drm/vbl rework: rework how the drm deals with vblank.

Other Authors: Michel Dänzer <michel@tungstengraphics.com>
mga: Ian Romanick <idr@us.ibm.com>
via: Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>

This re-works the DRM internals to provide a better interface for drivers
to expose vblank on multiple crtcs.

It also includes work done by Michel on making i915 triple buffering and pageflipping work properly.

Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/char/drm/drm.h

@@ -471,6 +471,7 @@ struct drm_irq_busid {
 enum drm_vblank_seq_type {
 	_DRM_VBLANK_ABSOLUTE = 0x0,	/**< Wait for specific vblank sequence number */
 	_DRM_VBLANK_RELATIVE = 0x1,	/**< Wait for given number of vblanks */
+	_DRM_VBLANK_FLIP = 0x8000000,	/**< Scheduled buffer swap should flip */
 	_DRM_VBLANK_NEXTONMISS = 0x10000000,	/**< If missed, wait for next vblank */
 	_DRM_VBLANK_SECONDARY = 0x20000000,	/**< Secondary display controller */
 	_DRM_VBLANK_SIGNAL = 0x40000000	/**< Send signal instead of blocking */
@@ -503,6 +504,21 @@ union drm_wait_vblank {
 	struct drm_wait_vblank_reply reply;
 };
 
+enum drm_modeset_ctl_cmd {
+	_DRM_PRE_MODESET = 1,
+	_DRM_POST_MODESET = 2,
+};
+
+/**
+ * DRM_IOCTL_MODESET_CTL ioctl argument type
+ *
+ * \sa drmModesetCtl().
+ */
+struct drm_modeset_ctl {
+	unsigned long arg;
+	enum drm_modeset_ctl_cmd cmd;
+};
+
 /**
  * DRM_IOCTL_AGP_ENABLE ioctl argument type.
  *
@@ -587,6 +603,7 @@ struct drm_set_version {
 #define DRM_IOCTL_GET_CLIENT            DRM_IOWR(0x05, struct drm_client)
 #define DRM_IOCTL_GET_STATS             DRM_IOR( 0x06, struct drm_stats)
 #define DRM_IOCTL_SET_VERSION		DRM_IOWR(0x07, struct drm_set_version)
+#define DRM_IOCTL_MODESET_CTL           DRM_IOW(0x08, struct drm_modeset_ctl)
 
 #define DRM_IOCTL_SET_UNIQUE		DRM_IOW( 0x10, struct drm_unique)
 #define DRM_IOCTL_AUTH_MAGIC		DRM_IOW( 0x11, struct drm_auth)

drivers/char/drm/drmP.h

@@ -100,10 +100,8 @@ struct drm_device;
 #define DRIVER_HAVE_DMA    0x20
 #define DRIVER_HAVE_IRQ    0x40
 #define DRIVER_IRQ_SHARED  0x80
-#define DRIVER_IRQ_VBL     0x100
 #define DRIVER_DMA_QUEUE   0x200
 #define DRIVER_FB_DMA      0x400
-#define DRIVER_IRQ_VBL2    0x800
 
 /***********************************************************************/
 /** \name Begin the DRM... */
@@ -579,10 +577,52 @@ struct drm_driver {
 	int (*context_dtor) (struct drm_device *dev, int context);
 	int (*kernel_context_switch) (struct drm_device *dev, int old,
 				      int new);
-	void (*kernel_context_switch_unlock) (struct drm_device *dev);
-	int (*vblank_wait) (struct drm_device *dev, unsigned int *sequence);
-	int (*vblank_wait2) (struct drm_device *dev, unsigned int *sequence);
-	int (*dri_library_name) (struct drm_device *dev, char *buf);
+	void (*kernel_context_switch_unlock) (struct drm_device * dev);
+	/**
+	 * get_vblank_counter - get raw hardware vblank counter
+	 * @dev: DRM device
+	 * @crtc: counter to fetch
+	 *
+	 * Driver callback for fetching a raw hardware vblank counter
+	 * for @crtc.  If a device doesn't have a hardware counter, the
+	 * driver can simply return the value of drm_vblank_count and
+	 * make the enable_vblank() and disable_vblank() hooks into no-ops,
+	 * leaving interrupts enabled at all times.
+	 *
+	 * Wraparound handling and loss of events due to modesetting is dealt
+	 * with in the DRM core code.
+	 *
+	 * RETURNS
+	 * Raw vblank counter value.
+	 */
+	u32 (*get_vblank_counter) (struct drm_device *dev, int crtc);
+
+	/**
+	 * enable_vblank - enable vblank interrupt events
+	 * @dev: DRM device
+	 * @crtc: which irq to enable
+	 *
+	 * Enable vblank interrupts for @crtc.  If the device doesn't have
+	 * a hardware vblank counter, this routine should be a no-op, since
+	 * interrupts will have to stay on to keep the count accurate.
+	 *
+	 * RETURNS
+	 * Zero on success, appropriate errno if the given @crtc's vblank
+	 * interrupt cannot be enabled.
+	 */
+	int (*enable_vblank) (struct drm_device *dev, int crtc);
+
+	/**
+	 * disable_vblank - disable vblank interrupt events
+	 * @dev: DRM device
+	 * @crtc: which irq to enable
+	 *
+	 * Disable vblank interrupts for @crtc.  If the device doesn't have
+	 * a hardware vblank counter, this routine should be a no-op, since
+	 * interrupts will have to stay on to keep the count accurate.
+	 */
+	void (*disable_vblank) (struct drm_device *dev, int crtc);
+	int (*dri_library_name) (struct drm_device *dev, char * buf);
 
 	/**
 	 * Called by \c drm_device_is_agp.  Typically used to determine if a
@@ -601,7 +641,7 @@ struct drm_driver {
 
 	irqreturn_t(*irq_handler) (DRM_IRQ_ARGS);
 	void (*irq_preinstall) (struct drm_device *dev);
-	void (*irq_postinstall) (struct drm_device *dev);
+	int (*irq_postinstall) (struct drm_device *dev);
 	void (*irq_uninstall) (struct drm_device *dev);
 	void (*reclaim_buffers) (struct drm_device *dev,
 				 struct drm_file * file_priv);
@@ -730,13 +770,21 @@ struct drm_device {
 	/** \name VBLANK IRQ support */
 	/*@{ */
 
-	wait_queue_head_t vbl_queue;	/**< VBLANK wait queue */
-	atomic_t vbl_received;
-	atomic_t vbl_received2;		/**< number of secondary VBLANK interrupts */
+	wait_queue_head_t *vbl_queue;	/**< VBLANK wait queue */
+	atomic_t *_vblank_count;	/**< number of VBLANK interrupts (driver must alloc the right number of counters) */
 	spinlock_t vbl_lock;
-	struct list_head vbl_sigs;		/**< signal list to send on VBLANK */
-	struct list_head vbl_sigs2;	/**< signals to send on secondary VBLANK */
-	unsigned int vbl_pending;
+	struct list_head *vbl_sigs;		/**< signal list to send on VBLANK */
+	atomic_t vbl_signal_pending;	/* number of signals pending on all crtcs*/
+	atomic_t *vblank_refcount;	/* number of users of vblank interrupts per crtc */
+	u32 *last_vblank;		/* protected by dev->vbl_lock, used */
+					/* for wraparound handling */
+	u32 *vblank_offset;		/* used to track how many vblanks */
+	int *vblank_enabled;		/* so we don't call enable more than
+					   once per disable */
+	u32 *vblank_premodeset;		/*  were lost during modeset */
+	struct timer_list vblank_disable_timer;
+
+	unsigned long max_vblank_count; /**< size of vblank counter register */
 	spinlock_t tasklet_lock;	/**< For drm_locked_tasklet */
 	void (*locked_tasklet_func)(struct drm_device *dev);
 
@@ -756,6 +804,7 @@ struct drm_device {
 #ifdef __alpha__
 	struct pci_controller *hose;
 #endif
+	int num_crtcs;			/**< Number of CRTCs on this device */
 	struct drm_sg_mem *sg;	/**< Scatter gather memory */
 	void *dev_private;		/**< device private data */
 	struct drm_sigdata sigdata;	   /**< For block_all_signals */
@@ -990,11 +1039,19 @@ extern void drm_driver_irq_preinstall(struct drm_device *dev);
 extern void drm_driver_irq_postinstall(struct drm_device *dev);
 extern void drm_driver_irq_uninstall(struct drm_device *dev);
 
-extern int drm_wait_vblank(struct drm_device *dev, void *data,
-			   struct drm_file *file_priv);
-extern int drm_vblank_wait(struct drm_device *dev, unsigned int *vbl_seq);
-extern void drm_vbl_send_signals(struct drm_device *dev);
+extern int drm_vblank_init(struct drm_device *dev, int num_crtcs);
+extern int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *filp);
+extern int drm_vblank_wait(struct drm_device * dev, unsigned int *vbl_seq);
 extern void drm_locked_tasklet(struct drm_device *dev, void(*func)(struct drm_device*));
+extern u32 drm_vblank_count(struct drm_device *dev, int crtc);
+extern void drm_update_vblank_count(struct drm_device *dev, int crtc);
+extern void drm_handle_vblank(struct drm_device *dev, int crtc);
+extern int drm_vblank_get(struct drm_device *dev, int crtc);
+extern void drm_vblank_put(struct drm_device *dev, int crtc);
+
+				/* Modesetting support */
+extern int drm_modeset_ctl(struct drm_device *dev, void *data,
+			   struct drm_file *file_priv);
 
 				/* AGP/GART support (drm_agpsupport.h) */
 extern struct drm_agp_head *drm_agp_init(struct drm_device *dev);