On Thu, Jun 10, 2021 at 04:09:19PM +0100, Paul Cercueil wrote:
Hi Daniel,
Le mar., juin 1 2021 at 17:48:12 +0200, Daniel Vetter daniel@ffwll.ch a écrit :
On Fri, May 28, 2021 at 12:20:58AM +0100, Paul Cercueil wrote:
This information is carried from the ".atomic_check" to the ".atomic_commit_tail"; as such it is state-specific, and should be moved to the private state structure.
Signed-off-by: Paul Cercueil paul@crapouillou.net
Not sure this applies to your hw, but drm_crtc_state.no_vblank exists. Might want to move to that instead of rolling your own. Or explain why you need your own here in your own private state. It does look quite a bit like you're just rolling your own version of this support that helpers gained meanwhile.
If I use drm_crtc_state->no_vblank, then I need a custom .atomic_commit_tail() that only calls drm_atomic_helper_wait_for_vblanks() when !no_vblank. That works, but I don't understand why drm_atomic_helper_commit_tail() doesn't do that by default, and makes me think I'm using it wrong.
So the recommendation is to have your own commit_tail and use drm_atomic_helper_wait_for_flip_done(). But also if wait_for_vblanks dies on you, there's a driver bug: If vblanks arent available, then the drm_crtc_vblank_get should fail. If that's not the case then I guess some bigger issues to be fixed because userspace might also do a vblank wait (for timing the next frame), so that really needs to work correctly.
That's kinda why I put that wait_for_vblank in there by default, it forces drivers to be correct.
If you're wondering how that's done: This is why the driver ->enable_vblank callback can return an error code. So maybe the real fix here is in there, and everything else can stay as-is?
Another thing is that if you call drm_crtc_vblank_on/off correctly, this should also work out correctly - attempted vblank waits outside of when the vblank is running should fail.
Maybe something fell off here in this area because it's tricky, but the infrastructure should be here already. -Daniel
Cheers, -Paul
-Daniel
drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 41 ++++++++++++++++++++--- 1 file changed, 37 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c index e81084eb3b0e..639994329c60 100644 --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c @@ -66,6 +66,8 @@ struct jz_soc_info {
struct ingenic_drm_private_state { struct drm_private_state base;
- bool no_vblank;
};
struct ingenic_drm { @@ -87,7 +89,6 @@ struct ingenic_drm { dma_addr_t dma_hwdescs_phys;
bool panel_is_sharp;
bool no_vblank;
/*
- clk_mutex is used to synchronize the pixel clock rate update
with @@ -113,6 +114,30 @@ to_ingenic_drm_priv_state(struct drm_private_state *state) return container_of(state, struct ingenic_drm_private_state, base); }
+static struct ingenic_drm_private_state * +ingenic_drm_get_priv_state(struct ingenic_drm *priv, struct drm_atomic_state *state) +{
- struct drm_private_state *priv_state;
- priv_state = drm_atomic_get_private_obj_state(state,
&priv->private_obj);
- if (IS_ERR(priv_state))
return ERR_CAST(priv_state);- return to_ingenic_drm_priv_state(priv_state);
+}
+static struct ingenic_drm_private_state * +ingenic_drm_get_new_priv_state(struct ingenic_drm *priv, struct drm_atomic_state *state) +{
- struct drm_private_state *priv_state;
- priv_state = drm_atomic_get_new_private_obj_state(state,
&priv->private_obj);
- if (!priv_state)
return NULL;- return to_ingenic_drm_priv_state(priv_state);
+}
static bool ingenic_drm_writeable_reg(struct device *dev, unsigned int reg) { switch (reg) { @@ -268,6 +293,7 @@ static int ingenic_drm_crtc_atomic_check(struct drm_crtc *crtc, crtc); struct ingenic_drm *priv = drm_crtc_get_priv(crtc); struct drm_plane_state *f1_state, *f0_state, *ipu_state = NULL;
struct ingenic_drm_private_state *priv_state;
if (crtc_state->gamma_lut && drm_color_lut_size(crtc_state->gamma_lut) !=
ARRAY_SIZE(priv->dma_hwdescs->palette)) { @@ -299,9 +325,13 @@ static int ingenic_drm_crtc_atomic_check(struct drm_crtc *crtc, } }
priv_state = ingenic_drm_get_priv_state(priv, state);if (IS_ERR(priv_state))return PTR_ERR(priv_state);- /* If all the planes are disabled, we won't get a VBLANK IRQ */
priv->no_vblank = !f1_state->fb && !f0_state->fb &&!(ipu_state && ipu_state->fb);
priv_state->no_vblank = !f1_state->fb && !f0_state->fb &&!(ipu_state && ipu_state->fb);}
return 0;
@@ -727,6 +757,7 @@ static void ingenic_drm_atomic_helper_commit_tail(struct drm_atomic_state *old_s */ struct drm_device *dev = old_state->dev; struct ingenic_drm *priv = drm_device_get_priv(dev);
struct ingenic_drm_private_state *priv_state;
drm_atomic_helper_commit_modeset_disables(dev, old_state);
@@ -736,7 +767,9 @@ static void ingenic_drm_atomic_helper_commit_tail(struct drm_atomic_state *old_s
drm_atomic_helper_commit_hw_done(old_state);
- if (!priv->no_vblank)
priv_state = ingenic_drm_get_new_priv_state(priv, old_state);
if (!priv_state || !priv_state->no_vblank) drm_atomic_helper_wait_for_vblanks(dev, old_state);
drm_atomic_helper_cleanup_planes(dev, old_state);
-- 2.30.2
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch