i.MX ProcessorsのトピックRe: Correct register value for RAW12 data reception

Correct register value for RAW12 data reception

t-sugiyama — Thu, 28 May 2020 07:47:59 GMT

Hello,
I want to receive RAW12 image data with MIPI-CSI and set the data to FB1 and FB2 with DMA of CSI Bridge.
However, I don't know the proper register settings for MIPI-CSI and CSI Bridge for RAW12.

1.TWO_8BIT_SENSOR
When TWO_8BIT_SENSOR is 0, it doesn't look like an image at all, but when TWO_8BIT_SENSOR is 1, it looks like an image.
(debayer is required separately)
Is 1 the right choice for TWO_8BIT_SENSOR in a RAW12 receiving environment?

2.BASEADDR_CHHANGE_ERROR
When receiving RAW12 and setting DMA1's FB1 and FB2 to be switched as follows, BASEADDR_CHHANGE_ERROR will occur and the data set will not be completed in FB1 and FB2.
CSI_CSICR18:BASEADDR_SWITCH_EN 1

With the following settings, the data will be set in FB1 and FB2, but the images cannot be synchronized well.
CSI_CSICR18:BASEADDR_SWITCH_EN 0

I would like to know if there is a missing setting for the above problem.

Since we are trying to acquire VGA size images with RAW12, we have made the following settings.
CSI_CSIIMAG_PARA:IMAGE_WIDTH　640
CSI_CSIIMAG_PARA:IMAGE_HEIGHT　480
CSI_CSICR18:MIPI_DATA_FORMAT　RAW12(0x2C)

Thanks.
Tetsuya.

Re: Correct register value for RAW12 data reception

joanxie — Mon, 01 Jun 2020 08:50:04 GMT

did you change anything in the bsp? try to add the source code as below in your bsp:

add #define BIT_MIPI_DATA_FORMAT_RAW12 (0x2C << 25 ) , and

add this code to the "struct mx6s_fmt formats"

{
        .name       = "RAWRGB12 (SGRBG12)",
        .fourcc       = V4L2_PIX_FMT_SGRBG12,
     .pixelformat   = V4L2_PIX_FMT_SGRBG12,
     .mbus_code   = MEDIA_BUS_FMT_SRGGB12_1X12,

.bpp = 1,
}

static int mx6s_configure_csi(struct mx6s_csi_dev *csi_dev)
    switch (csi_dev->fmt->pixelformat) {
    case V4L2_PIX_FMT_YUV32:
    case V4L2_PIX_FMT_SBGGR8:
+   case V4L2_PIX_FMT_SGRBG12:
        width = pix->width;
        break;
    case V4L2_PIX_FMT_UYVY:

static int mx6s_configure_csi(struct mx6s_csi_dev *csi_dev)
        case V4L2_PIX_FMT_SBGGR8:
            cr18 |= BIT_MIPI_DATA_FORMAT_RAW8;
            break;
+       case V4L2_PIX_FMT_SGRBG12:
+           cr18 |= BIT_MIPI_DATA_FORMAT_RAW12;
+           break;
        default:
            pr_debug("   fmt not supported\n");
            return -EINVAL;

pls set the bsp correct firstly

Re: Correct register value for RAW12 data reception

t-sugiyama — Mon, 01 Jun 2020 14:07:54 GMT

Hello joan,

Thanks for the answer.
I am trying to control MIPI-CSI with cortex-M4 of i.MX8Mmini to get RAW12 format image from camera.
However, when I control to get the RAW12 data, I am missing one pixel for every two pixels I get.
So I'm looking into the correct acquisition method of RAW12.
The reference manual does not contain much information on how to handle images in RAW12 format, so I believe that if the correct register value is known, investigation will proceed.
The source code information given to me by Joan is a hint to find the register settings for RAW12 format.

Best regards
Tetsuya