Hello,
> as the subject says I got a problem with the ccdc.
>
> My pipeline is: sensor -> ccdc -> memory
>
> By doing some research I found a appropriate answer from Laurent:
>
> "The OMAP3 ISP is quite picky about its input signals and doesn't gracefully
> handle missing or extra sync pulses for instance. A "CCDC won't become idle!"
> message usually indicates that the CCDC received a frame of unexpected size
> (this can happen if the sensor stops in the middle of a frame for instance),
> or that the driver had no time to process the end of frame interrupt before
> the next frame arrived (either because of an unsually long interrupt delay on
> the system, or because of too low vertical blanking)."
>
> That sounds logical, but whatever I do nothing works for me.
>
> Can anyone who had that problem share what you did to solve that problem?
> Or does anyone have a hint for me how to solve this?
I think I've stumbled upon a solution for this problem (stream doesn't
start properly, resulting in 'CCDC won't become idle') today; the idea is
to delay ccdc_enable() and SYN_MODE_VDHDEN after the first VSYNC has been
received
the assumption is that the ov3640 outputs HSYNC/VSYNC in some
weird/undeterministic way when started, but stabilizes afterwards; the
OMAP3 ISP gets confused by inproper HSYNC/VSYNC and never recovers...
OMAP3 ISP observations:
SYN_MODE_VDHDEN enables the VSYNC/HSYNC processing of the CCDC (when
VSYNC/HSYNC configured as input) of the ISP, i.e. the ISP starts counting
horizontal lines needed to trigger VDINT0/VDINT1
the VS_HS_IRQ can be configured to trigger on VSYNC, this is independent
from SYN_MODE_VDHDEN and VDINT0/VDINT1 and works even when neither
SYN_MODE_VDHDEN nor CCDC_PCR_EN is set (i.e. before starting the CCDC)
so ccdc_hs_vs_isr() can be used to trigger on the first (maybe n-th) VSYNC
(when the ov3640 has stabilized); at this point SYN_MODE_VDHDEN and
CCDC_PCR_EN can be turn on
so the workflow is as follows:
1. configure ISP: ccdc_set_stream() but no ccdc_enable() and no
SYN_MODE_VDHDEN
2. start ov3640: ov3640_set_stream()
3. wait for VSYNC to trigger, enable SYN_MODE_VDHDEN and ccdc_enable() in
ccdc_hs_vs_isr()
works for me :)
tested with beagle-xm, ov3640 (Laurent's patches) in YUV 640x480, ISP
direct to memory, kernel 3.7
the patch below illustrates this
regards, p.
diff --git a/drivers/media/platform/omap3isp/ispccdc.c b/drivers/media/platform/omap3isp/ispccdc.c
index aa9df9d..7d587ee 100644
--- a/drivers/media/platform/omap3isp/ispccdc.c
+++ b/drivers/media/platform/omap3isp/ispccdc.c
@@ -976,7 +976,8 @@ static void ccdc_config_sync_if(struct isp_ccdc_device *ccdc,
{
struct isp_device *isp = to_isp_device(ccdc);
const struct v4l2_mbus_framefmt *format;
- u32 syn_mode = ISPCCDC_SYN_MODE_VDHDEN;
+ u32 syn_mode = 0; // ISPCCDC_SYN_MODE_VDHDEN;
+ ccdc->vdhden = 0;
format = &ccdc->formats[CCDC_PAD_SINK];
@@ -1416,9 +1417,19 @@ static int __ccdc_handle_stopping(struct isp_ccdc_device *ccdc, u32 event)
static void ccdc_hs_vs_isr(struct isp_ccdc_device *ccdc)
{
struct isp_pipeline *pipe = to_isp_pipeline(&ccdc->subdev.entity);
+ struct isp_device *isp = to_isp_device(ccdc);
struct video_device *vdev = ccdc->subdev.devnode;
struct v4l2_event event;
+ if (!ccdc->vdhden) {
+ isp_reg_set(isp, OMAP3_ISP_IOMEM_CCDC, ISPCCDC_SYN_MODE,
+ ISPCCDC_SYN_MODE_VDHDEN);
+ ccdc_enable(ccdc);
+ ccdc->vdhden = 1;
+
+ return;
+ }
+
/* Frame number propagation */
atomic_inc(&pipe->frame_number);
@@ -1765,8 +1776,9 @@ static int ccdc_set_stream(struct v4l2_subdev *sd, int enable)
if (ccdc->output & CCDC_OUTPUT_MEMORY)
omap3isp_sbl_enable(isp, OMAP3_ISP_SBL_CCDC_WRITE);
- if (ccdc->underrun || !(ccdc->output & CCDC_OUTPUT_MEMORY))
- ccdc_enable(ccdc);
+ if (ccdc->underrun || !(ccdc->output & CCDC_OUTPUT_MEMORY)) {
+// ccdc_enable(ccdc);
+ }
ccdc->underrun = 0;
break;
diff --git a/drivers/media/platform/omap3isp/ispccdc.h b/drivers/media/platform/omap3isp/ispccdc.h
index a5da9e1..a502bc3 100644
--- a/drivers/media/platform/omap3isp/ispccdc.h
+++ b/drivers/media/platform/omap3isp/ispccdc.h
@@ -146,6 +146,7 @@ struct isp_ccdc_device {
struct ispccdc_lsc lsc;
unsigned int update;
unsigned int shadow_update;
+ unsigned int vdhden;
unsigned int underrun:1;
enum isp_pipeline_stream_state state;
--
Peter Meerwald
+43-664-2444418 (mobile)
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