[RFC PATCH 2/2] tee: add OP-TEE driver

[Jens Wiklander]

Adds mostly stubbed OP-TEE driver which also can be compiled as a
loadable module.

Signed-off-by: Jens Wiklander <jens.wiklander at linaro.org>
---
 drivers/tee/Kconfig        |  10 +++
 drivers/tee/Makefile       |   1 +
 drivers/tee/optee/Kconfig  |   7 ++
 drivers/tee/optee/Makefile |   2 +
 drivers/tee/optee/core.c   | 192 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 212 insertions(+)
 create mode 100644 drivers/tee/optee/Kconfig
 create mode 100644 drivers/tee/optee/Makefile
 create mode 100644 drivers/tee/optee/core.c

diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
index 64a8cd7..b269276 100644
--- a/drivers/tee/Kconfig
+++ b/drivers/tee/Kconfig
@@ -6,3 +6,13 @@ config TEE
 	help
 	  This implements a generic interface towards a Trusted Execution
 	  Environment (TEE).
+
+if TEE
+
+menu "TEE drivers"
+
+source "drivers/tee/optee/Kconfig"
+
+endmenu
+
+endif
diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
index 60d2dab..53f3c76 100644
--- a/drivers/tee/Makefile
+++ b/drivers/tee/Makefile
@@ -1,3 +1,4 @@
 obj-y += tee.o
 obj-y += tee_shm.o
 obj-y += tee_shm_pool.o
+obj-$(CONFIG_OPTEE) += optee/
diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
new file mode 100644
index 0000000..f43af5e
--- /dev/null
+++ b/drivers/tee/optee/Kconfig
@@ -0,0 +1,7 @@
+# OP-TEE Trusted Execution Environment Configuration
+config OPTEE
+	tristate "OP-TEE"
+	default n
+	select DMA_CMA
+	help
+	  This implements the OP-TEE Trusted Execution Environment (TEE) driver.
diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile
new file mode 100644
index 0000000..124d22c
--- /dev/null
+++ b/drivers/tee/optee/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_OPTEE) += optee.o
+optee-objs += core.o
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
new file mode 100644
index 0000000..e0f0755
--- /dev/null
+++ b/drivers/tee/optee/core.c
@@ -0,0 +1,192 @@
+/*
+ * Copyright (c) 2015, Linaro Limited
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-contiguous.h>
+#include <linux/cma.h>
+#include <linux/tee/tee_drv.h>
+
+#define DRIVER_NAME "tee-optee"
+#define OPTEE_VERSION	1
+
+struct optee {
+	struct tee_device *supp_teedev;
+	struct tee_device *teedev;
+	struct device *dev;
+	struct tee_shm_pool *pool;
+};
+
+struct optee_context_data {
+	int dummy;
+};
+
+static void optee_get_version(struct tee_context *ctx,
+		u32 *version, u8 *uuid)
+{
+	*version = OPTEE_VERSION;
+	memset(uuid, 0, TEE_UUID_SIZE);
+}
+
+static int optee_open(struct tee_context *ctx)
+{
+	ctx->data = kzalloc(sizeof(struct optee_context_data), GFP_KERNEL);
+	if (!ctx->data)
+		return -ENOMEM;
+	return 0;
+}
+
+static void optee_release(struct tee_context *ctx)
+{
+	kfree(ctx->data);
+	ctx->data = NULL;
+}
+
+static int optee_cmd(struct tee_context *ctx, void __user *buf, size_t len)
+{
+	return -EINVAL;
+}
+
+static int optee_shm_share(struct tee_shm *shm)
+{
+	/* No special action needed to share memory with OP-TEE */
+	return 0;
+}
+
+static void optee_shm_unshare(struct tee_shm *shm)
+{
+}
+
+static struct tee_driver_ops optee_ops = {
+	.get_version = optee_get_version,
+	.open = optee_open,
+	.release = optee_release,
+	.cmd = optee_cmd,
+	.shm_share = optee_shm_share,
+	.shm_unshare = optee_shm_unshare,
+};
+
+static struct tee_desc optee_desc = {
+	.name = DRIVER_NAME "-clnt",
+	.ops = &optee_ops,
+	.owner = THIS_MODULE,
+};
+
+static int optee_supp_cmd(struct tee_context *teectx, void __user *buf,
+			size_t len)
+{
+	return -EINVAL;
+}
+
+static struct tee_driver_ops optee_supp_ops = {
+	.get_version = optee_get_version,
+	.open = optee_open,
+	.release = optee_release,
+	.cmd = optee_supp_cmd,
+	.shm_share = optee_shm_share,
+	.shm_unshare = optee_shm_unshare,
+};
+
+static struct tee_desc optee_supp_desc = {
+	.name = DRIVER_NAME "-supp",
+	.ops = &optee_supp_ops,
+	.owner = THIS_MODULE,
+	.flags = TEE_DESC_PRIVILEGED,
+};
+
+static int optee_probe(struct platform_device *pdev)
+{
+	struct tee_shm_pool *pool;
+	struct optee *optee;
+	u_long vaddr;
+	phys_addr_t paddr;
+	size_t size;
+	int ret;
+
+	pool = tee_shm_pool_alloc_cma(&pdev->dev, &vaddr, &paddr, &size);
+	if (IS_ERR(pool))
+		return PTR_ERR(pool);
+
+	dev_info(&pdev->dev, "pool: va 0x%lx pa 0x%lx size %zx\n",
+		vaddr, (u_long)paddr, size);
+
+	optee = devm_kzalloc(&pdev->dev, sizeof(*optee), GFP_KERNEL);
+	if (!optee) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	optee->dev = &pdev->dev;
+
+	optee->teedev = tee_register(&optee_desc, &pdev->dev, pool, optee);
+	if (IS_ERR(optee->teedev)) {
+		ret = PTR_ERR(optee->teedev);
+		goto err;
+	}
+
+	optee->supp_teedev = tee_register(&optee_supp_desc, &pdev->dev, pool,
+					  optee);
+	if (!optee->teedev) {
+		ret = PTR_ERR(optee->teedev);
+		goto err;
+	}
+
+	optee->pool = pool;
+	platform_set_drvdata(pdev, optee);
+
+	dev_info(&pdev->dev, "initialized driver\n");
+	return 0;
+err:
+	if (optee && optee->teedev)
+		tee_unregister(optee->teedev);
+	if (pool)
+		tee_shm_pool_free(pool);
+	return ret;
+}
+
+static int optee_remove(struct platform_device *pdev)
+{
+	struct optee *optee = platform_get_drvdata(pdev);
+
+	tee_unregister(optee->teedev);
+	tee_unregister(optee->supp_teedev);
+	tee_shm_pool_free(optee->pool);
+
+	return 0;
+}
+
+static const struct of_device_id optee_match[] = {
+	{ .compatible = "optee,optee-tz" },
+	{},
+};
+
+static struct platform_driver optee_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = optee_match,
+	},
+	.probe = optee_probe,
+	.remove = optee_remove,
+};
+
+module_platform_driver(optee_driver);
+
+MODULE_AUTHOR("Linaro");
+MODULE_DESCRIPTION("OP-TEE TEE driver");
+MODULE_SUPPORTED_DEVICE("");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1