drm/radeon: introduce kernel modesetting for radeon hardware

Add kernel modesetting support to radeon driver, use the ttm memory
manager to manage memory and DRM/GEM to provide userspace API.
In order to avoid backward compatibility issue and to allow clean
design and code the radeon kernel modesetting use different code path
than old radeon/drm driver.

When kernel modesetting is enabled the IOCTL of radeon/drm
driver are considered as invalid and an error message is printed
in the log and they return failure.

KMS enabled userspace will use new API to talk with the radeon/drm
driver. The new API provide functions to create/destroy/share/mmap
buffer object which are then managed by the kernel memory manager
(here TTM). In order to submit command to the GPU the userspace
provide a buffer holding the command stream, along this buffer
userspace have to provide a list of buffer object used by the
command stream. The kernel radeon driver will then place buffer
in GPU accessible memory and will update command stream to reflect
the position of the different buffers.

The kernel will also perform security check on command stream
provided by the user, we want to catch and forbid any illegal use
of the GPU such as DMA into random system memory or into memory
not owned by the process supplying the command stream. This part
of the code is still incomplete and this why we propose that patch
as a staging driver addition, future security might forbid current
experimental userspace to run.

This code support the following hardware : R1XX,R2XX,R3XX,R4XX,R5XX
(radeon up to X1950). Works is underway to provide support for R6XX,
R7XX and newer hardware (radeon from HD2XXX to HD4XXX).

Authors:
    Jerome Glisse <jglisse@redhat.com>
    Dave Airlie <airlied@redhat.com>
    Alex Deucher <alexdeucher@gmail.com>

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 387 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
new file mode 100644
index 000000000000..96afbf5ae2ad
--- /dev/null
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -0,0 +1,387 @@
+/*
+ * Copyright 2009 Jerome Glisse.
+ * 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 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.
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ */
+/*
+ * Authors:
+ *    Jerome Glisse <glisse@freedesktop.org>
+ *    Dave Airlie
+ */
+#include <linux/seq_file.h>
+#include <asm/atomic.h>
+#include <linux/wait.h>
+#include <linux/list.h>
+#include <linux/kref.h>
+#include "drmP.h"
+#include "drm.h"
+#include "radeon_reg.h"
+#include "radeon.h"
+
+int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence)
+{
+	unsigned long irq_flags;
+
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	if (fence->emited) {
+		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+		return 0;
+	}
+	fence->seq = atomic_add_return(1, &rdev->fence_drv.seq);
+	if (!rdev->cp.ready) {
+		/* FIXME: cp is not running assume everythings is done right
+		 * away
+		 */
+		WREG32(rdev->fence_drv.scratch_reg, fence->seq);
+	} else {
+		radeon_fence_ring_emit(rdev, fence);
+	}
+	fence->emited = true;
+	fence->timeout = jiffies + ((2000 * HZ) / 1000);
+	list_del(&fence->list);
+	list_add_tail(&fence->list, &rdev->fence_drv.emited);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	return 0;
+}
+
+static bool radeon_fence_poll_locked(struct radeon_device *rdev)
+{
+	struct radeon_fence *fence;
+	struct list_head *i, *n;
+	uint32_t seq;
+	bool wake = false;
+
+	if (rdev == NULL) {
+		return true;
+	}
+	if (rdev->shutdown) {
+		return true;
+	}
+	seq = RREG32(rdev->fence_drv.scratch_reg);
+	rdev->fence_drv.last_seq = seq;
+	n = NULL;
+	list_for_each(i, &rdev->fence_drv.emited) {
+		fence = list_entry(i, struct radeon_fence, list);
+		if (fence->seq == seq) {
+			n = i;
+			break;
+		}
+	}
+	/* all fence previous to this one are considered as signaled */
+	if (n) {
+		i = n;
+		do {
+			n = i->prev;
+			list_del(i);
+			list_add_tail(i, &rdev->fence_drv.signaled);
+			fence = list_entry(i, struct radeon_fence, list);
+			fence->signaled = true;
+			i = n;
+		} while (i != &rdev->fence_drv.emited);
+		wake = true;
+	}
+	return wake;
+}
+
+static void radeon_fence_destroy(struct kref *kref)
+{
+	unsigned long irq_flags;
+        struct radeon_fence *fence;
+
+	fence = container_of(kref, struct radeon_fence, kref);
+	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
+	list_del(&fence->list);
+	fence->emited = false;
+	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
+	kfree(fence);
+}
+
+int radeon_fence_create(struct radeon_device *rdev, struct radeon_fence **fence)
+{
+	unsigned long irq_flags;
+
+	*fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL);
+	if ((*fence) == NULL) {
+		return -ENOMEM;
+	}
+	kref_init(&((*fence)->kref));
+	(*fence)->rdev = rdev;
+	(*fence)->emited = false;
+	(*fence)->signaled = false;
+	(*fence)->seq = 0;
+	INIT_LIST_HEAD(&(*fence)->list);
+
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	list_add_tail(&(*fence)->list, &rdev->fence_drv.created);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	return 0;
+}
+
+
+bool radeon_fence_signaled(struct radeon_fence *fence)
+{
+	struct radeon_device *rdev = fence->rdev;
+	unsigned long irq_flags;
+	bool signaled = false;
+
+	if (rdev->gpu_lockup) {
+		return true;
+	}
+	if (fence == NULL) {
+		return true;
+	}
+	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
+	signaled = fence->signaled;
+	/* if we are shuting down report all fence as signaled */
+	if (fence->rdev->shutdown) {
+		signaled = true;
+	}
+	if (!fence->emited) {
+		WARN(1, "Querying an unemited fence : %p !\n", fence);
+		signaled = true;
+	}
+	if (!signaled) {
+		radeon_fence_poll_locked(fence->rdev);
+		signaled = fence->signaled;
+	}
+	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
+	return signaled;
+}
+
+int radeon_fence_wait(struct radeon_fence *fence, bool interruptible)
+{
+	struct radeon_device *rdev;
+	unsigned long cur_jiffies;
+	unsigned long timeout;
+	bool expired = false;
+	int r;
+
+
+	if (fence == NULL) {
+		WARN(1, "Querying an invalid fence : %p !\n", fence);
+		return 0;
+	}
+	rdev = fence->rdev;
+	if (radeon_fence_signaled(fence)) {
+		return 0;
+	}
+retry:
+	cur_jiffies = jiffies;
+	timeout = HZ / 100;
+	if (time_after(fence->timeout, cur_jiffies)) {
+		timeout = fence->timeout - cur_jiffies;
+	}
+	if (interruptible) {
+		r = wait_event_interruptible_timeout(rdev->fence_drv.queue,
+				radeon_fence_signaled(fence), timeout);
+		if (unlikely(r == -ERESTARTSYS)) {
+			return -ERESTART;
+		}
+	} else {
+		r = wait_event_timeout(rdev->fence_drv.queue,
+			 radeon_fence_signaled(fence), timeout);
+	}
+	if (unlikely(!radeon_fence_signaled(fence))) {
+		if (unlikely(r == 0)) {
+			expired = true;
+		}
+		if (unlikely(expired)) {
+			timeout = 1;
+			if (time_after(cur_jiffies, fence->timeout)) {
+				timeout = cur_jiffies - fence->timeout;
+			}
+			timeout = jiffies_to_msecs(timeout);
+			if (timeout > 500) {
+				DRM_ERROR("fence(%p:0x%08X) %lums timeout "
+					  "going to reset GPU\n",
+					  fence, fence->seq, timeout);
+				radeon_gpu_reset(rdev);
+				WREG32(rdev->fence_drv.scratch_reg, fence->seq);
+			}
+		}
+		goto retry;
+	}
+	if (unlikely(expired)) {
+		rdev->fence_drv.count_timeout++;
+		cur_jiffies = jiffies;
+		timeout = 1;
+		if (time_after(cur_jiffies, fence->timeout)) {
+			timeout = cur_jiffies - fence->timeout;
+		}
+		timeout = jiffies_to_msecs(timeout);
+		DRM_ERROR("fence(%p:0x%08X) %lums timeout\n",
+			  fence, fence->seq, timeout);
+		DRM_ERROR("last signaled fence(0x%08X)\n",
+			  rdev->fence_drv.last_seq);
+	}
+	return 0;
+}
+
+int radeon_fence_wait_next(struct radeon_device *rdev)
+{
+	unsigned long irq_flags;
+	struct radeon_fence *fence;
+	int r;
+
+	if (rdev->gpu_lockup) {
+		return 0;
+	}
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	if (list_empty(&rdev->fence_drv.emited)) {
+		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+		return 0;
+	}
+	fence = list_entry(rdev->fence_drv.emited.next,
+			   struct radeon_fence, list);
+	radeon_fence_ref(fence);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	r = radeon_fence_wait(fence, false);
+	radeon_fence_unref(&fence);
+	return r;
+}
+
+int radeon_fence_wait_last(struct radeon_device *rdev)
+{
+	unsigned long irq_flags;
+	struct radeon_fence *fence;
+	int r;
+
+	if (rdev->gpu_lockup) {
+		return 0;
+	}
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	if (list_empty(&rdev->fence_drv.emited)) {
+		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+		return 0;
+	}
+	fence = list_entry(rdev->fence_drv.emited.prev,
+			   struct radeon_fence, list);
+	radeon_fence_ref(fence);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	r = radeon_fence_wait(fence, false);
+	radeon_fence_unref(&fence);
+	return r;
+}
+
+struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
+{
+	kref_get(&fence->kref);
+	return fence;
+}
+
+void radeon_fence_unref(struct radeon_fence **fence)
+{
+	struct radeon_fence *tmp = *fence;
+
+	*fence = NULL;
+	if (tmp) {
+		kref_put(&tmp->kref, &radeon_fence_destroy);
+	}
+}
+
+void radeon_fence_process(struct radeon_device *rdev)
+{
+	unsigned long irq_flags;
+	bool wake;
+
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	wake = radeon_fence_poll_locked(rdev);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	if (wake) {
+		wake_up_all(&rdev->fence_drv.queue);
+	}
+}
+
+int radeon_fence_driver_init(struct radeon_device *rdev)
+{
+	unsigned long irq_flags;
+	int r;
+
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	r = radeon_scratch_get(rdev, &rdev->fence_drv.scratch_reg);
+	if (r) {
+		DRM_ERROR("Fence failed to get a scratch register.");
+		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+		return r;
+	}
+	WREG32(rdev->fence_drv.scratch_reg, 0);
+	atomic_set(&rdev->fence_drv.seq, 0);
+	INIT_LIST_HEAD(&rdev->fence_drv.created);
+	INIT_LIST_HEAD(&rdev->fence_drv.emited);
+	INIT_LIST_HEAD(&rdev->fence_drv.signaled);
+	rdev->fence_drv.count_timeout = 0;
+	init_waitqueue_head(&rdev->fence_drv.queue);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	if (radeon_debugfs_fence_init(rdev)) {
+		DRM_ERROR("Failed to register debugfs file for fence !\n");
+	}
+	return 0;
+}
+
+void radeon_fence_driver_fini(struct radeon_device *rdev)
+{
+	unsigned long irq_flags;
+
+	wake_up_all(&rdev->fence_drv.queue);
+	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
+	radeon_scratch_free(rdev, rdev->fence_drv.scratch_reg);
+	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
+	DRM_INFO("radeon: fence finalized\n");
+}
+
+
+/*
+ * Fence debugfs
+ */
+#if defined(CONFIG_DEBUG_FS)
+static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = (struct drm_info_node *)m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct radeon_device *rdev = dev->dev_private;
+	struct radeon_fence *fence;
+
+	seq_printf(m, "Last signaled fence 0x%08X\n",
+		   RREG32(rdev->fence_drv.scratch_reg));
+	if (!list_empty(&rdev->fence_drv.emited)) {
+		   fence = list_entry(rdev->fence_drv.emited.prev,
+				      struct radeon_fence, list);
+		   seq_printf(m, "Last emited fence %p with 0x%08X\n",
+			      fence,  fence->seq);
+	}
+	return 0;
+}
+
+static struct drm_info_list radeon_debugfs_fence_list[] = {
+	{"radeon_fence_info", &radeon_debugfs_fence_info, 0, NULL},
+};
+#endif
+
+int radeon_debugfs_fence_init(struct radeon_device *rdev)
+{
+#if defined(CONFIG_DEBUG_FS)
+	return radeon_debugfs_add_files(rdev, radeon_debugfs_fence_list, 1);
+#else
+	return 0;
+#endif
+}