soc/amd/picasso: Add controls for SMT and downcoring

BUG=b:159198385
TEST=confirm both using Mandolin

Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Change-Id: I91654817608ab62e4104959b8876333911b90175
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43299
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/picasso/chip.h

@@ -93,6 +93,14 @@ struct soc_amd_picasso_config {
 	/* PROCHOT_L de-assertion Ramp Time */
 	uint32_t prochot_l_deassertion_ramp_time;
 
+	enum {
+		DOWNCORE_AUTO = 0,
+		DOWNCORE_1 = 1, /* Run with single core */
+		DOWNCORE_2 = 3, /* Run with two cores */
+		DOWNCORE_3 = 4, /* Run with three cores */
+	} downcore_mode;
+	uint8_t smt_disable; /* 1=disable SMT, 0=enable SMT */
+
 	/* Lower die temperature limit */
 	uint32_t thermctl_limit;
 

src/soc/amd/picasso/romstage.c

@@ -43,6 +43,9 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 		mcfg->stapm_time_constant = config->stapm_time_constant;
 	}
 
+	mcfg->ccx_down_core_mode = config->downcore_mode;
+	mcfg->ccx_disable_smt = config->smt_disable;
+
 	mcfg->sustained_power_limit = config->sustained_power_limit;
 	mcfg->prochot_l_deassertion_ramp_time = config->prochot_l_deassertion_ramp_time;
 	mcfg->thermctl_limit = config->thermctl_limit;