Add i915 ioctls to configure pipes for vblank interrupt.

i915 vblanks can be generated from either pipe a or b, however a disabled
pipe generates no interrupts. This change allows the X server to select
which pipe generates vblank interrupts.

From: Keith Packard <[e-mail]> via DRM CVS
Signed-off-by: Dave Airlie <[e-mail]>

drivers/char/drm/i915_dma.c

···
 	[DRM_IOCTL_NR(DRM_I915_FREE)] = {i915_mem_free, DRM_AUTH},
 	[DRM_IOCTL_NR(DRM_I915_INIT_HEAP)] = {i915_mem_init_heap, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 	[DRM_IOCTL_NR(DRM_I915_CMDBUFFER)] = {i915_cmdbuffer, DRM_AUTH},
-	[DRM_IOCTL_NR(DRM_I915_DESTROY_HEAP)] = { i915_mem_destroy_heap, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY }
+	[DRM_IOCTL_NR(DRM_I915_DESTROY_HEAP)] = { i915_mem_destroy_heap, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY },
+	[DRM_IOCTL_NR(DRM_I915_SET_VBLANK_PIPE)] = { i915_vblank_pipe_set, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY },
+	[DRM_IOCTL_NR(DRM_I915_GET_VBLANK_PIPE)] = { i915_vblank_pipe_get, DRM_AUTH },
 };
 
 int i915_max_ioctl = DRM_ARRAY_SIZE(i915_ioctls);

drivers/char/drm/i915_drm.h

···
 #define DRM_I915_INIT_HEAP	0x0a
 #define DRM_I915_CMDBUFFER	0x0b
 #define DRM_I915_DESTROY_HEAP	0x0c
+#define DRM_I915_SET_VBLANK_PIPE	0x0d
+#define DRM_I915_GET_VBLANK_PIPE	0x0e
 
 #define DRM_IOCTL_I915_INIT		DRM_IOW( DRM_COMMAND_BASE + DRM_I915_INIT, drm_i915_init_t)
 #define DRM_IOCTL_I915_FLUSH		DRM_IO ( DRM_COMMAND_BASE + DRM_I915_FLUSH)
···
 #define DRM_IOCTL_I915_INIT_HEAP        DRM_IOW( DRM_COMMAND_BASE + DRM_I915_INIT_HEAP, drm_i915_mem_init_heap_t)
 #define DRM_IOCTL_I915_CMDBUFFER	DRM_IOW( DRM_COMMAND_BASE + DRM_I915_CMDBUFFER, drm_i915_cmdbuffer_t)
 #define DRM_IOCTL_I915_DESTROY_HEAP	DRM_IOW( DRM_COMMAND_BASE + DRM_I915_DESTROY_HEAP, drm_i915_mem_destroy_heap_t)
+#define DRM_IOCTL_I915_SET_VBLANK_PIPE	DRM_IOW( DRM_COMMAND_BASE + DRM_I915_SET_VBLANK_PIPE, drm_i915_vblank_pipe_t)
+#define DRM_IOCTL_I915_GET_VBLANK_PIPE	DRM_IOR( DRM_COMMAND_BASE + DRM_I915_GET_VBLANK_PIPE, drm_i915_vblank_pipe_t)
 
 /* Allow drivers to submit batchbuffers directly to hardware, relying
  * on the security mechanisms provided by hardware.
···
 typedef struct drm_i915_mem_destroy_heap {
 	int region;
 } drm_i915_mem_destroy_heap_t;
+
+/* Allow X server to configure which pipes to monitor for vblank signals
+ */
+#define	DRM_I915_VBLANK_PIPE_A	1
+#define	DRM_I915_VBLANK_PIPE_B	2
+
+typedef struct drm_i915_vblank_pipe {
+	int pipe;
+} drm_i915_vblank_pipe_t;
 
 #endif				/* _I915_DRM_H_ */

drivers/char/drm/i915_drv.h

···
  * 1.2: Add Power Management
  * 1.3: Add vblank support
  * 1.4: Fix cmdbuffer path, add heap destroy
+ * 1.5: Add vblank pipe configuration
  */
 #define DRIVER_MAJOR		1
-#define DRIVER_MINOR		4
+#define DRIVER_MINOR		5
 #define DRIVER_PATCHLEVEL	0
 
 typedef struct _drm_i915_ring_buffer {
···
 	int allow_batchbuffer;
 	struct mem_block *agp_heap;
 	unsigned int sr01, adpa, ppcr, dvob, dvoc, lvds;
+	int vblank_pipe;
 } drm_i915_private_t;
 
 extern drm_ioctl_desc_t i915_ioctls[];
···
 extern void i915_driver_irq_preinstall(drm_device_t * dev);
 extern void i915_driver_irq_postinstall(drm_device_t * dev);
 extern void i915_driver_irq_uninstall(drm_device_t * dev);
+extern int i915_vblank_pipe_set(DRM_IOCTL_ARGS);
+extern int i915_vblank_pipe_get(DRM_IOCTL_ARGS);
 
 /* i915_mem.c */
 extern int i915_mem_alloc(DRM_IOCTL_ARGS);

drivers/char/drm/i915_irq.c

···
 	u16 temp;
 
 	temp = I915_READ16(I915REG_INT_IDENTITY_R);
-	temp &= (USER_INT_FLAG | VSYNC_PIPEA_FLAG);
+
+	temp &= (USER_INT_FLAG | VSYNC_PIPEA_FLAG | VSYNC_PIPEB_FLAG);
 
 	DRM_DEBUG("%s flag=%08x\n", __FUNCTION__, temp);
 
···
 	if (temp & USER_INT_FLAG)
 		DRM_WAKEUP(&dev_priv->irq_queue);
 
-	if (temp & VSYNC_PIPEA_FLAG) {
+	if (temp & (VSYNC_PIPEA_FLAG | VSYNC_PIPEB_FLAG)) {
 		atomic_inc(&dev->vbl_received);
 		DRM_WAKEUP(&dev->vbl_queue);
 		drm_vbl_send_signals(dev);
···
 	return i915_wait_irq(dev, irqwait.irq_seq);
 }
 
+static int i915_enable_interrupt (drm_device_t *dev)
+{
+	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
+	u16 flag;
+
+	flag = 0;
+	if (dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_A)
+		flag |= VSYNC_PIPEA_FLAG;
+	if (dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B)
+		flag |= VSYNC_PIPEB_FLAG;
+	if (dev_priv->vblank_pipe & ~(DRM_I915_VBLANK_PIPE_A|DRM_I915_VBLANK_PIPE_B)) {
+		DRM_ERROR("%s called with invalid pipe 0x%x\n",
+			  __FUNCTION__, dev_priv->vblank_pipe);
+		return DRM_ERR(EINVAL);
+	}
+	I915_WRITE16(I915REG_INT_ENABLE_R, USER_INT_FLAG | flag);
+	return 0;
+}
+
+/* Set the vblank monitor pipe
+ */
+int i915_vblank_pipe_set(DRM_IOCTL_ARGS)
+{
+	DRM_DEVICE;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	drm_i915_vblank_pipe_t pipe;
+
+	if (!dev_priv) {
+		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
+		return DRM_ERR(EINVAL);
+	}
+
+	DRM_COPY_FROM_USER_IOCTL(pipe, (drm_i915_vblank_pipe_t __user *) data,
+				 sizeof(pipe));
+
+	dev_priv->vblank_pipe = pipe.pipe;
+	return i915_enable_interrupt (dev);
+}
+
+int i915_vblank_pipe_get(DRM_IOCTL_ARGS)
+{
+	DRM_DEVICE;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	drm_i915_vblank_pipe_t pipe;
+	u16 flag;
+
+	if (!dev_priv) {
+		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
+		return DRM_ERR(EINVAL);
+	}
+
+	flag = I915_READ(I915REG_INT_ENABLE_R);
+	pipe.pipe = 0;
+	if (flag & VSYNC_PIPEA_FLAG)
+		pipe.pipe |= DRM_I915_VBLANK_PIPE_A;
+	if (flag & VSYNC_PIPEB_FLAG)
+		pipe.pipe |= DRM_I915_VBLANK_PIPE_B;
+	DRM_COPY_TO_USER_IOCTL((drm_i915_vblank_pipe_t __user *) data, pipe,
+				 sizeof(pipe));
+	return 0;
+}
+
 /* drm_dma.h hooks
 */
 void i915_driver_irq_preinstall(drm_device_t * dev)
···
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 
-	I915_WRITE16(I915REG_INT_ENABLE_R, USER_INT_FLAG | VSYNC_PIPEA_FLAG);
+	i915_enable_interrupt(dev);
 	DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
 }