[U-Boot] [PATCH] sunxi: Enable non-secure access to RTC on sun6i (A31s)

[Hans de Goede]

Hi,

On 25-08-15 04:49, Chen-Yu Tsai wrote:
> 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 at csie.org>

Thanks I've queued this up in my tree, and it will be
part of my next pull-req for u-boot/master.

Regards,

Hans

> ---
>   arch/arm/cpu/armv7/sunxi/Makefile      |  1 +
>   arch/arm/cpu/armv7/sunxi/board.c       |  5 +++++
>   arch/arm/cpu/armv7/sunxi/tzpc.c        | 18 ++++++++++++++++++
>   arch/arm/include/asm/arch-sunxi/tzpc.h | 23 +++++++++++++++++++++++
>   4 files changed, 47 insertions(+)
>   create mode 100644 arch/arm/cpu/armv7/sunxi/tzpc.c
>   create mode 100644 arch/arm/include/asm/arch-sunxi/tzpc.h
>
> diff --git a/arch/arm/cpu/armv7/sunxi/Makefile b/arch/arm/cpu/armv7/sunxi/Makefile
> index 76c7e55..459d5d8 100644
> --- a/arch/arm/cpu/armv7/sunxi/Makefile
> +++ b/arch/arm/cpu/armv7/sunxi/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_MACH_SUN6I)	+= clock_sun6i.o
>   obj-$(CONFIG_MACH_SUN7I)	+= clock_sun4i.o
>   obj-$(CONFIG_MACH_SUN8I)	+= clock_sun6i.o
>   obj-$(CONFIG_MACH_SUN9I)	+= clock_sun9i.o
> +obj-$(CONFIG_MACH_SUN6I)	+= tzpc.o
>
>   obj-$(CONFIG_AXP152_POWER)	+= pmic_bus.o
>   obj-$(CONFIG_AXP209_POWER)	+= pmic_bus.o
> diff --git a/arch/arm/cpu/armv7/sunxi/board.c b/arch/arm/cpu/armv7/sunxi/board.c
> index f01846e..b40198b 100644
> --- a/arch/arm/cpu/armv7/sunxi/board.c
> +++ b/arch/arm/cpu/armv7/sunxi/board.c
> @@ -23,6 +23,7 @@
>   #include <asm/arch/gpio.h>
>   #include <asm/arch/sys_proto.h>
>   #include <asm/arch/timer.h>
> +#include <asm/arch/tzpc.h>
>   #include <asm/arch/mmc.h>
>
>   #include <linux/compiler.h>
> @@ -115,6 +116,10 @@ void s_init(void)
>   		"orr r0, r0, #1 << 6\n"
>   		"mcr p15, 0, r0, c1, c0, 1\n");
>   #endif
> +#if defined CONFIG_MACH_SUN6I
> +	/* Enable non-secure access to the RTC */
> +	tzpc_init();
> +#endif
>
>   	clock_init();
>   	timer_init();
> diff --git a/arch/arm/cpu/armv7/sunxi/tzpc.c b/arch/arm/cpu/armv7/sunxi/tzpc.c
> new file mode 100644
> index 0000000..5c9c69b
> --- /dev/null
> +++ b/arch/arm/cpu/armv7/sunxi/tzpc.c
> @@ -0,0 +1,18 @@
> +/*
> + * (C) Copyright 2015 Chen-Yu Tsai <wens at 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);
> +}
> diff --git a/arch/arm/include/asm/arch-sunxi/tzpc.h b/arch/arm/include/asm/arch-sunxi/tzpc.h
> new file mode 100644
> index 0000000..ba4d43b
> --- /dev/null
> +++ b/arch/arm/include/asm/arch-sunxi/tzpc.h
> @@ -0,0 +1,23 @@
> +/*
> + * (C) Copyright 2015 Chen-Yu Tsai <wens at csie.org>
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#ifndef _SUNXI_TZPC_H
> +#define _SUNXI_TZPC_H
> +
> +#ifndef __ASSEMBLY__
> +struct sunxi_tzpc {
> +	u32 r0size;		/* 0x00 Size of secure RAM region */
> +	u32 decport0_status;	/* 0x04 Status of decode protection port 0 */
> +	u32 decport0_set;	/* 0x08 Set decode protection port 0 */
> +	u32 decport0_clear;	/* 0x0c Clear decode protection port 0 */
> +};
> +#endif
> +
> +#define SUNXI_TZPC_DECPORT0_RTC	(1 << 1)
> +
> +void tzpc_init(void);
> +
> +#endif /* _SUNXI_TZPC_H */
>