1 files changed, 443 insertions, 0 deletions

diff --git a/drivers/media/video/cx18/cx18-queue.c b/drivers/media/video/cx18/cx18-queue.c
new file mode 100644
index 00000000000..8884537bd62
--- /dev/null
+++ b/drivers/media/video/cx18/cx18-queue.c
@@ -0,0 +1,443 @@
+/*
+ *  cx18 buffer queues
+ *
+ *  Derived from ivtv-queue.c
+ *
+ *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
+ *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ *  02111-1307  USA
+ */
+
+#include "cx18-driver.h"
+#include "cx18-queue.h"
+#include "cx18-streams.h"
+#include "cx18-scb.h"
+#include "cx18-io.h"
+
+void cx18_buf_swap(struct cx18_buffer *buf)
+{
+        int i;
+
+        for (i = 0; i < buf->bytesused; i += 4)
+                swab32s((u32 *)(buf->buf + i));
+}
+
+void _cx18_mdl_swap(struct cx18_mdl *mdl)
+{
+        struct cx18_buffer *buf;
+
+        list_for_each_entry(buf, &mdl->buf_list, list) {
+                if (buf->bytesused == 0)
+                        break;
+                cx18_buf_swap(buf);
+        }
+}
+
+void cx18_queue_init(struct cx18_queue *q)
+{
+        INIT_LIST_HEAD(&q->list);
+        atomic_set(&q->depth, 0);
+        q->bytesused = 0;
+}
+
+struct cx18_queue *_cx18_enqueue(struct cx18_stream *s, struct cx18_mdl *mdl,
+                                 struct cx18_queue *q, int to_front)
+{
+        /* clear the mdl if it is not to be enqueued to the full queue */
+        if (q != &s->q_full) {
+                mdl->bytesused = 0;
+                mdl->readpos = 0;
+                mdl->m_flags = 0;
+                mdl->skipped = 0;
+                mdl->curr_buf = NULL;
+        }
+
+        /* q_busy is restricted to a max buffer count imposed by firmware */
+        if (q == &s->q_busy &&
+            atomic_read(&q->depth) >= CX18_MAX_FW_MDLS_PER_STREAM)
+                q = &s->q_free;
+
+        spin_lock(&q->lock);
+
+        if (to_front)
+                list_add(&mdl->list, &q->list); /* LIFO */
+        else
+                list_add_tail(&mdl->list, &q->list); /* FIFO */
+        q->bytesused += mdl->bytesused - mdl->readpos;
+        atomic_inc(&q->depth);
+
+        spin_unlock(&q->lock);
+        return q;
+}
+
+struct cx18_mdl *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
+{
+        struct cx18_mdl *mdl = NULL;
+
+        spin_lock(&q->lock);
+        if (!list_empty(&q->list)) {
+                mdl = list_first_entry(&q->list, struct cx18_mdl, list);
+                list_del_init(&mdl->list);
+                q->bytesused -= mdl->bytesused - mdl->readpos;
+                mdl->skipped = 0;
+                atomic_dec(&q->depth);
+        }
+        spin_unlock(&q->lock);
+        return mdl;
+}
+
+static void _cx18_mdl_update_bufs_for_cpu(struct cx18_stream *s,
+                                          struct cx18_mdl *mdl)
+{
+        struct cx18_buffer *buf;
+        u32 buf_size = s->buf_size;
+        u32 bytesused = mdl->bytesused;
+
+        list_for_each_entry(buf, &mdl->buf_list, list) {
+                buf->readpos = 0;
+                if (bytesused >= buf_size) {
+                        buf->bytesused = buf_size;
+                        bytesused -= buf_size;
+                } else {
+                        buf->bytesused = bytesused;
+                        bytesused = 0;
+                }
+                cx18_buf_sync_for_cpu(s, buf);
+        }
+}
+
+static inline void cx18_mdl_update_bufs_for_cpu(struct cx18_stream *s,
+                                                struct cx18_mdl *mdl)
+{
+        struct cx18_buffer *buf;
+
+        if (list_is_singular(&mdl->buf_list)) {
+                buf = list_first_entry(&mdl->buf_list, struct cx18_buffer,
+                                       list);
+                buf->bytesused = mdl->bytesused;
+                buf->readpos = 0;
+                cx18_buf_sync_for_cpu(s, buf);
+        } else {
+                _cx18_mdl_update_bufs_for_cpu(s, mdl);
+        }
+}
+
+struct cx18_mdl *cx18_queue_get_mdl(struct cx18_stream *s, u32 id,
+        u32 bytesused)
+{
+        struct cx18 *cx = s->cx;
+        struct cx18_mdl *mdl;
+        struct cx18_mdl *tmp;
+        struct cx18_mdl *ret = NULL;
+        LIST_HEAD(sweep_up);
+
+        /*
+         * We don't have to acquire multiple q locks here, because we are
+         * serialized by the single threaded work handler.
+         * MDLs from the firmware will thus remain in order as
+         * they are moved from q_busy to q_full or to the dvb ring buffer.
+         */
+        spin_lock(&s->q_busy.lock);
+        list_for_each_entry_safe(mdl, tmp, &s->q_busy.list, list) {
+                /*
+                 * We should find what the firmware told us is done,
+                 * right at the front of the queue.  If we don't, we likely have
+                 * missed an mdl done message from the firmware.
+                 * Once we skip an mdl repeatedly, relative to the size of
+                 * q_busy, we have high confidence we've missed it.
+                 */
+                if (mdl->id != id) {
+                        mdl->skipped++;
+                        if (mdl->skipped >= atomic_read(&s->q_busy.depth)-1) {
+                                /* mdl must have fallen out of rotation */
+                                CX18_WARN("Skipped %s, MDL %d, %d "
+                                          "times - it must have dropped out of "
+                                          "rotation\n", s->name, mdl->id,
+                                          mdl->skipped);
+                                /* Sweep it up to put it back into rotation */
+                                list_move_tail(&mdl->list, &sweep_up);
+                                atomic_dec(&s->q_busy.depth);
+                        }
+                        continue;
+                }
+                /*
+                 * We pull the desired mdl off of the queue here.  Something
+                 * will have to put it back on a queue later.
+                 */
+                list_del_init(&mdl->list);
+                atomic_dec(&s->q_busy.depth);
+                ret = mdl;
+                break;
+        }
+        spin_unlock(&s->q_busy.lock);
+
+        /*
+         * We found the mdl for which we were looking.  Get it ready for
+         * the caller to put on q_full or in the dvb ring buffer.
+         */
+        if (ret != NULL) {
+                ret->bytesused = bytesused;
+                ret->skipped = 0;
+                /* 0'ed readpos, m_flags & curr_buf when mdl went on q_busy */
+                cx18_mdl_update_bufs_for_cpu(s, ret);
+                if (s->type != CX18_ENC_STREAM_TYPE_TS)
+                        set_bit(CX18_F_M_NEED_SWAP, &ret->m_flags);
+        }
+
+        /* Put any mdls the firmware is ignoring back into normal rotation */
+        list_for_each_entry_safe(mdl, tmp, &sweep_up, list) {
+                list_del_init(&mdl->list);
+                cx18_enqueue(s, mdl, &s->q_free);
+        }
+        return ret;
+}
+
+/* Move all mdls of a queue, while flushing the mdl */
+static void cx18_queue_flush(struct cx18_stream *s,
+                             struct cx18_queue *q_src, struct cx18_queue *q_dst)
+{
+        struct cx18_mdl *mdl;
+
+        /* It only makes sense to flush to q_free or q_idle */
+        if (q_src == q_dst || q_dst == &s->q_full || q_dst == &s->q_busy)
+                return;
+
+        spin_lock(&q_src->lock);
+        spin_lock(&q_dst->lock);
+        while (!list_empty(&q_src->list)) {
+                mdl = list_first_entry(&q_src->list, struct cx18_mdl, list);
+                list_move_tail(&mdl->list, &q_dst->list);
+                mdl->bytesused = 0;
+                mdl->readpos = 0;
+                mdl->m_flags = 0;
+                mdl->skipped = 0;
+                mdl->curr_buf = NULL;
+                atomic_inc(&q_dst->depth);
+        }
+        cx18_queue_init(q_src);
+        spin_unlock(&q_src->lock);
+        spin_unlock(&q_dst->lock);
+}
+
+void cx18_flush_queues(struct cx18_stream *s)
+{
+        cx18_queue_flush(s, &s->q_busy, &s->q_free);
+        cx18_queue_flush(s, &s->q_full, &s->q_free);
+}
+
+/*
+ * Note, s->buf_pool is not protected by a lock,
+ * the stream better not have *anything* going on when calling this
+ */
+void cx18_unload_queues(struct cx18_stream *s)
+{
+        struct cx18_queue *q_idle = &s->q_idle;
+        struct cx18_mdl *mdl;
+        struct cx18_buffer *buf;
+
+        /* Move all MDLS to q_idle */
+        cx18_queue_flush(s, &s->q_busy, q_idle);
+        cx18_queue_flush(s, &s->q_full, q_idle);
+        cx18_queue_flush(s, &s->q_free, q_idle);
+
+        /* Reset MDL id's and move all buffers back to the stream's buf_pool */
+        spin_lock(&q_idle->lock);
+        list_for_each_entry(mdl, &q_idle->list, list) {
+                while (!list_empty(&mdl->buf_list)) {
+                        buf = list_first_entry(&mdl->buf_list,
+                                               struct cx18_buffer, list);
+                        list_move_tail(&buf->list, &s->buf_pool);
+                        buf->bytesused = 0;
+                        buf->readpos = 0;
+                }
+                mdl->id = s->mdl_base_idx; /* reset id to a "safe" value */
+                /* all other mdl fields were cleared by cx18_queue_flush() */
+        }
+        spin_unlock(&q_idle->lock);
+}
+
+/*
+ * Note, s->buf_pool is not protected by a lock,
+ * the stream better not have *anything* going on when calling this
+ */
+void cx18_load_queues(struct cx18_stream *s)
+{
+        struct cx18 *cx = s->cx;
+        struct cx18_mdl *mdl;
+        struct cx18_buffer *buf;
+        int mdl_id;
+        int i;
+        u32 partial_buf_size;
+
+        /*
+         * Attach buffers to MDLs, give the MDLs ids, and add MDLs to q_free
+         * Excess MDLs are left on q_idle
+         * Excess buffers are left in buf_pool and/or on an MDL in q_idle
+         */
+        mdl_id = s->mdl_base_idx;
+        for (mdl = cx18_dequeue(s, &s->q_idle), i = s->bufs_per_mdl;
+             mdl != NULL && i == s->bufs_per_mdl;
+             mdl = cx18_dequeue(s, &s->q_idle)) {
+
+                mdl->id = mdl_id;
+
+                for (i = 0; i < s->bufs_per_mdl; i++) {
+                        if (list_empty(&s->buf_pool))
+                                break;
+
+                        buf = list_first_entry(&s->buf_pool, struct cx18_buffer,
+                                               list);
+                        list_move_tail(&buf->list, &mdl->buf_list);
+
+                        /* update the firmware's MDL array with this buffer */
+                        cx18_writel(cx, buf->dma_handle,
+                                    &cx->scb->cpu_mdl[mdl_id + i].paddr);
+                        cx18_writel(cx, s->buf_size,
+                                    &cx->scb->cpu_mdl[mdl_id + i].length);
+                }
+
+                if (i == s->bufs_per_mdl) {
+                        /*
+                         * The encoder doesn't honor s->mdl_size.  So in the
+                         * case of a non-integral number of buffers to meet
+                         * mdl_size, we lie about the size of the last buffer
+                         * in the MDL to get the encoder to really only send
+                         * us mdl_size bytes per MDL transfer.
+                         */
+                        partial_buf_size = s->mdl_size % s->buf_size;
+                        if (partial_buf_size) {
+                                cx18_writel(cx, partial_buf_size,
+                                      &cx->scb->cpu_mdl[mdl_id + i - 1].length);
+                        }
+                        cx18_enqueue(s, mdl, &s->q_free);
+                } else {
+                        /* Not enough buffers for this MDL; we won't use it */
+                        cx18_push(s, mdl, &s->q_idle);
+                }
+                mdl_id += i;
+        }
+}
+
+void _cx18_mdl_sync_for_device(struct cx18_stream *s, struct cx18_mdl *mdl)
+{
+        int dma = s->dma;
+        u32 buf_size = s->buf_size;
+        struct pci_dev *pci_dev = s->cx->pci_dev;
+        struct cx18_buffer *buf;
+
+        list_for_each_entry(buf, &mdl->buf_list, list)
+                pci_dma_sync_single_for_device(pci_dev, buf->dma_handle,
+                                               buf_size, dma);
+}
+
+int cx18_stream_alloc(struct cx18_stream *s)
+{
+        struct cx18 *cx = s->cx;
+        int i;
+
+        if (s->buffers == 0)
+                return 0;
+
+        CX18_DEBUG_INFO("Allocate %s stream: %d x %d buffers "
+                        "(%d.%02d kB total)\n",
+                s->name, s->buffers, s->buf_size,
+                s->buffers * s->buf_size / 1024,
+                (s->buffers * s->buf_size * 100 / 1024) % 100);
+
+        if (((char __iomem *)&cx->scb->cpu_mdl[cx->free_mdl_idx + s->buffers] -
+                                (char __iomem *)cx->scb) > SCB_RESERVED_SIZE) {
+                unsigned bufsz = (((char __iomem *)cx->scb) + SCB_RESERVED_SIZE -
+                                        ((char __iomem *)cx->scb->cpu_mdl));
+
+                CX18_ERR("Too many buffers, cannot fit in SCB area\n");
+                CX18_ERR("Max buffers = %zd\n",
+                        bufsz / sizeof(struct cx18_mdl_ent));
+                return -ENOMEM;
+        }
+
+        s->mdl_base_idx = cx->free_mdl_idx;
+
+        /* allocate stream buffers and MDLs */
+        for (i = 0; i < s->buffers; i++) {
+                struct cx18_mdl *mdl;
+                struct cx18_buffer *buf;
+
+                /* 1 MDL per buffer to handle the worst & also default case */
+                mdl = kzalloc(sizeof(struct cx18_mdl), GFP_KERNEL|__GFP_NOWARN);
+                if (mdl == NULL)
+                        break;
+
+                buf = kzalloc(sizeof(struct cx18_buffer),
+                                GFP_KERNEL|__GFP_NOWARN);
+                if (buf == NULL) {
+                        kfree(mdl);
+                        break;
+                }
+
+                buf->buf = kmalloc(s->buf_size, GFP_KERNEL|__GFP_NOWARN);
+                if (buf->buf == NULL) {
+                        kfree(mdl);
+                        kfree(buf);
+                        break;
+                }
+
+                INIT_LIST_HEAD(&mdl->list);
+                INIT_LIST_HEAD(&mdl->buf_list);
+                mdl->id = s->mdl_base_idx; /* a somewhat safe value */
+                cx18_enqueue(s, mdl, &s->q_idle);
+
+                INIT_LIST_HEAD(&buf->list);
+                buf->dma_handle = pci_map_single(s->cx->pci_dev,
+                                buf->buf, s->buf_size, s->dma);
+                cx18_buf_sync_for_cpu(s, buf);
+                list_add_tail(&buf->list, &s->buf_pool);
+        }
+        if (i == s->buffers) {
+                cx->free_mdl_idx += s->buffers;
+                return 0;
+        }
+        CX18_ERR("Couldn't allocate buffers for %s stream\n", s->name);
+        cx18_stream_free(s);
+        return -ENOMEM;
+}
+
+void cx18_stream_free(struct cx18_stream *s)
+{
+        struct cx18_mdl *mdl;
+        struct cx18_buffer *buf;
+        struct cx18 *cx = s->cx;
+
+        CX18_DEBUG_INFO("Deallocating buffers for %s stream\n", s->name);
+
+        /* move all buffers to buf_pool and all MDLs to q_idle */
+        cx18_unload_queues(s);
+
+        /* empty q_idle */
+        while ((mdl = cx18_dequeue(s, &s->q_idle)))
+                kfree(mdl);
+
+        /* empty buf_pool */
+        while (!list_empty(&s->buf_pool)) {
+                buf = list_first_entry(&s->buf_pool, struct cx18_buffer, list);
+                list_del_init(&buf->list);
+
+                pci_unmap_single(s->cx->pci_dev, buf->dma_handle,
+                                s->buf_size, s->dma);
+                kfree(buf->buf);
+                kfree(buf);
+        }
+}