drm/amd/display: add mechanism to skip DCN init

[Why]
If optimized init is done in FW. DCN init can be skipped in driver. This
need to be communicated between driver and fw and maintain backwards
compatibility.

[How]
Use DMUB scratch 0 bit 2 to indicate optimized init done in fw and
use DMUB scatch 4 bit 0 to indicate drive supports the optimized flow
so FW will perform it.
Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@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/core/dc.c

@@ -4267,9 +4267,6 @@ void dc_set_power_state(
 
 		dc_z10_restore(dc);
 
-		if (dc->ctx->dmub_srv)
-			dc_dmub_srv_wait_phy_init(dc->ctx->dmub_srv);
-
 		dc->hwss.init_hw(dc);
 
 		if (dc->hwss.init_sys_ctx != NULL &&

drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c

@@ -179,31 +179,17 @@ bool dc_dmub_srv_cmd_run_list(struct dc_dmub_srv *dc_dmub_srv, unsigned int coun
 	return true;
 }
 
-void dc_dmub_srv_wait_phy_init(struct dc_dmub_srv *dc_dmub_srv)
+bool dc_dmub_srv_optimized_init_done(struct dc_dmub_srv *dc_dmub_srv)
 {
-	struct dmub_srv *dmub = dc_dmub_srv->dmub;
-	struct dc_context *dc_ctx = dc_dmub_srv->ctx;
-	enum dmub_status status;
-
-	for (;;) {
-		/* Wait up to a second for PHY init. */
-		status = dmub_srv_wait_for_phy_init(dmub, 1000000);
-		if (status == DMUB_STATUS_OK)
-			/* Initialization OK */
-			break;
+	struct dmub_srv *dmub;
+	union dmub_fw_boot_status status;
 
-		DC_ERROR("DMCUB PHY init failed: status=%d\n", status);
-		ASSERT(0);
+	if (!dc_dmub_srv || !dc_dmub_srv->dmub)
+		return false;
 
-		if (status != DMUB_STATUS_TIMEOUT)
-			/*
-			 * Server likely initialized or we don't have
-			 * DMCUB HW support - this won't end.
-			 */
-			break;
+	dmub = dc_dmub_srv->dmub;
 
-		/* Continue spinning so we don't hang the ASIC. */
-	}
+	return status.bits.optimized_init_done;
 }
 
 bool dc_dmub_srv_notify_stream_mask(struct dc_dmub_srv *dc_dmub_srv,

drivers/gpu/drm/amd/display/dc/dc_dmub_srv.h

@@ -54,7 +54,7 @@ struct dc_dmub_srv {
 
 void dc_dmub_srv_wait_idle(struct dc_dmub_srv *dc_dmub_srv);
 
-void dc_dmub_srv_wait_phy_init(struct dc_dmub_srv *dc_dmub_srv);
+bool dc_dmub_srv_optimized_init_done(struct dc_dmub_srv *dc_dmub_srv);
 
 bool dc_dmub_srv_cmd_run(struct dc_dmub_srv *dc_dmub_srv, union dmub_rb_cmd *cmd, enum dm_dmub_wait_type wait_type);
 

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

@@ -1524,7 +1524,9 @@ void dcn10_init_hw(struct dc *dc)
 	if (!dcb->funcs->is_accelerated_mode(dcb))
 		hws->funcs.disable_vga(dc->hwseq);
 
-	hws->funcs.bios_golden_init(dc);
+	if (!dc_dmub_srv_optimized_init_done(dc->ctx->dmub_srv))
+		hws->funcs.bios_golden_init(dc);
+
 
 	if (dc->ctx->dc_bios->fw_info_valid) {
 		res_pool->ref_clocks.xtalin_clock_inKhz =

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

@@ -366,7 +366,6 @@ struct dmub_srv_hw_funcs {
 
 	bool (*is_hw_init)(struct dmub_srv *dmub);
 
-	bool (*is_phy_init)(struct dmub_srv *dmub);
 	void (*enable_dmub_boot_options)(struct dmub_srv *dmub,
 				const struct dmub_srv_hw_params *params);
 

drivers/gpu/drm/amd/display/dmub/src/dmub_dcn21.c

@@ -54,9 +54,3 @@ const struct dmub_srv_common_regs dmub_srv_dcn21_regs = {
 #undef DMUB_SF
 };
 
-/* Shared functions. */
-
-bool dmub_dcn21_is_phy_init(struct dmub_srv *dmub)
-{
-	return REG_READ(DMCUB_SCRATCH10) == 0;
-}

drivers/gpu/drm/amd/display/dmub/src/dmub_dcn21.h

@@ -32,8 +32,4 @@
 
 extern const struct dmub_srv_common_regs dmub_srv_dcn21_regs;
 
-/* Hardware functions. */
-
-bool dmub_dcn21_is_phy_init(struct dmub_srv *dmub);
-
 #endif /* _DMUB_DCN21_H_ */

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

@@ -190,11 +190,9 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 
 		funcs->get_diagnostic_data = dmub_dcn20_get_diagnostic_data;
 
-		if (asic == DMUB_ASIC_DCN21) {
+		if (asic == DMUB_ASIC_DCN21)
 			dmub->regs = &dmub_srv_dcn21_regs;
 
-			funcs->is_phy_init = dmub_dcn21_is_phy_init;
-		}
 		if (asic == DMUB_ASIC_DCN30) {
 			dmub->regs = &dmub_srv_dcn30_regs;
 
@@ -721,27 +719,6 @@ enum dmub_status dmub_srv_wait_for_auto_load(struct dmub_srv *dmub,
 	return DMUB_STATUS_TIMEOUT;
 }
 
-enum dmub_status dmub_srv_wait_for_phy_init(struct dmub_srv *dmub,
-					    uint32_t timeout_us)
-{
-	uint32_t i = 0;
-
-	if (!dmub->hw_init)
-		return DMUB_STATUS_INVALID;
-
-	if (!dmub->hw_funcs.is_phy_init)
-		return DMUB_STATUS_OK;
-
-	for (i = 0; i <= timeout_us; i += 10) {
-		if (dmub->hw_funcs.is_phy_init(dmub))
-			return DMUB_STATUS_OK;
-
-		udelay(10);
-	}
-
-	return DMUB_STATUS_TIMEOUT;
-}
-
 enum dmub_status dmub_srv_wait_for_idle(struct dmub_srv *dmub,
 					uint32_t timeout_us)
 {