The way discard buffer was previously handled lead
to possible races that made a buffer that was not
yet ready to be overwritten by new video data. This
is easily detected at 25fps just adding "#define DEBUG"
to enable the "memset" check and seeing how the image
is corrupted.
A new "discard" queue and two discard buffers have
been added to make them flow trough the pipeline
of queues and thus provide suitable event ordering.
Signed-off-by: Javier Martin <javier.martin@xxxxxxxxxxxxxxxxx>
---
Changes since v2:
- Remove BUG_ON when active list is empty.
- Replace empty list checks with warnings.
---
drivers/media/video/mx2_camera.c | 280 +++++++++++++++++++++-----------------
1 files changed, 153 insertions(+), 127 deletions(-)
diff --git a/drivers/media/video/mx2_camera.c b/drivers/media/video/mx2_camera.c
index 35ab971..e7ccd97 100644
--- a/drivers/media/video/mx2_camera.c
+++ b/drivers/media/video/mx2_camera.c
@@ -237,7 +237,8 @@ struct mx2_buffer {
struct list_head queue;
enum mx2_buffer_state state;
- int bufnum;
+ int bufnum;
+ bool discard;
};
struct mx2_camera_dev {
@@ -256,6 +257,7 @@ struct mx2_camera_dev {
struct list_head capture;
struct list_head active_bufs;
+ struct list_head discard;
spinlock_t lock;
@@ -268,6 +270,7 @@ struct mx2_camera_dev {
u32 csicr1;
+ struct mx2_buffer buf_discard[2];
void *discard_buffer;
dma_addr_t discard_buffer_dma;
size_t discard_size;
@@ -329,6 +332,29 @@ static struct mx2_fmt_cfg *mx27_emma_prp_get_format(
return &mx27_emma_prp_table[0];
};
+static void mx27_update_emma_buf(struct mx2_camera_dev *pcdev,
+ unsigned long phys, int bufnum)
+{
+ struct mx2_fmt_cfg *prp = pcdev->emma_prp;
+
+ if (prp->cfg.channel == 1) {
+ writel(phys, pcdev->base_emma +
+ PRP_DEST_RGB1_PTR + 4 * bufnum);
+ } else {
+ writel(phys, pcdev->base_emma +
+ PRP_DEST_Y_PTR - 0x14 * bufnum);
+ if (prp->out_fmt == V4L2_PIX_FMT_YUV420) {
+ u32 imgsize = pcdev->icd->user_height *
+ pcdev->icd->user_width;
+
+ writel(phys + imgsize, pcdev->base_emma +
+ PRP_DEST_CB_PTR - 0x14 * bufnum);
+ writel(phys + ((5 * imgsize) / 4), pcdev->base_emma +
+ PRP_DEST_CR_PTR - 0x14 * bufnum);
+ }
+ }
+}
+
static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
{
unsigned long flags;
@@ -377,7 +403,7 @@ static int mx2_camera_add_device(struct soc_camera_device *icd)
writel(pcdev->csicr1, pcdev->base_csi + CSICR1);
pcdev->icd = icd;
- pcdev->frame_count = -1;
+ pcdev->frame_count = 0;
dev_info(icd->parent, "Camera driver attached to camera %d\n",
icd->devnum);
@@ -397,13 +423,6 @@ static void mx2_camera_remove_device(struct soc_camera_device *icd)
mx2_camera_deactivate(pcdev);
- if (pcdev->discard_buffer) {
- dma_free_coherent(ici->v4l2_dev.dev, pcdev->discard_size,
- pcdev->discard_buffer,
- pcdev->discard_buffer_dma);
- pcdev->discard_buffer = NULL;
- }
-
pcdev->icd = NULL;
}
@@ -640,7 +659,6 @@ static void mx2_videobuf_release(struct vb2_buffer *vb)
*/
spin_lock_irqsave(&pcdev->lock, flags);
- list_del_init(&buf->queue);
if (cpu_is_mx25() && buf->state == MX2_STATE_ACTIVE) {
if (pcdev->fb1_active == buf) {
pcdev->csicr1 &= ~CSICR1_FB1_DMA_INTEN;
@@ -656,6 +674,34 @@ static void mx2_videobuf_release(struct vb2_buffer *vb)
spin_unlock_irqrestore(&pcdev->lock, flags);
}
+static void mx27_camera_emma_buf_init(struct soc_camera_device *icd,
+ int bytesperline)
+{
+ struct soc_camera_host *ici =
+ to_soc_camera_host(icd->parent);
+ struct mx2_camera_dev *pcdev = ici->priv;
+ struct mx2_fmt_cfg *prp = pcdev->emma_prp;
+
+ writel((icd->user_width << 16) | icd->user_height,
+ pcdev->base_emma + PRP_SRC_FRAME_SIZE);
+ writel(prp->cfg.src_pixel,
+ pcdev->base_emma + PRP_SRC_PIXEL_FORMAT_CNTL);
+ if (prp->cfg.channel == 1) {
+ writel((icd->user_width << 16) | icd->user_height,
+ pcdev->base_emma + PRP_CH1_OUT_IMAGE_SIZE);
+ writel(bytesperline,
+ pcdev->base_emma + PRP_DEST_CH1_LINE_STRIDE);
+ writel(prp->cfg.ch1_pixel,
+ pcdev->base_emma + PRP_CH1_PIXEL_FORMAT_CNTL);
+ } else { /* channel 2 */
+ writel((icd->user_width << 16) | icd->user_height,
+ pcdev->base_emma + PRP_CH2_OUT_IMAGE_SIZE);
+ }
+
+ /* Enable interrupts */
+ writel(prp->cfg.irq_flags, pcdev->base_emma + PRP_INTR_CNTL);
+}
+
static int mx2_start_streaming(struct vb2_queue *q, unsigned int count)
{
struct soc_camera_device *icd = soc_camera_from_vb2q(q);
@@ -663,6 +709,10 @@ static int mx2_start_streaming(struct vb2_queue *q, unsigned int count)
to_soc_camera_host(icd->parent);
struct mx2_camera_dev *pcdev = ici->priv;
struct mx2_fmt_cfg *prp = pcdev->emma_prp;
+ struct vb2_buffer *vb;
+ struct mx2_buffer *buf;
+ unsigned long phys;
+ int bytesperline;
if (mx27_camera_emma(pcdev)) {
unsigned long flags;
@@ -670,6 +720,56 @@ static int mx2_start_streaming(struct vb2_queue *q, unsigned int count)
return -EINVAL;
spin_lock_irqsave(&pcdev->lock, flags);
+
+ buf = list_entry(pcdev->capture.next,
+ struct mx2_buffer, queue);
+ buf->bufnum = 0;
+ vb = &buf->vb;
+ buf->state = MX2_STATE_ACTIVE;
+
+ phys = vb2_dma_contig_plane_dma_addr(vb, 0);
+ mx27_update_emma_buf(pcdev, phys, buf->bufnum);
+ list_move_tail(pcdev->capture.next, &pcdev->active_bufs);
+
+ buf = list_entry(pcdev->capture.next,
+ struct mx2_buffer, queue);
+ buf->bufnum = 1;
+ vb = &buf->vb;
+ buf->state = MX2_STATE_ACTIVE;
+
+ phys = vb2_dma_contig_plane_dma_addr(vb, 0);
+ mx27_update_emma_buf(pcdev, phys, buf->bufnum);
+ list_move_tail(pcdev->capture.next, &pcdev->active_bufs);
+
+ bytesperline = soc_mbus_bytes_per_line(icd->user_width,
+ icd->current_fmt->host_fmt);
+ if (bytesperline < 0)
+ return bytesperline;
+
+ /*
+ * I didn't manage to properly enable/disable the prp
+ * on a per frame basis during running transfers,
+ * thus we allocate a buffer here and use it to
+ * discard frames when no buffer is available.
+ * Feel free to work on this ;)
+ */
+ pcdev->discard_size = icd->user_height * bytesperline;
+ pcdev->discard_buffer = dma_alloc_coherent(ici->v4l2_dev.dev,
+ pcdev->discard_size, &pcdev->discard_buffer_dma,
+ GFP_KERNEL);
+ if (!pcdev->discard_buffer)
+ return -ENOMEM;
+
+ pcdev->buf_discard[0].discard = true;
+ list_add_tail(&pcdev->buf_discard[0].queue,
+ &pcdev->discard);
+
+ pcdev->buf_discard[1].discard = true;
+ list_add_tail(&pcdev->buf_discard[1].queue,
+ &pcdev->discard);
+
+ mx27_camera_emma_buf_init(icd, bytesperline);
+
if (prp->cfg.channel == 1) {
writel(PRP_CNTL_CH1EN |
PRP_CNTL_CSIEN |
@@ -706,8 +806,9 @@ static int mx2_stop_streaming(struct vb2_queue *q)
unsigned long flags;
u32 cntl;
- spin_lock_irqsave(&pcdev->lock, flags);
if (mx27_camera_emma(pcdev)) {
+ spin_lock_irqsave(&pcdev->lock, flags);
+
cntl = readl(pcdev->base_emma + PRP_CNTL);
if (prp->cfg.channel == 1) {
writel(cntl & ~PRP_CNTL_CH1EN,
@@ -716,8 +817,18 @@ static int mx2_stop_streaming(struct vb2_queue *q)
writel(cntl & ~PRP_CNTL_CH2EN,
pcdev->base_emma + PRP_CNTL);
}
+ INIT_LIST_HEAD(&pcdev->capture);
+ INIT_LIST_HEAD(&pcdev->active_bufs);
+ INIT_LIST_HEAD(&pcdev->discard);
+
+ spin_unlock_irqrestore(&pcdev->lock, flags);
+
+ dma_free_coherent(ici->v4l2_dev.dev,
+ pcdev->discard_size, pcdev->discard_buffer,
+ pcdev->discard_buffer_dma);
+ pcdev->discard_buffer = NULL;
}
- spin_unlock_irqrestore(&pcdev->lock, flags);
+
return 0;
}
@@ -771,63 +882,6 @@ static int mx27_camera_emma_prp_reset(struct mx2_camera_dev *pcdev)
return -ETIMEDOUT;
}
-static void mx27_camera_emma_buf_init(struct soc_camera_device *icd,
- int bytesperline)
-{
- struct soc_camera_host *ici =
- to_soc_camera_host(icd->parent);
- struct mx2_camera_dev *pcdev = ici->priv;
- struct mx2_fmt_cfg *prp = pcdev->emma_prp;
- u32 imgsize = pcdev->icd->user_height * pcdev->icd->user_width;
-
- if (prp->cfg.channel == 1) {
- writel(pcdev->discard_buffer_dma,
- pcdev->base_emma + PRP_DEST_RGB1_PTR);
- writel(pcdev->discard_buffer_dma,
- pcdev->base_emma + PRP_DEST_RGB2_PTR);
-
- writel((icd->user_width << 16) | icd->user_height,
- pcdev->base_emma + PRP_SRC_FRAME_SIZE);
- writel((icd->user_width << 16) | icd->user_height,
- pcdev->base_emma + PRP_CH1_OUT_IMAGE_SIZE);
- writel(bytesperline,
- pcdev->base_emma + PRP_DEST_CH1_LINE_STRIDE);
- writel(prp->cfg.src_pixel,
- pcdev->base_emma + PRP_SRC_PIXEL_FORMAT_CNTL);
- writel(prp->cfg.ch1_pixel,
- pcdev->base_emma + PRP_CH1_PIXEL_FORMAT_CNTL);
- } else { /* channel 2 */
- writel(pcdev->discard_buffer_dma,
- pcdev->base_emma + PRP_DEST_Y_PTR);
- writel(pcdev->discard_buffer_dma,
- pcdev->base_emma + PRP_SOURCE_Y_PTR);
-
- if (prp->cfg.out_fmt == PRP_CNTL_CH2_OUT_YUV420) {
- writel(pcdev->discard_buffer_dma + imgsize,
- pcdev->base_emma + PRP_DEST_CB_PTR);
- writel(pcdev->discard_buffer_dma + ((5 * imgsize) / 4),
- pcdev->base_emma + PRP_DEST_CR_PTR);
- writel(pcdev->discard_buffer_dma + imgsize,
- pcdev->base_emma + PRP_SOURCE_CB_PTR);
- writel(pcdev->discard_buffer_dma + ((5 * imgsize) / 4),
- pcdev->base_emma + PRP_SOURCE_CR_PTR);
- }
-
- writel((icd->user_width << 16) | icd->user_height,
- pcdev->base_emma + PRP_SRC_FRAME_SIZE);
-
- writel((icd->user_width << 16) | icd->user_height,
- pcdev->base_emma + PRP_CH2_OUT_IMAGE_SIZE);
-
- writel(prp->cfg.src_pixel,
- pcdev->base_emma + PRP_SRC_PIXEL_FORMAT_CNTL);
-
- }
-
- /* Enable interrupts */
- writel(prp->cfg.irq_flags, pcdev->base_emma + PRP_INTR_CNTL);
-}
-
static int mx2_camera_set_bus_param(struct soc_camera_device *icd,
__u32 pixfmt)
{
@@ -911,27 +965,6 @@ static int mx2_camera_set_bus_param(struct soc_camera_device *icd,
ret = mx27_camera_emma_prp_reset(pcdev);
if (ret)
return ret;
-
- if (pcdev->discard_buffer)
- dma_free_coherent(ici->v4l2_dev.dev,
- pcdev->discard_size, pcdev->discard_buffer,
- pcdev->discard_buffer_dma);
-
- /*
- * I didn't manage to properly enable/disable the prp
- * on a per frame basis during running transfers,
- * thus we allocate a buffer here and use it to
- * discard frames when no buffer is available.
- * Feel free to work on this ;)
- */
- pcdev->discard_size = icd->user_height * bytesperline;
- pcdev->discard_buffer = dma_alloc_coherent(ici->v4l2_dev.dev,
- pcdev->discard_size, &pcdev->discard_buffer_dma,
- GFP_KERNEL);
- if (!pcdev->discard_buffer)
- return -ENOMEM;
-
- mx27_camera_emma_buf_init(icd, bytesperline);
} else if (cpu_is_mx25()) {
writel((bytesperline * icd->user_height) >> 2,
pcdev->base_csi + CSIRXCNT);
@@ -1179,18 +1212,23 @@ static struct soc_camera_host_ops mx2_soc_camera_host_ops = {
static void mx27_camera_frame_done_emma(struct mx2_camera_dev *pcdev,
int bufnum)
{
- u32 imgsize = pcdev->icd->user_height * pcdev->icd->user_width;
struct mx2_fmt_cfg *prp = pcdev->emma_prp;
struct mx2_buffer *buf;
struct vb2_buffer *vb;
unsigned long phys;
- if (!list_empty(&pcdev->active_bufs)) {
- buf = list_entry(pcdev->active_bufs.next,
- struct mx2_buffer, queue);
+ buf = list_entry(pcdev->active_bufs.next,
+ struct mx2_buffer, queue);
- BUG_ON(buf->bufnum != bufnum);
+ BUG_ON(buf->bufnum != bufnum);
+ if (buf->discard) {
+ /*
+ * Discard buffer must not be returned to user space.
+ * Just return it to the discard queue.
+ */
+ list_move_tail(pcdev->active_bufs.next, &pcdev->discard);
+ } else {
vb = &buf->vb;
#ifdef DEBUG
phys = vb2_dma_contig_plane_dma_addr(vb, 0);
@@ -1212,6 +1250,7 @@ static void mx27_camera_frame_done_emma(struct mx2_camera_dev *pcdev,
}
}
#endif
+
dev_dbg(pcdev->dev, "%s (vb=0x%p) 0x%p %lu\n", __func__, vb,
vb2_plane_vaddr(vb, 0),
vb2_get_plane_payload(vb, 0));
@@ -1225,29 +1264,23 @@ static void mx27_camera_frame_done_emma(struct mx2_camera_dev *pcdev,
pcdev->frame_count++;
if (list_empty(&pcdev->capture)) {
- if (prp->cfg.channel == 1) {
- writel(pcdev->discard_buffer_dma, pcdev->base_emma +
- PRP_DEST_RGB1_PTR + 4 * bufnum);
- } else {
- writel(pcdev->discard_buffer_dma, pcdev->base_emma +
- PRP_DEST_Y_PTR -
- 0x14 * bufnum);
- if (prp->out_fmt == V4L2_PIX_FMT_YUV420) {
- writel(pcdev->discard_buffer_dma + imgsize,
- pcdev->base_emma + PRP_DEST_CB_PTR -
- 0x14 * bufnum);
- writel(pcdev->discard_buffer_dma +
- ((5 * imgsize) / 4), pcdev->base_emma +
- PRP_DEST_CR_PTR - 0x14 * bufnum);
- }
- }
+ if (list_empty(&pcdev->discard))
+ dev_warn(pcdev->dev, "%s: trying to access empty discard list\n",
+ __func__);
+
+ buf = list_entry(pcdev->discard.next,
+ struct mx2_buffer, queue);
+ buf->bufnum = bufnum;
+
+ list_move_tail(pcdev->discard.next, &pcdev->active_bufs);
+ mx27_update_emma_buf(pcdev, pcdev->discard_buffer_dma, bufnum);
return;
}
buf = list_entry(pcdev->capture.next,
struct mx2_buffer, queue);
- buf->bufnum = !bufnum;
+ buf->bufnum = bufnum;
list_move_tail(pcdev->capture.next, &pcdev->active_bufs);
@@ -1255,18 +1288,7 @@ static void mx27_camera_frame_done_emma(struct mx2_camera_dev *pcdev,
buf->state = MX2_STATE_ACTIVE;
phys = vb2_dma_contig_plane_dma_addr(vb, 0);
- if (prp->cfg.channel == 1) {
- writel(phys, pcdev->base_emma + PRP_DEST_RGB1_PTR + 4 * bufnum);
- } else {
- writel(phys, pcdev->base_emma +
- PRP_DEST_Y_PTR - 0x14 * bufnum);
- if (prp->cfg.out_fmt == PRP_CNTL_CH2_OUT_YUV420) {
- writel(phys + imgsize, pcdev->base_emma +
- PRP_DEST_CB_PTR - 0x14 * bufnum);
- writel(phys + ((5 * imgsize) / 4), pcdev->base_emma +
- PRP_DEST_CR_PTR - 0x14 * bufnum);
- }
- }
+ mx27_update_emma_buf(pcdev, phys, bufnum);
}
static irqreturn_t mx27_camera_emma_irq(int irq_emma, void *data)
@@ -1275,6 +1297,10 @@ static irqreturn_t mx27_camera_emma_irq(int irq_emma, void *data)
unsigned int status = readl(pcdev->base_emma + PRP_INTRSTATUS);
struct mx2_buffer *buf;
+ if (list_empty(&pcdev->active_bufs))
+ dev_warn(pcdev->dev, "%s: called while active list is empty\n",
+ __func__);
+
if (status & (1 << 7)) { /* overflow */
u32 cntl;
/*
@@ -1290,9 +1316,8 @@ static irqreturn_t mx27_camera_emma_irq(int irq_emma, void *data)
pcdev->base_emma + PRP_CNTL);
writel(cntl, pcdev->base_emma + PRP_CNTL);
}
- if ((((status & (3 << 5)) == (3 << 5)) ||
- ((status & (3 << 3)) == (3 << 3)))
- && !list_empty(&pcdev->active_bufs)) {
+ if (((status & (3 << 5)) == (3 << 5)) ||
+ ((status & (3 << 3)) == (3 << 3))) {
/*
* Both buffers have triggered, process the one we're expecting
* to first
@@ -1418,6 +1443,7 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
INIT_LIST_HEAD(&pcdev->capture);
INIT_LIST_HEAD(&pcdev->active_bufs);
+ INIT_LIST_HEAD(&pcdev->discard);
spin_lock_init(&pcdev->lock);
/*
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
