On Sat, Feb 11, 2012 at 11:17 AM, Aguirre, Sergio <saagui...@ti.com> wrote:
> Hi Sakari,
>
> On Fri, Feb 10, 2012 at 2:32 PM, Sakari Ailus <sakari.ai...@iki.fi> wrote:
>> Hi Sergio,
>>
>> Thanks for the review!
>>
>> Aguirre, Sergio wrote:
>>> On Thu, Feb 2, 2012 at 5:54 PM, Sakari Ailus <sakari.ai...@iki.fi> wrote:
>>>> Configure CSI-2 phy based on platform data in the ISP driver. For that, the
>>>> new V4L2_CID_IMAGE_SOURCE_PIXEL_RATE control is used. Previously the same
>>>> was configured from the board code.
>>>>
>>>> Signed-off-by: Sakari Ailus <sakari.ai...@iki.fi>
>>>> ---
>>>>  drivers/media/video/omap3isp/ispcsi2.c   |   10 +++-
>>>>  drivers/media/video/omap3isp/ispcsiphy.c |   78 
>>>> ++++++++++++++++++++++++++----
>>>>  drivers/media/video/omap3isp/ispcsiphy.h |    2 +
>>>>  3 files changed, 78 insertions(+), 12 deletions(-)
>>>>
>>>> diff --git a/drivers/media/video/omap3isp/ispcsi2.c 
>>>> b/drivers/media/video/omap3isp/ispcsi2.c
>>>> index 9313f7c..e2e3d63 100644
>>>> --- a/drivers/media/video/omap3isp/ispcsi2.c
>>>> +++ b/drivers/media/video/omap3isp/ispcsi2.c
>>>> @@ -1068,7 +1068,13 @@ static int csi2_set_stream(struct v4l2_subdev *sd, 
>>>> int enable)
>>>>        struct isp_video *video_out = &csi2->video_out;
>>>>
>>>>        switch (enable) {
>>>> -       case ISP_PIPELINE_STREAM_CONTINUOUS:
>>>> +       case ISP_PIPELINE_STREAM_CONTINUOUS: {
>>>> +               int ret;
>>>> +
>>>> +               ret = omap3isp_csiphy_config(isp, sd);
>>>> +               if (ret < 0)
>>>> +                       return ret;
>>>> +
>>>>                if (omap3isp_csiphy_acquire(csi2->phy) < 0)
>>>>                        return -ENODEV;
>>>>                csi2->use_fs_irq = pipe->do_propagation;
>>>> @@ -1092,7 +1098,7 @@ static int csi2_set_stream(struct v4l2_subdev *sd, 
>>>> int enable)
>>>>                csi2_if_enable(isp, csi2, 1);
>>>>                isp_video_dmaqueue_flags_clr(video_out);
>>>>                break;
>>>> -
>>>> +       }
>>>>        case ISP_PIPELINE_STREAM_STOPPED:
>>>>                if (csi2->state == ISP_PIPELINE_STREAM_STOPPED)
>>>>                        return 0;
>>>> diff --git a/drivers/media/video/omap3isp/ispcsiphy.c 
>>>> b/drivers/media/video/omap3isp/ispcsiphy.c
>>>> index 5be37ce..5d7a6ab 100644
>>>> --- a/drivers/media/video/omap3isp/ispcsiphy.c
>>>> +++ b/drivers/media/video/omap3isp/ispcsiphy.c
>>>> @@ -28,6 +28,8 @@
>>>>  #include <linux/device.h>
>>>>  #include <linux/regulator/consumer.h>
>>>>
>>>> +#include "../../../../arch/arm/mach-omap2/control.h"
>>>> +
>>>>  #include "isp.h"
>>>>  #include "ispreg.h"
>>>>  #include "ispcsiphy.h"
>>>> @@ -138,15 +140,73 @@ static void csiphy_dphy_config(struct isp_csiphy 
>>>> *phy)
>>>>        isp_reg_writel(phy->isp, reg, phy->phy_regs, ISPCSIPHY_REG1);
>>>>  }
>>>>
>>>> -static int csiphy_config(struct isp_csiphy *phy,
>>>> -                        struct isp_csiphy_dphy_cfg *dphy,
>>>> -                        struct isp_csiphy_lanes_cfg *lanes)
>>>> +/*
>>>> + * TCLK values are OK at their reset values
>>>> + */
>>>> +#define TCLK_TERM      0
>>>> +#define TCLK_MISS      1
>>>> +#define TCLK_SETTLE    14
>>>> +
>>>> +int omap3isp_csiphy_config(struct isp_device *isp,
>>>> +                          struct v4l2_subdev *csi2_subdev)
>>>>  {
>>>> +       struct isp_csi2_device *csi2 = v4l2_get_subdevdata(csi2_subdev);
>>>> +       struct isp_pipeline *pipe = to_isp_pipeline(&csi2_subdev->entity);
>>>> +       struct isp_v4l2_subdevs_group *subdevs = pipe->external->host_priv;
>>>> +       struct isp_csiphy_dphy_cfg csi2phy;
>>>> +       int csi2_ddrclk_khz;
>>>> +       struct isp_csiphy_lanes_cfg *lanes;
>>>>        unsigned int used_lanes = 0;
>>>>        unsigned int i;
>>>>
>>>> +       if (subdevs->interface == ISP_INTERFACE_CCP2B_PHY1
>>>> +           || subdevs->interface == ISP_INTERFACE_CCP2B_PHY2)
>>>> +               lanes = &subdevs->bus.ccp2.lanecfg;
>>>> +       else
>>>> +               lanes = &subdevs->bus.csi2.lanecfg;
>>>> +
>>>> +       /* FIXME: Do 34xx / 35xx require something here? */
>>>> +       if (cpu_is_omap3630()) {
>>>> +               u32 cam_phy_ctrl = omap_readl(
>>>> +                       OMAP343X_CTRL_BASE + 
>>>> OMAP3630_CONTROL_CAMERA_PHY_CTRL);
>>>
>>> How about:
>>>               u32 cam_phy_ctrl = 
>>> omap_ctrl_readl(OMAP3630_CONTROL_CAMERA_PHY_CTRL);
>>> ?
>>
>> Fine for me.
>>
>>>> +
>>>> +               /*
>>>> +                * SCM.CONTROL_CAMERA_PHY_CTRL
>>>> +                * - bit[4]    : CSIPHY1 data sent to CSIB
>>>> +                * - bit [3:2] : CSIPHY1 config: 00 d-phy, 01/10 ccp2
>>>> +                * - bit [1:0] : CSIPHY2 config: 00 d-phy, 01/10 ccp2
>>>> +                */
>>>> +               if (subdevs->interface == ISP_INTERFACE_CCP2B_PHY1)
>>>> +                       cam_phy_ctrl |= 1 << 2;
>>>> +               else if (subdevs->interface == ISP_INTERFACE_CSI2C_PHY1)
>>>> +                       cam_phy_ctrl &= 1 << 2;
>>>
>>> Shouldn't this be:
>>>                        cam_phy_ctrl &= ~(1 << 2);
>>> ?
>>
>> Probably yes. This has come directly as it was in the original board
>> code and might not be entirely correct. It works on the N9 at least.
>>
>>>> +
>>>> +               if (subdevs->interface == ISP_INTERFACE_CCP2B_PHY2)
>>>> +                       cam_phy_ctrl |= 1;
>>>> +               else if (subdevs->interface == ISP_INTERFACE_CSI2A_PHY2)
>>>> +                       cam_phy_ctrl &= 1;
>>>
>>> ... and:
>>>                        cam_phy_ctrl &= ~1;
>>>
>>>> +
>>>> +               omap_writel(cam_phy_ctrl,
>>>> +                           OMAP343X_CTRL_BASE
>>>> +                           + OMAP3630_CONTROL_CAMERA_PHY_CTRL);
>>>
>>> Again:
>>>               omap_ctrl_writel(cam_phy_ctrl, 
>>> OMAP3630_CONTROL_CAMERA_PHY_CTRL);
>>
>> Will fix.
>>
>>>> +       }
>>>> +
>>>> +       csi2_ddrclk_khz = pipe->external_rate / 1000
>>>> +               / (2 * csi2->phy->num_data_lanes)
>>>> +               * pipe->external_bpp;
>>>
>>> Can you please explain how did you came up with this formula?
>>>
>>> For example, if I keep the pixel_rate, yet I change the number of
>>> lanes my sensor is using,
>>> this result is unaltered, as phy->num_data_lanes is always equal to
>>> the maximum number
>>> of lanes available in the interface. (for OMAP4, that's 4 datalanes for 
>>> CSI2-A).
>>
>> The number of lanes is specified in the board code (in the future, DT)
>> and is thus specific to the board. The clock rate is per-lane whereas
>> the pipe->external_rate is the total pixel rate on all lanes.
>>
>>> Meanwhile, in theory, if I keep the same pixels per second, and use
>>> less datalanes, the
>>> DDR frequency should at least double.
>>>
>>> Now, this brings me to another question, How can the sensor tell how many 
>>> lanes
>>> is using from the total?
>>
>> We might consider making the number of lanes used dynamic but that's
>> currently static. I can't think of any major benefits right now in
>> making this dynamically configurable.
>>
>> Does this answer to your questions? :-)
>
>
> Sorry, I think I didn't made my point clear properly, so I'm proposing
> a patch to
> expose and fix this wrong calculation i'm telling you about:
>
> <<<<<<<< PATCH START
> From: Sergio Aguirre <saagui...@ti.com>
> Date: Sat, 11 Feb 2012 10:53:01 -0600
> Subject: [PATCH] omap3isp: phy: get ddrclk based on sensor lanecount
>
> This will allow csi2_ddrclk_khz be calculated correctly, by
> observing the sensor lane count, and not the interface lane count.
>
> An example of erratic calculation is, if you have a sensor
> which only has 1 data lane for output, yet the interface has 2
> lanes available, the rate still is split in half:
>
> pixel_rate = 96000000
> bpp = 10
> sensor_data_lanes = 1
> phy_data_lanes = 2
>
> Current formula pretty much says:
>
> csi2_ddrclk_khz = pixel_rate / 1000
>                / (2 * phy_data_lanes)
>                * bpp;
>
> Explained is:
>
> bits/second(bps) = pixels/second(pixel_rate) * bits/pixel(bpp)
> cycles/second(Hz) = bits/second / 2 bits/cycle
> cycles/datalane = cycles/second / num
>
> Which is you use 2 in last line, would be wrong for a single
> datalane sensor, so this patch attemote to collect the sensor
> lane count, and use that instead in the formula.
>
> NOTE: This is tested on omap4iss driver, which is in development.
>
> Signed-off-by: Sergio Aguirre <saagui...@ti.com>
> ---
>  drivers/media/video/omap3isp/ispcsiphy.c |   41 
> ++++++++++++++++--------------
>  drivers/media/video/omap3isp/ispcsiphy.h |    3 +-
>  2 files changed, 24 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/media/video/omap3isp/ispcsiphy.c
> b/drivers/media/video/omap3isp/ispcsiphy.c
> index 5d7a6ab..03c5749 100644
> --- a/drivers/media/video/omap3isp/ispcsiphy.c
> +++ b/drivers/media/video/omap3isp/ispcsiphy.c
> @@ -47,7 +47,7 @@ static void csiphy_lanes_config(struct isp_csiphy *phy)
>
>        reg = isp_reg_readl(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG);
>
> -       for (i = 0; i < phy->num_data_lanes; i++) {
> +       for (i = 0; i < phy->max_data_lanes; i++) {
>                reg &= ~(ISPCSI2_PHY_CFG_DATA_POL_MASK(i + 1) |
>                         ISPCSI2_PHY_CFG_DATA_POSITION_MASK(i + 1));
>                reg |= (phy->lanes.data[i].pol <<
> @@ -191,22 +191,8 @@ int omap3isp_csiphy_config(struct isp_device *isp,
>                            + OMAP3630_CONTROL_CAMERA_PHY_CTRL);
>        }
>
> -       csi2_ddrclk_khz = pipe->external_rate / 1000
> -               / (2 * csi2->phy->num_data_lanes)
> -               * pipe->external_bpp;
> -
> -       /*
> -        * THS_TERM: Programmed value = ceil(12.5 ns/DDRClk period) - 1.
> -        * THS_SETTLE: Programmed value = ceil(90 ns/DDRClk period) + 3.
> -        */
> -       csi2phy.ths_term = DIV_ROUND_UP(25 * csi2_ddrclk_khz, 2000000) - 1;
> -       csi2phy.ths_settle = DIV_ROUND_UP(90 * csi2_ddrclk_khz, 1000000) + 3;
> -       csi2phy.tclk_term = TCLK_TERM;
> -       csi2phy.tclk_miss = TCLK_MISS;
> -       csi2phy.tclk_settle = TCLK_SETTLE;
> -
>        /* Clock and data lanes verification */
> -       for (i = 0; i < csi2->phy->num_data_lanes; i++) {
> +       for (i = 0; i < csi2->phy->max_data_lanes; i++) {
>                if (lanes->data[i].pol > 1 || lanes->data[i].pos > 3)
>                        return -EINVAL;
>
> @@ -214,14 +200,29 @@ int omap3isp_csiphy_config(struct isp_device *isp,
>                        return -EINVAL;
>
>                used_lanes |= 1 << lanes->data[i].pos;
> +               csi2->phy->used_data_lanes++;
>        }
>
> -       if (lanes->clk.pol > 1 || lanes->clk.pos > 3)
> +       if (lanes->clk.pol > 1 || lanes->clk.pos > csi2->phy->max_data_lanes)

Oops, above should be:

       if (lanes->clk.pol > 1 || lanes->clk.pos >
(csi2->phy->max_data_lanes + 1))

To correctly allow a position in between 1 and 3, as there's 3 lanes in total,
1 for clock and max_data_lanes for data.

Apologies for the confusion

Regards,
Sergio

>                return -EINVAL;
>
>        if (lanes->clk.pos == 0 || used_lanes & (1 << lanes->clk.pos))
>                return -EINVAL;
>
> +       csi2_ddrclk_khz = pipe->external_rate / 1000
> +               / (2 * csi2->phy->used_data_lanes)
> +               * pipe->external_bpp;
> +
> +       /*
> +        * THS_TERM: Programmed value = ceil(12.5 ns/DDRClk period) - 1.
> +        * THS_SETTLE: Programmed value = ceil(90 ns/DDRClk period) + 3.
> +        */
> +       csi2phy.ths_term = DIV_ROUND_UP(25 * csi2_ddrclk_khz, 2000000) - 1;
> +       csi2phy.ths_settle = DIV_ROUND_UP(90 * csi2_ddrclk_khz, 1000000) + 3;
> +       csi2phy.tclk_term = TCLK_TERM;
> +       csi2phy.tclk_miss = TCLK_MISS;
> +       csi2phy.tclk_settle = TCLK_SETTLE;
> +
>        mutex_lock(&csi2->phy->mutex);
>        csi2->phy->dphy = csi2phy;
>        csi2->phy->lanes = *lanes;
> @@ -287,7 +288,8 @@ int omap3isp_csiphy_init(struct isp_device *isp)
>
>        phy2->isp = isp;
>        phy2->csi2 = &isp->isp_csi2a;
> -       phy2->num_data_lanes = ISP_CSIPHY2_NUM_DATA_LANES;
> +       phy2->max_data_lanes = ISP_CSIPHY2_NUM_DATA_LANES;
> +       phy2->used_data_lanes = 0;
>        phy2->cfg_regs = OMAP3_ISP_IOMEM_CSI2A_REGS1;
>        phy2->phy_regs = OMAP3_ISP_IOMEM_CSIPHY2;
>        mutex_init(&phy2->mutex);
> @@ -295,7 +297,8 @@ int omap3isp_csiphy_init(struct isp_device *isp)
>        if (isp->revision == ISP_REVISION_15_0) {
>                phy1->isp = isp;
>                phy1->csi2 = &isp->isp_csi2c;
> -               phy1->num_data_lanes = ISP_CSIPHY1_NUM_DATA_LANES;
> +               phy1->max_data_lanes = ISP_CSIPHY1_NUM_DATA_LANES;
> +               phy1->used_data_lanes = 0;
>                phy1->cfg_regs = OMAP3_ISP_IOMEM_CSI2C_REGS1;
>                phy1->phy_regs = OMAP3_ISP_IOMEM_CSIPHY1;
>                mutex_init(&phy1->mutex);
> diff --git a/drivers/media/video/omap3isp/ispcsiphy.h
> b/drivers/media/video/omap3isp/ispcsiphy.h
> index a404b10..3401bbd 100644
> --- a/drivers/media/video/omap3isp/ispcsiphy.h
> +++ b/drivers/media/video/omap3isp/ispcsiphy.h
> @@ -51,7 +51,8 @@ struct isp_csiphy {
>        unsigned int cfg_regs;
>        unsigned int phy_regs;
>
> -       u8 num_data_lanes;      /* number of CSI2 Data Lanes supported */
> +       u8 max_data_lanes;      /* number of CSI2 Data Lanes supported */
> +       u8 used_data_lanes;     /* number of CSI2 Data Lanes used */
>        struct isp_csiphy_lanes_cfg lanes;
>        struct isp_csiphy_dphy_cfg dphy;
>  };
> --
> 1.7.7.4
>>>>>>>>> PATCH END
>
> I hope this clarifies my point.
>
> Regards,
> Sergio
>
>>
>> Kind regards,
>>
>> --
>> Sakari Ailus
>> sakari.ai...@iki.fi
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to