tee: optee: support AVB trusted application

Adds configuration option OPTEE_TA_AVB and a header file describing the
interface to the Android Verified Boot 2.0 (AVB) trusted application
provided by OP-TEE.

Tested-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Reviewed-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

MAINTAINERS

@@ -634,6 +634,7 @@ M:	Jens Wiklander <jens.wiklander@linaro.org>
 S:	Maintained
 F:	drivers/tee/
 F:	include/tee.h
+F:	include/tee/
 
 UBI
 M:	Kyungmin Park <kmpark@infradead.org>

drivers/tee/optee/Kconfig

@@ -9,3 +9,19 @@ config OPTEE
 	  mechanism. This driver can request services from OP-TEE, but also
 	  handle Remote Procedure Calls (RPC) from OP-TEE needed to
 	  execute a service. For more information see: https://www.op-tee.org
+
+if OPTEE
+
+menu "OP-TEE options"
+
+config OPTEE_TA_AVB
+	bool "Support AVB TA"
+	default y
+	help
+	  Enables support for the AVB Trusted Application (TA) in OP-TEE.
+	  The TA can support the "avb" subcommands "read_rb", "write"rb"
+	  and "is_unlocked".
+
+endmenu
+
+endif

drivers/tee/tee-uclass.c

@@ -207,3 +207,27 @@ UCLASS_DRIVER(tee) = {
 	.pre_probe = tee_pre_probe,
 	.pre_remove = tee_pre_remove,
 };
+
+void tee_optee_ta_uuid_from_octets(struct tee_optee_ta_uuid *d,
+				   const u8 s[TEE_UUID_LEN])
+{
+	d->time_low = ((u32)s[0] << 24) | ((u32)s[1] << 16) |
+		      ((u32)s[2] << 8) | s[3],
+	d->time_mid = ((u32)s[4] << 8) | s[5];
+	d->time_hi_and_version = ((u32)s[6] << 8) | s[7];
+	memcpy(d->clock_seq_and_node, s + 8, sizeof(d->clock_seq_and_node));
+}
+
+void tee_optee_ta_uuid_to_octets(u8 d[TEE_UUID_LEN],
+				 const struct tee_optee_ta_uuid *s)
+{
+	d[0] = s->time_low >> 24;
+	d[1] = s->time_low >> 16;
+	d[2] = s->time_low >> 8;
+	d[3] = s->time_low;
+	d[4] = s->time_mid >> 8;
+	d[5] = s->time_mid;
+	d[6] = s->time_hi_and_version >> 8;
+	d[7] = s->time_hi_and_version;
+	memcpy(d + 8, s->clock_seq_and_node, sizeof(s->clock_seq_and_node));
+}

include/tee.h

@@ -49,6 +49,22 @@
 #define TEE_ORIGIN_TRUSTED_APP		0x00000004
 
 struct udevice;
+
+/**
+ * struct tee_optee_ta_uuid - OP-TEE Trusted Application (TA) UUID format
+ *
+ * Used to identify an OP-TEE TA and define suitable to initialize structs
+ * of this format is distributed with the interface of the TA. The
+ * individual fields of this struct doesn't have any special meaning in
+ * OP-TEE. See RFC4122 for details on the format.
+ */
+struct tee_optee_ta_uuid {
+	u32 time_low;
+	u16 time_mid;
+	u16 time_hi_and_version;
+	u8 clock_seq_and_node[8];
+};
+
 /**
  * struct tee_shm - memory shared with the TEE
  * @dev:	The TEE device
@@ -333,4 +349,26 @@ int tee_close_session(struct udevice *dev, u32 session);
 int tee_invoke_func(struct udevice *dev, struct tee_invoke_arg *arg,
 		    uint num_param, struct tee_param *param);
 
+/**
+ * tee_optee_ta_uuid_from_octets() - Converts to struct tee_optee_ta_uuid
+ * @d:	Destination struct
+ * @s:	Source UUID octets
+ *
+ * Conversion to a struct tee_optee_ta_uuid represantion from binary octet
+ * representation.
+ */
+void tee_optee_ta_uuid_from_octets(struct tee_optee_ta_uuid *d,
+				   const u8 s[TEE_UUID_LEN]);
+
+/**
+ * tee_optee_ta_uuid_to_octets() - Converts from struct tee_optee_ta_uuid
+ * @d:	Destination UUID octets
+ * @s:	Source struct
+ *
+ * Conversion from a struct tee_optee_ta_uuid represantion to binary octet
+ * representation.
+ */
+void tee_optee_ta_uuid_to_octets(u8 d[TEE_UUID_LEN],
+				 const struct tee_optee_ta_uuid *s);
+
 #endif /* __TEE_H */

include/tee/optee_ta_avb.h

@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/* Copyright (c) 2018, Linaro Limited */
+
+#ifndef __TA_AVB_H
+#define __TA_AVB_H
+
+#define TA_AVB_UUID { 0x023f8f1a, 0x292a, 0x432b, \
+		      { 0x8f, 0xc4, 0xde, 0x84, 0x71, 0x35, 0x80, 0x67 } }
+
+#define TA_AVB_MAX_ROLLBACK_LOCATIONS	256
+
+/*
+ * Gets the rollback index corresponding to the given rollback index slot.
+ *
+ * in	params[0].value.a:	rollback index slot
+ * out	params[1].value.a:	upper 32 bits of rollback index
+ * out	params[1].value.b:	lower 32 bits of rollback index
+ */
+#define TA_AVB_CMD_READ_ROLLBACK_INDEX	0
+
+/*
+ * Updates the rollback index corresponding to the given rollback index slot.
+ *
+ * Will refuse to update a slot with a lower value.
+ *
+ * in	params[0].value.a:	rollback index slot
+ * in	params[1].value.a:	upper 32 bits of rollback index
+ * in	params[1].value.b:	lower 32 bits of rollback index
+ */
+#define TA_AVB_CMD_WRITE_ROLLBACK_INDEX	1
+
+/*
+ * Gets the lock state of the device.
+ *
+ * out	params[0].value.a:	lock state
+ */
+#define TA_AVB_CMD_READ_LOCK_STATE	2
+
+/*
+ * Sets the lock state of the device.
+ *
+ * If the lock state is changed all rollback slots will be reset to 0
+ *
+ * in	params[0].value.a:	lock state
+ */
+#define TA_AVB_CMD_WRITE_LOCK_STATE	3
+
+#endif /* __TA_AVB_H */