--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Intel Corporation.
+ * Take from coreboot project file of the same name
+ */
+
+#include <common.h>
+#include <asm/intel_regs.h>
+#include <asm/io.h>
+#include <asm/arch/systemagent.h>
+
+void enable_bios_reset_cpl(void)
+{
+ /*
+ * Set bits 0+1 of BIOS_RESET_CPL to indicate to the CPU
+ * that BIOS has initialised memory and power management
+ *
+ * The FSP-S does not do this. If we leave this as zero then I believe
+ * the power-aware interrupts don't work in Linux, and CPU 0 always gets
+ * the interrupt.
+ */
+ setbits_8(MCHBAR_REG(BIOS_RESET_CPL), 3);
+}
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2017 Intel Corporation.
+ * Take from coreboot project file of the same name
+ */
+
+#ifndef _ASM_ARCH_SYSTEMAGENT_H
+#define _ASM_ARCH_SYSTEMAGENT_H
+
+/* Device 0:0.0 PCI configuration space */
+#define MCHBAR 0x48
+
+/* RAPL Package Power Limit register under MCHBAR */
+#define PUNIT_THERMAL_DEVICE_IRQ 0x700C
+#define PUINT_THERMAL_DEVICE_IRQ_VEC_NUMBER 0x18
+#define PUINT_THERMAL_DEVICE_IRQ_LOCK 0x80000000
+#define BIOS_RESET_CPL 0x7078
+#define PCODE_INIT_DONE BIT(8)
+#define MCHBAR_RAPL_PPL 0x70A8
+#define CORE_DISABLE_MASK 0x7168
+#define CAPID0_A 0xE4
+#define VTD_DISABLE BIT(23)
+#define DEFVTBAR 0x6c80
+#define GFXVTBAR 0x6c88
+#define VTBAR_ENABLED 0x01
+#define VTBAR_MASK GENMASK_ULL(39, 12)
+#define VTBAR_SIZE 0x1000
+
+/**
+ * enable_bios_reset_cpl() - Tell the system agent that memory/power are ready
+ *
+ * This should be called when U-Boot has set up the memory and power
+ * management.
+ */
+void enable_bios_reset_cpl(void);
+
+#endif