soc/amd/cezanne: add downcoring and SMT disable settings to devicetree

BUG=b:184162768
TEST=none

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: Id03454ed2be242bce9497560c089f75046ed7e32
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52197
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/cezanne/chip.h

@@ -15,6 +15,18 @@ struct soc_amd_cezanne_config {
 
 	/* Enable S0iX support */
 	bool s0ix_enable;
+
+	enum {
+		DOWNCORE_AUTO = 0,
+		DOWNCORE_1 = 1, /* Run with 1 physical core */
+		DOWNCORE_2 = 3, /* Run with 2 physical cores */
+		DOWNCORE_3 = 4, /* Run with 3 physical cores */
+		DOWNCORE_4 = 6, /* Run with 4 physical cores */
+		DOWNCORE_5 = 8, /* Run with 5 physical cores */
+		DOWNCORE_6 = 9, /* Run with 6 physical cores */
+		DOWNCORE_7 = 10, /* Run with 7 physical cores */
+	} downcore_mode;
+	bool disable_smt; /* disable second thread on all physical cores */
 };
 
 #endif /* CEZANNE_CHIP_H */