bcm27xx: add linux 5.4 support

Tested on bcm2710 (Raspberry Pi 3B).

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 100 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.4/950-0299-drm-vc4-Resolve-the-vblank-warnings-on-mode-switchin.patch b/target/linux/bcm27xx/patches-5.4/950-0299-drm-vc4-Resolve-the-vblank-warnings-on-mode-switchin.patch
new file mode 100644
index 0000000000..e50bdee8ae
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0299-drm-vc4-Resolve-the-vblank-warnings-on-mode-switchin.patch
@@ -0,0 +1,100 @@
+From a82d716ab4c2ab5f198f3461e32614defb52c724 Mon Sep 17 00:00:00 2001
+From: Dave Stevenson <dave.stevenson@raspberrypi.org>
+Date: Thu, 25 Jul 2019 17:27:44 +0100
+Subject: [PATCH] drm/vc4: Resolve the vblank warnings on mode
+ switching
+
+The details over when and how a driver is to service the
+vblank events are sketchy, and the fkms driver was triggering
+a kernel warning every time the crtc was enabled or disabled.
+
+Copy the event handling as used by the vc4-kms driver slightly
+more closely, and we avoid the warnings.
+
+https://github.com/raspberrypi/linux/issues/3020
+
+Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
+---
+ drivers/gpu/drm/vc4/vc4_firmware_kms.c | 48 ++++++++++++++++++--------
+ 1 file changed, 33 insertions(+), 15 deletions(-)
+
+--- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c
++++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c
+@@ -964,6 +964,7 @@ static void vc4_crtc_mode_set_nofb(struc
+ 
+ static void vc4_crtc_disable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)
+ {
++	struct drm_device *dev = crtc->dev;
+ 	struct drm_plane *plane;
+ 
+ 	DRM_DEBUG_KMS("[CRTC:%d] vblanks off.\n",
+@@ -979,6 +980,35 @@ static void vc4_crtc_disable(struct drm_
+ 
+ 	drm_atomic_crtc_for_each_plane(plane, crtc)
+ 		vc4_plane_atomic_disable(plane, plane->state);
++
++	/*
++	 * Make sure we issue a vblank event after disabling the CRTC if
++	 * someone was waiting it.
++	 */
++	if (crtc->state->event) {
++		unsigned long flags;
++
++		spin_lock_irqsave(&dev->event_lock, flags);
++		drm_crtc_send_vblank_event(crtc, crtc->state->event);
++		crtc->state->event = NULL;
++		spin_unlock_irqrestore(&dev->event_lock, flags);
++	}
++}
++
++static void vc4_crtc_consume_event(struct drm_crtc *crtc)
++{
++	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
++	struct drm_device *dev = crtc->dev;
++	unsigned long flags;
++
++	crtc->state->event->pipe = drm_crtc_index(crtc);
++
++	WARN_ON(drm_crtc_vblank_get(crtc) != 0);
++
++	spin_lock_irqsave(&dev->event_lock, flags);
++	vc4_crtc->event = crtc->state->event;
++	crtc->state->event = NULL;
++	spin_unlock_irqrestore(&dev->event_lock, flags);
+ }
+ 
+ static void vc4_crtc_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)
+@@ -988,6 +1018,7 @@ static void vc4_crtc_enable(struct drm_c
+ 	DRM_DEBUG_KMS("[CRTC:%d] vblanks on.\n",
+ 		      crtc->base.id);
+ 	drm_crtc_vblank_on(crtc);
++	vc4_crtc_consume_event(crtc);
+ 
+ 	/* Unblank the planes (if they're supposed to be displayed). */
+ 	drm_atomic_crtc_for_each_plane(plane, crtc)
+@@ -1059,23 +1090,10 @@ static int vc4_crtc_atomic_check(struct
+ static void vc4_crtc_atomic_flush(struct drm_crtc *crtc,
+ 				  struct drm_crtc_state *old_state)
+ {
+-	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+-	struct drm_device *dev = crtc->dev;
+-
+ 	DRM_DEBUG_KMS("[CRTC:%d] crtc_atomic_flush.\n",
+ 		      crtc->base.id);
+-	if (crtc->state->event) {
+-		unsigned long flags;
+-
+-		crtc->state->event->pipe = drm_crtc_index(crtc);
+-
+-		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+-
+-		spin_lock_irqsave(&dev->event_lock, flags);
+-		vc4_crtc->event = crtc->state->event;
+-		crtc->state->event = NULL;
+-		spin_unlock_irqrestore(&dev->event_lock, flags);
+-	}
++	if (crtc->state->active && old_state->active && crtc->state->event)
++		vc4_crtc_consume_event(crtc);
+ }
+ 
+ static void vc4_crtc_handle_page_flip(struct vc4_crtc *vc4_crtc)