drm/amd/display: fix dcn315 memory channel count and width read

[Why & How]
Correctly set ddr5 channel width to 8 bytes
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c

@@ -556,8 +556,7 @@ static void dcn315_clk_mgr_helper_populate_bw_params(
 	ASSERT(bw_params->clk_table.entries[i-1].dcfclk_mhz);
 	bw_params->vram_type = bios_info->memory_type;
 	bw_params->num_channels = bios_info->ma_channel_number;
-	if (!bw_params->num_channels)
-		bw_params->num_channels = 2;
+	bw_params->dram_channel_width_bytes = bios_info->memory_type == 0x22 ? 8 : 4;
 
 	for (i = 0; i < WM_SET_COUNT; i++) {
 		bw_params->wm_table.entries[i].wm_inst = i;

drivers/gpu/drm/amd/display/dc/dml/dcn31/dcn31_fpu.c

@@ -291,6 +291,7 @@ static struct _vcs_dpi_soc_bounding_box_st dcn3_15_soc = {
 	.do_urgent_latency_adjustment = false,
 	.urgent_latency_adjustment_fabric_clock_component_us = 0,
 	.urgent_latency_adjustment_fabric_clock_reference_mhz = 0,
+	.num_chans = 4,
 };
 
 struct _vcs_dpi_ip_params_st dcn3_16_ip = {
@@ -680,7 +681,11 @@ void dcn315_update_bw_bounding_box(struct dc *dc, struct clk_bw_params *bw_param
 
 	dcn3_15_ip.max_num_otg = dc->res_pool->res_cap->num_timing_generator;
 	dcn3_15_ip.max_num_dpp = dc->res_pool->pipe_count;
+
+	if (bw_params->num_channels > 0)
 		dcn3_15_soc.num_chans = bw_params->num_channels;
+	if (bw_params->dram_channel_width_bytes > 0)
+		dcn3_15_soc.dram_channel_width_bytes = bw_params->dram_channel_width_bytes;
 
 	ASSERT(clk_table->num_entries);