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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:37 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:37 +0000 |
commit | 94ac2ab3fff96814d7460a27a0e9d004abbd4128 (patch) | |
tree | 9a4eb8cc234b540b0f4b93363109cdd37a20540b /drivers/gpu/drm/i915/display/intel_vblank.c | |
parent | Adding debian version 6.8.12-1. (diff) | |
download | linux-94ac2ab3fff96814d7460a27a0e9d004abbd4128.tar.xz linux-94ac2ab3fff96814d7460a27a0e9d004abbd4128.zip |
Merging upstream version 6.9.2.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_vblank.c')
-rw-r--r-- | drivers/gpu/drm/i915/display/intel_vblank.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_vblank.c b/drivers/gpu/drm/i915/display/intel_vblank.c index fe256bf7b4..baf7354cb6 100644 --- a/drivers/gpu/drm/i915/display/intel_vblank.c +++ b/drivers/gpu/drm/i915/display/intel_vblank.c @@ -5,6 +5,7 @@ #include "i915_drv.h" #include "i915_reg.h" +#include "intel_crtc.h" #include "intel_de.h" #include "intel_display_types.h" #include "intel_vblank.h" @@ -581,3 +582,132 @@ void intel_crtc_update_active_timings(const struct intel_crtc_state *crtc_state, intel_vblank_section_exit(i915); spin_unlock_irqrestore(&i915->drm.vblank_time_lock, irqflags); } + +static int intel_mode_vblank_start(const struct drm_display_mode *mode) +{ + int vblank_start = mode->crtc_vblank_start; + + if (mode->flags & DRM_MODE_FLAG_INTERLACE) + vblank_start = DIV_ROUND_UP(vblank_start, 2); + + return vblank_start; +} + +void intel_vblank_evade_init(const struct intel_crtc_state *old_crtc_state, + const struct intel_crtc_state *new_crtc_state, + struct intel_vblank_evade_ctx *evade) +{ + struct intel_crtc *crtc = to_intel_crtc(new_crtc_state->uapi.crtc); + struct drm_i915_private *i915 = to_i915(crtc->base.dev); + const struct intel_crtc_state *crtc_state; + const struct drm_display_mode *adjusted_mode; + + evade->crtc = crtc; + + evade->need_vlv_dsi_wa = (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) && + intel_crtc_has_type(new_crtc_state, INTEL_OUTPUT_DSI); + + /* + * During fastsets/etc. the transcoder is still + * running with the old timings at this point. + * + * TODO: maybe just use the active timings here? + */ + if (intel_crtc_needs_modeset(new_crtc_state)) + crtc_state = new_crtc_state; + else + crtc_state = old_crtc_state; + + adjusted_mode = &crtc_state->hw.adjusted_mode; + + if (crtc->mode_flags & I915_MODE_FLAG_VRR) { + /* timing changes should happen with VRR disabled */ + drm_WARN_ON(crtc->base.dev, intel_crtc_needs_modeset(new_crtc_state) || + new_crtc_state->update_m_n || new_crtc_state->update_lrr); + + if (intel_vrr_is_push_sent(crtc_state)) + evade->vblank_start = intel_vrr_vmin_vblank_start(crtc_state); + else + evade->vblank_start = intel_vrr_vmax_vblank_start(crtc_state); + } else { + evade->vblank_start = intel_mode_vblank_start(adjusted_mode); + } + + /* FIXME needs to be calibrated sensibly */ + evade->min = evade->vblank_start - intel_usecs_to_scanlines(adjusted_mode, + VBLANK_EVASION_TIME_US); + evade->max = evade->vblank_start - 1; + + /* + * M/N and TRANS_VTOTAL are double buffered on the transcoder's + * undelayed vblank, so with seamless M/N and LRR we must evade + * both vblanks. + * + * DSB execution waits for the transcoder's undelayed vblank, + * hence we must kick off the commit before that. + */ + if (new_crtc_state->dsb || new_crtc_state->update_m_n || new_crtc_state->update_lrr) + evade->min -= adjusted_mode->crtc_vblank_start - adjusted_mode->crtc_vdisplay; +} + +/* must be called with vblank interrupt already enabled! */ +int intel_vblank_evade(struct intel_vblank_evade_ctx *evade) +{ + struct intel_crtc *crtc = evade->crtc; + struct drm_i915_private *i915 = to_i915(crtc->base.dev); + long timeout = msecs_to_jiffies_timeout(1); + wait_queue_head_t *wq = drm_crtc_vblank_waitqueue(&crtc->base); + DEFINE_WAIT(wait); + int scanline; + + if (evade->min <= 0 || evade->max <= 0) + return 0; + + for (;;) { + /* + * prepare_to_wait() has a memory barrier, which guarantees + * other CPUs can see the task state update by the time we + * read the scanline. + */ + prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE); + + scanline = intel_get_crtc_scanline(crtc); + if (scanline < evade->min || scanline > evade->max) + break; + + if (!timeout) { + drm_err(&i915->drm, + "Potential atomic update failure on pipe %c\n", + pipe_name(crtc->pipe)); + break; + } + + local_irq_enable(); + + timeout = schedule_timeout(timeout); + + local_irq_disable(); + } + + finish_wait(wq, &wait); + + /* + * On VLV/CHV DSI the scanline counter would appear to + * increment approx. 1/3 of a scanline before start of vblank. + * The registers still get latched at start of vblank however. + * This means we must not write any registers on the first + * line of vblank (since not the whole line is actually in + * vblank). And unfortunately we can't use the interrupt to + * wait here since it will fire too soon. We could use the + * frame start interrupt instead since it will fire after the + * critical scanline, but that would require more changes + * in the interrupt code. So for now we'll just do the nasty + * thing and poll for the bad scanline to pass us by. + * + * FIXME figure out if BXT+ DSI suffers from this as well + */ + while (evade->need_vlv_dsi_wa && scanline == evade->vblank_start) + scanline = intel_get_crtc_scanline(crtc); + + return scanline; +} |