Add TrustZone (TZC-400) driver
The TZC-400 performs security checks on transactions to memory or
peripherals. Separate regions can be created in the address space each
with individual security settings.
Limitations:
This driver does not currently support raising an interrupt on access
violation.
Change-Id: Idf8ed64b4d8d218fc9b6f9d75acdb2cd441d2449
diff --git a/drivers/arm/interconnect/tzc-400/tzc400.c b/drivers/arm/interconnect/tzc-400/tzc400.c
new file mode 100644
index 0000000..b88e34a
--- /dev/null
+++ b/drivers/arm/interconnect/tzc-400/tzc400.c
@@ -0,0 +1,265 @@
+/*
+ * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include "arch_helpers.h"
+#include "tzc400.h"
+#include "mmio.h"
+#include "debug.h"
+
+static uint32_t tzc_read_build_config(uint64_t base)
+{
+ return mmio_read_32(base + BUILD_CONFIG_OFF);
+}
+
+static uint32_t tzc_read_gate_keeper(uint64_t base)
+{
+ return mmio_read_32(base + GATE_KEEPER_OFF);
+}
+
+static void tzc_write_gate_keeper(uint64_t base, uint32_t val)
+{
+ mmio_write_32(base + GATE_KEEPER_OFF, val);
+}
+
+static void tzc_write_action(uint64_t base, enum tzc_action action)
+{
+ mmio_write_32(base + ACTION_OFF, action);
+}
+
+static void tzc_write_region_base_low(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_BASE_LOW_OFF + REGION_NUM_OFF(region), val);
+}
+
+static void tzc_write_region_base_high(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_BASE_HIGH_OFF + REGION_NUM_OFF(region), val);
+}
+
+static void tzc_write_region_top_low(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_TOP_LOW_OFF + REGION_NUM_OFF(region), val);
+}
+
+static void tzc_write_region_top_high(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_TOP_HIGH_OFF + REGION_NUM_OFF(region), val);
+}
+
+static void tzc_write_region_attributes(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_ATTRIBUTES_OFF + REGION_NUM_OFF(region), val);
+}
+
+static void tzc_write_region_id_access(uint64_t base, uint32_t region, uint32_t val)
+{
+ mmio_write_32(base + REGION_ID_ACCESS_OFF + REGION_NUM_OFF(region), val);
+}
+
+static uint32_t tzc_read_component_id(uint64_t base)
+{
+ uint32_t id;
+
+ id = mmio_read_8(base + CID0_OFF);
+ id |= (mmio_read_8(base + CID1_OFF) << 8);
+ id |= (mmio_read_8(base + CID2_OFF) << 16);
+ id |= (mmio_read_8(base + CID3_OFF) << 24);
+
+ return id;
+}
+
+static uint32_t tzc_get_gate_keeper(uint64_t base, uint8_t filter)
+{
+ uint32_t tmp;
+
+ tmp = (tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
+ GATE_KEEPER_OS_MASK;
+
+ return tmp >> filter;
+}
+
+/* This function is not MP safe. */
+static void tzc_set_gate_keeper(uint64_t base, uint8_t filter, uint32_t val)
+{
+ uint32_t tmp;
+
+ /* Upper half is current state. Lower half is requested state. */
+ tmp = (tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
+ GATE_KEEPER_OS_MASK;
+
+ if (val)
+ tmp |= (1 << filter);
+ else
+ tmp &= ~(1 << filter);
+
+ tzc_write_gate_keeper(base, (tmp & GATE_KEEPER_OR_MASK) <<
+ GATE_KEEPER_OR_SHIFT);
+
+ /* Wait here until we see the change reflected in the TZC status. */
+ while (((tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
+ GATE_KEEPER_OS_MASK) != tmp)
+ ;
+}
+
+
+void tzc_init(struct tzc_instance *controller)
+{
+ uint32_t tzc_id, tzc_build;
+
+ assert(controller != NULL);
+
+ /*
+ * We expect to see a tzc400. Check component ID. The TZC-400 TRM shows
+ * component ID is expected to be "0xB105F00D".
+ */
+ tzc_id = tzc_read_component_id(controller->base);
+ if (tzc_id != TZC400_COMPONENT_ID) {
+ ERROR("TZC : Wrong device ID (0x%x).\n", tzc_id);
+ panic();
+ }
+
+ /* Save values we will use later. */
+ tzc_build = tzc_read_build_config(controller->base);
+ controller->num_filters = ((tzc_build >> BUILD_CONFIG_NF_SHIFT) &
+ BUILD_CONFIG_NF_MASK) + 1;
+ controller->addr_width = ((tzc_build >> BUILD_CONFIG_AW_SHIFT) &
+ BUILD_CONFIG_AW_MASK) + 1;
+ controller->num_regions = ((tzc_build >> BUILD_CONFIG_NR_SHIFT) &
+ BUILD_CONFIG_NR_MASK) + 1;
+}
+
+
+/*
+ * `tzc_configure_region` is used to program regions into the TrustZone
+ * controller. A region can be associated with more than one filter. The
+ * associated filters are passed in as a bitmap (bit0 = filter0).
+ * NOTE:
+ * The region 0 covers the whole address space and is enabled on all filters,
+ * this cannot be changed. It is, however, possible to change some region 0
+ * permissions.
+ */
+void tzc_configure_region(const struct tzc_instance *controller,
+ uint32_t filters,
+ uint8_t region,
+ uint64_t region_base,
+ uint64_t region_top,
+ enum tzc_region_attributes sec_attr,
+ uint32_t ns_device_access)
+{
+ uint64_t max_addr;
+
+ assert(controller != NULL);
+
+ /* Do range checks on filters and regions. */
+ assert(((filters >> controller->num_filters) == 0) &&
+ (region < controller->num_regions));
+
+ /*
+ * Do address range check based on TZC configuration. A 64bit address is
+ * the max and expected case.
+ */
+ max_addr = UINT64_MAX >> (64 - controller->addr_width);
+ if ((region_top > max_addr) || (region_base >= region_top))
+ assert(0);
+
+ /* region_base and (region_top + 1) must be 4KB aligned */
+ assert(((region_base | (region_top + 1)) & (4096 - 1)) == 0);
+
+ assert(sec_attr <= TZC_REGION_S_RDWR);
+
+ /*
+ * Inputs look ok, start programming registers.
+ * All the address registers are 32 bits wide and have a LOW and HIGH
+ * component used to construct a up to a 64bit address.
+ */
+ tzc_write_region_base_low(controller->base, region, (uint32_t)(region_base));
+ tzc_write_region_base_high(controller->base, region, (uint32_t)(region_base >> 32));
+
+ tzc_write_region_top_low(controller->base, region, (uint32_t)(region_top));
+ tzc_write_region_top_high(controller->base, region, (uint32_t)(region_top >> 32));
+
+ /* Assign the region to a filter and set secure attributes */
+ tzc_write_region_attributes(controller->base, region,
+ (sec_attr << REGION_ATTRIBUTES_SEC_SHIFT) | filters);
+
+ /*
+ * Specify which non-secure devices have permission to access this
+ * region.
+ */
+ tzc_write_region_id_access(controller->base, region, ns_device_access);
+}
+
+
+void tzc_set_action(const struct tzc_instance *controller, enum tzc_action action)
+{
+ assert(controller != NULL);
+
+ /*
+ * - Currently no handler is provided to trap an error via interrupt
+ * or exception.
+ * - The interrupt action has not been tested.
+ */
+ tzc_write_action(controller->base, action);
+}
+
+
+void tzc_enable_filters(const struct tzc_instance *controller)
+{
+ uint32_t state;
+ uint32_t filter;
+
+ assert(controller != NULL);
+
+ for (filter = 0; filter < controller->num_filters; filter++) {
+ state = tzc_get_gate_keeper(controller->base, filter);
+ if (state) {
+ ERROR("TZC : Filter %d Gatekeeper already enabled.\n",
+ filter);
+ panic();
+ }
+ tzc_set_gate_keeper(controller->base, filter, 1);
+ }
+}
+
+
+void tzc_disable_filters(const struct tzc_instance *controller)
+{
+ uint32_t filter;
+
+ assert(controller != NULL);
+
+ /*
+ * We don't do the same state check as above as the Gatekeepers are
+ * disabled after reset.
+ */
+ for (filter = 0; filter < controller->num_filters; filter++)
+ tzc_set_gate_keeper(controller->base, filter, 0);
+}