diff --git a/plat/allwinner/sun50i_a64/sunxi_power.c b/plat/allwinner/sun50i_a64/sunxi_power.c
index a2110e9..452450d 100644
--- a/plat/allwinner/sun50i_a64/sunxi_power.c
+++ b/plat/allwinner/sun50i_a64/sunxi_power.c
@@ -7,18 +7,110 @@
 
 #include <arch_helpers.h>
 #include <debug.h>
+#include <delay_timer.h>
+#include <errno.h>
+#include <mmio.h>
+#include <platform_def.h>
+#include <sunxi_def.h>
+#include <sunxi_mmap.h>
+
+static enum pmic_type {
+	GENERIC_H5,
+	GENERIC_A64,
+} pmic;
+
+/*
+ * On boards without a proper PMIC we struggle to turn off the system properly.
+ * Try to turn off as much off the system as we can, to reduce power
+ * consumption. This should be entered with only one core running and SMP
+ * disabled.
+ * This function only cares about peripherals.
+ */
+void sunxi_turn_off_soc(uint16_t socid)
+{
+	int i;
+
+	/** Turn off most peripherals, most importantly DRAM users. **/
+	/* Keep DRAM controller running for now. */
+	mmio_clrbits_32(SUNXI_CCU_BASE + 0x2c0, ~BIT_32(14));
+	mmio_clrbits_32(SUNXI_CCU_BASE + 0x60, ~BIT_32(14));
+	/* Contains msgbox (bit 21) and spinlock (bit 22) */
+	mmio_write_32(SUNXI_CCU_BASE + 0x2c4, 0);
+	mmio_write_32(SUNXI_CCU_BASE + 0x64, 0);
+	mmio_write_32(SUNXI_CCU_BASE + 0x2c8, 0);
+	/* Keep PIO controller running for now. */
+	mmio_clrbits_32(SUNXI_CCU_BASE + 0x68, ~(BIT_32(5)));
+	mmio_write_32(SUNXI_CCU_BASE + 0x2d0, 0);
+	/* Contains UART0 (bit 16) */
+	mmio_write_32(SUNXI_CCU_BASE + 0x2d8, 0);
+	mmio_write_32(SUNXI_CCU_BASE + 0x6c, 0);
+	mmio_write_32(SUNXI_CCU_BASE + 0x70, 0);
+
+	/** Turn off DRAM controller. **/
+	mmio_clrbits_32(SUNXI_CCU_BASE + 0x2c0, BIT_32(14));
+	mmio_clrbits_32(SUNXI_CCU_BASE + 0x60, BIT_32(14));
+
+	/** Migrate CPU and bus clocks away from the PLLs. **/
+	/* AHB1: use OSC24M/1, APB1 = AHB1 / 2 */
+	mmio_write_32(SUNXI_CCU_BASE + 0x54, 0x1000);
+	/* APB2: use OSC24M */
+	mmio_write_32(SUNXI_CCU_BASE + 0x58, 0x1000000);
+	/* AHB2: use AHB1 clock */
+	mmio_write_32(SUNXI_CCU_BASE + 0x5c, 0);
+	/* CPU: use OSC24M */
+	mmio_write_32(SUNXI_CCU_BASE + 0x50, 0x10000);
+
+	/** Turn off PLLs. **/
+	for (i = 0; i < 6; i++)
+		mmio_clrbits_32(SUNXI_CCU_BASE + i * 8, BIT(31));
+	switch (socid) {
+	case SUNXI_SOC_H5:
+		mmio_clrbits_32(SUNXI_CCU_BASE + 0x44, BIT(31));
+		break;
+	case SUNXI_SOC_A64:
+		mmio_clrbits_32(SUNXI_CCU_BASE + 0x2c, BIT(31));
+		mmio_clrbits_32(SUNXI_CCU_BASE + 0x4c, BIT(31));
+		break;
+	}
+}
 
 int sunxi_pmic_setup(uint16_t socid)
 {
-	/* STUB */
-	NOTICE("BL31: STUB PMIC setup code called\n");
-
+	switch (socid) {
+	case SUNXI_SOC_H5:
+		pmic = GENERIC_H5;
+		break;
+	case SUNXI_SOC_A64:
+		pmic = GENERIC_A64;
+		break;
+	default:
+		NOTICE("BL31: PMIC: No support for Allwinner %x SoC.\n", socid);
+		return -ENODEV;
+	}
 	return 0;
 }
 
 void __dead2 sunxi_power_down(void)
 {
-	ERROR("PSCI: Full shutdown not implemented, halting\n");
+	switch (pmic) {
+	case GENERIC_H5:
+		/* Turn off as many peripherals and clocks as we can. */
+		sunxi_turn_off_soc(SUNXI_SOC_H5);
+		/* Turn off the pin controller now. */
+		mmio_write_32(SUNXI_CCU_BASE + 0x68, 0);
+		break;
+	case GENERIC_A64:
+		/* Turn off as many peripherals and clocks as we can. */
+		sunxi_turn_off_soc(SUNXI_SOC_A64);
+		/* Turn off the pin controller now. */
+		mmio_write_32(SUNXI_CCU_BASE + 0x68, 0);
+		break;
+	default:
+		break;
+	}
+
+	udelay(1000);
+	ERROR("PSCI: Cannot turn off system, halting.\n");
 	wfi();
 	panic();
 }