Merge "Provide a hint to power controller for DSU cluster power down" into integration

include/arch/aarch32/arch.h

@@ -701,4 +701,14 @@
 #define AMEVTYPER1E	p15, 0, c13, c15, 6
 #define AMEVTYPER1F	p15, 0, c13, c15, 7
 
+/*******************************************************************************
+ * Definitions for DynamicIQ Shared Unit registers
+ ******************************************************************************/
+#define CLUSTERPWRDN	p15, 0, c15, c3, 6
+
+/* CLUSTERPWRDN register definitions */
+#define DSU_CLUSTER_PWR_OFF	0
+#define DSU_CLUSTER_PWR_ON	1
+#define DSU_CLUSTER_PWR_MASK	U(1)
+
 #endif /* ARCH_H */

include/arch/aarch32/arch_helpers.h

@@ -336,6 +336,11 @@ DEFINE_DCOP_PARAM_FUNC(cvac, DCCIMVAC)
 DEFINE_DCOP_PARAM_FUNC(cvac, DCCMVAC)
 #endif
 
+/*
+ * DynamIQ Shared Unit power management
+ */
+DEFINE_COPROCR_RW_FUNCS(clusterpwrdn, CLUSTERPWRDN)
+
 /* Previously defined accessor functions with incomplete register names  */
 #define dsb()			dsbsy()
 #define dmb()			dmbsy()

include/arch/aarch64/arch.h

@@ -947,4 +947,14 @@
 #define RGSR_EL1		S3_0_C1_C0_5
 #define GCR_EL1			S3_0_C1_C0_6
 
+/*******************************************************************************
+ * Definitions for DynamicIQ Shared Unit registers
+ ******************************************************************************/
+#define CLUSTERPWRDN_EL1	S3_0_c15_c3_6
+
+/* CLUSTERPWRDN_EL1 register definitions */
+#define DSU_CLUSTER_PWR_OFF	0
+#define DSU_CLUSTER_PWR_ON	1
+#define DSU_CLUSTER_PWR_MASK	U(1)
+
 #endif /* ARCH_H */

include/arch/aarch64/arch_helpers.h

@@ -520,6 +520,9 @@ DEFINE_RENAME_SYSREG_RW_FUNCS(tfsr_el1, TFSR_EL1)
 DEFINE_RENAME_SYSREG_RW_FUNCS(rgsr_el1, RGSR_EL1)
 DEFINE_RENAME_SYSREG_RW_FUNCS(gcr_el1, GCR_EL1)
 
+/* DynamIQ Shared Unit power management */
+DEFINE_RENAME_SYSREG_RW_FUNCS(clusterpwrdn_el1, CLUSTERPWRDN_EL1)
+
 #define IS_IN_EL(x) \
 	(GET_EL(read_CurrentEl()) == MODE_EL##x)
 
@@ -582,4 +585,7 @@ static inline uint64_t el_implemented(unsigned int el)
 #define read_cpacr()		read_cpacr_el1()
 #define write_cpacr(_v)		write_cpacr_el1(_v)
 
+#define read_clusterpwrdn()	read_clusterpwrdn_el1()
+#define write_clusterpwrdn(_v)	write_clusterpwrdn_el1(_v)
+
 #endif /* ARCH_HELPERS_H */

plat/arm/board/fvp/fvp_pm.c

@@ -64,6 +64,25 @@ static void fvp_cluster_pwrdwn_common(void)
 	/* Disable coherency if this cluster is to be turned off */
 	fvp_interconnect_disable();
 
+#if HW_ASSISTED_COHERENCY
+	uint32_t reg;
+
+	/*
+	 * If we have determined this core to be the last man standing and we
+	 * intend to power down the cluster proactively, we provide a hint to
+	 * the power controller that cluster power is not required when all
+	 * cores are powered down.
+	 * Note that this is only an advisory to power controller and is supported
+	 * by SoCs with DynamIQ Shared Units only.
+	 */
+	reg = read_clusterpwrdn();
+
+	/* Clear and set bit 0 : Cluster power not required */
+	reg &= ~DSU_CLUSTER_PWR_MASK;
+	reg |= DSU_CLUSTER_PWR_OFF;
+	write_clusterpwrdn(reg);
+#endif
+
 	/* Program the power controller to turn the cluster off */
 	fvp_pwrc_write_pcoffr(mpidr);
 }

plat/arm/css/common/css_pm.c

@@ -124,8 +124,28 @@ static void css_power_down_common(const psci_power_state_t *target_state)
 	plat_arm_gic_cpuif_disable();
 
 	/* Cluster is to be turned off, so disable coherency */
-	if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
+	if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF) {
 		plat_arm_interconnect_exit_coherency();
+
+#if HW_ASSISTED_COHERENCY
+		uint32_t reg;
+
+		/*
+		 * If we have determined this core to be the last man standing and we
+		 * intend to power down the cluster proactively, we provide a hint to
+		 * the power controller that cluster power is not required when all
+		 * cores are powered down.
+		 * Note that this is only an advisory to power controller and is supported
+		 * by SoCs with DynamIQ Shared Units only.
+		 */
+		reg = read_clusterpwrdn();
+
+		/* Clear and set bit 0 : Cluster power not required */
+		reg &= ~DSU_CLUSTER_PWR_MASK;
+		reg |= DSU_CLUSTER_PWR_OFF;
+		write_clusterpwrdn(reg);
+#endif
+	}
 }
 
 /*******************************************************************************