[Intel-gfx] [PATCH v2 1/5] drm/i915/irq: split out vblank/scanline code to intel_vblank.[ch]
Jani Nikula
jani.nikula at intel.com
Mon Jan 16 12:56:12 UTC 2023
The vblank/scanline code is fairly isolated in i915_irq.c. Split it out
to new intel_vblank.[ch].
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
drivers/gpu/drm/i915/Makefile | 1 +
drivers/gpu/drm/i915/display/intel_crtc.c | 1 +
.../drm/i915/display/intel_display_trace.h | 1 +
drivers/gpu/drm/i915/display/intel_vblank.c | 419 ++++++++++++++++++
drivers/gpu/drm/i915/display/intel_vblank.h | 21 +
drivers/gpu/drm/i915/i915_irq.c | 408 -----------------
drivers/gpu/drm/i915/i915_irq.h | 6 -
7 files changed, 443 insertions(+), 414 deletions(-)
create mode 100644 drivers/gpu/drm/i915/display/intel_vblank.c
create mode 100644 drivers/gpu/drm/i915/display/intel_vblank.h
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index f47f00b162a4..2184bc5b2be7 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -266,6 +266,7 @@ i915-y += \
display/intel_quirks.o \
display/intel_sprite.o \
display/intel_tc.o \
+ display/intel_vblank.o \
display/intel_vga.o \
display/i9xx_plane.o \
display/skl_scaler.o \
diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
index 037fc140b585..82be0fbe9934 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc.c
@@ -28,6 +28,7 @@
#include "intel_pipe_crc.h"
#include "intel_psr.h"
#include "intel_sprite.h"
+#include "intel_vblank.h"
#include "intel_vrr.h"
#include "skl_universal_plane.h"
diff --git a/drivers/gpu/drm/i915/display/intel_display_trace.h b/drivers/gpu/drm/i915/display/intel_display_trace.h
index 725aba3fa531..651ea8564e1b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_trace.h
+++ b/drivers/gpu/drm/i915/display/intel_display_trace.h
@@ -17,6 +17,7 @@
#include "i915_irq.h"
#include "intel_crtc.h"
#include "intel_display_types.h"
+#include "intel_vblank.h"
#define __dev_name_i915(i915) dev_name((i915)->drm.dev)
#define __dev_name_kms(obj) dev_name((obj)->base.dev->dev)
diff --git a/drivers/gpu/drm/i915/display/intel_vblank.c b/drivers/gpu/drm/i915/display/intel_vblank.c
new file mode 100644
index 000000000000..6392a56ae7d4
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_vblank.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022-2023 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "i915_reg.h"
+#include "intel_de.h"
+#include "intel_display_types.h"
+#include "intel_vblank.h"
+
+/*
+ * This timing diagram depicts the video signal in and
+ * around the vertical blanking period.
+ *
+ * Assumptions about the fictitious mode used in this example:
+ * vblank_start >= 3
+ * vsync_start = vblank_start + 1
+ * vsync_end = vblank_start + 2
+ * vtotal = vblank_start + 3
+ *
+ * start of vblank:
+ * latch double buffered registers
+ * increment frame counter (ctg+)
+ * generate start of vblank interrupt (gen4+)
+ * |
+ * | frame start:
+ * | generate frame start interrupt (aka. vblank interrupt) (gmch)
+ * | may be shifted forward 1-3 extra lines via PIPECONF
+ * | |
+ * | | start of vsync:
+ * | | generate vsync interrupt
+ * | | |
+ * ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx
+ * . \hs/ . \hs/ \hs/ \hs/ . \hs/
+ * ----va---> <-----------------vb--------------------> <--------va-------------
+ * | | <----vs-----> |
+ * -vbs-----> <---vbs+1---> <---vbs+2---> <-----0-----> <-----1-----> <-----2--- (scanline counter gen2)
+ * -vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2---> <-----0--- (scanline counter gen3+)
+ * -vbs-2---> <---vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2- (scanline counter hsw+ hdmi)
+ * | | |
+ * last visible pixel first visible pixel
+ * | increment frame counter (gen3/4)
+ * pixel counter = vblank_start * htotal pixel counter = 0 (gen3/4)
+ *
+ * x = horizontal active
+ * _ = horizontal blanking
+ * hs = horizontal sync
+ * va = vertical active
+ * vb = vertical blanking
+ * vs = vertical sync
+ * vbs = vblank_start (number)
+ *
+ * Summary:
+ * - most events happen at the start of horizontal sync
+ * - frame start happens at the start of horizontal blank, 1-4 lines
+ * (depending on PIPECONF settings) after the start of vblank
+ * - gen3/4 pixel and frame counter are synchronized with the start
+ * of horizontal active on the first line of vertical active
+ */
+
+/*
+ * Called from drm generic code, passed a 'crtc', which we use as a pipe index.
+ */
+u32 i915_get_vblank_counter(struct drm_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+ struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[drm_crtc_index(crtc)];
+ const struct drm_display_mode *mode = &vblank->hwmode;
+ enum pipe pipe = to_intel_crtc(crtc)->pipe;
+ i915_reg_t high_frame, low_frame;
+ u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
+ unsigned long irqflags;
+
+ /*
+ * On i965gm TV output the frame counter only works up to
+ * the point when we enable the TV encoder. After that the
+ * frame counter ceases to work and reads zero. We need a
+ * vblank wait before enabling the TV encoder and so we
+ * have to enable vblank interrupts while the frame counter
+ * is still in a working state. However the core vblank code
+ * does not like us returning non-zero frame counter values
+ * when we've told it that we don't have a working frame
+ * counter. Thus we must stop non-zero values leaking out.
+ */
+ if (!vblank->max_vblank_count)
+ return 0;
+
+ htotal = mode->crtc_htotal;
+ hsync_start = mode->crtc_hsync_start;
+ vbl_start = mode->crtc_vblank_start;
+ if (mode->flags & DRM_MODE_FLAG_INTERLACE)
+ vbl_start = DIV_ROUND_UP(vbl_start, 2);
+
+ /* Convert to pixel count */
+ vbl_start *= htotal;
+
+ /* 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 & low register fields aren't synchronized, so make sure
+ * we get a low value that's stable across two reads of the high
+ * register.
+ */
+ do {
+ high1 = intel_de_read_fw(dev_priv, high_frame) & PIPE_FRAME_HIGH_MASK;
+ low = intel_de_read_fw(dev_priv, low_frame);
+ high2 = intel_de_read_fw(dev_priv, 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;
+
+ /*
+ * The frame counter increments at beginning of active.
+ * Cook up a vblank counter by also checking the pixel
+ * counter against vblank start.
+ */
+ return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff;
+}
+
+u32 g4x_get_vblank_counter(struct drm_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+ struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[drm_crtc_index(crtc)];
+ enum pipe pipe = to_intel_crtc(crtc)->pipe;
+
+ if (!vblank->max_vblank_count)
+ return 0;
+
+ return intel_uncore_read(&dev_priv->uncore, PIPE_FRMCOUNT_G4X(pipe));
+}
+
+static u32 intel_crtc_scanlines_since_frame_timestamp(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct drm_vblank_crtc *vblank =
+ &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
+ const struct drm_display_mode *mode = &vblank->hwmode;
+ u32 htotal = mode->crtc_htotal;
+ u32 clock = mode->crtc_clock;
+ u32 scan_prev_time, scan_curr_time, scan_post_time;
+
+ /*
+ * To avoid the race condition where we might cross into the
+ * next vblank just between the PIPE_FRMTMSTMP and TIMESTAMP_CTR
+ * reads. We make sure we read PIPE_FRMTMSTMP and TIMESTAMP_CTR
+ * during the same frame.
+ */
+ do {
+ /*
+ * This field provides read back of the display
+ * pipe frame time stamp. The time stamp value
+ * is sampled at every start of vertical blank.
+ */
+ scan_prev_time = intel_de_read_fw(dev_priv,
+ PIPE_FRMTMSTMP(crtc->pipe));
+
+ /*
+ * The TIMESTAMP_CTR register has the current
+ * time stamp value.
+ */
+ scan_curr_time = intel_de_read_fw(dev_priv, IVB_TIMESTAMP_CTR);
+
+ scan_post_time = intel_de_read_fw(dev_priv,
+ PIPE_FRMTMSTMP(crtc->pipe));
+ } while (scan_post_time != scan_prev_time);
+
+ return div_u64(mul_u32_u32(scan_curr_time - scan_prev_time,
+ clock), 1000 * htotal);
+}
+
+/*
+ * On certain encoders on certain platforms, pipe
+ * scanline register will not work to get the scanline,
+ * since the timings are driven from the PORT or issues
+ * with scanline register updates.
+ * This function will use Framestamp and current
+ * timestamp registers to calculate the scanline.
+ */
+static u32 __intel_get_crtc_scanline_from_timestamp(struct intel_crtc *crtc)
+{
+ struct drm_vblank_crtc *vblank =
+ &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
+ const struct drm_display_mode *mode = &vblank->hwmode;
+ u32 vblank_start = mode->crtc_vblank_start;
+ u32 vtotal = mode->crtc_vtotal;
+ u32 scanline;
+
+ scanline = intel_crtc_scanlines_since_frame_timestamp(crtc);
+ scanline = min(scanline, vtotal - 1);
+ scanline = (scanline + vblank_start) % vtotal;
+
+ return scanline;
+}
+
+/*
+ * intel_de_read_fw(), only for fast reads of display block, no need for
+ * forcewake etc.
+ */
+static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
+{
+ struct drm_device *dev = crtc->base.dev;
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ const struct drm_display_mode *mode;
+ struct drm_vblank_crtc *vblank;
+ enum pipe pipe = crtc->pipe;
+ int position, vtotal;
+
+ if (!crtc->active)
+ return 0;
+
+ vblank = &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
+ mode = &vblank->hwmode;
+
+ if (crtc->mode_flags & I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP)
+ return __intel_get_crtc_scanline_from_timestamp(crtc);
+
+ vtotal = mode->crtc_vtotal;
+ if (mode->flags & DRM_MODE_FLAG_INTERLACE)
+ vtotal /= 2;
+
+ position = intel_de_read_fw(dev_priv, PIPEDSL(pipe)) & PIPEDSL_LINE_MASK;
+
+ /*
+ * On HSW, the DSL reg (0x70000) appears to return 0 if we
+ * read it just before the start of vblank. So try it again
+ * so we don't accidentally end up spanning a vblank frame
+ * increment, causing the pipe_update_end() code to squak at us.
+ *
+ * The nature of this problem means we can't simply check the ISR
+ * bit and return the vblank start value; nor can we use the scanline
+ * debug register in the transcoder as it appears to have the same
+ * problem. We may need to extend this to include other platforms,
+ * but so far testing only shows the problem on HSW.
+ */
+ if (HAS_DDI(dev_priv) && !position) {
+ int i, temp;
+
+ for (i = 0; i < 100; i++) {
+ udelay(1);
+ temp = intel_de_read_fw(dev_priv, PIPEDSL(pipe)) & PIPEDSL_LINE_MASK;
+ if (temp != position) {
+ position = temp;
+ break;
+ }
+ }
+ }
+
+ /*
+ * See update_scanline_offset() for the details on the
+ * scanline_offset adjustment.
+ */
+ return (position + crtc->scanline_offset) % vtotal;
+}
+
+static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
+ bool in_vblank_irq,
+ int *vpos, int *hpos,
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode)
+{
+ struct drm_device *dev = _crtc->dev;
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ struct intel_crtc *crtc = to_intel_crtc(_crtc);
+ enum pipe pipe = crtc->pipe;
+ int position;
+ int vbl_start, vbl_end, hsync_start, htotal, vtotal;
+ unsigned long irqflags;
+ bool use_scanline_counter = DISPLAY_VER(dev_priv) >= 5 ||
+ IS_G4X(dev_priv) || DISPLAY_VER(dev_priv) == 2 ||
+ crtc->mode_flags & I915_MODE_FLAG_USE_SCANLINE_COUNTER;
+
+ if (drm_WARN_ON(&dev_priv->drm, !mode->crtc_clock)) {
+ drm_dbg(&dev_priv->drm,
+ "trying to get scanoutpos for disabled pipe %c\n",
+ pipe_name(pipe));
+ return false;
+ }
+
+ htotal = mode->crtc_htotal;
+ hsync_start = mode->crtc_hsync_start;
+ vtotal = mode->crtc_vtotal;
+ vbl_start = mode->crtc_vblank_start;
+ vbl_end = mode->crtc_vblank_end;
+
+ if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
+ vbl_start = DIV_ROUND_UP(vbl_start, 2);
+ vbl_end /= 2;
+ vtotal /= 2;
+ }
+
+ /*
+ * Lock uncore.lock, as we will do multiple timing critical raw
+ * register reads, potentially with preemption disabled, so the
+ * following code must not block on uncore.lock.
+ */
+ spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+ /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+
+ /* Get optional system timestamp before query. */
+ if (stime)
+ *stime = ktime_get();
+
+ if (crtc->mode_flags & I915_MODE_FLAG_VRR) {
+ int scanlines = intel_crtc_scanlines_since_frame_timestamp(crtc);
+
+ position = __intel_get_crtc_scanline(crtc);
+
+ /*
+ * Already exiting vblank? If so, shift our position
+ * so it looks like we're already apporaching the full
+ * vblank end. This should make the generated timestamp
+ * more or less match when the active portion will start.
+ */
+ if (position >= vbl_start && scanlines < position)
+ position = min(crtc->vmax_vblank_start + scanlines, vtotal - 1);
+ } else if (use_scanline_counter) {
+ /* No obvious pixelcount register. Only query vertical
+ * scanout position from Display scan line register.
+ */
+ position = __intel_get_crtc_scanline(crtc);
+ } else {
+ /*
+ * Have access to pixelcount since start of frame.
+ * We can split this into vertical and horizontal
+ * scanout position.
+ */
+ position = (intel_de_read_fw(dev_priv, PIPEFRAMEPIXEL(pipe)) & PIPE_PIXEL_MASK) >> PIPE_PIXEL_SHIFT;
+
+ /* convert to pixel counts */
+ vbl_start *= htotal;
+ vbl_end *= htotal;
+ vtotal *= htotal;
+
+ /*
+ * In interlaced modes, the pixel counter counts all pixels,
+ * so one field will have htotal more pixels. In order to avoid
+ * the reported position from jumping backwards when the pixel
+ * counter is beyond the length of the shorter field, just
+ * clamp the position the length of the shorter field. This
+ * matches how the scanline counter based position works since
+ * the scanline counter doesn't count the two half lines.
+ */
+ if (position >= vtotal)
+ position = vtotal - 1;
+
+ /*
+ * Start of vblank interrupt is triggered at start of hsync,
+ * just prior to the first active line of vblank. However we
+ * consider lines to start at the leading edge of horizontal
+ * active. So, should we get here before we've crossed into
+ * the horizontal active of the first line in vblank, we would
+ * not set the DRM_SCANOUTPOS_INVBL flag. In order to fix that,
+ * always add htotal-hsync_start to the current pixel position.
+ */
+ position = (position + htotal - hsync_start) % vtotal;
+ }
+
+ /* Get optional system timestamp after query. */
+ if (etime)
+ *etime = ktime_get();
+
+ /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+
+ /*
+ * While in vblank, position will be negative
+ * counting up towards 0 at vbl_end. And outside
+ * vblank, position will be positive counting
+ * up since vbl_end.
+ */
+ if (position >= vbl_start)
+ position -= vbl_end;
+ else
+ position += vtotal - vbl_end;
+
+ if (use_scanline_counter) {
+ *vpos = position;
+ *hpos = 0;
+ } else {
+ *vpos = position / htotal;
+ *hpos = position - (*vpos * htotal);
+ }
+
+ return true;
+}
+
+bool intel_crtc_get_vblank_timestamp(struct drm_crtc *crtc, int *max_error,
+ ktime_t *vblank_time, bool in_vblank_irq)
+{
+ return drm_crtc_vblank_helper_get_vblank_timestamp_internal(
+ crtc, max_error, vblank_time, in_vblank_irq,
+ i915_get_crtc_scanoutpos);
+}
+
+int intel_get_crtc_scanline(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ unsigned long irqflags;
+ int position;
+
+ spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ position = __intel_get_crtc_scanline(crtc);
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+
+ return position;
+}
diff --git a/drivers/gpu/drm/i915/display/intel_vblank.h b/drivers/gpu/drm/i915/display/intel_vblank.h
new file mode 100644
index 000000000000..c68eda6488bf
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_vblank.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2022-2023 Intel Corporation
+ */
+
+#ifndef __INTEL_VBLANK_H__
+#define __INTEL_VBLANK_H__
+
+#include <linux/ktime.h>
+#include <linux/types.h>
+
+struct drm_crtc;
+struct intel_crtc;
+
+u32 i915_get_vblank_counter(struct drm_crtc *crtc);
+u32 g4x_get_vblank_counter(struct drm_crtc *crtc);
+bool intel_crtc_get_vblank_timestamp(struct drm_crtc *crtc, int *max_error,
+ ktime_t *vblank_time, bool in_vblank_irq);
+int intel_get_crtc_scanline(struct intel_crtc *crtc);
+
+#endif /* __INTEL_VBLANK_H__ */
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 54ea28cf8a1a..240d5e198904 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -614,414 +614,6 @@ static void i915_enable_asle_pipestat(struct drm_i915_private *dev_priv)
spin_unlock_irq(&dev_priv->irq_lock);
}
-/*
- * This timing diagram depicts the video signal in and
- * around the vertical blanking period.
- *
- * Assumptions about the fictitious mode used in this example:
- * vblank_start >= 3
- * vsync_start = vblank_start + 1
- * vsync_end = vblank_start + 2
- * vtotal = vblank_start + 3
- *
- * start of vblank:
- * latch double buffered registers
- * increment frame counter (ctg+)
- * generate start of vblank interrupt (gen4+)
- * |
- * | frame start:
- * | generate frame start interrupt (aka. vblank interrupt) (gmch)
- * | may be shifted forward 1-3 extra lines via PIPECONF
- * | |
- * | | start of vsync:
- * | | generate vsync interrupt
- * | | |
- * ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx___ ___xxxx
- * . \hs/ . \hs/ \hs/ \hs/ . \hs/
- * ----va---> <-----------------vb--------------------> <--------va-------------
- * | | <----vs-----> |
- * -vbs-----> <---vbs+1---> <---vbs+2---> <-----0-----> <-----1-----> <-----2--- (scanline counter gen2)
- * -vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2---> <-----0--- (scanline counter gen3+)
- * -vbs-2---> <---vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2- (scanline counter hsw+ hdmi)
- * | | |
- * last visible pixel first visible pixel
- * | increment frame counter (gen3/4)
- * pixel counter = vblank_start * htotal pixel counter = 0 (gen3/4)
- *
- * x = horizontal active
- * _ = horizontal blanking
- * hs = horizontal sync
- * va = vertical active
- * vb = vertical blanking
- * vs = vertical sync
- * vbs = vblank_start (number)
- *
- * Summary:
- * - most events happen at the start of horizontal sync
- * - frame start happens at the start of horizontal blank, 1-4 lines
- * (depending on PIPECONF settings) after the start of vblank
- * - gen3/4 pixel and frame counter are synchronized with the start
- * of horizontal active on the first line of vertical active
- */
-
-/* Called from drm generic code, passed a 'crtc', which
- * we use as a pipe index
- */
-u32 i915_get_vblank_counter(struct drm_crtc *crtc)
-{
- struct drm_i915_private *dev_priv = to_i915(crtc->dev);
- struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[drm_crtc_index(crtc)];
- const struct drm_display_mode *mode = &vblank->hwmode;
- enum pipe pipe = to_intel_crtc(crtc)->pipe;
- i915_reg_t high_frame, low_frame;
- u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
- unsigned long irqflags;
-
- /*
- * On i965gm TV output the frame counter only works up to
- * the point when we enable the TV encoder. After that the
- * frame counter ceases to work and reads zero. We need a
- * vblank wait before enabling the TV encoder and so we
- * have to enable vblank interrupts while the frame counter
- * is still in a working state. However the core vblank code
- * does not like us returning non-zero frame counter values
- * when we've told it that we don't have a working frame
- * counter. Thus we must stop non-zero values leaking out.
- */
- if (!vblank->max_vblank_count)
- return 0;
-
- htotal = mode->crtc_htotal;
- hsync_start = mode->crtc_hsync_start;
- vbl_start = mode->crtc_vblank_start;
- if (mode->flags & DRM_MODE_FLAG_INTERLACE)
- vbl_start = DIV_ROUND_UP(vbl_start, 2);
-
- /* Convert to pixel count */
- vbl_start *= htotal;
-
- /* 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 & low register fields aren't synchronized, so make sure
- * we get a low value that's stable across two reads of the high
- * register.
- */
- do {
- high1 = intel_de_read_fw(dev_priv, high_frame) & PIPE_FRAME_HIGH_MASK;
- low = intel_de_read_fw(dev_priv, low_frame);
- high2 = intel_de_read_fw(dev_priv, 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;
-
- /*
- * The frame counter increments at beginning of active.
- * Cook up a vblank counter by also checking the pixel
- * counter against vblank start.
- */
- return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff;
-}
-
-u32 g4x_get_vblank_counter(struct drm_crtc *crtc)
-{
- struct drm_i915_private *dev_priv = to_i915(crtc->dev);
- struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[drm_crtc_index(crtc)];
- enum pipe pipe = to_intel_crtc(crtc)->pipe;
-
- if (!vblank->max_vblank_count)
- return 0;
-
- return intel_uncore_read(&dev_priv->uncore, PIPE_FRMCOUNT_G4X(pipe));
-}
-
-static u32 intel_crtc_scanlines_since_frame_timestamp(struct intel_crtc *crtc)
-{
- struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
- struct drm_vblank_crtc *vblank =
- &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
- const struct drm_display_mode *mode = &vblank->hwmode;
- u32 htotal = mode->crtc_htotal;
- u32 clock = mode->crtc_clock;
- u32 scan_prev_time, scan_curr_time, scan_post_time;
-
- /*
- * To avoid the race condition where we might cross into the
- * next vblank just between the PIPE_FRMTMSTMP and TIMESTAMP_CTR
- * reads. We make sure we read PIPE_FRMTMSTMP and TIMESTAMP_CTR
- * during the same frame.
- */
- do {
- /*
- * This field provides read back of the display
- * pipe frame time stamp. The time stamp value
- * is sampled at every start of vertical blank.
- */
- scan_prev_time = intel_de_read_fw(dev_priv,
- PIPE_FRMTMSTMP(crtc->pipe));
-
- /*
- * The TIMESTAMP_CTR register has the current
- * time stamp value.
- */
- scan_curr_time = intel_de_read_fw(dev_priv, IVB_TIMESTAMP_CTR);
-
- scan_post_time = intel_de_read_fw(dev_priv,
- PIPE_FRMTMSTMP(crtc->pipe));
- } while (scan_post_time != scan_prev_time);
-
- return div_u64(mul_u32_u32(scan_curr_time - scan_prev_time,
- clock), 1000 * htotal);
-}
-
-/*
- * On certain encoders on certain platforms, pipe
- * scanline register will not work to get the scanline,
- * since the timings are driven from the PORT or issues
- * with scanline register updates.
- * This function will use Framestamp and current
- * timestamp registers to calculate the scanline.
- */
-static u32 __intel_get_crtc_scanline_from_timestamp(struct intel_crtc *crtc)
-{
- struct drm_vblank_crtc *vblank =
- &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
- const struct drm_display_mode *mode = &vblank->hwmode;
- u32 vblank_start = mode->crtc_vblank_start;
- u32 vtotal = mode->crtc_vtotal;
- u32 scanline;
-
- scanline = intel_crtc_scanlines_since_frame_timestamp(crtc);
- scanline = min(scanline, vtotal - 1);
- scanline = (scanline + vblank_start) % vtotal;
-
- return scanline;
-}
-
-/*
- * intel_de_read_fw(), only for fast reads of display block, no need for
- * forcewake etc.
- */
-static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
-{
- struct drm_device *dev = crtc->base.dev;
- struct drm_i915_private *dev_priv = to_i915(dev);
- const struct drm_display_mode *mode;
- struct drm_vblank_crtc *vblank;
- enum pipe pipe = crtc->pipe;
- int position, vtotal;
-
- if (!crtc->active)
- return 0;
-
- vblank = &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
- mode = &vblank->hwmode;
-
- if (crtc->mode_flags & I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP)
- return __intel_get_crtc_scanline_from_timestamp(crtc);
-
- vtotal = mode->crtc_vtotal;
- if (mode->flags & DRM_MODE_FLAG_INTERLACE)
- vtotal /= 2;
-
- position = intel_de_read_fw(dev_priv, PIPEDSL(pipe)) & PIPEDSL_LINE_MASK;
-
- /*
- * On HSW, the DSL reg (0x70000) appears to return 0 if we
- * read it just before the start of vblank. So try it again
- * so we don't accidentally end up spanning a vblank frame
- * increment, causing the pipe_update_end() code to squak at us.
- *
- * The nature of this problem means we can't simply check the ISR
- * bit and return the vblank start value; nor can we use the scanline
- * debug register in the transcoder as it appears to have the same
- * problem. We may need to extend this to include other platforms,
- * but so far testing only shows the problem on HSW.
- */
- if (HAS_DDI(dev_priv) && !position) {
- int i, temp;
-
- for (i = 0; i < 100; i++) {
- udelay(1);
- temp = intel_de_read_fw(dev_priv, PIPEDSL(pipe)) & PIPEDSL_LINE_MASK;
- if (temp != position) {
- position = temp;
- break;
- }
- }
- }
-
- /*
- * See update_scanline_offset() for the details on the
- * scanline_offset adjustment.
- */
- return (position + crtc->scanline_offset) % vtotal;
-}
-
-static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
- bool in_vblank_irq,
- int *vpos, int *hpos,
- ktime_t *stime, ktime_t *etime,
- const struct drm_display_mode *mode)
-{
- struct drm_device *dev = _crtc->dev;
- struct drm_i915_private *dev_priv = to_i915(dev);
- struct intel_crtc *crtc = to_intel_crtc(_crtc);
- enum pipe pipe = crtc->pipe;
- int position;
- int vbl_start, vbl_end, hsync_start, htotal, vtotal;
- unsigned long irqflags;
- bool use_scanline_counter = DISPLAY_VER(dev_priv) >= 5 ||
- IS_G4X(dev_priv) || DISPLAY_VER(dev_priv) == 2 ||
- crtc->mode_flags & I915_MODE_FLAG_USE_SCANLINE_COUNTER;
-
- if (drm_WARN_ON(&dev_priv->drm, !mode->crtc_clock)) {
- drm_dbg(&dev_priv->drm,
- "trying to get scanoutpos for disabled "
- "pipe %c\n", pipe_name(pipe));
- return false;
- }
-
- htotal = mode->crtc_htotal;
- hsync_start = mode->crtc_hsync_start;
- vtotal = mode->crtc_vtotal;
- vbl_start = mode->crtc_vblank_start;
- vbl_end = mode->crtc_vblank_end;
-
- if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
- vbl_start = DIV_ROUND_UP(vbl_start, 2);
- vbl_end /= 2;
- vtotal /= 2;
- }
-
- /*
- * Lock uncore.lock, as we will do multiple timing critical raw
- * register reads, potentially with preemption disabled, so the
- * following code must not block on uncore.lock.
- */
- spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
-
- /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
-
- /* Get optional system timestamp before query. */
- if (stime)
- *stime = ktime_get();
-
- if (crtc->mode_flags & I915_MODE_FLAG_VRR) {
- int scanlines = intel_crtc_scanlines_since_frame_timestamp(crtc);
-
- position = __intel_get_crtc_scanline(crtc);
-
- /*
- * Already exiting vblank? If so, shift our position
- * so it looks like we're already apporaching the full
- * vblank end. This should make the generated timestamp
- * more or less match when the active portion will start.
- */
- if (position >= vbl_start && scanlines < position)
- position = min(crtc->vmax_vblank_start + scanlines, vtotal - 1);
- } else if (use_scanline_counter) {
- /* No obvious pixelcount register. Only query vertical
- * scanout position from Display scan line register.
- */
- position = __intel_get_crtc_scanline(crtc);
- } else {
- /* Have access to pixelcount since start of frame.
- * We can split this into vertical and horizontal
- * scanout position.
- */
- position = (intel_de_read_fw(dev_priv, PIPEFRAMEPIXEL(pipe)) & PIPE_PIXEL_MASK) >> PIPE_PIXEL_SHIFT;
-
- /* convert to pixel counts */
- vbl_start *= htotal;
- vbl_end *= htotal;
- vtotal *= htotal;
-
- /*
- * In interlaced modes, the pixel counter counts all pixels,
- * so one field will have htotal more pixels. In order to avoid
- * the reported position from jumping backwards when the pixel
- * counter is beyond the length of the shorter field, just
- * clamp the position the length of the shorter field. This
- * matches how the scanline counter based position works since
- * the scanline counter doesn't count the two half lines.
- */
- if (position >= vtotal)
- position = vtotal - 1;
-
- /*
- * Start of vblank interrupt is triggered at start of hsync,
- * just prior to the first active line of vblank. However we
- * consider lines to start at the leading edge of horizontal
- * active. So, should we get here before we've crossed into
- * the horizontal active of the first line in vblank, we would
- * not set the DRM_SCANOUTPOS_INVBL flag. In order to fix that,
- * always add htotal-hsync_start to the current pixel position.
- */
- position = (position + htotal - hsync_start) % vtotal;
- }
-
- /* Get optional system timestamp after query. */
- if (etime)
- *etime = ktime_get();
-
- /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
-
- spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
-
- /*
- * While in vblank, position will be negative
- * counting up towards 0 at vbl_end. And outside
- * vblank, position will be positive counting
- * up since vbl_end.
- */
- if (position >= vbl_start)
- position -= vbl_end;
- else
- position += vtotal - vbl_end;
-
- if (use_scanline_counter) {
- *vpos = position;
- *hpos = 0;
- } else {
- *vpos = position / htotal;
- *hpos = position - (*vpos * htotal);
- }
-
- return true;
-}
-
-bool intel_crtc_get_vblank_timestamp(struct drm_crtc *crtc, int *max_error,
- ktime_t *vblank_time, bool in_vblank_irq)
-{
- return drm_crtc_vblank_helper_get_vblank_timestamp_internal(
- crtc, max_error, vblank_time, in_vblank_irq,
- i915_get_crtc_scanoutpos);
-}
-
-int intel_get_crtc_scanline(struct intel_crtc *crtc)
-{
- struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
- unsigned long irqflags;
- int position;
-
- spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
- position = __intel_get_crtc_scanline(crtc);
- spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
-
- return position;
-}
-
/**
* ivb_parity_work - Workqueue called when a parity error interrupt
* occurred.
diff --git a/drivers/gpu/drm/i915/i915_irq.h b/drivers/gpu/drm/i915/i915_irq.h
index 9b004fc3444e..03ee4c8b1ed3 100644
--- a/drivers/gpu/drm/i915/i915_irq.h
+++ b/drivers/gpu/drm/i915/i915_irq.h
@@ -66,18 +66,12 @@ bool intel_irqs_enabled(struct drm_i915_private *dev_priv);
void intel_synchronize_irq(struct drm_i915_private *i915);
void intel_synchronize_hardirq(struct drm_i915_private *i915);
-int intel_get_crtc_scanline(struct intel_crtc *crtc);
void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
u8 pipe_mask);
void gen8_irq_power_well_pre_disable(struct drm_i915_private *dev_priv,
u8 pipe_mask);
u32 gen8_de_pipe_underrun_mask(struct drm_i915_private *dev_priv);
-bool intel_crtc_get_vblank_timestamp(struct drm_crtc *crtc, int *max_error,
- ktime_t *vblank_time, bool in_vblank_irq);
-
-u32 i915_get_vblank_counter(struct drm_crtc *crtc);
-u32 g4x_get_vblank_counter(struct drm_crtc *crtc);
int i8xx_enable_vblank(struct drm_crtc *crtc);
int i915gm_enable_vblank(struct drm_crtc *crtc);
--
2.34.1
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