Initial pass at porting MGA to vblank-rework

This is currently only compile tested.

2 files changed, 63 insertions, 27 deletions

diff --git a/shared-core/mga_drv.h b/shared-core/mga_drv.h
index bce82135..4764edab 100644
--- a/shared-core/mga_drv.h
+++ b/shared-core/mga_drv.h
@@ -113,13 +113,14 @@ typedef struct drm_mga_private {
 	 * \sa drm_mga_private_t::mmio
 	 */
 	/*@{*/
-	u32 mmio_base;             /**< Bus address of base of MMIO. */
-	u32 mmio_size;             /**< Size of the MMIO region. */
+	u32 mmio_base;			/**< Bus address of base of MMIO. */
+	u32 mmio_size;			/**< Size of the MMIO region. */
 	/*@}*/
 
 	u32 clear_cmd;
 	u32 maccess;
 
+	atomic_t vbl_received;		/**< Number of vblanks received. */
 	wait_queue_head_t fence_queue;
 	atomic_t last_fence_retired;
 	u32 next_fence_to_post;
@@ -177,10 +178,12 @@ extern int mga_warp_init(drm_mga_private_t * dev_priv);
 
 				/* mga_irq.c */
 extern int mga_driver_fence_wait(drm_device_t * dev, unsigned int *sequence);
-extern int mga_driver_vblank_wait(drm_device_t * dev, unsigned int *sequence);
+extern int mga_enable_vblank(drm_device_t *dev, int crtc);
+extern void mga_disable_vblank(drm_device_t *dev, int crtc);
+extern u32 mga_get_vblank_counter(drm_device_t *dev, int crtc);
 extern irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS);
 extern void mga_driver_irq_preinstall(drm_device_t * dev);
-extern void mga_driver_irq_postinstall(drm_device_t * dev);
+extern int mga_driver_irq_postinstall(drm_device_t * dev);
 extern void mga_driver_irq_uninstall(drm_device_t * dev);
 extern long mga_compat_ioctl(struct file *filp, unsigned int cmd,
 			     unsigned long arg);
diff --git a/shared-core/mga_irq.c b/shared-core/mga_irq.c
index 490d1fbb..a49a9b6e 100644
--- a/shared-core/mga_irq.c
+++ b/shared-core/mga_irq.c
@@ -36,6 +36,20 @@
 #include "mga_drm.h"
 #include "mga_drv.h"
 
+u32 mga_get_vblank_counter(drm_device_t *dev, int crtc)
+{
+	const drm_mga_private_t *const dev_priv = 
+		(drm_mga_private_t *) dev->dev_private;
+
+	if (crtc != 0) {
+		return 0;
+	}
+
+
+	return atomic_read(&dev_priv->vbl_received);
+}
+
+
 irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS)
 {
 	drm_device_t *dev = (drm_device_t *) arg;
@@ -48,9 +62,8 @@ irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS)
 	/* VBLANK interrupt */
 	if (status & MGA_VLINEPEN) {
 		MGA_WRITE(MGA_ICLEAR, MGA_VLINEICLR);
-		atomic_inc(&dev->vbl_received);
-		DRM_WAKEUP(&dev->vbl_queue);
-		drm_vbl_send_signals(dev);
+		atomic_inc(&dev_priv->vbl_received);
+		drm_handle_vblank(dev, 0);
 		handled = 1;
 	}
 
@@ -74,30 +87,41 @@ irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS)
 		handled = 1;
 	}
 
-	if ( handled ) {
-		return IRQ_HANDLED;
-	}
-	return IRQ_NONE;
+	return (handled) ? IRQ_HANDLED : IRQ_NONE;
 }
 
-int mga_driver_vblank_wait(drm_device_t * dev, unsigned int *sequence)
+
+int mga_enable_vblank(drm_device_t *dev, int crtc)
 {
-	unsigned int cur_vblank;
-	int ret = 0;
+	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 
-	/* Assume that the user has missed the current sequence number
-	 * by about a day rather than she wants to wait for years
-	 * using vertical blanks...
-	 */
-	DRM_WAIT_ON(ret, dev->vbl_queue, 3 * DRM_HZ,
-		    (((cur_vblank = atomic_read(&dev->vbl_received))
-		      - *sequence) <= (1 << 23)));
+	if (crtc != 0) {
+		DRM_ERROR("tried to enable vblank on non-existent crtc %d\n",
+			  crtc);
+		return 0;
+	}
+
+	MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN);
+	return 0;
+}
 
-	*sequence = cur_vblank;
 
-	return ret;
+void mga_disable_vblank(drm_device_t *dev, int crtc)
+{
+	if (crtc != 0) {
+		DRM_ERROR("tried to disable vblank on non-existent crtc %d\n",
+			  crtc);
+	}
+
+	/* Do *NOT* disable the vertical refresh interrupt.  MGA doesn't have
+	 * a nice hardware counter that tracks the number of refreshes when
+	 * the interrupt is disabled, and the kernel doesn't know the refresh
+	 * rate to calculate an estimate.
+	 */
+	/* MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN); */
 }
 
+
 int mga_driver_fence_wait(drm_device_t * dev, unsigned int *sequence)
 {
 	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
@@ -127,16 +151,25 @@ void mga_driver_irq_preinstall(drm_device_t * dev)
 	MGA_WRITE(MGA_ICLEAR, ~0);
 }
 
-void mga_driver_irq_postinstall(drm_device_t * dev)
+int mga_driver_irq_postinstall(drm_device_t * dev)
 {
 	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
+	int ret;
 
-	DRM_INIT_WAITQUEUE( &dev_priv->fence_queue );
+	ret = drm_vblank_init(dev, 1);
+	if (ret)
+		return ret;
 
-	/* Turn on vertical blank interrupt and soft trap interrupt. */
-	MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN);
+	DRM_INIT_WAITQUEUE(&dev_priv->fence_queue);
+
+	/* Turn on soft trap interrupt.  Vertical blank interrupts are enabled
+	 * in mga_enable_vblank.
+	 */
+	MGA_WRITE(MGA_IEN, MGA_SOFTRAPEN);
+	return 0;
 }
 
+
 void mga_driver_irq_uninstall(drm_device_t * dev)
 {
 	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;