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>

1 files changed, 23 insertions, 0 deletions

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 0000000000..ba4d43bc3a
--- /dev/null
+++ b/arch/arm/include/asm/arch-sunxi/tzpc.h
@@ -0,0 +1,23 @@
+/*
+ * (C) Copyright 2015 Chen-Yu Tsai <wens@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 */