Add UCLASS_TEE for Trusted Execution Environment
Adds a uclass to interface with a TEE (Trusted Execution Environment).
A TEE driver is a driver that interfaces with a trusted OS running in
some secure environment, for example, TrustZone on ARM cpus, or a
separate secure co-processor etc.
The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.
The over all design is based on the TEE subsystem in the Linux kernel,
tailored for U-Boot.
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 6b4d00a..dac76e0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -629,6 +629,12 @@
S: Orphaned (Since 2016-02)
T: git git://git.denx.de/u-boot-tq-group.git
+TEE
+M: Jens Wiklander <jens.wiklander@linaro.org>
+S: Maintained
+F: drivers/tee/
+F: include/tee.h
+
UBI
M: Kyungmin Park <kmpark@infradead.org>
M: Heiko Schocher <hs@denx.de>
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 11b88a1..927a2b8 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -100,6 +100,8 @@
source "drivers/sysreset/Kconfig"
+source "drivers/tee/Kconfig"
+
source "drivers/thermal/Kconfig"
source "drivers/timer/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index e3b9e8c..fb38b67 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -105,6 +105,7 @@
obj-y += smem/
obj-y += soc/
obj-y += thermal/
+obj-$(CONFIG_TEE) += tee/
obj-y += axi/
obj-$(CONFIG_W1) += w1/
obj-$(CONFIG_W1_EEPROM) += w1-eeprom/
diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
new file mode 100644
index 0000000..f3fc3c2
--- /dev/null
+++ b/drivers/tee/Kconfig
@@ -0,0 +1,11 @@
+# Generic Trusted Execution Environment Configuration
+config TEE
+ bool "Trusted Execution Environment support"
+ depends on ARM && (ARM64 || CPU_V7A)
+ select ARM_SMCCC
+ help
+ This implements a generic interface towards a Trusted Execution
+ Environment (TEE). A TEE is a trusted OS running in some secure
+ environment, for example, TrustZone on ARM cpus, or a separate
+ secure co-processor etc. See also:
+ https://en.wikipedia.org/wiki/Trusted_execution_environment
diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
new file mode 100644
index 0000000..b6d8e16
--- /dev/null
+++ b/drivers/tee/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+obj-y += tee-uclass.o
diff --git a/drivers/tee/tee-uclass.c b/drivers/tee/tee-uclass.c
new file mode 100644
index 0000000..1bee54e
--- /dev/null
+++ b/drivers/tee/tee-uclass.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2018 Linaro Limited
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/uclass-internal.h>
+#include <tee.h>
+
+/**
+ * struct tee_uclass_priv - information of a TEE, stored by the uclass
+ *
+ * @list_shm: list of structe tee_shm representing memory blocks shared
+ * with the TEE.
+ */
+struct tee_uclass_priv {
+ struct list_head list_shm;
+};
+
+static const struct tee_driver_ops *tee_get_ops(struct udevice *dev)
+{
+ return device_get_ops(dev);
+}
+
+void tee_get_version(struct udevice *dev, struct tee_version_data *vers)
+{
+ tee_get_ops(dev)->get_version(dev, vers);
+}
+
+int tee_open_session(struct udevice *dev, struct tee_open_session_arg *arg,
+ uint num_param, struct tee_param *param)
+{
+ return tee_get_ops(dev)->open_session(dev, arg, num_param, param);
+}
+
+int tee_close_session(struct udevice *dev, u32 session)
+{
+ return tee_get_ops(dev)->close_session(dev, session);
+}
+
+int tee_invoke_func(struct udevice *dev, struct tee_invoke_arg *arg,
+ uint num_param, struct tee_param *param)
+{
+ return tee_get_ops(dev)->invoke_func(dev, arg, num_param, param);
+}
+
+int __tee_shm_add(struct udevice *dev, ulong align, void *addr, ulong size,
+ u32 flags, struct tee_shm **shmp)
+{
+ struct tee_shm *shm;
+ void *p = addr;
+ int rc;
+
+ if (flags & TEE_SHM_ALLOC) {
+ if (align)
+ p = memalign(align, size);
+ else
+ p = malloc(size);
+ }
+ if (!p)
+ return -ENOMEM;
+
+ shm = calloc(1, sizeof(*shm));
+ if (!shm) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ shm->dev = dev;
+ shm->addr = p;
+ shm->size = size;
+ shm->flags = flags;
+
+ if (flags & TEE_SHM_SEC_REGISTER) {
+ rc = tee_get_ops(dev)->shm_register(dev, shm);
+ if (rc)
+ goto err;
+ }
+
+ if (flags & TEE_SHM_REGISTER) {
+ struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+
+ list_add(&shm->link, &priv->list_shm);
+ }
+
+ *shmp = shm;
+
+ return 0;
+err:
+ free(shm);
+ if (flags & TEE_SHM_ALLOC)
+ free(p);
+
+ return rc;
+}
+
+int tee_shm_alloc(struct udevice *dev, ulong size, u32 flags,
+ struct tee_shm **shmp)
+{
+ u32 f = flags;
+
+ f |= TEE_SHM_SEC_REGISTER | TEE_SHM_REGISTER | TEE_SHM_ALLOC;
+
+ return __tee_shm_add(dev, 0, NULL, size, f, shmp);
+}
+
+int tee_shm_register(struct udevice *dev, void *addr, ulong size, u32 flags,
+ struct tee_shm **shmp)
+{
+ u32 f = flags & ~TEE_SHM_ALLOC;
+
+ f |= TEE_SHM_SEC_REGISTER | TEE_SHM_REGISTER;
+
+ return __tee_shm_add(dev, 0, addr, size, f, shmp);
+}
+
+void tee_shm_free(struct tee_shm *shm)
+{
+ if (!shm)
+ return;
+
+ if (shm->flags & TEE_SHM_SEC_REGISTER)
+ tee_get_ops(shm->dev)->shm_unregister(shm->dev, shm);
+
+ if (shm->flags & TEE_SHM_REGISTER)
+ list_del(&shm->link);
+
+ if (shm->flags & TEE_SHM_ALLOC)
+ free(shm->addr);
+
+ free(shm);
+}
+
+bool tee_shm_is_registered(struct tee_shm *shm, struct udevice *dev)
+{
+ struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+ struct tee_shm *s;
+
+ list_for_each_entry(s, &priv->list_shm, link)
+ if (s == shm)
+ return true;
+
+ return false;
+}
+
+struct udevice *tee_find_device(struct udevice *start,
+ int (*match)(struct tee_version_data *vers,
+ const void *data),
+ const void *data,
+ struct tee_version_data *vers)
+{
+ struct udevice *dev = start;
+ struct tee_version_data lv;
+ struct tee_version_data *v = vers ? vers : &lv;
+
+ if (!dev)
+ uclass_find_first_device(UCLASS_TEE, &dev);
+ else
+ uclass_find_next_device(&dev);
+
+ for (; dev; uclass_find_next_device(&dev)) {
+ if (device_probe(dev))
+ continue;
+ tee_get_ops(dev)->get_version(dev, v);
+ if (!match || match(v, data))
+ return dev;
+ }
+
+ return NULL;
+}
+
+static int tee_pre_probe(struct udevice *dev)
+{
+ struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+
+ INIT_LIST_HEAD(&priv->list_shm);
+
+ return 0;
+}
+
+static int tee_pre_remove(struct udevice *dev)
+{
+ struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+ struct tee_shm *shm;
+
+ /*
+ * Any remaining shared memory must be unregistered now as U-Boot
+ * is about to hand over to the next stage and that memory will be
+ * reused.
+ */
+ while (!list_empty(&priv->list_shm)) {
+ shm = list_first_entry(&priv->list_shm, struct tee_shm, link);
+ debug("%s: freeing leftover shm %p (size %lu, flags %#x)\n",
+ __func__, (void *)shm, shm->size, shm->flags);
+ tee_shm_free(shm);
+ }
+
+ return 0;
+}
+
+UCLASS_DRIVER(tee) = {
+ .id = UCLASS_TEE,
+ .name = "tee",
+ .per_device_auto_alloc_size = sizeof(struct tee_uclass_priv),
+ .pre_probe = tee_pre_probe,
+ .pre_remove = tee_pre_remove,
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 79fd300..269a2c6 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -85,6 +85,7 @@
UCLASS_SPI_GENERIC, /* Generic SPI flash target */
UCLASS_SYSCON, /* System configuration device */
UCLASS_SYSRESET, /* System reset device */
+ UCLASS_TEE, /* Trusted Execution Environment device */
UCLASS_THERMAL, /* Thermal sensor */
UCLASS_TIMER, /* Timer device */
UCLASS_TPM, /* Trusted Platform Module TIS interface */
diff --git a/include/tee.h b/include/tee.h
new file mode 100644
index 0000000..b86dbec
--- /dev/null
+++ b/include/tee.h
@@ -0,0 +1,336 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2018 Linaro Limited
+ */
+
+#ifndef __TEE_H
+#define __TEE_H
+
+#define TEE_UUID_LEN 16
+
+#define TEE_GEN_CAP_GP BIT(0) /* GlobalPlatform compliant TEE */
+#define TEE_GEN_CAP_REG_MEM BIT(1) /* Supports registering shared memory */
+
+#define TEE_SHM_REGISTER BIT(0) /* In list of shared memory */
+#define TEE_SHM_SEC_REGISTER BIT(1) /* TEE notified of this memory */
+#define TEE_SHM_ALLOC BIT(2) /* The memory is malloced() and must */
+ /* be freed() */
+
+#define TEE_PARAM_ATTR_TYPE_NONE 0 /* parameter not used */
+#define TEE_PARAM_ATTR_TYPE_VALUE_INPUT 1
+#define TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT 2
+#define TEE_PARAM_ATTR_TYPE_VALUE_INOUT 3 /* input and output */
+#define TEE_PARAM_ATTR_TYPE_MEMREF_INPUT 5
+#define TEE_PARAM_ATTR_TYPE_MEMREF_OUTPUT 6
+#define TEE_PARAM_ATTR_TYPE_MEMREF_INOUT 7 /* input and output */
+#define TEE_PARAM_ATTR_TYPE_MASK 0xff
+#define TEE_PARAM_ATTR_META 0x100
+#define TEE_PARAM_ATTR_MASK (TEE_PARAM_ATTR_TYPE_MASK | \
+ TEE_PARAM_ATTR_META)
+
+/*
+ * Some Global Platform error codes which has a meaning if the
+ * TEE_GEN_CAP_GP bit is returned by the driver in
+ * struct tee_version_data::gen_caps
+ */
+#define TEE_SUCCESS 0x00000000
+#define TEE_ERROR_GENERIC 0xffff0000
+#define TEE_ERROR_BAD_PARAMETERS 0xffff0006
+#define TEE_ERROR_ITEM_NOT_FOUND 0xffff0008
+#define TEE_ERROR_NOT_IMPLEMENTED 0xffff0009
+#define TEE_ERROR_NOT_SUPPORTED 0xffff000a
+#define TEE_ERROR_COMMUNICATION 0xffff000e
+#define TEE_ERROR_SECURITY 0xffff000f
+#define TEE_ERROR_OUT_OF_MEMORY 0xffff000c
+#define TEE_ERROR_TARGET_DEAD 0xffff3024
+
+#define TEE_ORIGIN_COMMS 0x00000002
+#define TEE_ORIGIN_TEE 0x00000003
+#define TEE_ORIGIN_TRUSTED_APP 0x00000004
+
+struct udevice;
+/**
+ * struct tee_shm - memory shared with the TEE
+ * @dev: The TEE device
+ * @link: List node in the list in struct struct tee_uclass_priv
+ * @addr: Pointer to the shared memory
+ * @size: Size of the the shared memory
+ * @flags: TEE_SHM_* above
+ */
+struct tee_shm {
+ struct udevice *dev;
+ struct list_head link;
+ void *addr;
+ ulong size;
+ u32 flags;
+};
+
+/**
+ * struct tee_param_memref - memory reference for a Trusted Application
+ * @shm_offs: Offset in bytes into the shared memory object @shm
+ * @size: Size in bytes of the memory reference
+ * @shm: Pointer to a shared memory object for the buffer
+ *
+ * Used as a part of struct tee_param, see that for more information.
+ */
+struct tee_param_memref {
+ ulong shm_offs;
+ ulong size;
+ struct tee_shm *shm;
+};
+
+/**
+ * struct tee_param_value - value parameter for a Trusted Application
+ * @a, @b, @c: Parameters passed by value
+ *
+ * Used as a part of struct tee_param, see that for more information.
+ */
+struct tee_param_value {
+ u64 a;
+ u64 b;
+ u64 c;
+};
+
+/**
+ * struct tee_param - invoke parameter for a Trusted Application
+ * @attr: Attributes
+ * @u.memref: Memref parameter if (@attr & TEE_PARAM_ATTR_MASK) is one of
+ * TEE_PARAM_ATTR_TYPE_MEMREF_* above
+ * @u.value: Value parameter if (@attr & TEE_PARAM_ATTR_MASK) is one of
+ * TEE_PARAM_ATTR_TYPE_VALUE_* above
+ *
+ * Parameters to TA are passed using an array of this struct, for
+ * flexibility both value parameters and memory refereces can be used.
+ */
+struct tee_param {
+ u64 attr;
+ union {
+ struct tee_param_memref memref;
+ struct tee_param_value value;
+ } u;
+};
+
+/**
+ * struct tee_open_session_arg - extra arguments for tee_open_session()
+ * @uuid: [in] UUID of the Trusted Application
+ * @clnt_uuid: [in] Normally zeroes
+ * @clnt_login: [in] Normally 0
+ * @session: [out] Session id
+ * @ret: [out] return value
+ * @ret_origin: [out] origin of the return value
+ */
+struct tee_open_session_arg {
+ u8 uuid[TEE_UUID_LEN];
+ u8 clnt_uuid[TEE_UUID_LEN];
+ u32 clnt_login;
+ u32 session;
+ u32 ret;
+ u32 ret_origin;
+};
+
+/**
+ * struct tee_invoke_arg - extra arguments for tee_invoke_func()
+ * @func: [in] Trusted Application function, specific to the TA
+ * @session: [in] Session id, from open session
+ * @ret: [out] return value
+ * @ret_origin: [out] origin of the return value
+ */
+struct tee_invoke_arg {
+ u32 func;
+ u32 session;
+ u32 ret;
+ u32 ret_origin;
+};
+
+/**
+ * struct tee_version_data - description of TEE
+ * @gen_caps: Generic capabilities, TEE_GEN_CAP_* above
+ */
+struct tee_version_data {
+ u32 gen_caps;
+};
+
+/**
+ * struct tee_driver_ops - TEE driver operations
+ * @get_version: Query capabilities of TEE device,
+ * @open_session: Opens a session to a Trusted Application in the TEE,
+ * @close_session: Closes a session to Trusted Application,
+ * @invoke_func: Invokes a function in a Trusted Application,
+ * @shm_register: Registers memory shared with the TEE
+ * @shm_unregister: Unregisters memory shared with the TEE
+ */
+struct tee_driver_ops {
+ /**
+ * get_version() - Query capabilities of TEE device
+ * @dev: The TEE device
+ * @vers: Pointer to version data
+ */
+ void (*get_version)(struct udevice *dev, struct tee_version_data *vers);
+ /**
+ * open_session() - Open a session to a Trusted Application
+ * @dev: The TEE device
+ * @arg: Open session arguments
+ * @num_param: Number of elements in @param
+ * @param: Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result. If @arg->ret is
+ * TEE_SUCCESS the session identifier is available in @arg->session.
+ */
+ int (*open_session)(struct udevice *dev,
+ struct tee_open_session_arg *arg, uint num_param,
+ struct tee_param *param);
+ /**
+ * close_session() - Close a session to a Trusted Application
+ * @dev: The TEE device
+ * @session: Session id
+ *
+ * Return < 0 on error else 0, regardless the session will not be valid
+ * after this function has returned.
+ */
+ int (*close_session)(struct udevice *dev, u32 session);
+ /**
+ * tee_invoke_func() - Invoke a function in a Trusted Application
+ * @dev: The TEE device
+ * @arg: Invoke arguments
+ * @num_param: Number of elements in @param
+ * @param: Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result.
+ */
+ int (*invoke_func)(struct udevice *dev, struct tee_invoke_arg *arg,
+ uint num_param, struct tee_param *param);
+ /**
+ * shm_register() - Registers memory shared with the TEE
+ * @dev: The TEE device
+ * @shm: Pointer to a shared memory object
+ * Returns 0 on success or < 0 on failure.
+ */
+ int (*shm_register)(struct udevice *dev, struct tee_shm *shm);
+ /**
+ * shm_unregister() - Unregisters memory shared with the TEE
+ * @dev: The TEE device
+ * @shm: Pointer to a shared memory object
+ * Returns 0 on success or < 0 on failure.
+ */
+ int (*shm_unregister)(struct udevice *dev, struct tee_shm *shm);
+};
+
+/**
+ * __tee_shm_add() - Internal helper function to register shared memory
+ * @dev: The TEE device
+ * @align: Required alignment of allocated memory block if
+ * (@flags & TEE_SHM_ALLOC)
+ * @addr: Address of memory block, ignored if (@flags & TEE_SHM_ALLOC)
+ * @size: Size of memory block
+ * @flags: TEE_SHM_* above
+ * @shmp: If the function return 0, this holds the allocated
+ * struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int __tee_shm_add(struct udevice *dev, ulong align, void *addr, ulong size,
+ u32 flags, struct tee_shm **shmp);
+
+/**
+ * tee_shm_alloc() - Allocate shared memory
+ * @dev: The TEE device
+ * @size: Size of memory block
+ * @flags: TEE_SHM_* above
+ * @shmp: If the function return 0, this holds the allocated
+ * struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int tee_shm_alloc(struct udevice *dev, ulong size, u32 flags,
+ struct tee_shm **shmp);
+
+/**
+ * tee_shm_register() - Registers shared memory
+ * @dev: The TEE device
+ * @addr: Address of memory block
+ * @size: Size of memory block
+ * @flags: TEE_SHM_* above
+ * @shmp: If the function return 0, this holds the allocated
+ * struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int tee_shm_register(struct udevice *dev, void *addr, ulong size, u32 flags,
+ struct tee_shm **shmp);
+
+/**
+ * tee_shm_free() - Frees shared memory
+ * @shm: Shared memory object
+ */
+void tee_shm_free(struct tee_shm *shm);
+
+/**
+ * tee_shm_is_registered() - Check register status of shared memory object
+ * @shm: Pointer to shared memory object
+ * @dev: The TEE device
+ *
+ * Returns true if the shared memory object is registered for the supplied
+ * TEE device
+ */
+bool tee_shm_is_registered(struct tee_shm *shm, struct udevice *dev);
+
+/**
+ * tee_find_device() - Look up a TEE device
+ * @start: if not NULL, continue search after this device
+ * @match: function to check TEE device, returns != 0 if the device
+ * matches
+ * @data: data for match function
+ * @vers: if not NULL, version data of TEE device of the device returned
+ *
+ * Returns a probed TEE device of the first TEE device matched by the
+ * match() callback or NULL.
+ */
+struct udevice *tee_find_device(struct udevice *start,
+ int (*match)(struct tee_version_data *vers,
+ const void *data),
+ const void *data,
+ struct tee_version_data *vers);
+
+/**
+ * tee_get_version() - Query capabilities of TEE device
+ * @dev: The TEE device
+ * @vers: Pointer to version data
+ */
+void tee_get_version(struct udevice *dev, struct tee_version_data *vers);
+
+/**
+ * tee_open_session() - Open a session to a Trusted Application
+ * @dev: The TEE device
+ * @arg: Open session arguments
+ * @num_param: Number of elements in @param
+ * @param: Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result. If @arg->ret is
+ * TEE_SUCCESS the session identifier is available in @arg->session.
+ */
+int tee_open_session(struct udevice *dev, struct tee_open_session_arg *arg,
+ uint num_param, struct tee_param *param);
+
+/**
+ * tee_close_session() - Close a session to a Trusted Application
+ * @dev: The TEE device
+ * @session: Session id
+ *
+ * Return < 0 on error else 0, regardless the session will not be valid
+ * after this function has returned.
+ */
+int tee_close_session(struct udevice *dev, u32 session);
+
+/**
+ * tee_invoke_func() - Invoke a function in a Trusted Application
+ * @dev: The TEE device
+ * @arg: Invoke arguments
+ * @num_param: Number of elements in @param
+ * @param: Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result.
+ */
+int tee_invoke_func(struct udevice *dev, struct tee_invoke_arg *arg,
+ uint num_param, struct tee_param *param);
+
+#endif /* __TEE_H */