drm/vmwgfx: Add DRM driver for VMware Virtual GPU

This commit adds the vmwgfx driver for the VWware Virtual GPU aka SVGA.
The driver is under staging the same as Nouveau and Radeon KMS. Hopefully
the 2D ioctls are bug free and don't need changing, so that part of the
API should be stable. But there there is a pretty big chance that the 3D API
will change in the future.

Signed-off-by: Thomas Hellström <thellstrom@vmware.com>
Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 295 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_irq.c b/drivers/gpu/drm/vmwgfx/vmwgfx_irq.c
new file mode 100644
index 000000000000..9e0f0306eedb
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_irq.c
@@ -0,0 +1,295 @@
+/**************************************************************************
+ *
+ * Copyright © 2009 VMware, Inc., Palo Alto, CA., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#include "drmP.h"
+#include "vmwgfx_drv.h"
+
+#define VMW_FENCE_WRAP (1 << 24)
+
+irqreturn_t vmw_irq_handler(DRM_IRQ_ARGS)
+{
+	struct drm_device *dev = (struct drm_device *)arg;
+	struct vmw_private *dev_priv = vmw_priv(dev);
+	uint32_t status;
+
+	spin_lock(&dev_priv->irq_lock);
+	status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+	spin_unlock(&dev_priv->irq_lock);
+
+	if (status & SVGA_IRQFLAG_ANY_FENCE)
+		wake_up_all(&dev_priv->fence_queue);
+	if (status & SVGA_IRQFLAG_FIFO_PROGRESS)
+		wake_up_all(&dev_priv->fifo_queue);
+
+	if (likely(status)) {
+		outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static bool vmw_fifo_idle(struct vmw_private *dev_priv, uint32_t sequence)
+{
+	uint32_t busy;
+
+	mutex_lock(&dev_priv->hw_mutex);
+	busy = vmw_read(dev_priv, SVGA_REG_BUSY);
+	mutex_unlock(&dev_priv->hw_mutex);
+
+	return (busy == 0);
+}
+
+
+bool vmw_fence_signaled(struct vmw_private *dev_priv,
+			uint32_t sequence)
+{
+	__le32 __iomem *fifo_mem = dev_priv->mmio_virt;
+	struct vmw_fifo_state *fifo_state;
+	bool ret;
+
+	if (likely(dev_priv->last_read_sequence - sequence < VMW_FENCE_WRAP))
+		return true;
+
+	dev_priv->last_read_sequence = ioread32(fifo_mem + SVGA_FIFO_FENCE);
+	if (likely(dev_priv->last_read_sequence - sequence < VMW_FENCE_WRAP))
+		return true;
+
+	fifo_state = &dev_priv->fifo;
+	if (!(fifo_state->capabilities & SVGA_FIFO_CAP_FENCE) &&
+	    vmw_fifo_idle(dev_priv, sequence))
+		return true;
+
+	/**
+	 * Below is to signal stale fences that have wrapped.
+	 * First, block fence submission.
+	 */
+
+	down_read(&fifo_state->rwsem);
+
+	/**
+	 * Then check if the sequence is higher than what we've actually
+	 * emitted. Then the fence is stale and signaled.
+	 */
+
+	ret = ((dev_priv->fence_seq - sequence) > VMW_FENCE_WRAP);
+	up_read(&fifo_state->rwsem);
+
+	return ret;
+}
+
+int vmw_fallback_wait(struct vmw_private *dev_priv,
+		      bool lazy,
+		      bool fifo_idle,
+		      uint32_t sequence,
+		      bool interruptible,
+		      unsigned long timeout)
+{
+	struct vmw_fifo_state *fifo_state = &dev_priv->fifo;
+
+	uint32_t count = 0;
+	uint32_t signal_seq;
+	int ret;
+	unsigned long end_jiffies = jiffies + timeout;
+	bool (*wait_condition)(struct vmw_private *, uint32_t);
+	DEFINE_WAIT(__wait);
+
+	wait_condition = (fifo_idle) ? &vmw_fifo_idle :
+		&vmw_fence_signaled;
+
+	/**
+	 * Block command submission while waiting for idle.
+	 */
+
+	if (fifo_idle)
+		down_read(&fifo_state->rwsem);
+	signal_seq = dev_priv->fence_seq;
+	ret = 0;
+
+	for (;;) {
+		prepare_to_wait(&dev_priv->fence_queue, &__wait,
+				(interruptible) ?
+				TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+		if (wait_condition(dev_priv, sequence))
+			break;
+		if (time_after_eq(jiffies, end_jiffies)) {
+			DRM_ERROR("SVGA device lockup.\n");
+			break;
+		}
+		if (lazy)
+			schedule_timeout(1);
+		else if ((++count & 0x0F) == 0) {
+			/**
+			 * FIXME: Use schedule_hr_timeout here for
+			 * newer kernels and lower CPU utilization.
+			 */
+
+			__set_current_state(TASK_RUNNING);
+			schedule();
+			__set_current_state((interruptible) ?
+					    TASK_INTERRUPTIBLE :
+					    TASK_UNINTERRUPTIBLE);
+		}
+		if (interruptible && signal_pending(current)) {
+			ret = -ERESTART;
+			break;
+		}
+	}
+	finish_wait(&dev_priv->fence_queue, &__wait);
+	if (ret == 0 && fifo_idle) {
+		__le32 __iomem *fifo_mem = dev_priv->mmio_virt;
+		iowrite32(signal_seq, fifo_mem + SVGA_FIFO_FENCE);
+	}
+	wake_up_all(&dev_priv->fence_queue);
+	if (fifo_idle)
+		up_read(&fifo_state->rwsem);
+
+	return ret;
+}
+
+int vmw_wait_fence(struct vmw_private *dev_priv,
+		   bool lazy, uint32_t sequence,
+		   bool interruptible, unsigned long timeout)
+{
+	long ret;
+	unsigned long irq_flags;
+	struct vmw_fifo_state *fifo = &dev_priv->fifo;
+
+	if (likely(dev_priv->last_read_sequence - sequence < VMW_FENCE_WRAP))
+		return 0;
+
+	if (likely(vmw_fence_signaled(dev_priv, sequence)))
+		return 0;
+
+	vmw_fifo_ping_host(dev_priv, SVGA_SYNC_GENERIC);
+
+	if (!(fifo->capabilities & SVGA_FIFO_CAP_FENCE))
+		return vmw_fallback_wait(dev_priv, lazy, true, sequence,
+					 interruptible, timeout);
+
+	if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
+		return vmw_fallback_wait(dev_priv, lazy, false, sequence,
+					 interruptible, timeout);
+
+	mutex_lock(&dev_priv->hw_mutex);
+	if (atomic_add_return(1, &dev_priv->fence_queue_waiters) > 0) {
+		spin_lock_irqsave(&dev_priv->irq_lock, irq_flags);
+		outl(SVGA_IRQFLAG_ANY_FENCE,
+		     dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+		vmw_write(dev_priv, SVGA_REG_IRQMASK,
+			  vmw_read(dev_priv, SVGA_REG_IRQMASK) |
+			  SVGA_IRQFLAG_ANY_FENCE);
+		spin_unlock_irqrestore(&dev_priv->irq_lock, irq_flags);
+	}
+	mutex_unlock(&dev_priv->hw_mutex);
+
+	if (interruptible)
+		ret = wait_event_interruptible_timeout
+		    (dev_priv->fence_queue,
+		     vmw_fence_signaled(dev_priv, sequence),
+		     timeout);
+	else
+		ret = wait_event_timeout
+		    (dev_priv->fence_queue,
+		     vmw_fence_signaled(dev_priv, sequence),
+		     timeout);
+
+	if (unlikely(ret == -ERESTARTSYS))
+		ret = -ERESTART;
+	else if (unlikely(ret == 0))
+		ret = -EBUSY;
+	else if (likely(ret > 0))
+		ret = 0;
+
+	mutex_lock(&dev_priv->hw_mutex);
+	if (atomic_dec_and_test(&dev_priv->fence_queue_waiters)) {
+		spin_lock_irqsave(&dev_priv->irq_lock, irq_flags);
+		vmw_write(dev_priv, SVGA_REG_IRQMASK,
+			  vmw_read(dev_priv, SVGA_REG_IRQMASK) &
+			  ~SVGA_IRQFLAG_ANY_FENCE);
+		spin_unlock_irqrestore(&dev_priv->irq_lock, irq_flags);
+	}
+	mutex_unlock(&dev_priv->hw_mutex);
+
+	return ret;
+}
+
+void vmw_irq_preinstall(struct drm_device *dev)
+{
+	struct vmw_private *dev_priv = vmw_priv(dev);
+	uint32_t status;
+
+	if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
+		return;
+
+	spin_lock_init(&dev_priv->irq_lock);
+	status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+	outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+}
+
+int vmw_irq_postinstall(struct drm_device *dev)
+{
+	return 0;
+}
+
+void vmw_irq_uninstall(struct drm_device *dev)
+{
+	struct vmw_private *dev_priv = vmw_priv(dev);
+	uint32_t status;
+
+	if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
+		return;
+
+	mutex_lock(&dev_priv->hw_mutex);
+	vmw_write(dev_priv, SVGA_REG_IRQMASK, 0);
+	mutex_unlock(&dev_priv->hw_mutex);
+
+	status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+	outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
+}
+
+#define VMW_FENCE_WAIT_TIMEOUT 3*HZ;
+
+int vmw_fence_wait_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_priv)
+{
+	struct drm_vmw_fence_wait_arg *arg =
+	    (struct drm_vmw_fence_wait_arg *)data;
+	unsigned long timeout;
+
+	if (!arg->cookie_valid) {
+		arg->cookie_valid = 1;
+		arg->kernel_cookie = jiffies + VMW_FENCE_WAIT_TIMEOUT;
+	}
+
+	timeout = jiffies;
+	if (time_after_eq(timeout, (unsigned long)arg->kernel_cookie))
+		return -EBUSY;
+
+	timeout = (unsigned long)arg->kernel_cookie - timeout;
+	return vmw_wait_fence(vmw_priv(dev), true, arg->sequence, true, timeout);
+}