drm/amd/display: fix invalid reg access on DCN35 FPGA

[Why]
Unguarded SMU and CLK IP access cause issue on FPGA

[How]
Guard them for FPGA environment
Reviewed-by: Sung joon Kim <sungjoon.kim@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Eric Yang <eric.yang@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/dcn35/dcn35_clk_mgr.c

@@ -408,13 +408,12 @@ static void dcn35_dump_clk_registers(struct clk_state_registers_and_bypass *regs
 		struct clk_mgr_dcn35 *clk_mgr)
 {
 }
-void dcn35_init_clocks(struct clk_mgr *clk_mgr)
+
+static void init_clk_states(struct clk_mgr *clk_mgr)
 {
 	uint32_t ref_dtbclk = clk_mgr->clks.ref_dtbclk_khz;
-
 	memset(&(clk_mgr->clks), 0, sizeof(struct dc_clocks));
 
-	// Assumption is that boot state always supports pstate
 	clk_mgr->clks.dtbclk_en = true;
 	clk_mgr->clks.ref_dtbclk_khz = ref_dtbclk;	// restore ref_dtbclk
 	clk_mgr->clks.p_state_change_support = true;
@@ -422,6 +421,11 @@ void dcn35_init_clocks(struct clk_mgr *clk_mgr)
 	clk_mgr->clks.pwr_state = DCN_PWR_STATE_UNKNOWN;
 	clk_mgr->clks.zstate_support = DCN_ZSTATE_SUPPORT_UNKNOWN;
 }
+
+void dcn35_init_clocks(struct clk_mgr *clk_mgr)
+{
+	init_clk_states(clk_mgr);
+}
 static struct clk_bw_params dcn35_bw_params = {
 	.vram_type = Ddr4MemType,
 	.num_channels = 1,
@@ -883,7 +887,7 @@ static uint32_t dcn35_get_idle_state(struct clk_mgr *clk_mgr_base)
 
 static void dcn35_init_clocks_fpga(struct clk_mgr *clk_mgr)
 {
-	dcn35_init_clocks(clk_mgr);
+	init_clk_states(clk_mgr);
 
 /* TODO: Implement the functions and remove the ifndef guard */
 }

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_smu.c

@@ -447,6 +447,9 @@ void dcn35_smu_set_dtbclk(struct clk_mgr_internal *clk_mgr, bool enable)
 
 void dcn35_vbios_smu_enable_48mhz_tmdp_refclk_pwrdwn(struct clk_mgr_internal *clk_mgr, bool enable)
 {
+	if (!clk_mgr->smu_present)
+		return;
+
 	dcn35_smu_send_msg_with_param(
 			clk_mgr,
 			VBIOSSMC_MSG_EnableTmdp48MHzRefclkPwrDown,
@@ -458,6 +461,9 @@ int dcn35_smu_exit_low_power_state(struct clk_mgr_internal *clk_mgr)
 {
 	int retv;
 
+	if (!clk_mgr->smu_present)
+		return 0;
+
 	retv = dcn35_smu_send_msg_with_param(
 		clk_mgr,
 		VBIOSSMC_MSG_DispPsrExit,
@@ -470,6 +476,9 @@ int dcn35_smu_get_ips_supported(struct clk_mgr_internal *clk_mgr)
 {
 	int retv;
 
+	if (!clk_mgr->smu_present)
+		return 0;
+
 	retv = dcn35_smu_send_msg_with_param(
 			clk_mgr,
 			VBIOSSMC_MSG_QueryIPS2Support,
@@ -481,6 +490,9 @@ int dcn35_smu_get_ips_supported(struct clk_mgr_internal *clk_mgr)
 
 void dcn35_smu_write_ips_scratch(struct clk_mgr_internal *clk_mgr, uint32_t param)
 {
+	if (!clk_mgr->smu_present)
+		return;
+
 	REG_WRITE(MP1_SMN_C2PMSG_71, param);
 	//smu_print("%s: write_ips_scratch = %x\n", __func__, param);
 }
@@ -489,6 +501,9 @@ uint32_t dcn35_smu_read_ips_scratch(struct clk_mgr_internal *clk_mgr)
 {
 	uint32_t retv;
 
+	if (!clk_mgr->smu_present)
+		return 0;
+
 	retv = REG_READ(MP1_SMN_C2PMSG_71);
 	//smu_print("%s: dcn35_smu_read_ips_scratch = %x\n",  __func__, retv);
 	return retv;