1 files changed, 164 insertions, 0 deletions
diff --git a/plat/arm/css/drivers/scp/css_pm_scpi.c b/plat/arm/css/drivers/scp/css_pm_scpi.c
new file mode 100644
index 00000000..545c3fbe
--- /dev/null
+++ b/plat/arm/css/drivers/scp/css_pm_scpi.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch_helpers.h>
+#include <assert.h>
+#include <css_pm.h>
+#include <debug.h>
+#include <plat_arm.h>
+#include "../scpi/css_scpi.h"
+#include "css_scp.h"
+
+/*
+ * This file implements the SCP power management functions using SCPI protocol.
+ */
+
+/*
+ * Helper function to inform power down state to SCP.
+ */
+void css_scp_suspend(const psci_power_state_t *target_state)
+{
+	uint32_t cluster_state = scpi_power_on;
+	uint32_t system_state = scpi_power_on;
+
+	/* Check if power down at system power domain level is requested */
+	if (CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
+		system_state = scpi_power_retention;
+
+	/* Cluster is to be turned off, so disable coherency */
+	if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
+		cluster_state = scpi_power_off;
+
+	/*
+	 * Ask the SCP to power down the appropriate components depending upon
+	 * their state.
+	 */
+	scpi_set_css_power_state(read_mpidr_el1(),
+				 scpi_power_off,
+				 cluster_state,
+				 system_state);
+}
+
+/*
+ * Helper function to turn off a CPU power domain and its parent power domains
+ * if applicable. Since SCPI doesn't differentiate between OFF and suspend, we
+ * call the suspend helper here.
+ */
+void css_scp_off(const psci_power_state_t *target_state)
+{
+	css_scp_suspend(target_state);
+}
+
+/*
+ * Helper function to turn ON a CPU power domain and its parent power domains
+ * if applicable.
+ */
+void css_scp_on(u_register_t mpidr)
+{
+	/*
+	 * SCP takes care of powering up parent power domains so we
+	 * only need to care about level 0
+	 */
+	scpi_set_css_power_state(mpidr, scpi_power_on, scpi_power_on,
+				 scpi_power_on);
+}
+
+/*
+ * Helper function to get the power state of a power domain node as reported
+ * by the SCP.
+ */
+int css_scp_get_power_state(u_register_t mpidr, unsigned int power_level)
+{
+	int rc, element;
+	unsigned int cpu_state, cluster_state;
+
+	/*
+	 * The format of 'power_level' is implementation-defined, but 0 must
+	 * mean a CPU. We also allow 1 to denote the cluster
+	 */
+	if (power_level != ARM_PWR_LVL0 && power_level != ARM_PWR_LVL1)
+		return PSCI_E_INVALID_PARAMS;
+
+	/* Query SCP */
+	rc = scpi_get_css_power_state(mpidr, &cpu_state, &cluster_state);
+	if (rc != 0)
+		return PSCI_E_INVALID_PARAMS;
+
+	/* Map power states of CPU and cluster to expected PSCI return codes */
+	if (power_level == ARM_PWR_LVL0) {
+		/*
+		 * The CPU state returned by SCP is an 8-bit bit mask
+		 * corresponding to each CPU in the cluster
+		 */
+#if ARM_PLAT_MT
+		/*
+		 * The current SCPI driver only caters for single-threaded
+		 * platforms. Hence we ignore the thread ID (which is always 0)
+		 * for such platforms.
+		 */
+		element = (mpidr >> MPIDR_AFF1_SHIFT) & MPIDR_AFFLVL_MASK;
+#else
+		element = mpidr & MPIDR_AFFLVL_MASK;
+#endif  /* ARM_PLAT_MT */
+		return CSS_CPU_PWR_STATE(cpu_state, element) ==
+			CSS_CPU_PWR_STATE_ON ? HW_ON : HW_OFF;
+	} else {
+		assert(cluster_state == CSS_CLUSTER_PWR_STATE_ON ||
+				cluster_state == CSS_CLUSTER_PWR_STATE_OFF);
+		return cluster_state == CSS_CLUSTER_PWR_STATE_ON ? HW_ON :
+			HW_OFF;
+	}
+}
+
+/*
+ * Helper function to shutdown the system via SCPI.
+ */
+void __dead2 css_scp_sys_shutdown(void)
+{
+	uint32_t response;
+
+	/*
+	 * Disable GIC CPU interface to prevent pending interrupt
+	 * from waking up the AP from WFI.
+	 */
+	plat_arm_gic_cpuif_disable();
+
+	/* Send the power down request to the SCP */
+	response = scpi_sys_power_state(scpi_system_shutdown);
+
+	if (response != SCP_OK) {
+		ERROR("CSS System Off: SCP error %u.\n", response);
+		panic();
+	}
+	wfi();
+	ERROR("CSS System Off: operation not handled.\n");
+	panic();
+}
+
+/*
+ * Helper function to reset the system via SCPI.
+ */
+void __dead2 css_scp_sys_reboot(void)
+{
+	uint32_t response;
+
+	/*
+	 * Disable GIC CPU interface to prevent pending interrupt
+	 * from waking up the AP from WFI.
+	 */
+	plat_arm_gic_cpuif_disable();
+
+	/* Send the system reset request to the SCP */
+	response = scpi_sys_power_state(scpi_system_reboot);
+
+	if (response != SCP_OK) {
+		ERROR("CSS System Reset: SCP error %u.\n", response);
+		panic();
+	}
+	wfi();
+	ERROR("CSS System Reset: operation not handled.\n");
+	panic();
+}