From 18c6a8ccaf6f17264f153440703cab9feae47988 Mon Sep 17 00:00:00 2001
From: Vaxry <vaxry@vaxry.net>
Date: Sat, 3 Aug 2024 18:23:19 +0200
Subject: [PATCH] drm: immediately send presentation events for tearing
---
src/backend/drm/DRM.cpp | 49 +++++++++++++++++++++++++++++++----------
1 file changed, 37 insertions(+), 12 deletions(-)
diff --git a/src/backend/drm/DRM.cpp b/src/backend/drm/DRM.cpp
index 16bab55..c56634c 100644
--- a/src/backend/drm/DRM.cpp
+++ b/src/backend/drm/DRM.cpp
@@ -139,18 +139,18 @@ static std::vector<SP<CSessionDevice>> scanGPUs(SP<CBackend> backend) {
// Iterate over GPUs and canonicalize the paths
for (auto& d : explicitDevices) {
- std::error_code ec;
-
- auto canonicalFilePath = std::filesystem::canonical(d, ec);
-
- // If there is an error, log and continue.
- // TODO: Verify that the path is a valid DRM device. (https://gitlab.freedesktop.org/wlroots/wlroots/-/blob/master/backend/session/session.c?ref_type=heads#L369-387)
- if (ec) {
- backend->log(AQ_LOG_ERROR, std::format("drm: Failed to canonicalize path {}", d));
- continue;
- }
+ std::error_code ec;
- d = canonicalFilePath.string();
+ auto canonicalFilePath = std::filesystem::canonical(d, ec);
+
+ // If there is an error, log and continue.
+ // TODO: Verify that the path is a valid DRM device. (https://gitlab.freedesktop.org/wlroots/wlroots/-/blob/master/backend/session/session.c?ref_type=heads#L369-387)
+ if (ec) {
+ backend->log(AQ_LOG_ERROR, std::format("drm: Failed to canonicalize path {}", d));
+ continue;
+ }
+
+ d = canonicalFilePath.string();
}
for (auto& d : explicitDevices) {
@@ -1436,8 +1436,10 @@ bool Aquamarine::CDRMOutput::commitState(bool onlyTest) {
if (STATE.enabled && (COMMITTED & COutputState::eOutputStateProperties::AQ_OUTPUT_STATE_BUFFER))
flags |= DRM_MODE_PAGE_FLIP_EVENT;
- if (STATE.presentationMode == AQ_OUTPUT_PRESENTATION_IMMEDIATE && (COMMITTED & COutputState::eOutputStateProperties::AQ_OUTPUT_STATE_BUFFER))
+ if (STATE.presentationMode == AQ_OUTPUT_PRESENTATION_IMMEDIATE && (COMMITTED & COutputState::eOutputStateProperties::AQ_OUTPUT_STATE_BUFFER)) {
flags |= DRM_MODE_PAGE_FLIP_ASYNC;
+ flags &= ~DRM_MODE_PAGE_FLIP_EVENT; // Do not request an event for immediate page flips, as it makes no sense.
+ }
}
// we can't go further without a blit
@@ -1505,6 +1507,7 @@ bool Aquamarine::CDRMOutput::commitState(bool onlyTest) {
fourccToName(STATE.drmFormat), fourccToName(params.format)));
state->setFormat(params.format);
formatMismatch = true;
+ // TODO: reject if tearing? We will miss a frame event!
flags &= ~DRM_MODE_PAGE_FLIP_ASYNC; // we cannot modeset with async pf
}
}
@@ -1560,6 +1563,28 @@ bool Aquamarine::CDRMOutput::commitState(bool onlyTest) {
if (ok)
connector->commitTainted = false;
+ if (data.flags & DRM_MODE_PAGE_FLIP_ASYNC) {
+ // for tearing commits, we will send presentation feedback instantly, and rotate
+ // drm framebuffers to properly send backendRelease events.
+ // the last FB should already be gone from KMS because it's been immediately replaced
+
+ // no completion and no vsync, because tearing
+ uint32_t flags = IOutput::AQ_OUTPUT_PRESENT_HW_CLOCK | IOutput::AQ_OUTPUT_PRESENT_ZEROCOPY;
+
+ timespec presented;
+ clock_gettime(CLOCK_MONOTONIC, &presented);
+
+ connector->output->events.present.emit(IOutput::SPresentEvent{
+ .presented = backend->sessionActive(),
+ .when = &presented,
+ .seq = 0, /* unknown sequence for tearing */
+ .refresh = (int)(connector->refresh ? (1000000000000LL / connector->refresh) : 0),
+ .flags = flags,
+ });
+
+ connector->onPresent();
+ }
+
return ok;
}