drm/amd/display: Send DTBCLK disable message on first commit

[Why]
Previous patch to allow DTBCLK disable didn't address boot case. Driver
thinks DTBCLK is disabled by default, so we don't send disable message to
PMFW. DTBCLK is then enabled at idle desktop on boot, burning power.

[How]
Set dtbclk_en to true on boot so that disable message is sent during first
commit.

Fixes: 27750e1 ("drm/amd/display: Allow DTBCLK disable for DCN35")
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Taimur Hassan <syed.hassan@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Author: Taimur Hassan

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c

@@ -73,6 +73,8 @@
 #define CLK1_CLK2_BYPASS_CNTL__CLK2_BYPASS_SEL_MASK		0x00000007L
 #define CLK1_CLK2_BYPASS_CNTL__CLK2_BYPASS_DIV_MASK		0x000F0000L
 
+#define SMU_VER_THRESHOLD 0x5D4A00 //93.74.0
+
 #define REG(reg_name) \
 	(ctx->clk_reg_offsets[reg ## reg_name ## _BASE_IDX] + reg ## reg_name)
 
@@ -411,9 +413,12 @@ static void dcn35_dump_clk_registers(struct clk_state_registers_and_bypass *regs
 
 static void init_clk_states(struct clk_mgr *clk_mgr)
 {
+	struct clk_mgr_internal *clk_mgr_int = TO_CLK_MGR_INTERNAL(clk_mgr);
 	uint32_t ref_dtbclk = clk_mgr->clks.ref_dtbclk_khz;
 	memset(&(clk_mgr->clks), 0, sizeof(struct dc_clocks));
 
+	if (clk_mgr_int->smu_ver >= SMU_VER_THRESHOLD)
+		clk_mgr->clks.dtbclk_en = true; // request DTBCLK disable on first commit
 	clk_mgr->clks.ref_dtbclk_khz = ref_dtbclk;	// restore ref_dtbclk
 	clk_mgr->clks.p_state_change_support = true;
 	clk_mgr->clks.prev_p_state_change_support = true;