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

[Manasi Navare]

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 at intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
Cc: Animesh Manna <animesh.manna at intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Sean Paul <sean at poorly.run>
Cc: Drew Davenport <ddavenport at chromium.org>
Signed-off-by: Manasi Navare <navaremanasi at 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)
 #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
-- 
2.43.0.594.gd9cf4e227d-goog