drm/amd/display: Add debug option for disabling SLDO optimizations

[Why]
DM can hook this up to disable SLDO optimizations in firmware during
DMCUB initialization for debug purposes.

[How]
Add the option and pass it through dmub_srv.
Reviewed-by: Hansen Dsouza <hansen.dsouza@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dmub/dmub_srv.h

@@ -299,6 +299,7 @@ struct dmub_srv_hw_params {
 	enum dmub_memory_access_type mem_access_type;
 	enum dmub_ips_disable_type disable_ips;
 	bool disallow_phy_access;
+	bool disable_sldo_opt;
 };
 
 /**

drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h

@@ -684,7 +684,8 @@ union dmub_fw_boot_options {
 		uint32_t ips_pg_disable: 1; /* 1 to disable ONO domains power gating*/
 		uint32_t ips_disable: 3; /* options to disable ips support*/
 		uint32_t ips_sequential_ono: 1; /**< 1 to enable sequential ONO IPS sequence */
-		uint32_t reserved : 8; /**< reserved */
+		uint32_t disable_sldo_opt: 1; /**< 1 to disable SLDO optimizations */
+		uint32_t reserved : 7; /**< reserved */
 	} bits; /**< boot bits */
 	uint32_t all; /**< 32-bit access to bits */
 };

drivers/gpu/drm/amd/display/dmub/src/dmub_dcn35.c

@@ -424,6 +424,7 @@ void dmub_dcn35_enable_dmub_boot_options(struct dmub_srv *dmub, const struct dmu
 	boot_options.bits.disable_clk_gate = params->disable_clock_gate;
 	boot_options.bits.ips_disable = params->disable_ips;
 	boot_options.bits.ips_sequential_ono = params->ips_sequential_ono;
+	boot_options.bits.disable_sldo_opt = params->disable_sldo_opt;
 
 	REG_WRITE(DMCUB_SCRATCH14, boot_options.all);
 }