Commit dea73a34 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

Merge tag 'tee-bus-for-5.1' of... 

Merge tag 'tee-bus-for-5.1' of https://git.linaro.org/people/jens.wiklander/linux-tee into arm/drivers

Introduce TEE bus driver framework

- supp_nowait flag for non-blocking tee requests
- The tee bus driver framework
- OP-TEE TEE bus device enumeration support
- An OP-TEE based rng driver

* tag 'tee-bus-for-5.1' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  hwrng: add OP-TEE based rng driver
  tee: optee: add TEE bus device enumeration support
  tee: add bus driver framework for TEE based devices
  tee: add supp_nowait flag in tee_context struct
parents 03138ef9 5fe8b1cc

MAINTAINERS

+5 −0
Original line number Diff line number Diff line
@@ -11264,6 +11264,11 @@ M: Jens Wiklander <jens.wiklander@linaro.org> 
S:	Maintained

F:	drivers/tee/optee/



OP-TEE RANDOM NUMBER GENERATOR (RNG) DRIVER

M:	Sumit Garg <sumit.garg@linaro.org>

S:	Maintained

F:	drivers/char/hw_random/optee-rng.c



OPA-VNIC DRIVER

M:	Dennis Dalessandro <dennis.dalessandro@intel.com>

M:	Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>

drivers/char/hw_random/Kconfig

+15 −0
Original line number Diff line number Diff line
@@ -424,6 +424,21 @@ config HW_RANDOM_EXYNOS 
	  will be called exynos-trng.



	  If unsure, say Y.



config HW_RANDOM_OPTEE

	tristate "OP-TEE based Random Number Generator support"

	depends on OPTEE

	default HW_RANDOM

	help

	  This  driver provides support for OP-TEE based Random Number

	  Generator on ARM SoCs where hardware entropy sources are not

	  accessible to normal world (Linux).



	  To compile this driver as a module, choose M here: the module

	  will be called optee-rng.



	  If unsure, say Y.



endif # HW_RANDOM



config UML_RANDOM

drivers/char/hw_random/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -38,3 +38,4 @@ obj-$(CONFIG_HW_RANDOM_CAVIUM) += cavium-rng.o cavium-rng-vf.o 
obj-$(CONFIG_HW_RANDOM_MTK)	+= mtk-rng.o

obj-$(CONFIG_HW_RANDOM_S390) += s390-trng.o

obj-$(CONFIG_HW_RANDOM_KEYSTONE) += ks-sa-rng.o

obj-$(CONFIG_HW_RANDOM_OPTEE) += optee-rng.o

drivers/char/hw_random/optee-rng.c

0 → 100644
+298 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (C) 2018-2019 Linaro Ltd.

 */



#include <linux/delay.h>

#include <linux/of.h>

#include <linux/hw_random.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/tee_drv.h>

#include <linux/uuid.h>



#define DRIVER_NAME "optee-rng"



#define TEE_ERROR_HEALTH_TEST_FAIL	0x00000001



/*

 * TA_CMD_GET_ENTROPY - Get Entropy from RNG

 *

 * param[0] (inout memref) - Entropy buffer memory reference

 * param[1] unused

 * param[2] unused

 * param[3] unused

 *

 * Result:

 * TEE_SUCCESS - Invoke command success

 * TEE_ERROR_BAD_PARAMETERS - Incorrect input param

 * TEE_ERROR_NOT_SUPPORTED - Requested entropy size greater than size of pool

 * TEE_ERROR_HEALTH_TEST_FAIL - Continuous health testing failed

 */

#define TA_CMD_GET_ENTROPY		0x0



/*

 * TA_CMD_GET_RNG_INFO - Get RNG information

 *

 * param[0] (out value) - value.a: RNG data-rate in bytes per second

 *                        value.b: Quality/Entropy per 1024 bit of data

 * param[1] unused

 * param[2] unused

 * param[3] unused

 *

 * Result:

 * TEE_SUCCESS - Invoke command success

 * TEE_ERROR_BAD_PARAMETERS - Incorrect input param

 */

#define TA_CMD_GET_RNG_INFO		0x1



#define MAX_ENTROPY_REQ_SZ		(4 * 1024)



/**

 * struct optee_rng_private - OP-TEE Random Number Generator private data

 * @dev:		OP-TEE based RNG device.

 * @ctx:		OP-TEE context handler.

 * @session_id:		RNG TA session identifier.

 * @data_rate:		RNG data rate.

 * @entropy_shm_pool:	Memory pool shared with RNG device.

 * @optee_rng:		OP-TEE RNG driver structure.

 */

struct optee_rng_private {

	struct device *dev;

	struct tee_context *ctx;

	u32 session_id;

	u32 data_rate;

	struct tee_shm *entropy_shm_pool;

	struct hwrng optee_rng;

};



#define to_optee_rng_private(r) \

		container_of(r, struct optee_rng_private, optee_rng)



static size_t get_optee_rng_data(struct optee_rng_private *pvt_data,

				 void *buf, size_t req_size)

{

	u32 ret = 0;

	u8 *rng_data = NULL;

	size_t rng_size = 0;

	struct tee_ioctl_invoke_arg inv_arg = {0};

	struct tee_param param[4] = {0};



	/* Invoke TA_CMD_GET_ENTROPY function of Trusted App */

	inv_arg.func = TA_CMD_GET_ENTROPY;

	inv_arg.session = pvt_data->session_id;

	inv_arg.num_params = 4;



	/* Fill invoke cmd params */

	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;

	param[0].u.memref.shm = pvt_data->entropy_shm_pool;

	param[0].u.memref.size = req_size;

	param[0].u.memref.shm_offs = 0;



	ret = tee_client_invoke_func(pvt_data->ctx, &inv_arg, param);

	if ((ret < 0) || (inv_arg.ret != 0)) {

		dev_err(pvt_data->dev, "TA_CMD_GET_ENTROPY invoke err: %x\n",

			inv_arg.ret);

		return 0;

	}



	rng_data = tee_shm_get_va(pvt_data->entropy_shm_pool, 0);

	if (IS_ERR(rng_data)) {

		dev_err(pvt_data->dev, "tee_shm_get_va failed\n");

		return 0;

	}



	rng_size = param[0].u.memref.size;

	memcpy(buf, rng_data, rng_size);



	return rng_size;

}



static int optee_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)

{

	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);

	size_t read = 0, rng_size = 0;

	int timeout = 1;

	u8 *data = buf;



	if (max > MAX_ENTROPY_REQ_SZ)

		max = MAX_ENTROPY_REQ_SZ;



	while (read == 0) {

		rng_size = get_optee_rng_data(pvt_data, data, (max - read));



		data += rng_size;

		read += rng_size;



		if (wait) {

			if (timeout-- == 0)

				return read;

			msleep((1000 * (max - read)) / pvt_data->data_rate);

		} else {

			return read;

		}

	}



	return read;

}



static int optee_rng_init(struct hwrng *rng)

{

	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);

	struct tee_shm *entropy_shm_pool = NULL;



	entropy_shm_pool = tee_shm_alloc(pvt_data->ctx, MAX_ENTROPY_REQ_SZ,

					 TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);

	if (IS_ERR(entropy_shm_pool)) {

		dev_err(pvt_data->dev, "tee_shm_alloc failed\n");

		return PTR_ERR(entropy_shm_pool);

	}



	pvt_data->entropy_shm_pool = entropy_shm_pool;



	return 0;

}



static void optee_rng_cleanup(struct hwrng *rng)

{

	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);



	tee_shm_free(pvt_data->entropy_shm_pool);

}



static struct optee_rng_private pvt_data = {

	.optee_rng = {

		.name		= DRIVER_NAME,

		.init		= optee_rng_init,

		.cleanup	= optee_rng_cleanup,

		.read		= optee_rng_read,

	}

};



static int get_optee_rng_info(struct device *dev)

{

	u32 ret = 0;

	struct tee_ioctl_invoke_arg inv_arg = {0};

	struct tee_param param[4] = {0};



	/* Invoke TA_CMD_GET_RNG_INFO function of Trusted App */

	inv_arg.func = TA_CMD_GET_RNG_INFO;

	inv_arg.session = pvt_data.session_id;

	inv_arg.num_params = 4;



	/* Fill invoke cmd params */

	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;



	ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);

	if ((ret < 0) || (inv_arg.ret != 0)) {

		dev_err(dev, "TA_CMD_GET_RNG_INFO invoke err: %x\n",

			inv_arg.ret);

		return -EINVAL;

	}



	pvt_data.data_rate = param[0].u.value.a;

	pvt_data.optee_rng.quality = param[0].u.value.b;



	return 0;

}



static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)

{

	if (ver->impl_id == TEE_IMPL_ID_OPTEE)

		return 1;

	else

		return 0;

}



static int optee_rng_probe(struct device *dev)

{

	struct tee_client_device *rng_device = to_tee_client_device(dev);

	int ret = 0, err = -ENODEV;

	struct tee_ioctl_open_session_arg sess_arg = {0};



	/* Open context with TEE driver */

	pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,

					       NULL);

	if (IS_ERR(pvt_data.ctx))

		return -ENODEV;



	/* Open session with hwrng Trusted App */

	memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);

	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;

	sess_arg.num_params = 0;



	ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);

	if ((ret < 0) || (sess_arg.ret != 0)) {

		dev_err(dev, "tee_client_open_session failed, err: %x\n",

			sess_arg.ret);

		err = -EINVAL;

		goto out_ctx;

	}

	pvt_data.session_id = sess_arg.session;



	err = get_optee_rng_info(dev);

	if (err)

		goto out_sess;



	err = hwrng_register(&pvt_data.optee_rng);

	if (err) {

		dev_err(dev, "hwrng registration failed (%d)\n", err);

		goto out_sess;

	}



	pvt_data.dev = dev;



	return 0;



out_sess:

	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);

out_ctx:

	tee_client_close_context(pvt_data.ctx);



	return err;

}



static int optee_rng_remove(struct device *dev)

{

	hwrng_unregister(&pvt_data.optee_rng);

	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);

	tee_client_close_context(pvt_data.ctx);



	return 0;

}



const struct tee_client_device_id optee_rng_id_table[] = {

	{UUID_INIT(0xab7a617c, 0xb8e7, 0x4d8f,

		   0x83, 0x01, 0xd0, 0x9b, 0x61, 0x03, 0x6b, 0x64)},

	{}

};



MODULE_DEVICE_TABLE(tee, optee_rng_id_table);



static struct tee_client_driver optee_rng_driver = {

	.id_table	= optee_rng_id_table,

	.driver		= {

		.name		= DRIVER_NAME,

		.bus		= &tee_bus_type,

		.probe		= optee_rng_probe,

		.remove		= optee_rng_remove,

	},

};



static int __init optee_rng_mod_init(void)

{

	return driver_register(&optee_rng_driver.driver);

}



static void __exit optee_rng_mod_exit(void)

{

	driver_unregister(&optee_rng_driver.driver);

}



module_init(optee_rng_mod_init);

module_exit(optee_rng_mod_exit);



MODULE_LICENSE("GPL v2");

MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");

MODULE_DESCRIPTION("OP-TEE based random number generator driver");

drivers/tee/optee/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -5,3 +5,4 @@ optee-objs += call.o 
optee-objs += rpc.o

optee-objs += supp.o

optee-objs += shm_pool.o

optee-objs += device.o

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