vtimofei
/
smithay
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

drm: Add more inline comments explaining the drm code

This commit is contained in:
Drakulix 2017-09-14 22:27:35 +02:00
parent 7bf4105050
commit 9c71793b0e
1 changed files with 32 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
src/backend/drm/backend.rs
View File

@ -111,6 +111,7 @@ impl DrmBackendInternal {
let connectors = connectors.into();
// check the connectors, if they suite the mode
for connector in connectors.iter() {
if !connector::Info::load_from_device(context.head().head(), *connector)?
.modes()
@ -122,7 +123,7 @@ impl DrmBackendInternal {
let (w, h) = mode.size();
info!(log, "Drm Backend initialized");
info!(log, "Drm Backend initializing");
Ok(DrmBackendInternal {
graphics: Graphics::try_new(context, |context| {
@ -139,6 +140,7 @@ impl DrmBackendInternal {
)?
},
surface: Surface::try_new(
// create a gbm surface
Box::new(context.devices.gbm.create_surface(
w as u32,
h as u32,
@ -146,12 +148,18 @@ impl DrmBackendInternal {
&[BufferObjectFlags::Scanout, BufferObjectFlags::Rendering],
)?),
|surface| {
// create an egl surface from the gbm one
let egl_surface = context.egl.create_surface(&surface)?;
// set it to be able to use `crtc::set` once
unsafe { egl_surface.make_current()? };
egl_surface.swap_buffers()?;
// init the first screen
// (must be done before calling page_flip for the first time)
let mut front_bo = surface.lock_front_buffer()?;
debug!(log, "FrontBuffer color format: {:?}", front_bo.format());
// we need a framebuffer per front buffer
let fb = framebuffer::create(context.devices.drm, &*front_bo)?;
crtc::set(
context.devices.drm,
@ -183,6 +191,8 @@ impl DrmBackendInternal {
}
pub(crate) fn unlock_buffer(&self) {
// after the page swap is finished we need to release the rendered buffer.
// this is called from the PageFlipHandler
self.graphics.rent(|gbm| {
gbm.surface.rent(|egl| {
let next_bo = egl.buffers.next_buffer.replace(None);
@ -212,6 +222,8 @@ impl DrmBackend {
let info =
connector::Info::load_from_device(self.0.borrow().graphics.head().head().head(), connector)
.map_err(|err| ModeError::FailedToLoad(err))?;
// check if the connector can handle the current mode
let mut internal = self.0.borrow_mut();
if info.modes().contains(&internal.mode) {
internal.connectors.push(connector);
@ -223,6 +235,7 @@ impl DrmBackend {
/// Returns a copy of the currently set connectors
pub fn used_connectors(&self) -> Vec<connector::Handle> {
// thanks to the RefCell we can sadly not return a `&[connector::Handle]`
self.0.borrow().connectors.clone()
}
@ -239,6 +252,7 @@ impl DrmBackend {
/// Several internal resources will need to be recreated to fit the new `Mode`.
/// Other errors might occur.
pub fn use_mode(&mut self, mode: Mode) -> Result<(), DrmError> {
// check the connectors
for connector in self.0.borrow().connectors.iter() {
if !connector::Info::load_from_device(self.0.borrow().graphics.head().head().head(), *connector)?
.modes()
@ -248,6 +262,8 @@ impl DrmBackend {
}
}
// borrow & clone stuff because rust cannot figure out the upcoming
// closure otherwise.
let crtc = self.0.borrow().crtc;
let mut internal = self.0.borrow_mut();
let connectors = internal.connectors.clone();
@ -258,6 +274,8 @@ impl DrmBackend {
internal
.graphics
.rent_all_mut(|graphics| -> Result<(), DrmError> {
// Recreate the surface and the related resources to match the new
// resolution.
graphics.gbm.surface = Surface::try_new(
Box::new(graphics.context.devices.gbm.create_surface(
w as u32,
@ -267,12 +285,17 @@ impl DrmBackend {
)?),
|surface| {
let egl_surface = graphics.context.egl.create_surface(&surface)?;
// make it active for the first crtc::set
// (which is needed before the first page_flip)
unsafe { egl_surface.make_current()? };
egl_surface.swap_buffers()?;
let mut front_bo = surface.lock_front_buffer()?;
debug!(logger, "FrontBuffer color format: {:?}", front_bo.format());
// we need a framebuffer per front_buffer
let fb = framebuffer::create(graphics.context.devices.drm, &*front_bo)?;
// init the first screen
crtc::set(
graphics.context.devices.drm,
crtc,
@ -324,6 +347,7 @@ impl GraphicsBackend for DrmBackend {
fn set_cursor_representation(&self, buffer: ImageBuffer<Rgba<u8>, Vec<u8>>, hotspot: (u32, u32))
-> Result<(), DrmError> {
let (w, h) = buffer.dimensions();
/// import the cursor into a buffer we can render
self.0
.borrow_mut()
.graphics
@ -341,6 +365,7 @@ impl GraphicsBackend for DrmBackend {
Ok(())
})?;
// and set it
if crtc::set_cursor2(
self.0.borrow().graphics.head().head().head(),
self.0.borrow().crtc,
@ -380,14 +405,18 @@ impl EGLGraphicsBackend for DrmBackend {
return Err(SwapBuffersError::AlreadySwapped);
}
/// flip normally
graphics.gbm.surface.rent(|egl| egl.surface.swap_buffers())?;
graphics.gbm.surface.rent_all(|surface| {
// supporting this would cause a lot of inconvinience and
// supporting this error would cause a lot of inconvinience and
// would most likely result in a lot of flickering.
// neither weston, wlc or wlroots bother with that as well.
// so we just assume we got at least two buffers to do flipping
let mut next_bo = surface.gbm.lock_front_buffer().expect("Surface only has one front buffer. Not supported by smithay");
// create a framebuffer if the front buffer does not have one already
// (they are reused by gbm)
let maybe_fb = next_bo.userdata().cloned();
let fb = if let Some(info) = maybe_fb {
info
@ -402,6 +431,7 @@ impl EGLGraphicsBackend for DrmBackend {
let id: Id = self.0.borrow().own_id;
// and flip
crtc::page_flip(graphics.context.devices.drm, self.0.borrow().crtc, fb.handle(), &[crtc::PageFlipFlags::PageFlipEvent], id).map_err(|_| SwapBuffersError::ContextLost)
})
})