drm/vc4: Add support for drawing 3D frames.

The user submission is basically a pointer to a command list and a
pointer to uniforms.  We copy those in to the kernel, validate and
relocate them, and store the result in a GPU BO which we queue for
execution.

v2: Drop support for NV shader recs (not necessary for GL), simplify
    vc4_use_bo(), improve bin flush/semaphore checks, use __u32 style
    types.

Signed-off-by: Eric Anholt <eric@anholt.net>

drivers/gpu/drm/vc4/vc4_irq.c

@@ -0,0 +1,210 @@
+/*
+ * Copyright © 2014 Broadcom
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+/** DOC: Interrupt management for the V3D engine.
+ *
+ * We have an interrupt status register (V3D_INTCTL) which reports
+ * interrupts, and where writing 1 bits clears those interrupts.
+ * There are also a pair of interrupt registers
+ * (V3D_INTENA/V3D_INTDIS) where writing a 1 to their bits enables or
+ * disables that specific interrupt, and 0s written are ignored
+ * (reading either one returns the set of enabled interrupts).
+ *
+ * When we take a render frame interrupt, we need to wake the
+ * processes waiting for some frame to be done, and get the next frame
+ * submitted ASAP (so the hardware doesn't sit idle when there's work
+ * to do).
+ *
+ * When we take the binner out of memory interrupt, we need to
+ * allocate some new memory and pass it to the binner so that the
+ * current job can make progress.
+ */
+
+#include "vc4_drv.h"
+#include "vc4_regs.h"
+
+#define V3D_DRIVER_IRQS (V3D_INT_OUTOMEM | \
+			 V3D_INT_FRDONE)
+
+DECLARE_WAIT_QUEUE_HEAD(render_wait);
+
+static void
+vc4_overflow_mem_work(struct work_struct *work)
+{
+	struct vc4_dev *vc4 =
+		container_of(work, struct vc4_dev, overflow_mem_work);
+	struct drm_device *dev = vc4->dev;
+	struct vc4_bo *bo;
+
+	bo = vc4_bo_create(dev, 256 * 1024, true);
+	if (!bo) {
+		DRM_ERROR("Couldn't allocate binner overflow mem\n");
+		return;
+	}
+
+	/* If there's a job executing currently, then our previous
+	 * overflow allocation is getting used in that job and we need
+	 * to queue it to be released when the job is done.  But if no
+	 * job is executing at all, then we can free the old overflow
+	 * object direcctly.
+	 *
+	 * No lock necessary for this pointer since we're the only
+	 * ones that update the pointer, and our workqueue won't
+	 * reenter.
+	 */
+	if (vc4->overflow_mem) {
+		struct vc4_exec_info *current_exec;
+		unsigned long irqflags;
+
+		spin_lock_irqsave(&vc4->job_lock, irqflags);
+		current_exec = vc4_first_job(vc4);
+		if (current_exec) {
+			vc4->overflow_mem->seqno = vc4->finished_seqno + 1;
+			list_add_tail(&vc4->overflow_mem->unref_head,
+				      &current_exec->unref_list);
+			vc4->overflow_mem = NULL;
+		}
+		spin_unlock_irqrestore(&vc4->job_lock, irqflags);
+	}
+
+	if (vc4->overflow_mem)
+		drm_gem_object_unreference_unlocked(&vc4->overflow_mem->base.base);
+	vc4->overflow_mem = bo;
+
+	V3D_WRITE(V3D_BPOA, bo->base.paddr);
+	V3D_WRITE(V3D_BPOS, bo->base.base.size);
+	V3D_WRITE(V3D_INTCTL, V3D_INT_OUTOMEM);
+	V3D_WRITE(V3D_INTENA, V3D_INT_OUTOMEM);
+}
+
+static void
+vc4_irq_finish_job(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct vc4_exec_info *exec = vc4_first_job(vc4);
+
+	if (!exec)
+		return;
+
+	vc4->finished_seqno++;
+	list_move_tail(&exec->head, &vc4->job_done_list);
+	vc4_submit_next_job(dev);
+
+	wake_up_all(&vc4->job_wait_queue);
+	schedule_work(&vc4->job_done_work);
+}
+
+irqreturn_t
+vc4_irq(int irq, void *arg)
+{
+	struct drm_device *dev = arg;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	uint32_t intctl;
+	irqreturn_t status = IRQ_NONE;
+
+	barrier();
+	intctl = V3D_READ(V3D_INTCTL);
+
+	/* Acknowledge the interrupts we're handling here. The render
+	 * frame done interrupt will be cleared, while OUTOMEM will
+	 * stay high until the underlying cause is cleared.
+	 */
+	V3D_WRITE(V3D_INTCTL, intctl);
+
+	if (intctl & V3D_INT_OUTOMEM) {
+		/* Disable OUTOMEM until the work is done. */
+		V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
+		schedule_work(&vc4->overflow_mem_work);
+		status = IRQ_HANDLED;
+	}
+
+	if (intctl & V3D_INT_FRDONE) {
+		spin_lock(&vc4->job_lock);
+		vc4_irq_finish_job(dev);
+		spin_unlock(&vc4->job_lock);
+		status = IRQ_HANDLED;
+	}
+
+	return status;
+}
+
+void
+vc4_irq_preinstall(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	init_waitqueue_head(&vc4->job_wait_queue);
+	INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
+
+	/* Clear any pending interrupts someone might have left around
+	 * for us.
+	 */
+	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
+}
+
+int
+vc4_irq_postinstall(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	/* Enable both the render done and out of memory interrupts. */
+	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
+
+	return 0;
+}
+
+void
+vc4_irq_uninstall(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	/* Disable sending interrupts for our driver's IRQs. */
+	V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
+
+	/* Clear any pending interrupts we might have left. */
+	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
+
+	cancel_work_sync(&vc4->overflow_mem_work);
+}
+
+/** Reinitializes interrupt registers when a GPU reset is performed. */
+void vc4_irq_reset(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	unsigned long irqflags;
+
+	/* Acknowledge any stale IRQs. */
+	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
+
+	/*
+	 * Turn all our interrupts on.  Binner out of memory is the
+	 * only one we expect to trigger at this point, since we've
+	 * just come from poweron and haven't supplied any overflow
+	 * memory yet.
+	 */
+	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
+
+	spin_lock_irqsave(&vc4->job_lock, irqflags);
+	vc4_irq_finish_job(dev);
+	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
+}