From 962ac2dce56bb3aad1f82a4bbe3ada57a020287c Mon Sep 17 00:00:00 2001
From: Manasi Navare <navaremanasi@chromium.org>
Date: Mon, 5 Feb 2024 20:46:19 +0000
Subject: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg
address
Git-commit: 962ac2dce56bb3aad1f82a4bbe3ada57a020287c
Alt-commit: 6074be620c31dc2ae11af96a1a5ea95580976fb5
Patch-mainline: v6.8-rc5
References: git-fixes CVE-2024-26721 bsc#1222365
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.
v3: Add correct paranthesis for pps argument (Jani Nikula)
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>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240205204619.1991673-1-navaremanasi@chromium.org
(cherry picked from commit 6074be620c31dc2ae11af96a1a5ea95580976fb5)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
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..8b21dc8e26d5 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