On Wed, Nov 20, 2019 at 5:11 PM Jerry-ch Chen
<Jerry-ch.Chen@xxxxxxxxxxxx> wrote:
>
> Hi Tomasz,
>
> On Fri, 2019-10-25 at 11:52 +0800, Tomasz Figa wrote:
> > On Tue, Oct 15, 2019 at 11:16:15AM +0800, Jerry-ch Chen wrote:
> > > Hi Tomasz,
> > >
> > > On Fri, 2019-09-06 at 18:11 +0800, Jerry-ch Chen wrote:
> > > > From: Jerry-ch Chen <jerry-ch.chen@xxxxxxxxxxxx>
> > > >
> > > > This patch adds the driver of Face Detection (FD) unit in
> > > > Mediatek camera system, providing face detection function.
> > > >
> > > > The mtk-isp directory will contain drivers for multiple IP
> > > > blocks found in Mediatek ISP system. It will include ISP Pass 1
> > > > driver (CAM), sensor interface driver, DIP driver and face
> > > > detection driver.
> > > >
> > > > Signed-off-by: Jerry-ch Chen <jerry-ch.chen@xxxxxxxxxxxx>
> > > > ---
> > > > drivers/media/platform/Kconfig | 2 +
> > > > drivers/media/platform/Makefile | 2 +
> > > > drivers/media/platform/mtk-isp/fd/Kconfig | 19 +
> > > > drivers/media/platform/mtk-isp/fd/Makefile | 5 +
> > > > drivers/media/platform/mtk-isp/fd/mtk_fd.h | 148 ++
> > > > drivers/media/platform/mtk-isp/fd/mtk_fd_40.c | 1219 +++++++++++++++++
> > > > include/uapi/linux/mtk-fd-v4l2-controls.h | 69 +
> > > > include/uapi/linux/v4l2-controls.h | 4 +
> > > > 8 files changed, 1468 insertions(+)
> > > > create mode 100644 drivers/media/platform/mtk-isp/fd/Kconfig
> > > > create mode 100644 drivers/media/platform/mtk-isp/fd/Makefile
> > > > create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd.h
> > > > create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd_40.c
> > > > create mode 100644 include/uapi/linux/mtk-fd-v4l2-controls.h
> > > >
> >
> > [snip]
> >
> > > > +static int mtk_fd_job_abort(struct mtk_fd_dev *fd)
> > > > +{
> > > > + u32 ret;
> > > > +
> > > > + ret = wait_for_completion_timeout(&fd->fd_irq_done,
> > > > + msecs_to_jiffies(MTK_FD_HW_TIMEOUT));
> > > > + /* Reset FD HW */
> > > > + if (!ret) {
> > > > + struct ipi_message fd_ipi_msg;
> > > > +
> > > > + fd_ipi_msg.cmd_id = MTK_FD_IPI_CMD_RESET;
> > > > + if (scp_ipi_send(fd->scp_pdev, SCP_IPI_FD_CMD, &fd_ipi_msg,
> > > > + sizeof(fd_ipi_msg), MTK_FD_IPI_SEND_TIMEOUT))
> > > > + dev_err(fd->dev, "FD Reset HW error\n");
> > > > + return -ETIMEDOUT;
> > > > + }
> > > > + return 0;
> > > > +}
> > > > +
> > >
> > > Continue the discussion about job abort in RFC v2,
> > >
> > > I think the job_abort callback in v4l2_m2m_ops() might be useful.
> > >
> > > ref:
> > > https://elixir.bootlin.com/linux/v5.4-rc2/source/drivers/media/v4l2-core/v4l2-mem2mem.c#L398
> > > https://elixir.bootlin.com/linux/v5.4-rc2/source/include/media/v4l2-mem2mem.h#L43
> > >
> > > in drivers/media/v4l2-core/v4l2-mem2mem.c #398 v4l2_m2m_cancel_job()
> > > ...
> > > if (m2m_ctx->job_flags & TRANS_RUNNING) {
> > > spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
> > > if (m2m_dev->m2m_ops->job_abort)
> > > m2m_dev->m2m_ops->job_abort(m2m_ctx->priv);
> > > dprintk("m2m_ctx %p running, will wait to complete\n", m2m_ctx);
> > > wait_event(m2m_ctx->finished,
> > > !(m2m_ctx->job_flags & TRANS_RUNNING));
> > > } ...
> > >
> > > If this operation is set, we might use the v4l2_m2m_cancel_job() when
> > > suspend, and it will do mtk_fd_job_abort() here.
> > >
> >
> > The expectation for .job_abort() is that signals the hardware to
> > instantly abandon the current job. Do we have a way to tell the
> > firmware/hardware to do so?
> >
> > Also, suspend must not abort the current job. Anything that was already
> > running is expected to complete successfuly and further jobs should
> > continue executing once the system resumes.
> >
> I appreciate your comments and Pi-Hsun's patch,
>
> Ok, I see.
> For FD40, we can't tell the firmware/hardware to instantly abandon the
> current job.
> Therefore, for suspend, we stop sending further jobs to hardware and
> wait for the completion of the running job.
> For resume, we continue sending jobs to hardware.
>
> > [snip]
> >
> > > > +
> > > > +static int mtk_fd_suspend(struct device *dev)
> > > > +{
> > > > + struct mtk_fd_dev *fd = dev_get_drvdata(dev);
> > > > +
> > > > + if (pm_runtime_suspended(dev))
> > > > + return 0;
> > > > +
> > > > + if (fd->fd_stream_count)
> > > > + if (mtk_fd_job_abort(fd))
> > > > + mtk_fd_hw_job_finish(fd, VB2_BUF_STATE_ERROR);
> > > > +
> > >
> > > To avoid mtk_fd_hw_job_finish() trigger the next job,
> > > I suppose that we could use v4l2_m2m_cancel_job instead of job_abort and
> > > job_finish here.
> > >
> > > /**
> > > * v4l2_m2m_cancel_job() - cancel pending jobs for the context
> > > * @m2m_ctx: m2m context with jobs to be canceled
> > > *
> > > * In case of streamoff or release called on any context,
> > > * 1] If the context is currently running, then abort job will be called
> > > * 2] If the context is queued, then the context will be removed from
> > > * the job_queue
> > > */
> > >
> > > or another way,
> > > we may add a flag and implement mtk_fd_job_ready() that reads the flag
> > > if we suspend, we set the flag and do job_abort and job_finish, even if
> > > it try enqueue, it will still not really queue the job, until we reset
> > > the flag in mtk_fd_resume().
> > >
> > > how do you think?
> > >
> >
> > As per my comment above, suspend must just pause the execution of the
> > jobs. It must not cause any jobs to be skipped.
> >
> > After analyzing the m2m framework and existing m2m drivers I realized
> > that they currently provide no way to correctly handle suspend/resume.
> > Pi-Hsun has been looking into fixing this in crrev.com/c/1878112 and
> > we'll send it upstream as soon as we get something that should handle
> > all the cases correctly.
> >
> Ok, thanks for the patches.
>
> > > > + /* suspend FD HW */
> > > > + writel(0x0, fd->fd_base + MTK_FD_REG_OFFSET_INT_EN);
> > > > + writel(0x0, fd->fd_base + MTK_FD_REG_OFFSET_HW_ENABLE);
> > > > + clk_disable_unprepare(fd->fd_clk);
> > > > + dev_dbg(dev, "%s:disable clock\n", __func__);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int mtk_fd_resume(struct device *dev)
> > > > +{
> > > > + struct mtk_fd_dev *fd = dev_get_drvdata(dev);
> > > > + int ret;
> > > > +
> > > > + if (pm_runtime_suspended(dev))
> > > > + return 0;
> > > > +
> > > > + ret = clk_prepare_enable(fd->fd_clk);
> > > > + if (ret < 0) {
> > > > + dev_dbg(dev, "Failed to open fd clk:%d\n", ret);
> > > > + return ret;
> > > > + }
> > > > +
> > > > + /* resume FD HW */
> > > > + writel(MTK_FD_SET_HW_ENABLE, fd->fd_base + MTK_FD_REG_OFFSET_HW_ENABLE);
> > > > + writel(0x1, fd->fd_base + MTK_FD_REG_OFFSET_INT_EN);
> > > > + dev_dbg(dev, "%s:enable clock\n", __func__);
> >
> > By the way, we need to kick the m2m framework here to schedule further
> > jobs. Pi-Hsun's patch will also take care of this.
> >
> Ok, I see.
> I would like to use Pi-Hsun's patch, otherwise I would need to call
> v4l2_m2m_try_run() here.
>
Yes, please include Pi-Hsun's patch (with original author, sign-off +
your sign-off added) at the beginning of the next version of your
series.
> > [snip]
> >
> > > > +/* Set the face angle and directions to be detected */
> > > > +#define V4L2_CID_MTK_FD_DETECT_POSE (V4L2_CID_USER_MTK_FD_BASE + 1)
> > > > +
> > > > +/* Set image widths for an input image to be scaled down for face detection */
> > > > +#define V4L2_CID_MTK_FD_SCALE_DOWN_IMG_WIDTH (V4L2_CID_USER_MTK_FD_BASE + 2)
> > > > +
> > > > +/* Set image heights for an input image to be scaled down for face detection */
> > > > +#define V4L2_CID_MTK_FD_SCALE_DOWN_IMG_HEIGHT (V4L2_CID_USER_MTK_FD_BASE + 3)
> > > > +
> > > > +/* Set the length of scale down size array */
> > > > +#define V4L2_CID_MTK_FD_SCALE_IMG_NUM (V4L2_CID_USER_MTK_FD_BASE + 4)
> > > > +
> > > > +/* Set the detection speed, usually reducing accuracy. */
> > > > +#define V4L2_CID_MTK_FD_DETECT_SPEED (V4L2_CID_USER_MTK_FD_BASE + 5)
> > > > +
> > > > +/* Select the detection model or algorithm to be used. */
> > > > +#define V4L2_CID_MTK_FD_DETECTION_MODEL (V4L2_CID_USER_MTK_FD_BASE + 6)
> > > > +
> > > > +/* We reserve 16 controls for this driver. */
> > > > +#define V4L2_CID_MTK_FD_MAX 16
> > > > +
> > >
> > > For these control IDs, I think the following should be remained as chip
> > > specific controls.
> > > V4L2_CID_MTK_FD_SCALE_DOWN_IMG_WIDTH,
> > > V4L2_CID_MTK_FD_SCALE_DOWN_IMG_HEIGHT and V4L2_CID_MTK_FD_SCALE_IMG_NUM
> > >
> > > Hope there would be standardizing face detection api that cover the rest
> > > controls: V4L2_CID_MTK_FD_DETECT_POSE, V4L2_CID_MTK_FD_DETECT_SPEED and
> > > V4L2_CID_MTK_FD_DETECTION_MODEL
> > >
> > > Would you have any suggestions on how to propose the standard face
> > > detection apis?
> > >
> >
> > Given no follow up feedback from the community, I think we can keep them
> > as driver-specific, but should make sure that they have some reasonable
> > default values in case an application doesn't recognize them.
> >
> > Best regards,
> > Tomasz
> >
> Should I keep the file "mtk-fd-v4l2-controls.h" which defines the
> control ids under the folder "/include/uapi/linux"?
We should define the CID base for the FD driver in v4l2-controls.h,
but the controls themselves should be only defined inside the driver.
For example:
https://elixir.bootlin.com/linux/v5.4-rc8/source/include/uapi/linux/v4l2-controls.h#L178
https://elixir.bootlin.com/linux/v5.4-rc8/source/drivers/media/i2c/adv7180.c#L181
Best regards,
Tomasz
