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authorThomas Zimmermann <tzimmermann@suse.de>2020-01-23 14:59:23 +0100
committerThomas Zimmermann <tzimmermann@suse.de>2020-02-13 13:08:13 +0100
commitf1e2b6371c12aec5e772e5fdedaa4455c20a787f (patch)
tree10b7d59c36576348f8733c868377d87bddbdcc12 /drivers/gpu/drm/drm_vblank.c
parent9e0e8f01c862a3eb4599452aa576620be8f01e94 (diff)
drm: Add get_scanout_position() to struct drm_crtc_helper_funcs
The new callback get_scanout_position() reads the current location of the scanout process. The operation is currently located in struct drm_driver, but really belongs to the CRTC. Drivers will be converted in separate patches. To help with the conversion, the timestamp calculation has been moved from drm_calc_vbltimestamp_from_scanoutpos() to drm_crtc_vblank_helper_get_vblank_timestamp_internal(). The helper function supports the new and old interface of get_scanout_position(). drm_calc_vbltimestamp_from_scanoutpos() remains as a wrapper around the new function. Callback functions return the scanout position from the CRTC. The legacy version of the interface receives the device and pipe index, the modern version receives a pointer to the CRTC. We keep the legacy version until all drivers have been converted. v4: * 80-character line fixes v3: * refactor drm_calc_vbltimestamp_from_scanoutpos() to minimize code duplication * define types for get_scanout_position() callbacks v2: * fix logical op in drm_calc_vbltimestamp_from_scanoutpos() Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Tested-by: Yannick Fertré <yannick.fertre@st.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-3-tzimmermann@suse.de
Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
-rw-r--r--drivers/gpu/drm/drm_vblank.c101
1 files changed, 83 insertions, 18 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index d7f5d4023f50..496395324d1f 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -30,6 +30,7 @@
#include <drm/drm_crtc.h>
#include <drm/drm_drv.h>
#include <drm/drm_framebuffer.h>
+#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_vblank.h>
@@ -605,7 +606,7 @@ EXPORT_SYMBOL(drm_calc_timestamping_constants);
* Implements calculation of exact vblank timestamps from given drm_display_mode
* timings and current video scanout position of a CRTC. This can be directly
* used as the &drm_driver.get_vblank_timestamp implementation of a kms driver
- * if &drm_driver.get_scanout_position is implemented.
+ * if &drm_crtc_helper_funcs.get_scanout_position is implemented.
*
* The current implementation only handles standard video modes. For double scan
* and interlaced modes the driver is supposed to adjust the hardware mode
@@ -627,28 +628,85 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
ktime_t *vblank_time,
bool in_vblank_irq)
{
- struct timespec64 ts_etime, ts_vblank_time;
- ktime_t stime, etime;
- bool vbl_status;
struct drm_crtc *crtc;
- const struct drm_display_mode *mode;
- struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
- int vpos, hpos, i;
- int delta_ns, duration_ns;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return false;
crtc = drm_crtc_from_index(dev, pipe);
+ if (!crtc)
+ return false;
- if (pipe >= dev->num_crtcs || !crtc) {
+ return drm_crtc_vblank_helper_get_vblank_timestamp_internal(crtc,
+ max_error,
+ vblank_time,
+ in_vblank_irq,
+ crtc->helper_private->get_scanout_position,
+ dev->driver->get_scanout_position);
+}
+EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
+
+/**
+ * drm_crtc_vblank_helper_get_vblank_timestamp_internal - precise vblank
+ * timestamp helper
+ * @dev: DRM device
+ * @pipe: index of CRTC whose vblank timestamp to retrieve
+ * @max_error: Desired maximum allowable error in timestamps (nanosecs)
+ * On return contains true maximum error of timestamp
+ * @vblank_time: Pointer to time which should receive the timestamp
+ * @in_vblank_irq:
+ * True when called from drm_crtc_handle_vblank(). Some drivers
+ * need to apply some workarounds for gpu-specific vblank irq quirks
+ * if flag is set.
+ * @get_scanout_position:
+ * Callback function to retrieve the scanout position. See
+ * @struct drm_crtc_helper_funcs.get_scanout_position.
+ * @get_scanout_position_legacy:
+ * Callback function to retrieve the scanout position. See
+ * @struct drm_driver.get_scanout_position.
+ *
+ * Implements calculation of exact vblank timestamps from given drm_display_mode
+ * timings and current video scanout position of a CRTC.
+ *
+ * The current implementation only handles standard video modes. For double scan
+ * and interlaced modes the driver is supposed to adjust the hardware mode
+ * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to
+ * match the scanout position reported.
+ *
+ * Note that atomic drivers must call drm_calc_timestamping_constants() before
+ * enabling a CRTC. The atomic helpers already take care of that in
+ * drm_atomic_helper_update_legacy_modeset_state().
+ *
+ * Returns:
+ *
+ * Returns true on success, and false on failure, i.e. when no accurate
+ * timestamp could be acquired.
+ */
+bool
+drm_crtc_vblank_helper_get_vblank_timestamp_internal(
+ struct drm_crtc *crtc, int *max_error, ktime_t *vblank_time,
+ bool in_vblank_irq,
+ drm_vblank_get_scanout_position_func get_scanout_position,
+ drm_vblank_get_scanout_position_legacy_func get_scanout_position_legacy)
+{
+ struct drm_device *dev = crtc->dev;
+ unsigned int pipe = crtc->index;
+ struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
+ struct timespec64 ts_etime, ts_vblank_time;
+ ktime_t stime, etime;
+ bool vbl_status;
+ const struct drm_display_mode *mode;
+ int vpos, hpos, i;
+ int delta_ns, duration_ns;
+
+ if (pipe >= dev->num_crtcs) {
DRM_ERROR("Invalid crtc %u\n", pipe);
return false;
}
/* Scanout position query not supported? Should not happen. */
- if (!dev->driver->get_scanout_position) {
- DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
+ if (!get_scanout_position && !get_scanout_position_legacy) {
+ DRM_ERROR("Called from CRTC w/o get_scanout_position()!?\n");
return false;
}
@@ -663,7 +721,6 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
if (mode->crtc_clock == 0) {
DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev));
-
return false;
}
@@ -679,11 +736,19 @@ bool 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,
- in_vblank_irq,
- &vpos, &hpos,
- &stime, &etime,
- mode);
+ if (get_scanout_position) {
+ vbl_status = get_scanout_position(crtc,
+ in_vblank_irq,
+ &vpos, &hpos,
+ &stime, &etime,
+ mode);
+ } else {
+ vbl_status = get_scanout_position_legacy(dev, pipe,
+ in_vblank_irq,
+ &vpos, &hpos,
+ &stime, &etime,
+ mode);
+ }
/* Return as no-op if scanout query unsupported or failed. */
if (!vbl_status) {
@@ -735,7 +800,7 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
return true;
}
-EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
+EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp_internal);
/**
* drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent