From 0af7e4dff50454905092d468e91c1ef92e10e6b4 Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Wed, 8 Dec 2010 04:07:19 +0100 Subject: 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: Mario Kleiner Acked-by: Jesse Barnes Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_irq.c | 86 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) (limited to 'drivers/gpu/drm/i915/i915_irq.c') diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index e4a2e2c3dbe3..adf983f01dda 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -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. */ -- cgit v1.2.3