Re: [PATCH 02/17] media: atomisp: pci: fix punit_ddr_dvfs_enable() argument for mrfld_power up case

Tsuchiya Yuto
2021-12-01T12:07:30Z

On Wed, 2021-10-20 at 22:25 +0900, Tsuchiya Yuto wrote:
> On Mon, 2021-10-18 at 14:07 +0300, Andy Shevchenko wrote:
> > On Mon, Oct 18, 2021 at 01:19:42AM +0900, Tsuchiya Yuto wrote:
> > > When comparing with intel-aero atomisp [1], it looks like
> > > punit_ddr_dvfs_enable() should take `false` as an argument on mrfld_power
> > > up case.
> > >
> > > Code from the intel-aero kernel [1]:
> > >
> > > int atomisp_mrfld_power_down(struct atomisp_device *isp)
> > > {
> > > [...]
> > > /*WA:Enable DVFS*/
> > > if (IS_CHT)
> > > punit_ddr_dvfs_enable(true);
> > >
> > > int atomisp_mrfld_power_up(struct atomisp_device *isp)
> > > {
> > > [...]
> > > /*WA for PUNIT, if DVFS enabled, ISP timeout observed*/
> > > if (IS_CHT)
> > > punit_ddr_dvfs_enable(false);
> > >
> > > This patch fixes the inverted argument as per the intel-aero code, as
> > > well as its comment. While here, fix space issues for comments in
> > > atomisp_mrfld_power().
> > >
> > > Note that it does not seem to be possible to unify the up/down cases for
> > > punit_ddr_dvfs_enable(), i.e., we can't do something like the following:
> > >
> > > if (IS_CHT)
> > > punit_ddr_dvfs_enable(!enable);
> > >
> > > because according to the intel-aero code [1], the DVFS is disabled
> > > before "writing 0x0 to ISPSSPM0 bit[1:0]" and the DVFS is enabled after
> > > "writing 0x3 to ISPSSPM0 bit[1:0]".
> > >
> > > [1] https://github.com/intel-aero/linux-kernel/blob/a1b673258feb915268377275130c5c5df0eafc82/drivers/media/pci/atomisp/atomisp_driver/atomisp_v4l2.c#L431-L514
> > >
> > > Fixes: 0f441fd70b1e ("media: atomisp: simplify the power down/up code")
> > > Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
> > > ---
> > > drivers/staging/media/atomisp/pci/atomisp_v4l2.c | 8 ++++----
> > > 1 file changed, 4 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/staging/media/atomisp/pci/atomisp_v4l2.c b/drivers/staging/media/atomisp/pci/atomisp_v4l2.c
> > > index 0511c454e769..f5362554638e 100644
> > > --- a/drivers/staging/media/atomisp/pci/atomisp_v4l2.c
> > > +++ b/drivers/staging/media/atomisp/pci/atomisp_v4l2.c
> > > @@ -711,15 +711,15 @@ static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable)
> > >
> > > dev_dbg(isp->dev, "IUNIT power-%s.\n", enable ? "on" : "off");
> > >
> > > - /*WA:Enable DVFS*/
> > > + /* WA for PUNIT, if DVFS enabled, ISP timeout observed */
> >
> > P-Unit
>
> Thanks, I'll fix this next time I send.

For the record, this is already fixed in the latest media_stage tree.

> > > if (IS_CHT && enable)
> > > - punit_ddr_dvfs_enable(true);
> > > + punit_ddr_dvfs_enable(false);
> > >
> > > /*
> > > * FIXME:WA for ECS28A, with this sleep, CTS
> > > * android.hardware.camera2.cts.CameraDeviceTest#testCameraDeviceAbort
> > > * PASS, no impact on other platforms
> > > - */
> > > + */
> > > if (IS_BYT && enable)
> > > msleep(10);
> > >
> > > @@ -727,7 +727,7 @@ static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable)
> > > iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, MRFLD_ISPSSPM0,
> > > val, MRFLD_ISPSSPM0_ISPSSC_MASK);
> > >
> > > - /*WA:Enable DVFS*/
> > > + /* WA:Enable DVFS */
> > > if (IS_CHT && !enable)
> > > punit_ddr_dvfs_enable(true);
> > >
> > > --
> > > 2.33.1
> > >
> > >
> >
>