drm/amd/display: support "dummy pstate"

[why]
Existing support in DC for pstate only accounts for a single latency.  This is sufficient when the
variance of latency is small, or that pstate support isn't necessary for correct ASIC functionality.

Newer ASICs violate both existing assumptions.  PState support is mandatory of correct ASIC
functionality, but not all latencies have to be supported.  Existing code supports a "full p state" which
allows memory clock to change, but is hard for DCN to support (as it requires very large buffers).
New code will now fall back to a "dummy p state" support when "full p state" cannot be support.
This easy p state support should always be allowed.

[how]
Define a new latency in socBB.  Add fallback logic to support it.  Note DML is also updated to ensure
that fallback will always work.

Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ *
+ * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef _DCN20V2_DISPLAY_MODE_VBA_H_
+#define _DCN20V2_DISPLAY_MODE_VBA_H_
+
+void dml20v2_recalculate(struct display_mode_lib *mode_lib);
+void dml20v2_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib);
+
+#endif

drivers/gpu/drm/amd/display/dc/dml/dcn20/display_rq_dlg_calc_20v2.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ *
+ * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DML20V2_DISPLAY_RQ_DLG_CALC_H__
+#define __DML20V2_DISPLAY_RQ_DLG_CALC_H__
+
+#include "../dml_common_defs.h"
+#include "../display_rq_dlg_helpers.h"
+
+struct display_mode_lib;
+
+
+// Function: dml_rq_dlg_get_rq_reg
+//  Main entry point for test to get the register values out of this DML class.
+//  This function calls <get_rq_param> and <extract_rq_regs> fucntions to calculate
+//  and then populate the rq_regs struct
+// Input:
+//  pipe_src_param - pipe source configuration (e.g. vp, pitch, etc.)
+// Output:
+//  rq_regs - struct that holds all the RQ registers field value.
+//            See also: <display_rq_regs_st>
+void dml20v2_rq_dlg_get_rq_reg(
+		struct display_mode_lib *mode_lib,
+		display_rq_regs_st *rq_regs,
+		const display_pipe_params_st pipe_param);
+
+
+// Function: dml_rq_dlg_get_dlg_reg
+//   Calculate and return DLG and TTU register struct given the system setting
+// Output:
+//  dlg_regs - output DLG register struct
+//  ttu_regs - output DLG TTU register struct
+// Input:
+//  e2e_pipe_param - "compacted" array of e2e pipe param struct
+//  num_pipes - num of active "pipe" or "route"
+//  pipe_idx - index that identifies the e2e_pipe_param that corresponding to this dlg
+//  cstate - 0: when calculate min_ttu_vblank it is assumed cstate is not required. 1: Normal mode, cstate is considered.
+//           Added for legacy or unrealistic timing tests.
+void dml20v2_rq_dlg_get_dlg_reg(
+		struct display_mode_lib *mode_lib,
+		display_dlg_regs_st *dlg_regs,
+		display_ttu_regs_st *ttu_regs,
+		display_e2e_pipe_params_st *e2e_pipe_param,
+		const unsigned int num_pipes,
+		const unsigned int pipe_idx,
+		const bool cstate_en,
+		const bool pstate_en,
+		const bool vm_en,
+		const bool ignore_viewport_pos,
+		const bool immediate_flip_support);
+
+#endif