Re: [PATCH v4 16/39] drm/msm/dp: use stream_id to change offsets in dp_catalog

From: Dmitry Baryshkov

Date: Mon May 25 2026 - 04:23:12 EST


On Mon, May 25, 2026 at 04:06:08PM +0800, Yongxing Mou wrote:
>
>
> On 4/12/2026 2:12 AM, Dmitry Baryshkov wrote:
> > On Fri, Apr 10, 2026 at 05:33:51PM +0800, Yongxing Mou wrote:
> > > From: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> > >
> > > Use the dp_panel's stream_id to adjust the offsets for stream 1 which will
> > > be used for MST in the dp_catalog.
> >
> > Please start by describing the problem.
> >
> Got it, thanks.
> > > Stream 1 share the same link clk with
> > > stream 0 with different reg offset. Also add additional register defines
> > > for stream 1.
> > >
> > > Streams 2 and 3 are not covered here, as they use separate link clocks and
> > > require separate handling.
> > >
> > > Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> > > Signed-off-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx>
> > > ---
> > > drivers/gpu/drm/msm/dp/dp_ctrl.c | 24 ++++++++++---
> > > drivers/gpu/drm/msm/dp/dp_panel.c | 72 +++++++++++++++++++++++++++------------
> > > drivers/gpu/drm/msm/dp/dp_reg.h | 11 ++++++
> > > 3 files changed, 81 insertions(+), 26 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/msm/dp/dp_reg.h b/drivers/gpu/drm/msm/dp/dp_reg.h
> > > index 3689642b7fc0..295c1161e6b7 100644
> > > --- a/drivers/gpu/drm/msm/dp/dp_reg.h
> > > +++ b/drivers/gpu/drm/msm/dp/dp_reg.h
> > > @@ -332,6 +332,17 @@
> > > #define DP_TPG_VIDEO_CONFIG_BPP_8BIT (0x00000001)
> > > #define DP_TPG_VIDEO_CONFIG_RGB (0x00000004)
> > > +/* DP MST registers */
> >
> > Which register spaces are they from?
> >
> Here also from DPTX_*, what about this? /* DP_TX MST registers */

Why? don't separate them from the registers from the same space. Also,
please, name them uniformly. Why some of those are REG_DP1 and others
are MMSS_DP1?

> > > +#define REG_DP1_CONFIGURATION_CTRL (0x00000400)
> > > +#define REG_DP1_SOFTWARE_MVID (0x00000414)
> > > +#define REG_DP1_SOFTWARE_NVID (0x00000418)
> > > +#define REG_DP1_TOTAL_HOR_VER (0x0000041C)
> > > +#define REG_DP1_MISC1_MISC0 (0x0000042C)
> > > +#define MMSS_DP1_GENERIC0_0 (0x00000490)
> > > +#define MMSS_DP1_SDP_CFG (0x000004E0)
> > > +#define MMSS_DP1_SDP_CFG2 (0x000004E4)
> > > +#define MMSS_DP1_SDP_CFG3 (0x000004E8)
> > > +
> > > #define MMSS_DP_ASYNC_FIFO_CONFIG (0x00000088)
> > > #define REG_DP_PHY_AUX_INTERRUPT_CLEAR (0x0000004C)
> > >

--
With best wishes
Dmitry