1/*
  2 * Copyright (C) 2013-2016 Red Hat
  3 * Author: Rob Clark <robdclark@gmail.com>
  4 *
  5 * This program is free software; you can redistribute it and/or modify it
  6 * under the terms of the GNU General Public License version 2 as published by
  7 * the Free Software Foundation.
  8 *
  9 * This program is distributed in the hope that it will be useful, but WITHOUT
 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 12 * more details.
 13 *
 14 * You should have received a copy of the GNU General Public License along with
 15 * this program.  If not, see <http://www.gnu.org/licenses/>.
 16 */
 17
 18#include <linux/dma-fence.h>
 19
 20#include "msm_drv.h"
 21#include "msm_fence.h"
 22
 23
 24struct msm_fence_context *
 25msm_fence_context_alloc(struct drm_device *dev, const char *name)
 26{
 27	struct msm_fence_context *fctx;
 28
 29	fctx = kzalloc(sizeof(*fctx), GFP_KERNEL);
 30	if (!fctx)
 31		return ERR_PTR(-ENOMEM);
 32
 33	fctx->dev = dev;
 34	strncpy(fctx->name, name, sizeof(fctx->name));
 35	fctx->context = dma_fence_context_alloc(1);
 36	init_waitqueue_head(&fctx->event);
 37	spin_lock_init(&fctx->spinlock);
 38
 39	return fctx;
 40}
 41
 42void msm_fence_context_free(struct msm_fence_context *fctx)
 43{
 44	kfree(fctx);
 45}
 46
 47static inline bool fence_completed(struct msm_fence_context *fctx, uint32_t fence)
 48{
 49	return (int32_t)(fctx->completed_fence - fence) >= 0;
 50}
 51
 52/* legacy path for WAIT_FENCE ioctl: */
 53int msm_wait_fence(struct msm_fence_context *fctx, uint32_t fence,
 54		ktime_t *timeout, bool interruptible)
 55{
 56	int ret;
 57
 58	if (fence > fctx->last_fence) {
 59		DRM_ERROR("%s: waiting on invalid fence: %u (of %u)\n",
 60				fctx->name, fence, fctx->last_fence);
 61		return -EINVAL;
 62	}
 63
 64	if (!timeout) {
 65		/* no-wait: */
 66		ret = fence_completed(fctx, fence) ? 0 : -EBUSY;
 67	} else {
 68		unsigned long remaining_jiffies = timeout_to_jiffies(timeout);
 69
 70		if (interruptible)
 71			ret = wait_event_interruptible_timeout(fctx->event,
 72				fence_completed(fctx, fence),
 73				remaining_jiffies);
 74		else
 75			ret = wait_event_timeout(fctx->event,
 76				fence_completed(fctx, fence),
 77				remaining_jiffies);
 78
 79		if (ret == 0) {
 80			DBG("timeout waiting for fence: %u (completed: %u)",
 81					fence, fctx->completed_fence);
 82			ret = -ETIMEDOUT;
 83		} else if (ret != -ERESTARTSYS) {
 84			ret = 0;
 85		}
 86	}
 87
 88	return ret;
 89}
 90
 91/* called from workqueue */
 92void msm_update_fence(struct msm_fence_context *fctx, uint32_t fence)
 93{
 94	spin_lock(&fctx->spinlock);
 95	fctx->completed_fence = max(fence, fctx->completed_fence);
 96	spin_unlock(&fctx->spinlock);
 97
 98	wake_up_all(&fctx->event);
 99}
100
101struct msm_fence {
102	struct dma_fence base;
103	struct msm_fence_context *fctx;
104};
105
106static inline struct msm_fence *to_msm_fence(struct dma_fence *fence)
107{
108	return container_of(fence, struct msm_fence, base);
109}
110
111static const char *msm_fence_get_driver_name(struct dma_fence *fence)
112{
113	return "msm";
114}
115
116static const char *msm_fence_get_timeline_name(struct dma_fence *fence)
117{
118	struct msm_fence *f = to_msm_fence(fence);
119	return f->fctx->name;
120}
121
122static bool msm_fence_enable_signaling(struct dma_fence *fence)
123{
124	return true;
125}
126
127static bool msm_fence_signaled(struct dma_fence *fence)
128{
129	struct msm_fence *f = to_msm_fence(fence);
130	return fence_completed(f->fctx, f->base.seqno);
131}
132
133static const struct dma_fence_ops msm_fence_ops = {
134	.get_driver_name = msm_fence_get_driver_name,
135	.get_timeline_name = msm_fence_get_timeline_name,
136	.enable_signaling = msm_fence_enable_signaling,
137	.signaled = msm_fence_signaled,
138	.wait = dma_fence_default_wait,
139	.release = dma_fence_free,
140};
141
142struct dma_fence *
143msm_fence_alloc(struct msm_fence_context *fctx)
144{
145	struct msm_fence *f;
146
147	f = kzalloc(sizeof(*f), GFP_KERNEL);
148	if (!f)
149		return ERR_PTR(-ENOMEM);
150
151	f->fctx = fctx;
152
153	dma_fence_init(&f->base, &msm_fence_ops, &fctx->spinlock,
154		       fctx->context, ++fctx->last_fence);
155
156	return &f->base;
157}