Re: [PATCH 1/1] media: nxp: imx8-isi-debug: Add missing registers to debugfs output

Laurent Pinchart
2023-12-07T10:14:31Z

Hi Alexander,

On Thu, Dec 07, 2023 at 08:52:46AM +0100, Alexander Stein wrote:
> Am Mittwoch, 6. Dezember 2023, 23:36:36 CET schrieb Laurent Pinchart:
> > On Wed, Dec 06, 2023 at 10:44:01AM +0100, Alexander Stein wrote:
> > > The extended address registers are missing in the debug output register
> > > list. Add them.
> > >
> > > Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> > > ---
> > >
> > > drivers/media/platform/nxp/imx8-isi/imx8-isi-debug.c | 7 +++++++
> > > 1 file changed, 7 insertions(+)
> > >
> > > diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-debug.c
> > > b/drivers/media/platform/nxp/imx8-isi/imx8-isi-debug.c index
> > > 6709ab7ea1f3..3ac5685d6cc1 100644
> > > --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-debug.c
> > > +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-debug.c
> > > @@ -66,6 +66,13 @@ static int mxc_isi_debug_dump_regs_show(struct seq_file *m, void *p)
> > > MXC_ISI_DEBUG_REG(CHNL_OUT_BUF2_ADDR_V),
> > > MXC_ISI_DEBUG_REG(CHNL_SCL_IMG_CFG),
> > > MXC_ISI_DEBUG_REG(CHNL_FLOW_CTRL),
> > >
> > > + MXC_ISI_DEBUG_REG(CHNL_Y_BUF1_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_U_BUF1_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_V_BUF1_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_Y_BUF2_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_U_BUF2_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_V_BUF2_XTND_ADDR),
> > > + MXC_ISI_DEBUG_REG(CHNL_IN_BUF_XTND_ADDR),
> >
> > Those registers only exist in the i.MX8MP. The i.MX8MN referenece manual
> > lists them as reserved and indicates they read as 0's, so it should be
> > safe. The i.MX93 reference manual, however, doesn't list those
> > registers at all, so accessing them may lead to issues.
> >
> > How what platform(s) have you tested this patch ?
>
> Ah, you are right. That's something I didn't take into account. Up until now I
> only tested this on i.MX8MP. I hope I can test this on i.MX8MN and i.MX93
> soon.
> Otherwise dumping these registers can depend on pdata->has_36bit_dma just to
> be safe.

That sounds like a good solution to me. Will you do so in a v2 ?

> > > };
> > >
> > > struct mxc_isi_pipe *pipe = m->private;

--
Regards,

Laurent Pinchart