u-boot/arch/x86/cpu/apollolake/systemagent.c
Simon Glass bd47209743 x86: apl: Add systemagent driver
This driver handles communication with the systemagent which needs to be
told when U-Boot has completed its init.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-12-15 11:44:27 +08:00

23 lines
614 B
C

// 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);
}