[Intel-gfx] [PATCH 15/23] drm/i915/dsc: Define & Compute VESA DSC params

Manasi Navare manasi.d.navare at intel.com
Tue Jul 31 02:12:55 UTC 2018


From: Gaurav K Singh <gaurav.k.singh at 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.

v5 (From Manasi):
* Add logic to limit the max line buf depth for DSC 1.1 to 13
as per DSC 1.1 spec

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 at linux.intel.com>
Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
Cc: Gaurav K Singh <gaurav.k.singh at intel.com>
Signed-off-by: Gaurav K Singh <gaurav.k.singh at intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare at 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 | 459 ++++++++++++++++++++++++++++++++++++++
 include/drm/drm_dp_helper.h       |   3 +
 include/drm/drm_dsc.h             |   2 +-
 6 files changed, 476 insertions(+), 2 deletions(-)
 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 5794f10..deaf2d4 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -153,7 +153,8 @@ 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 fb179f1..d7fc50f 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2042,6 +2042,13 @@ 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 ab567c3..01ab23d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1749,6 +1749,10 @@ 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 0000000..33b5300
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_vdsc.c
@@ -0,0 +1,459 @@
+/*
+ * Copyright © 2018 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Author: Gaurav K Singh <gaurav.k.singh at intel.com>
+ *         Manasi Navare <manasi.d.navare at 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 (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] =
+			rc_params[row_index][column_index].rc_range_params[i];
+
+	/*
+	 * 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;
+
+	/* 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 0cf2407..f178933 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -186,6 +186,9 @@
 
 #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)
 
diff --git a/include/drm/drm_dsc.h b/include/drm/drm_dsc.h
index 4cfcd03..796c798 100644
--- a/include/drm/drm_dsc.h
+++ b/include/drm/drm_dsc.h
@@ -67,7 +67,7 @@ struct dsc_rc_range_parameters {
 	/* Max Quantization Parameters allowed for this range */
 	u8 range_max_qp;
 	/* Bits/group offset to apply to target for this group */
-	u8 range_bpg_offset;
+	s8 range_bpg_offset;
 };
 
 struct drm_dsc_config {
-- 
2.7.4



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