drivers: marvell: mc_trustzone: add driver for mc trustzone

Add simple driver which allows to configure the memory controller trust
zones. It is responsible for opening mc trustzone window, with
appropriate base address, size and attributes.

Example of usage in upcoming commits.

Change-Id: I8bea17754d31451b305040ee7de331fb8db0c63f
Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Reviewed-by: Kostya Porotchkin <kostap@marvell.com>

drivers/marvell/mc_trustzone/mc_trustzone.c

+/*
+ * Copyright (C) 2018 Marvell International Ltd.
+ *
+ * SPDX-License-Identifier:     BSD-3-Clause
+ * https://spdx.org/licenses
+ */
+
+#include <addr_map.h>
+#include <debug.h>
+#include <mmio.h>
+#include <mvebu_def.h>
+#include "mc_trustzone.h"
+
+#define TZ_SIZE(x)		((x) >> 13)
+
+static int fls(int x)
+{
+	if (!x)
+		return 0;
+
+	return 32 - __builtin_clz(x);
+}
+
+/* To not duplicate types, the addr_map_win is used, but the "target"
+ * filed is referring to attributes instead of "target".
+ */
+void tz_enable_win(int ap_index, const struct addr_map_win *win, int win_id)
+{
+	int tz_size;
+	uint32_t val, base = win->base_addr;
+
+	if ((win_id < 0) || (win_id > MVEBU_TZ_MAX_WINS)) {
+		ERROR("Enabling wrong MC TrustZone window %d!\n", win_id);
+		return;
+	}
+
+	/* map the window size to trustzone register convention */
+	tz_size = fls(TZ_SIZE(win->win_size));
+
+	VERBOSE("%s: window size = 0x%llx maps to tz_size %d\n",
+		__func__, win->win_size, tz_size);
+	if (tz_size < 0 || tz_size > 31) {
+		ERROR("Using not allowed size for MC TrustZone window %d!\n",
+		      win_id);
+		return;
+	}
+
+	if (base & 0xfff) {
+		base = base & ~0xfff;
+		WARN("Attempt to open MC TZ win. at 0x%llx, truncate to 0x%x\n",
+		     win->base_addr, base);
+	}
+
+	val = base | (tz_size << 7) | win->target_id | TZ_VALID;
+
+	VERBOSE("%s: base 0x%x, tz_size moved 0x%x, attr 0x%x, val 0x%x\n",
+		__func__, base, (tz_size << 7), win->target_id, val);
+
+	mmio_write_32(MVEBU_AP_MC_TRUSTZONE_REG_LOW(ap_index, win_id), val);
+
+	VERBOSE("%s: Win%d[0x%x] configured to 0x%x\n", __func__, win_id,
+		MVEBU_AP_MC_TRUSTZONE_REG_LOW(ap_index, win_id),
+		mmio_read_32(MVEBU_AP_MC_TRUSTZONE_REG_LOW(ap_index, win_id)));
+
+	mmio_write_32(MVEBU_AP_MC_TRUSTZONE_REG_HIGH(ap_index, win_id),
+		     (win->base_addr >> 32));
+
+	VERBOSE("%s: Win%d[0x%x] configured to 0x%x\n", __func__, win_id,
+		MVEBU_AP_MC_TRUSTZONE_REG_HIGH(ap_index, win_id),
+		mmio_read_32(MVEBU_AP_MC_TRUSTZONE_REG_HIGH(ap_index, win_id)));
+}

drivers/marvell/mc_trustzone/mc_trustzone.h

+/*
+ * Copyright (C) 2018 Marvell International Ltd.
+ *
+ * SPDX-License-Identifier:     BSD-3-Clause
+ * https://spdx.org/licenses
+ */
+
+#ifndef _MC_TRUSTZONE_H
+#define _MC_TRUSTZONE_H
+
+#include <addr_map.h>
+
+#define MVEBU_TZ_MAX_WINS	16
+
+#define TZ_VALID		(1 << 0)
+#define TZ_PERM(x)		((x) << 1)
+#define TZ_RZ_ENABLE		(1 << 3)
+
+/* tz attr definitions */
+#define TZ_PERM_RW		(TZ_PERM(0))
+#define TZ_PERM_RO		(TZ_PERM(1))
+#define TZ_PERM_WO		(TZ_PERM(2))
+#define TZ_PERM_ABORT		(TZ_PERM(3))
+
+void tz_enable_win(int ap_index, const struct addr_map_win *win, int win_id);
+
+#endif /* _MC_TRUSTZONE_H */