drm/amd/display: fix up reference clock abstractions

[why]
"reference clock" is a very overloaded variable in DC and causes confusion
as there are multiple sources of reference clock, which may be different values
incorrect input values to DML will cause DCHUB to be programmed improperly
and lead to hard to debug underflow issues

[how]
instead of using ref clock everywhere, specify WHICH ref clock:
- xtalin
- dccg refclk
- dchub refclk

these are all distinct values which may not be equal

Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: David Francis <David.Francis@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/calcs/dcn_calcs.c

@@ -466,7 +466,7 @@ static void dcn_bw_calc_rq_dlg_ttu(
 	input.clks_cfg.dcfclk_mhz = v->dcfclk;
 	input.clks_cfg.dispclk_mhz = v->dispclk;
 	input.clks_cfg.dppclk_mhz = v->dppclk;
-	input.clks_cfg.refclk_mhz = dc->res_pool->ref_clock_inKhz / 1000.0;
+	input.clks_cfg.refclk_mhz = dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000.0;
 	input.clks_cfg.socclk_mhz = v->socclk;
 	input.clks_cfg.voltage = v->voltage_level;
 //	dc->dml.logger = pool->base.logger;

drivers/gpu/drm/amd/display/dc/core/dc_resource.c

@@ -31,6 +31,8 @@
 #include "opp.h"
 #include "timing_generator.h"
 #include "transform.h"
+#include "dccg.h"
+#include "dchubbub.h"
 #include "dpp.h"
 #include "core_types.h"
 #include "set_mode_types.h"
@@ -163,7 +165,28 @@ struct resource_pool *dc_create_resource_pool(
 
 		if (dc->ctx->dc_bios->funcs->get_firmware_info(
 				dc->ctx->dc_bios, &fw_info) == BP_RESULT_OK) {
-				res_pool->ref_clock_inKhz = fw_info.pll_info.crystal_frequency;
+				res_pool->ref_clocks.xtalin_clock_inKhz = fw_info.pll_info.crystal_frequency;
+
+				if (IS_FPGA_MAXIMUS_DC(dc->ctx->dce_environment)) {
+					// On FPGA these dividers are currently not configured by GDB
+					res_pool->ref_clocks.dccg_ref_clock_inKhz = res_pool->ref_clocks.xtalin_clock_inKhz;
+					res_pool->ref_clocks.dchub_ref_clock_inKhz = res_pool->ref_clocks.xtalin_clock_inKhz;
+				} else if (res_pool->dccg && res_pool->hubbub) {
+					// If DCCG reference frequency cannot be determined (usually means not set to xtalin) then this is a critical error
+					// as this value must be known for DCHUB programming
+					(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
+							fw_info.pll_info.crystal_frequency,
+							&res_pool->ref_clocks.dccg_ref_clock_inKhz);
+
+					// Similarly, if DCHUB reference frequency cannot be determined, then it is also a critical error
+					(res_pool->hubbub->funcs->get_dchub_ref_freq)(res_pool->hubbub,
+							res_pool->ref_clocks.dccg_ref_clock_inKhz,
+							&res_pool->ref_clocks.dchub_ref_clock_inKhz);
+				} else {
+					// Not all ASICs have DCCG sw component
+					res_pool->ref_clocks.dccg_ref_clock_inKhz = res_pool->ref_clocks.xtalin_clock_inKhz;
+					res_pool->ref_clocks.dchub_ref_clock_inKhz = res_pool->ref_clocks.xtalin_clock_inKhz;
+				}
 			} else
 				ASSERT_CRITICAL(false);
 	}

drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c

@@ -2635,7 +2635,7 @@ void dce110_set_cursor_position(struct pipe_ctx *pipe_ctx)
 	struct mem_input *mi = pipe_ctx->plane_res.mi;
 	struct dc_cursor_mi_param param = {
 		.pixel_clk_khz = pipe_ctx->stream->timing.pix_clk_100hz / 10,
-		.ref_clk_khz = pipe_ctx->stream->ctx->dc->res_pool->ref_clock_inKhz,
+		.ref_clk_khz = pipe_ctx->stream->ctx->dc->res_pool->ref_clocks.xtalin_clock_inKhz,
 		.viewport = pipe_ctx->plane_res.scl_data.viewport,
 		.h_scale_ratio = pipe_ctx->plane_res.scl_data.ratios.horz,
 		.v_scale_ratio = pipe_ctx->plane_res.scl_data.ratios.vert,

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c

@@ -65,7 +65,7 @@ void print_microsec(struct dc_context *dc_ctx,
 	struct dc_log_buffer_ctx *log_ctx,
 	uint32_t ref_cycle)
 {
-	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clock_inKhz / 1000;
+	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000;
 	static const unsigned int frac = 1000;
 	uint32_t us_x10 = (ref_cycle * frac) / ref_clk_mhz;
 
@@ -2453,7 +2453,7 @@ static void dcn10_prepare_bandwidth(
 
 	hubbub1_program_watermarks(dc->res_pool->hubbub,
 			&context->bw.dcn.watermarks,
-			dc->res_pool->ref_clock_inKhz / 1000,
+			dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000,
 			true);
 	dcn10_stereo_hw_frame_pack_wa(dc, context);
 
@@ -2483,7 +2483,7 @@ static void dcn10_optimize_bandwidth(
 
 	hubbub1_program_watermarks(dc->res_pool->hubbub,
 			&context->bw.dcn.watermarks,
-			dc->res_pool->ref_clock_inKhz / 1000,
+			dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000,
 			true);
 	dcn10_stereo_hw_frame_pack_wa(dc, context);
 
@@ -2703,7 +2703,7 @@ static void dcn10_set_cursor_position(struct pipe_ctx *pipe_ctx)
 	struct dpp *dpp = pipe_ctx->plane_res.dpp;
 	struct dc_cursor_mi_param param = {
 		.pixel_clk_khz = pipe_ctx->stream->timing.pix_clk_100hz / 10,
-		.ref_clk_khz = pipe_ctx->stream->ctx->dc->res_pool->ref_clock_inKhz,
+		.ref_clk_khz = pipe_ctx->stream->ctx->dc->res_pool->ref_clocks.dchub_ref_clock_inKhz,
 		.viewport = pipe_ctx->plane_res.scl_data.viewport,
 		.h_scale_ratio = pipe_ctx->plane_res.scl_data.ratios.horz,
 		.v_scale_ratio = pipe_ctx->plane_res.scl_data.ratios.vert,

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer_debug.c

@@ -77,7 +77,7 @@ static unsigned int dcn10_get_hubbub_state(struct dc *dc, char *pBuf, unsigned i
 	unsigned int chars_printed = 0;
 	unsigned int remaining_buffer = bufSize;
 
-	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clock_inKhz / 1000;
+	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000;
 	static const unsigned int frac = 1000;
 
 	memset(&wm, 0, sizeof(struct dcn_hubbub_wm));
@@ -115,7 +115,7 @@ static unsigned int dcn10_get_hubp_states(struct dc *dc, char *pBuf, unsigned in
 	unsigned int chars_printed = 0;
 	unsigned int remaining_buffer = bufSize;
 
-	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clock_inKhz / 1000;
+	const uint32_t ref_clk_mhz = dc_ctx->dc->res_pool->ref_clocks.dchub_ref_clock_inKhz / 1000;
 	static const unsigned int frac = 1000;
 
 	if (invarOnly)

drivers/gpu/drm/amd/display/dc/inc/core_types.h

@@ -155,7 +155,11 @@ struct resource_pool {
 	unsigned int underlay_pipe_index;
 	unsigned int stream_enc_count;
 
-	unsigned int ref_clock_inKhz;
+	struct {
+		unsigned int xtalin_clock_inKhz;
+		unsigned int dccg_ref_clock_inKhz;
+		unsigned int dchub_ref_clock_inKhz;
+	} ref_clocks;
 	unsigned int timing_generator_count;
 
 	/*

drivers/gpu/drm/amd/display/dc/inc/hw/dccg.h

@@ -39,6 +39,9 @@ struct dccg_funcs {
 	void (*update_dpp_dto)(struct dccg *dccg,
 			int dpp_inst,
 			int req_dppclk);
+	void (*get_dccg_ref_freq)(struct dccg *dccg,
+			unsigned int xtalin_freq_inKhz,
+			unsigned int *dccg_ref_freq_inKhz);
 };
 
 #endif //__DAL_DCCG_H__

drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h

@@ -73,6 +73,10 @@ struct hubbub_funcs {
 
 	void (*wm_read_state)(struct hubbub *hubbub,
 			struct dcn_hubbub_wm *wm);
+
+	void (*get_dchub_ref_freq)(struct hubbub *hubbub,
+			unsigned int dccg_ref_freq_inKhz,
+			unsigned int *dchub_ref_freq_inKhz);
 };
 
 struct hubbub {