[PATCH v6 16/28] drm/i915/dsc: Define & Compute VESA DSC params

[Manasi Navare <manasi.d.navare@intel.com>]

From: Gaurav K Singh <gaurav.k.singh@intel.com>

This patches does the following:

1. This patch defines all the DSC parameters as per the VESA
DSC specification. These are stored in the encoder and used
to compute the PPS parameters to be sent to the Sink.
2. Compute all the DSC parameters which are derived from DSC
state of intel_crtc_state.
3. Compute all parameters that are VESA DSC specific

This computation happens in the atomic check phase during
compute_config() to validate if display stream compression
can be enabled for the requested mode.

v7: (From Manasi)
* Dont use signed int for rc_range_params (Manasi)
* Mask the range_bpg_offset to use only 6 bits
* Add SPDX identifier (Chris Wilson)
v6 (From Manasi):
* Add a check for line_buf_depth return value (Anusha)
* Remove DRM DSC constants to different patch (Manasi)
v5 (From Manasi):
* Add logic to limit the max line buf depth for DSC 1.1 to 13
as per DSC 1.1 spec
* Fix dim checkpatch warnings/checks

v4 (From Gaurav):
* Rebase on latest drm tip
* rename variable name(Manasi)
* Populate linebuf_depth variable(Manasi)

v3 (From Gaurav):
* Rebase my previous patches on top of Manasi's latest patch
series
* Using >>n rather than /2^n (Manasi)
* Change the commit message to explain what the patch is doing(Gaurav)

Fixed review comments from Ville:
* Don't use macro TWOS_COMPLEMENT
* Mention in comment about the source of RC params
* Return directly from case statements
* Using single asssignment for assigning rc_range_params
* Using <<n rather than *2^n and removing the comments
about the fixed point numbers

v2 (From Manasi):
* Update logic for minor version to consider the dpcd value
and what supported by the HW platform
* Use DRM DSC config struct instead of intel_dp struct
* Move the DSC constants to DRM DSC header file
* Use u16, u8 where bigger data types not needed
* * Compute the DSC parameters as part of DSC compute config
since the computation can fail (Manasi)

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Gaurav K Singh <gaurav.k.singh@intel.com>
Signed-off-by: Gaurav K Singh <gaurav.k.singh@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Co-developed-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
---
 drivers/gpu/drm/i915/Makefile     |   3 +-
 drivers/gpu/drm/i915/intel_dp.c   |   7 +
 drivers/gpu/drm/i915/intel_drv.h  |   4 +
 drivers/gpu/drm/i915/intel_vdsc.c | 455 ++++++++++++++++++++++++++++++
 include/drm/drm_dp_helper.h       |   3 +
 5 files changed, 471 insertions(+), 1 deletion(-)
 create mode 100644 drivers/gpu/drm/i915/intel_vdsc.c

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 28c7d7884e88..a51a9ae0f496 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -156,7 +156,8 @@ i915-y += dvo_ch7017.o \
 	  intel_sdvo.o \
 	  intel_tv.o \
 	  vlv_dsi.o \
-	  vlv_dsi_pll.o
+	  vlv_dsi_pll.o \
+	  intel_vdsc.o
 
 # Post-mortem debug and GPU hang state capture
 i915-$(CONFIG_DRM_I915_CAPTURE_ERROR) += i915_gpu_error.o
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index a88f9371dd32..35162c3bc811 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2103,6 +2103,13 @@ static bool intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
 			return false;
 		}
 	}
+	if (intel_dp_compute_dsc_params(intel_dp, pipe_config) < 0) {
+		DRM_ERROR("Cannot compute valid DSC parameters for Input Bpp = %d"
+			  "Compressed BPP = %d\n",
+			  pipe_config->pipe_bpp,
+			  pipe_config->dsc_params.compressed_bpp);
+		return false;
+	}
 	pipe_config->dsc_params.compression_enable = true;
 	DRM_DEBUG_KMS("DP DSC computed with Input Bpp = %d "
 		      "Compressed Bpp = %d Slice Count = %d\n",
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 27d47950f438..c4be4ba7adac 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1844,6 +1844,10 @@ uint16_t intel_dp_dsc_get_output_bpp(int link_clock, uint8_t lane_count,
 uint8_t intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp, int mode_clock,
 				     int mode_hdisplay);
 
+/* intel_vdsc.c */
+int intel_dp_compute_dsc_params(struct intel_dp *intel_dp,
+				struct intel_crtc_state *pipe_config);
+
 static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
 {
 	return ~((1 << lane_count) - 1) & 0xf;
diff --git a/drivers/gpu/drm/i915/intel_vdsc.c b/drivers/gpu/drm/i915/intel_vdsc.c
new file mode 100644
index 000000000000..351ea7d71c21
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_vdsc.c
@@ -0,0 +1,455 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2018 Intel Corporation
+ *
+ * Author: Gaurav K Singh <gaurav.k.singh@intel.com>
+ *         Manasi Navare <manasi.d.navare@intel.com>
+ */
+
+#include <drm/drmP.h>
+#include <drm/i915_drm.h>
+#include "i915_drv.h"
+#include "intel_drv.h"
+
+enum ROW_INDEX_BPP {
+	ROW_INDEX_6BPP = 0,
+	ROW_INDEX_8BPP,
+	ROW_INDEX_10BPP,
+	ROW_INDEX_12BPP,
+	ROW_INDEX_15BPP,
+	MAX_ROW_INDEX
+};
+
+enum COLUMN_INDEX_BPC {
+	COLUMN_INDEX_8BPC = 0,
+	COLUMN_INDEX_10BPC,
+	COLUMN_INDEX_12BPC,
+	COLUMN_INDEX_14BPC,
+	COLUMN_INDEX_16BPC,
+	MAX_COLUMN_INDEX
+};
+
+#define DSC_SUPPORTED_VERSION_MIN		1
+
+/* From DSC_v1.11 spec, rc_parameter_Set syntax element typically constant */
+static u16 rc_buf_thresh[] = {
+	896, 1792, 2688, 3584, 4480, 5376, 6272, 6720, 7168, 7616,
+	7744, 7872, 8000, 8064
+};
+
+struct rc_parameters {
+	u16 initial_xmit_delay;
+	u8 first_line_bpg_offset;
+	u16 initial_offset;
+	u8 flatness_min_qp;
+	u8 flatness_max_qp;
+	u8 rc_quant_incr_limit0;
+	u8 rc_quant_incr_limit1;
+	struct dsc_rc_range_parameters rc_range_params[DSC_NUM_BUF_RANGES];
+};
+
+/*
+ * Selected Rate Control Related Parameter Recommended Values
+ * from DSC_v1.11 spec & C Model release: DSC_model_20161212
+ */
+static struct rc_parameters rc_params[][MAX_COLUMN_INDEX] = {
+{
+	/* 6BPP/8BPC */
+	{ 768, 15, 6144, 3, 13, 11, 11, {
+		{ 0, 4, 0 }, { 1, 6, -2 }, { 3, 8, -2 }, { 4, 8, -4 },
+		{ 5, 9, -6 }, { 5, 9, -6 }, { 6, 9, -6 }, { 6, 10, -8 },
+		{ 7, 11, -8 }, { 8, 12, -10 }, { 9, 12, -10 }, { 10, 12, -12 },
+		{ 10, 12, -12 }, { 11, 12, -12 }, { 13, 14, -12 }
+		}
+	},
+	/* 6BPP/10BPC */
+	{ 768, 15, 6144, 7, 17, 15, 15, {
+		{ 0, 8, 0 }, { 3, 10, -2 }, { 7, 12, -2 }, { 8, 12, -4 },
+		{ 9, 13, -6 }, { 9, 13, -6 }, { 10, 13, -6 }, { 10, 14, -8 },
+		{ 11, 15, -8 }, { 12, 16, -10 }, { 13, 16, -10 },
+		{ 14, 16, -12 }, { 14, 16, -12 }, { 15, 16, -12 },
+		{ 17, 18, -12 }
+		}
+	},
+	/* 6BPP/12BPC */
+	{ 768, 15, 6144, 11, 21, 19, 19, {
+		{ 0, 12, 0 }, { 5, 14, -2 }, { 11, 16, -2 }, { 12, 16, -4 },
+		{ 13, 17, -6 }, { 13, 17, -6 }, { 14, 17, -6 }, { 14, 18, -8 },
+		{ 15, 19, -8 }, { 16, 20, -10 }, { 17, 20, -10 },
+		{ 18, 20, -12 }, { 18, 20, -12 }, { 19, 20, -12 },
+		{ 21, 22, -12 }
+		}
+	},
+	/* 6BPP/14BPC */
+	{ 768, 15, 6144, 15, 25, 23, 27, {
+		{ 0, 16, 0 }, { 7, 18, -2 }, { 15, 20, -2 }, { 16, 20, -4 },
+		{ 17, 21, -6 }, { 17, 21, -6 }, { 18, 21, -6 }, { 18, 22, -8 },
+		{ 19, 23, -8 }, { 20, 24, -10 }, { 21, 24, -10 },
+		{ 22, 24, -12 }, { 22, 24, -12 }, { 23, 24, -12 },
+		{ 25, 26, -12 }
+		}
+	},
+	/* 6BPP/16BPC */
+	{ 768, 15, 6144, 19, 29, 27, 27, {
+		{ 0, 20, 0 }, { 9, 22, -2 }, { 19, 24, -2 }, { 20, 24, -4 },
+		{ 21, 25, -6 }, { 21, 25, -6 }, { 22, 25, -6 }, { 22, 26, -8 },
+		{ 23, 27, -8 }, { 24, 28, -10 }, { 25, 28, -10 },
+		{ 26, 28, -12 }, { 26, 28, -12 }, { 27, 28, -12 },
+		{ 29, 30, -12 }
+		}
+	},
+},
+{
+	/* 8BPP/8BPC */
+	{ 512, 12, 6144, 3, 12, 11, 11, {
+		{ 0, 4, 2 }, { 0, 4, 0 }, { 1, 5, 0 }, { 1, 6, -2 },
+		{ 3, 7, -4 }, { 3, 7, -6 }, { 3, 7, -8 }, { 3, 8, -8 },
+		{ 3, 9, -8 }, { 3, 10, -10 }, { 5, 11, -10 }, { 5, 12, -12 },
+		{ 5, 13, -12 }, { 7, 13, -12 }, { 13, 15, -12 }
+		}
+	},
+	/* 8BPP/10BPC */
+	{ 512, 12, 6144, 7, 16, 15, 15, {
+		{ 0, 4, 2 }, { 4, 8, 0 }, { 5, 9, 0 }, { 5, 10, -2 },
+		{ 7, 11, -4 }, { 7, 11, -6 }, { 7, 11, -8 }, { 7, 12, -8 },
+		{ 7, 13, -8 }, { 7, 14, -10 }, { 9, 15, -10 }, { 9, 16, -12 },
+		{ 9, 17, -12 }, { 11, 17, -12 }, { 17, 19, -12 }
+		}
+	},
+	/* 8BPP/12BPC */
+	{ 512, 12, 6144, 11, 20, 19, 19, {
+		{ 0, 12, 2 }, { 4, 12, 0 }, { 9, 13, 0 }, { 9, 14, -2 },
+		{ 11, 15, -4 }, { 11, 15, -6 }, { 11, 15, -8 }, { 11, 16, -8 },
+		{ 11, 17, -8 }, { 11, 18, -10 }, { 13, 19, -10 },
+		{ 13, 20, -12 }, { 13, 21, -12 }, { 15, 21, -12 },
+		{ 21, 23, -12 }
+		}
+	},
+	/* 8BPP/14BPC */
+	{ 512, 12, 6144, 15, 24, 23, 23, {
+		{ 0, 12, 0 }, { 5, 13, 0 }, { 11, 15, 0 }, { 12, 17, -2 },
+		{ 15, 19, -4 }, { 15, 19, -6 }, { 15, 19, -8 }, { 15, 20, -8 },
+		{ 15, 21, -8 }, { 15, 22, -10 }, { 17, 22, -10 },
+		{ 17, 23, -12 }, { 17, 23, -12 }, { 21, 24, -12 },
+		{ 24, 25, -12 }
+		}
+	},
+	/* 8BPP/16BPC */
+	{ 512, 12, 6144, 19, 28, 27, 27, {
+		{ 0, 12, 2 }, { 6, 14, 0 }, { 13, 17, 0 }, { 15, 20, -2 },
+		{ 19, 23, -4 }, { 19, 23, -6 }, { 19, 23, -8 }, { 19, 24, -8 },
+		{ 19, 25, -8 }, { 19, 26, -10 }, { 21, 26, -10 },
+		{ 21, 27, -12 }, { 21, 27, -12 }, { 25, 28, -12 },
+		{ 28, 29, -12 }
+		}
+	},
+},
+{
+	/* 10BPP/8BPC */
+	{ 410, 15, 5632, 3, 12, 11, 11, {
+		{ 0, 3, 2 }, { 0, 4, 0 }, { 1, 5, 0 }, { 2, 6, -2 },
+		{ 3, 7, -4 }, { 3, 7, -6 }, { 3, 7, -8 }, { 3, 8, -8 },
+		{ 3, 9, -8 }, { 3, 9, -10 }, { 5, 10, -10 }, { 5, 10, -10 },
+		{ 5, 11, -12 }, { 7, 11, -12 }, { 11, 12, -12 }
+		}
+	},
+	/* 10BPP/10BPC */
+	{ 410, 15, 5632, 7, 16, 15, 15, {
+		{ 0, 7, 2 }, { 4, 8, 0 }, { 5, 9, 0 }, { 6, 10, -2 },
+		{ 7, 11, -4 }, { 7, 11, -6 }, { 7, 11, -8 }, { 7, 12, -8 },
+		{ 7, 13, -8 }, { 7, 13, -10 }, { 9, 14, -10 }, { 9, 14, -10 },
+		{ 9, 15, -12 }, { 11, 15, -12 }, { 15, 16, -12 }
+		}
+	},
+	/* 10BPP/12BPC */
+	{ 410, 15, 5632, 11, 20, 19, 19, {
+		{ 0, 11, 2 }, { 4, 12, 0 }, { 9, 13, 0 }, { 10, 14, -2 },
+		{ 11, 15, -4 }, { 11, 15, -6 }, { 11, 15, -8 }, { 11, 16, -8 },
+		{ 11, 17, -8 }, { 11, 17, -10 }, { 13, 18, -10 },
+		{ 13, 18, -10 }, { 13, 19, -12 }, { 15, 19, -12 },
+		{ 19, 20, -12 }
+		}
+	},
+	/* 10BPP/14BPC */
+	{ 410, 15, 5632, 15, 24, 23, 23, {
+		{ 0, 11, 2 }, { 5, 13, 0 }, { 11, 15, 0 }, { 13, 18, -2 },
+		{ 15, 19, -4 }, { 15, 19, -6 }, { 15, 19, -8 }, { 15, 20, -8 },
+		{ 15, 21, -8 }, { 15, 21, -10 }, { 17, 22, -10 },
+		{ 17, 22, -10 }, { 17, 23, -12 }, { 19, 23, -12 },
+		{ 23, 24, -12 }
+		}
+	},
+	/* 10BPP/16BPC */
+	{ 410, 15, 5632, 19, 28, 27, 27, {
+		{ 0, 11, 2 }, { 6, 14, 0 }, { 13, 17, 0 }, { 16, 20, -2 },
+		{ 19, 23, -4 }, { 19, 23, -6 }, { 19, 23, -8 }, { 19, 24, -8 },
+		{ 19, 25, -8 }, { 19, 25, -10 }, { 21, 26, -10 },
+		{ 21, 26, -10 }, { 21, 27, -12 }, { 23, 27, -12 },
+		{ 27, 28, -12 }
+		}
+	},
+},
+{
+	/* 12BPP/8BPC */
+	{ 341, 15, 2048, 3, 12, 11, 11, {
+		{ 0, 2, 2 }, { 0, 4, 0 }, { 1, 5, 0 }, { 1, 6, -2 },
+		{ 3, 7, -4 }, { 3, 7, -6 }, { 3, 7, -8 }, { 3, 8, -8 },
+		{ 3, 9, -8 }, { 3, 10, -10 }, { 5, 11, -10 },
+		{ 5, 12, -12 }, { 5, 13, -12 }, { 7, 13, -12 }, { 13, 15, -12 }
+		}
+	},
+	/* 12BPP/10BPC */
+	{ 341, 15, 2048, 7, 16, 15, 15, {
+		{ 0, 2, 2 }, { 2, 5, 0 }, { 3, 7, 0 }, { 4, 8, -2 },
+		{ 6, 9, -4 }, { 7, 10, -6 }, { 7, 11, -8 }, { 7, 12, -8 },
+		{ 7, 13, -8 }, { 7, 14, -10 }, { 9, 15, -10 }, { 9, 16, -12 },
+		{ 9, 17, -12 }, { 11, 17, -12 }, { 17, 19, -12 }
+		}
+	},
+	/* 12BPP/12BPC */
+	{ 341, 15, 2048, 11, 20, 19, 19, {
+		{ 0, 6, 2 }, { 4, 9, 0 }, { 7, 11, 0 }, { 8, 12, -2 },
+		{ 10, 13, -4 }, { 11, 14, -6 }, { 11, 15, -8 }, { 11, 16, -8 },
+		{ 11, 17, -8 }, { 11, 18, -10 }, { 13, 19, -10 },
+		{ 13, 20, -12 }, { 13, 21, -12 }, { 15, 21, -12 },
+		{ 21, 23, -12 }
+		}
+	},
+	/* 12BPP/14BPC */
+	{ 341, 15, 2048, 15, 24, 23, 23, {
+		{ 0, 6, 2 }, { 7, 10, 0 }, { 9, 13, 0 }, { 11, 16, -2 },
+		{ 14, 17, -4 }, { 15, 18, -6 }, { 15, 19, -8 }, { 15, 20, -8 },
+		{ 15, 20, -8 }, { 15, 21, -10 }, { 17, 21, -10 },
+		{ 17, 21, -12 }, { 17, 21, -12 }, { 19, 22, -12 },
+		{ 22, 23, -12 }
+		}
+	},
+	/* 12BPP/16BPC */
+	{ 341, 15, 2048, 19, 28, 27, 27, {
+		{ 0, 6, 2 }, { 6, 11, 0 }, { 11, 15, 0 }, { 14, 18, -2 },
+		{ 18, 21, -4 }, { 19, 22, -6 }, { 19, 23, -8 }, { 19, 24, -8 },
+		{ 19, 24, -8 }, { 19, 25, -10 }, { 21, 25, -10 },
+		{ 21, 25, -12 }, { 21, 25, -12 }, { 23, 26, -12 },
+		{ 26, 27, -12 }
+		}
+	},
+},
+{
+	/* 15BPP/8BPC */
+	{ 273, 15, 2048, 3, 12, 11, 11, {
+		{ 0, 0, 10 }, { 0, 1, 8 }, { 0, 1, 6 }, { 0, 2, 4 },
+		{ 1, 2, 2 }, { 1, 3, 0 }, { 1, 3, -2 }, { 2, 4, -4 },
+		{ 2, 5, -6 }, { 3, 5, -8 }, { 4, 6, -10 }, { 4, 7, -10 },
+		{ 5, 7, -12 }, { 7, 8, -12 }, { 8, 9, -12 }
+		}
+	},
+	/* 15BPP/10BPC */
+	{ 273, 15, 2048, 7, 16, 15, 15, {
+		{ 0, 2, 10 }, { 2, 5, 8 }, { 3, 5, 6 }, { 4, 6, 4 },
+		{ 5, 6, 2 }, { 5, 7, 0 }, { 5, 7, -2 }, { 6, 8, -4 },
+		{ 6, 9, -6 }, { 7, 9, -8 }, { 8, 10, -10 }, { 8, 11, -10 },
+		{ 9, 11, -12 }, { 11, 12, -12 }, { 12, 13, -12 }
+		}
+	},
+	/* 15BPP/12BPC */
+	{ 273, 15, 2048, 11, 20, 19, 19, {
+		{ 0, 4, 10 }, { 2, 7, 8 }, { 4, 9, 6 }, { 6, 11, 4 },
+		{ 9, 11, 2 }, { 9, 11, 0 }, { 9, 12, -2 }, { 10, 12, -4 },
+		{ 11, 13, -6 }, { 11, 13, -8 }, { 12, 14, -10 },
+		{ 13, 15, -10 }, { 13, 15, -12 }, { 15, 16, -12 },
+		{ 16, 17, -12 }
+		}
+	},
+	/* 15BPP/14BPC */
+	{ 273, 15, 2048, 15, 24, 23, 23, {
+		{ 0, 4, 10 }, { 3, 8, 8 }, { 6, 11, 6 }, { 9, 14, 4 },
+		{ 13, 15, 2 }, { 13, 15, 0 }, { 13, 16, -2 }, { 14, 16, -4 },
+		{ 15, 17, -6 }, { 15, 17, -8 }, { 16, 18, -10 },
+		{ 17, 19, -10 }, { 17, 19, -12 }, { 19, 20, -12 },
+		{ 20, 21, -12 }
+		}
+	},
+	/* 15BPP/16BPC */
+	{ 273, 15, 2048, 19, 28, 27, 27, {
+		{ 0, 4, 10 }, { 4, 9, 8 }, { 8, 13, 6 }, { 12, 17, 4 },
+		{ 17, 19, 2 }, { 17, 20, 0 }, { 17, 20, -2 }, { 18, 20, -4 },
+		{ 19, 21, -6 }, { 19, 21, -8 }, { 20, 22, -10 },
+		{ 21, 23, -10 }, { 21, 23, -12 }, { 23, 24, -12 },
+		{ 24, 25, -12 }
+		}
+	}
+}
+};
+
+static int get_row_index_for_rc_params(u16 compressed_bpp)
+{
+	switch (compressed_bpp) {
+	case 6:
+		return ROW_INDEX_6BPP;
+	case 8:
+		return ROW_INDEX_8BPP;
+	case 10:
+		return ROW_INDEX_10BPP;
+	case 12:
+		return ROW_INDEX_12BPP;
+	case 15:
+		return ROW_INDEX_15BPP;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int get_column_index_for_rc_params(u8 bits_per_component)
+{
+	switch (bits_per_component) {
+	case 8:
+		return COLUMN_INDEX_8BPC;
+	case 10:
+		return COLUMN_INDEX_10BPC;
+	case 12:
+		return COLUMN_INDEX_12BPC;
+	case 14:
+		return COLUMN_INDEX_14BPC;
+	case 16:
+		return COLUMN_INDEX_16BPC;
+	default:
+		return -EINVAL;
+	}
+}
+
+int intel_dp_compute_dsc_params(struct intel_dp *intel_dp,
+				struct intel_crtc_state *pipe_config)
+{
+	struct drm_dsc_config *vdsc_cfg = &pipe_config->dp_dsc_cfg;
+	u16 compressed_bpp = pipe_config->dsc_params.compressed_bpp;
+	u8 i = 0;
+	u8 row_index = 0;
+	u8 column_index = 0;
+	u8 line_buf_depth = 0;
+
+	vdsc_cfg->pic_width = pipe_config->base.adjusted_mode.crtc_hdisplay;
+	vdsc_cfg->pic_height = pipe_config->base.adjusted_mode.crtc_vdisplay;
+	vdsc_cfg->slice_width = DIV_ROUND_UP(vdsc_cfg->pic_width,
+					     pipe_config->dsc_params.slice_count);
+	/*
+	 * Slice Height of 8 works for all currently available panels. So start
+	 * with that if pic_height is an integral multiple of 8.
+	 * Eventually add logic to try multiple slice heights.
+	 */
+	if (vdsc_cfg->pic_height % 8 == 0)
+		vdsc_cfg->slice_height = 8;
+	else if (vdsc_cfg->pic_height % 4 == 0)
+		vdsc_cfg->slice_height = 4;
+	else
+		vdsc_cfg->slice_height = 2;
+
+	/* Values filled from DSC Sink DPCD */
+	vdsc_cfg->dsc_version_major =
+		(intel_dp->dsc_dpcd[DP_DSC_REV - DP_DSC_SUPPORT] &
+		 DP_DSC_MAJOR_MASK) >> DP_DSC_MAJOR_SHIFT;
+	vdsc_cfg->dsc_version_minor =
+		min(DSC_SUPPORTED_VERSION_MIN,
+		    (intel_dp->dsc_dpcd[DP_DSC_REV - DP_DSC_SUPPORT] &
+		     DP_DSC_MINOR_MASK) >> DP_DSC_MINOR_SHIFT);
+
+	vdsc_cfg->convert_rgb = intel_dp->dsc_dpcd[DP_DSC_DEC_COLOR_FORMAT_CAP - DP_DSC_SUPPORT] &
+		DP_DSC_RGB;
+
+	line_buf_depth = drm_dp_dsc_sink_line_buf_depth(intel_dp->dsc_dpcd);
+	if (!line_buf_depth) {
+		DRM_DEBUG_KMS("DSC Sink Line Buffer Depth invalid\n");
+		return -EINVAL;
+	}
+	if (vdsc_cfg->dsc_version_minor == 2)
+		vdsc_cfg->line_buf_depth = (line_buf_depth == DSC_1_2_MAX_LINEBUF_DEPTH_BITS) ?
+			DSC_1_2_MAX_LINEBUF_DEPTH_VAL : line_buf_depth;
+	else
+		vdsc_cfg->line_buf_depth = (line_buf_depth > DSC_1_1_MAX_LINEBUF_DEPTH_BITS) ?
+			DSC_1_1_MAX_LINEBUF_DEPTH_BITS : line_buf_depth;
+
+	/* Gen 11 does not support YCbCr */
+	vdsc_cfg->enable422 = false;
+	/* Gen 11 does not support VBR */
+	vdsc_cfg->vbr_enable = false;
+	vdsc_cfg->block_pred_enable =
+			intel_dp->dsc_dpcd[DP_DSC_BLK_PREDICTION_SUPPORT - DP_DSC_SUPPORT] &
+		DP_DSC_BLK_PREDICTION_IS_SUPPORTED;
+
+	/* Gen 11 only supports integral values of bpp */
+	vdsc_cfg->bits_per_pixel = compressed_bpp << 4;
+	vdsc_cfg->bits_per_component = pipe_config->pipe_bpp / 3;
+
+	for (i = 0; i < DSC_NUM_BUF_RANGES - 1; i++) {
+		/*
+		 * six 0s are appended to the lsb of each threshold value
+		 * internally in h/w.
+		 * Only 8 bits are allowed for programming RcBufThreshold
+		 */
+		vdsc_cfg->rc_buf_thresh[i] = rc_buf_thresh[i] >> 6;
+	}
+
+	/*
+	 * For 6bpp, RC Buffer threshold 12 and 13 need a different value
+	 * as per C Model
+	 */
+	if (compressed_bpp == 6) {
+		vdsc_cfg->rc_buf_thresh[12] = 0x7C;
+		vdsc_cfg->rc_buf_thresh[13] = 0x7D;
+	}
+
+	row_index = get_row_index_for_rc_params(compressed_bpp);
+	column_index =
+		get_column_index_for_rc_params(vdsc_cfg->bits_per_component);
+
+	if (row_index < 0 || column_index < 0)
+		return -EINVAL;
+
+	vdsc_cfg->first_line_bpg_offset =
+		rc_params[row_index][column_index].first_line_bpg_offset;
+	vdsc_cfg->initial_xmit_delay =
+		rc_params[row_index][column_index].initial_xmit_delay;
+	vdsc_cfg->initial_offset =
+		rc_params[row_index][column_index].initial_offset;
+	vdsc_cfg->flatness_min_qp =
+		rc_params[row_index][column_index].flatness_min_qp;
+	vdsc_cfg->flatness_max_qp =
+		rc_params[row_index][column_index].flatness_max_qp;
+	vdsc_cfg->rc_quant_incr_limit0 =
+		rc_params[row_index][column_index].rc_quant_incr_limit0;
+	vdsc_cfg->rc_quant_incr_limit1 =
+		rc_params[row_index][column_index].rc_quant_incr_limit1;
+
+	for (i = 0; i < DSC_NUM_BUF_RANGES; i++) {
+		vdsc_cfg->rc_range_params[i].range_min_qp =
+			rc_params[row_index][column_index].rc_range_params[i].range_min_qp;
+		vdsc_cfg->rc_range_params[i].range_max_qp =
+			rc_params[row_index][column_index].rc_range_params[i].range_max_qp;
+		/*
+		 * Range BPG Offset uses 2's complement and is only a 6 bits. So
+		 * mask it to get only 6 bits.
+		 */
+		vdsc_cfg->rc_range_params[i].range_bpg_offset =
+			rc_params[row_index][column_index].rc_range_params[i].range_bpg_offset &
+			DSC_RANGE_BPG_OFFSET_MASK;
+	}
+
+	/*
+	 * BitsPerComponent value determines mux_word_size:
+	 * When BitsPerComponent is 12bpc, muxWordSize will be equal to 64 bits
+	 * When BitsPerComponent is 8 or 10bpc, muxWordSize will be equal to
+	 * 48 bits
+	 */
+	if (vdsc_cfg->bits_per_component == 8 ||
+	    vdsc_cfg->bits_per_component == 10)
+		vdsc_cfg->mux_word_size = DSC_MUX_WORD_SIZE_8_10_BPC;
+	else if (vdsc_cfg->bits_per_component == 12)
+		vdsc_cfg->mux_word_size = DSC_MUX_WORD_SIZE_12_BPC;
+
+	/* RC_MODEL_SIZE is a constant across all configurations */
+	vdsc_cfg->rc_model_size = DSC_RC_MODEL_SIZE_CONST;
+	/* InitialScaleValue is a 6 bit value with 3 fractional bits (U3.3) */
+	vdsc_cfg->initial_scale_value = (vdsc_cfg->rc_model_size << 3) /
+		(vdsc_cfg->rc_model_size - vdsc_cfg->initial_offset);
+
+	return 0;
+}
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 730243dd41e2..2649529d0d8f 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -187,6 +187,9 @@
 
 #define DP_GUID				    0x030   /* 1.2 */
 
+#define DP_DSC_RC_PIXELS_PER_GROUP		3
+#define DP_DSC_SCALE_DECREMENT_INTERVAL_MAX	4095
+
 #define DP_DSC_SUPPORT                      0x060   /* DP 1.4 */
 # define DP_DSC_DECOMPRESSION_IS_SUPPORTED  (1 << 0)
 
-- 
2.18.0

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