diff mbox series

[v2] drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address

Message ID 20240202204752.1210687-1-navaremanasi@chromium.org (mailing list archive)
State New, archived
Headers show
Series [v2] drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address | expand

Commit Message

Manasi Navare Feb. 2, 2024, 8:47 p.m. UTC
Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines
a new macro to calculate the DSC PPS register addresses with PPS number as an
input. This macro correctly calculates the addresses till PPS 11 since the
addresses increment by 4. So in that case the following macro works correctly
to give correct register address:
_MMIO(_DSCA_PPS_0 + (pps) * 4)

However after PPS 11, the register address for PPS 12 increments by 12 because
of RC Buffer memory allocation in between. Because of this discontinuity
in the address space, the macro calculates wrong addresses for PPS 12 - 16
resulting into incorrect DSC PPS parameter value read/writes causing DSC
corruption.

This fixes it by correcting this macro to add the offset of 12 for
PPS >=12.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10172
Fixes: bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register")
Cc: Suraj Kandpal <suraj.kandpal@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Drew Davenport <ddavenport@chromium.org>
Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
---
 drivers/gpu/drm/i915/display/intel_vdsc_regs.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Jani Nikula Feb. 5, 2024, 12:02 p.m. UTC | #1
On Fri, 02 Feb 2024, Manasi Navare <navaremanasi@chromium.org> wrote:
> Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines
> a new macro to calculate the DSC PPS register addresses with PPS number as an
> input. This macro correctly calculates the addresses till PPS 11 since the
> addresses increment by 4. So in that case the following macro works correctly
> to give correct register address:
> _MMIO(_DSCA_PPS_0 + (pps) * 4)
>
> However after PPS 11, the register address for PPS 12 increments by 12 because
> of RC Buffer memory allocation in between. Because of this discontinuity
> in the address space, the macro calculates wrong addresses for PPS 12 - 16
> resulting into incorrect DSC PPS parameter value read/writes causing DSC
> corruption.
>
> This fixes it by correcting this macro to add the offset of 12 for
> PPS >=12.
>
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10172
> Fixes: bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register")
> Cc: Suraj Kandpal <suraj.kandpal@intel.com>
> Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> Cc: Animesh Manna <animesh.manna@intel.com>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Sean Paul <sean@poorly.run>
> Cc: Drew Davenport <ddavenport@chromium.org>
> Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
> ---
>  drivers/gpu/drm/i915/display/intel_vdsc_regs.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> index 64f440fdc22b..e676440af369 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> @@ -51,8 +51,8 @@
>  #define DSCC_PICTURE_PARAMETER_SET_0		_MMIO(0x6BA00)
>  #define _DSCA_PPS_0				0x6B200
>  #define _DSCC_PPS_0				0x6BA00
> -#define DSCA_PPS(pps)				_MMIO(_DSCA_PPS_0 + (pps) * 4)
> -#define DSCC_PPS(pps)				_MMIO(_DSCC_PPS_0 + (pps) * 4)
> +#define DSCA_PPS(pps)				_MMIO(_DSCA_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)
> +#define DSCC_PPS(pps)				_MMIO(_DSCC_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)

pps still needs to be wrapped in parens like I said, to avoid precedence
issues. Also, spaces are needed around ":". They were all there in what
I suggested to be used, and checkpatch also notices both.

BR,
Jani.

>  #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PB	0x78270
>  #define _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB	0x78370
>  #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PC	0x78470
Manasi Navare Feb. 5, 2024, 5:46 p.m. UTC | #2
Hi Jani,

Yea I think I made that change after checkpatch but didnt do commit
--amend, let me address that and send the patch for review.

Regards
Manasi

On Mon, Feb 5, 2024 at 4:03 AM Jani Nikula <jani.nikula@linux.intel.com> wrote:
>
> On Fri, 02 Feb 2024, Manasi Navare <navaremanasi@chromium.org> wrote:
> > Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines
> > a new macro to calculate the DSC PPS register addresses with PPS number as an
> > input. This macro correctly calculates the addresses till PPS 11 since the
> > addresses increment by 4. So in that case the following macro works correctly
> > to give correct register address:
> > _MMIO(_DSCA_PPS_0 + (pps) * 4)
> >
> > However after PPS 11, the register address for PPS 12 increments by 12 because
> > of RC Buffer memory allocation in between. Because of this discontinuity
> > in the address space, the macro calculates wrong addresses for PPS 12 - 16
> > resulting into incorrect DSC PPS parameter value read/writes causing DSC
> > corruption.
> >
> > This fixes it by correcting this macro to add the offset of 12 for
> > PPS >=12.
> >
> > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10172
> > Fixes: bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register")
> > Cc: Suraj Kandpal <suraj.kandpal@intel.com>
> > Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> > Cc: Animesh Manna <animesh.manna@intel.com>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Cc: Sean Paul <sean@poorly.run>
> > Cc: Drew Davenport <ddavenport@chromium.org>
> > Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
> > ---
> >  drivers/gpu/drm/i915/display/intel_vdsc_regs.h | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> > index 64f440fdc22b..e676440af369 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> > +++ b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> > @@ -51,8 +51,8 @@
> >  #define DSCC_PICTURE_PARAMETER_SET_0         _MMIO(0x6BA00)
> >  #define _DSCA_PPS_0                          0x6B200
> >  #define _DSCC_PPS_0                          0x6BA00
> > -#define DSCA_PPS(pps)                                _MMIO(_DSCA_PPS_0 + (pps) * 4)
> > -#define DSCC_PPS(pps)                                _MMIO(_DSCC_PPS_0 + (pps) * 4)
> > +#define DSCA_PPS(pps)                                _MMIO(_DSCA_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)
> > +#define DSCC_PPS(pps)                                _MMIO(_DSCC_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)
>
> pps still needs to be wrapped in parens like I said, to avoid precedence
> issues. Also, spaces are needed around ":". They were all there in what
> I suggested to be used, and checkpatch also notices both.
>
> BR,
> Jani.
>
> >  #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PB 0x78270
> >  #define _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB 0x78370
> >  #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PC 0x78470
>
> --
> Jani Nikula, Intel
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
index 64f440fdc22b..e676440af369 100644
--- a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
+++ b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
@@ -51,8 +51,8 @@ 
 #define DSCC_PICTURE_PARAMETER_SET_0		_MMIO(0x6BA00)
 #define _DSCA_PPS_0				0x6B200
 #define _DSCC_PPS_0				0x6BA00
-#define DSCA_PPS(pps)				_MMIO(_DSCA_PPS_0 + (pps) * 4)
-#define DSCC_PPS(pps)				_MMIO(_DSCC_PPS_0 + (pps) * 4)
+#define DSCA_PPS(pps)				_MMIO(_DSCA_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)
+#define DSCC_PPS(pps)				_MMIO(_DSCC_PPS_0 + ((pps < 12) ? (pps):(pps + 12)) * 4)
 #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PB	0x78270
 #define _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB	0x78370
 #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PC	0x78470