u-boot/arch/arm/cpu/armv7/sunxi/tzpc.c
Chen-Yu Tsai 92369844ec sunxi: Enable non-secure access to RTC on sun6i (A31s)
On the A31s the RTC is by default secured. Thus when u-boot
loads the kernel in non-secure world, the RTC is unavailable. The
SoC has a TrustZone Protection Controller, which can be used to
enable non-secure access to the RTC.

On the A31 the TZPC doesn't seem to do anything, i.e. changes to
its register contents do not affect access to the RTC.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-08-31 08:43:42 +02:00

18 lines
411 B
C

/*
* (C) Copyright 2015 Chen-Yu Tsai <wens@csie.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm/io.h>
#include <asm/arch/cpu.h>
#include <asm/arch/tzpc.h>
/* Configure Trust Zone Protection Controller */
void tzpc_init(void)
{
struct sunxi_tzpc *tzpc = (struct sunxi_tzpc *)SUNXI_TZPC_BASE;
/* Enable non-secure access to the RTC */
writel(SUNXI_TZPC_DECPORT0_RTC, &tzpc->decport0_set);
}