[PATCH 3/5] drm/i915: Call i915_pipe_update_start with uncore.lock held.

Maarten Lankhorst
2018-02-09T09:54:57Z

This requires being able to read the vblank counter with the
uncore.lock already held. This is also a preparation for
being able to run the entire vblank update sequence with
the uncore lock held.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
drivers/gpu/drm/i915/i915_irq.c | 66 ++++++++++++++++++++++++++++++-------
drivers/gpu/drm/i915/i915_trace.h | 5 ++-
drivers/gpu/drm/i915/intel_drv.h | 1 +
drivers/gpu/drm/i915/intel_sprite.c | 3 +-
4 files changed, 60 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index eda9543a0199..6c491e63e07c 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -736,13 +736,12 @@ static void i915_enable_asle_pipestat(struct drm_i915_private *dev_priv)
/* Called from drm generic code, passed a 'crtc', which
* we use as a pipe index
*/
-static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
+static u32 __i915_get_vblank_counter(struct intel_crtc *crtc)
{
- struct drm_i915_private *dev_priv = to_i915(dev);
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
i915_reg_t high_frame, low_frame;
u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
- const struct drm_display_mode *mode = &dev->vblank[pipe].hwmode;
- unsigned long irqflags;
+ const struct drm_display_mode *mode = &crtc->base.dev->vblank[crtc->pipe].hwmode;

htotal = mode->crtc_htotal;
hsync_start = mode->crtc_hsync_start;
@@ -756,10 +755,8 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
/* Start of vblank event occurs at start of hsync */
vbl_start -= htotal - hsync_start;

- high_frame = PIPEFRAME(pipe);
- low_frame = PIPEFRAMEPIXEL(pipe);
-
- spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ high_frame = PIPEFRAME(crtc->pipe);
+ low_frame = PIPEFRAMEPIXEL(crtc->pipe);

/*
* High & low register fields aren't synchronized, so make sure
@@ -772,8 +769,6 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
high2 = I915_READ_FW(high_frame) & PIPE_FRAME_HIGH_MASK;
} while (high1 != high2);

- spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
-
high1 >>= PIPE_FRAME_HIGH_SHIFT;
pixel = low & PIPE_PIXEL_MASK;
low >>= PIPE_FRAME_LOW_SHIFT;
@@ -786,11 +781,60 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff;
}

+static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
+{
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ unsigned long irqflags;
+ u32 ret;
+
+ spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ ret = i915_get_vblank_counter(dev, pipe);
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+
+ return ret;
+}
+
+static u32 __g4x_get_vblank_counter(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+
+ return I915_READ_FW(PIPE_FRMCOUNT_G4X(crtc->pipe));
+}
+
static u32 g4x_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
{
struct drm_i915_private *dev_priv = to_i915(dev);
+ struct intel_crtc *crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
+ unsigned long irqflags;
+ u32 ret;
+
+ spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ ret = __g4x_get_vblank_counter(crtc);
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+
+ return ret;
+}
+
+u32 __intel_crtc_get_vblank_counter(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+
+ if (IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5)
+ return __g4x_get_vblank_counter(crtc);
+ else if (IS_GEN2(dev_priv))
+ return 0;
+ else
+ return __i915_get_vblank_counter(crtc);
+}
+
+u32 intel_crtc_get_vblank_counter(struct intel_crtc *crtc)
+{
+ struct drm_device *dev = crtc->base.dev;
+
+ if (!dev->max_vblank_count)
+ return drm_crtc_accurate_vblank_count(&crtc->base);

- return I915_READ(PIPE_FRMCOUNT_G4X(pipe));
+ return dev->driver->get_vblank_counter(dev, crtc->pipe);
}

/*
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index e1169c02eb2b..d4a5776282ff 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -280,9 +280,8 @@ TRACE_EVENT(i915_pipe_update_start,

TP_fast_assign(
__entry->pipe = crtc->pipe;
- __entry->frame = crtc->base.dev->driver->get_vblank_counter(crtc->base.dev,
- crtc->pipe);
- __entry->scanline = intel_get_crtc_scanline(crtc);
+ __entry->frame = __intel_crtc_get_vblank_counter(crtc);
+ __entry->scanline = __intel_get_crtc_scanline(crtc);
__entry->min = crtc->debug.min_vbl;
__entry->max = crtc->debug.max_vbl;
),
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index fbdbbe741b2f..048fcd3c960e 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1489,6 +1489,7 @@ intel_wait_for_vblank_if_active(struct drm_i915_private *dev_priv, int pipe)
}

u32 intel_crtc_get_vblank_counter(struct intel_crtc *crtc);
+u32 __intel_crtc_get_vblank_counter(struct intel_crtc *crtc);

int ironlake_get_lanes_required(int target_clock, int link_bw, int bpp);
void vlv_wait_port_ready(struct drm_i915_private *dev_priv,
diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 3a34be4fd956..95f0999ea18a 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -117,9 +117,10 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)

crtc->debug.min_vbl = min;
crtc->debug.max_vbl = max;
- trace_i915_pipe_update_start(crtc);

spin_lock(&dev_priv->uncore.lock);
+ trace_i915_pipe_update_start(crtc);
+
for (;;) {
/*
* prepare_to_wait() has a memory barrier, which guarantees
--
2.16.1