framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns;
+ int delta_ns, duration_ns;
bool invbl;
if (pipe >= dev->num_crtcs) {
@@ -713,15 +712,10 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
return -EIO;
}
- /* Durations of frames, lines, pixels in nanoseconds. */
- framedur_ns = vblank->framedur_ns;
- linedur_ns = vblank->linedur_ns;
- pixeldur_ns = vblank->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;
}
@@ -738,8 +732,10 @@ 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)) {
@@ -776,7 +772,8 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
* 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);
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 4aee725..77e8718 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -705,12 +705,12 @@ static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
static int i915_get_crtc_scanoutpos(struct drm_device *dev, int pipe,
unsigned int flags, int *vpos, int *hpos,
- ktime_t *stime, ktime_t *etime)
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
- const struct drm_display_mode *mode = &intel_crtc->base.hwmode;
int position;
int vbl_start, vbl_end, hsync_start, htotal, vtotal;
bool in_vbl = true;
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index 425515f..a82c3cb 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -133,7 +133,8 @@ nouveau_display_scanoutpos_head(struct drm_crtc *crtc, int *vpos, int *hpos,
int
nouveau_display_scanoutpos(struct drm_device *dev, int head, unsigned int flags,
- int *vpos, int *hpos, ktime_t *stime, ktime_t *etime)
+ int *vpos, int *hpos, ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode)
{
struct drm_crtc *crtc;
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h
index a6213e2..4182d21 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.h
+++ b/drivers/gpu/drm/nouveau/nouveau_display.h
@@ -68,7 +68,8 @@ void nouveau_display_resume(struct drm_device *dev, bool runtime);
int nouveau_display_vblank_enable(struct drm_device *, int);
void nouveau_display_vblank_disable(struct drm_device *, int);
int nouveau_display_scanoutpos(struct drm_device *, int, unsigned int,
- int *, int *, ktime_t *, ktime_t *);
+ int *, int *, ktime_t *, ktime_t *,
+ const struct drm_display_mode *);
int nouveau_display_vblstamp(struct drm_device *, int, int *,
struct timeval *, unsigned);
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index d2e9e9e..0503af7 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -323,7 +323,8 @@ void radeon_crtc_handle_vblank(struct radeon_device *rdev, int crtc_id)
*/
if (update_pending &&
(DRM_SCANOUTPOS_VALID & radeon_get_crtc_scanoutpos(rdev->ddev, crtc_id, 0,
- &vpos, &hpos, NULL, NULL)) &&
+ &vpos, &hpos, NULL, NULL,
+ &rdev->mode_info.crtcs[crtc_id]->base.hwmode)) &&
((vpos >= (99 * rdev->mode_info.crtcs[crtc_id]->base.hwmode.crtc_vdisplay)/100) ||
(vpos < 0 && !ASIC_IS_AVIVO(rdev)))) {
/* crtc didn't flip in this target vblank interval,
@@ -1799,7 +1800,8 @@ bool radeon_crtc_scaling_mode_fixup(struct drm_crtc *crtc,
*
*/
int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc, unsigned int flags,
- int *vpos, int *hpos, ktime_t *stime, ktime_t *etime)
+ int *vpos, int *hpos, ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode)
{
u32 stat_crtc = 0, vbl = 0, position = 0;
int vbl_start, vbl_end, vtotal, ret = 0;
@@ -1914,7 +1916,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc, unsigned int fl
}
else {
/* No: Fake something reasonable which gives at least ok results. */
- vbl_start = rdev->mode_info.crtcs[crtc]->base.hwmode.crtc_vdisplay;
+ vbl_start = mode->crtc_vdisplay;
vbl_end = 0;
}
@@ -1930,7 +1932,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc, unsigned int fl
/* Inside "upper part" of vblank area? Apply corrective offset if so: */
if (in_vbl && (*vpos >= vbl_start)) {
- vtotal = rdev->mode_info.crtcs[crtc]->base.hwmode.crtc_vtotal;
+ vtotal = mode->crtc_vtotal;
*vpos = *vpos - vtotal;
}
@@ -1952,8 +1954,8 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc, unsigned int fl
* We only do this if DRM_CALLED_FROM_VBLIRQ.
*/
if ((flags & DRM_CALLED_FROM_VBLIRQ) && !in_vbl) {
- vbl_start = rdev->mode_info.crtcs[crtc]->base.hwmode.crtc_vdisplay;
- vtotal = rdev->mode_info.crtcs[crtc]->base.hwmode.crtc_vtotal;
+ vbl_start = mode->crtc_vdisplay;
+ vtotal = mode->crtc_vtotal;
if (vbl_start - *vpos < vtotal / 100) {
*vpos -= vtotal;
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 5751446..e30c1d7 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -126,8 +126,9 @@ struct dma_buf *radeon_gem_prime_export(struct drm_device *dev,
int flags);
extern int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc,
unsigned int flags,
- int *vpos, int *hpos, ktime_t *stime,
- ktime_t *etime);
+ int *vpos, int *hpos,
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode);
extern bool radeon_is_px(struct drm_device *dev);
extern const struct drm_ioctl_desc radeon_ioctls_kms[];
extern int radeon_max_kms_ioctl;
diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index aecc3e3..2317d04 100644
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -876,8 +876,9 @@ extern void radeon_cursor_reset(struct drm_crtc *crtc);
extern int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc,
unsigned int flags,
- int *vpos, int *hpos, ktime_t *stime,
- ktime_t *etime);
+ int *vpos, int *hpos,
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode);
extern bool radeon_combios_check_hardcoded_edid(struct radeon_device *rdev);
extern struct edid *
diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index 05751f3..10f4c12 100644
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -1733,7 +1733,9 @@ static bool radeon_pm_in_vbl(struct radeon_device *rdev)
*/
for (crtc = 0; (crtc < rdev->num_crtc) && in_vbl; crtc++) {
if (rdev->pm.active_crtcs & (1 << crtc)) {
- vbl_status = radeon_get_crtc_scanoutpos(rdev->ddev, crtc, 0, &vpos, &hpos, NULL, NULL);
+ vbl_status = radeon_get_crtc_scanoutpos(rdev->ddev, crtc, 0,
+ &vpos, &hpos, NULL, NULL,
+ &rdev->mode_info.crtcs[crtc]->base.hwmode);
if ((vbl_status & DRM_SCANOUTPOS_VALID) &&
!(vbl_status & DRM_SCANOUTPOS_IN_VBLANK))
in_vbl = false;
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 2998867..b2a95e7 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -482,6 +482,7 @@ struct drm_driver {
* scanout position query. Can be NULL to skip timestamp.
* \param *etime Target location for timestamp taken immediately after
* scanout position query. Can be NULL to skip timestamp.
+ * \param mode Current display timings.
*
* Returns vpos as a positive number while in active scanout area.
* Returns vpos as a negative number inside vblank, counting the number
@@ -499,8 +500,9 @@ struct drm_driver {
*/
int (*get_scanout_position) (struct drm_device *dev, int crtc,
unsigned int flags,
- int *vpos, int *hpos, ktime_t *stime,
- ktime_t *etime);
+ int *vpos, int *hpos,
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode);
/**
* Called by \c drm_get_last_vbltimestamp. Should return a precise
--
2.4.6
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